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Sample records for beam radiation-induced xerostomia

  1. Radiation-induced xerostomia in a patient with nasopharyngeal ...

    African Journals Online (AJOL)

    OBJECTIVE: This study reports a case of radiation-induced xerstomia in a patient with nasopharyngeal cancer, to emphasize the need for prompt oral care to prevent untoward effects of xerostomia and to improve patients' quality of life. CASE REPORT: A 60 year old man diagnosed of radiation-induced xerostomia, after 6 ...

  2. Hyperbaric oxygen therapy for the treatment of radiation-induced xerostomia: a systematic review.

    Science.gov (United States)

    Fox, Nyssa F; Xiao, Christopher; Sood, Amit J; Lovelace, Tiffany L; Nguyen, Shaun A; Sharma, Anand; Day, Terry A

    2015-07-01

    Radiation-induced xerostomia is one of the most common morbidities of radiation therapy in patients with head and neck cancer. However, in spite of its high rate of occurrence, there are few effective therapies available for its management. The aim of this study was to assess the efficacy of hyperbaric oxygen on the treatment of radiation-induced xerostomia and xerostomia-related quality of life. PubMed, Google Scholar, and the Cochrane Library were searched for retrospective or prospective trials assessing subjective xerostomia, objective xerostomia, or xerostomia-related quality of life. To be included, patients had to have received radiation therapy for head and neck cancer, but not hyperbaric oxygen therapy (HBOT). The systematic review initially identified 293 potential articles. Seven studies, comprising 246 patients, qualified for inclusion. Of the included studies, 6 of 7 were prospective in nature, and 1 was a retrospective study; and 2 of the 7 were controlled studies. HBOT may have utility for treating radiation-induced xerostomia refractory to other therapies. Additionally, HBOT may induce long-term improvement in subjective assessments of xerostomia, whereas other therapies currently available only provide short-term relief. The strength of these conclusions is limited by the lack of randomized controlled clinical trials. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Submandibular salivary gland transfer prevents radiation-induced xerostomia

    International Nuclear Information System (INIS)

    Jha, Naresh; Seikaly, Hadi; McGaw, Timothy; Coulter, Linda

    2000-01-01

    Background: Xerostomia is a significant morbidity of radiation therapy in the management of head and neck cancers. We hypothesized that the surgical transfer of one submandibular salivary gland to submental space, outside the proposed radiation field, prior to starting radiation treatment, would prevent xerostomia. Methods: We are conducting a prospective clinical trial where the submandibular gland is transferred as part of the surgical intervention. The patients are followed clinically, with salivary flow studies and University of Washington quality of life questionnaire. Results: We report early results of 16 patients who have undergone this procedure. Seven patients have finished and 2 patients are currently undergoing radiation treatment. In 2 patients, no postoperative radiation treatment was indicated. Two patients are waiting to start radiation treatment and 2 patients refused treatment after surgery. The surgical transfer was abandoned in 1 patient. All of the transferred salivary glands were positioned outside the proposed radiation fields and were functional. The patients did not complain of any xerostomia and developed only minimal oral mucositis. There were no surgical complications. Conclusions: Surgical transfer of a submandibular salivary gland to the submental space (outside the radiation field) preserves its function and prevents the development of radiation-induced xerostomia

  4. Salivary gland transfer to prevent radiation-induced xerostomia: a systematic review and meta-analysis.

    Science.gov (United States)

    Sood, Amit J; Fox, Nyssa F; O'Connell, Brendan P; Lovelace, Tiffany L; Nguyen, Shaun A; Sharma, Anand K; Hornig, Joshua D; Day, Terry A

    2014-02-01

    Salivary gland transfer (SGT) has the potential to prevent radiation-induced xerostomia. We attempt to analyze the efficacy of SGT in prevention of xerostomia and maintenance of salivary flow rates after radiation treatment (XRT). Systematic review and meta-analysis. Primary endpoint was efficacy of SGT in prevention of radiation-induced xerostomia. Secondary endpoint was change from baseline of unstimulated and stimulated salivary flow rates after XRT. Seven articles, accruing data from 12 institutions, met inclusion criteria. In a total of 177 patients at mean follow-up of 22.7months, SGT prevented radiation-induced xerostomia in 82.7% (95% CI, 76.6-87.7%) of patients. Twelve months after XRT, unstimulated and stimulated salivary flow rates rose to 88% and 76% of baseline values, respectively. In comparison to control subjects twelve months after XRT, SGT subjects' unstimulated (75% vs. 11%) and stimulated (86% vs. 8%) salivary flow rates were drastically higher in SGT patients. Salivary gland transfer appears to be highly effective in preventing the incidence of xerostomia in patients receiving definitive head and neck radiation therapy. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Recovery time from radiation-induced xerostomia and impairment of salivary secretion

    International Nuclear Information System (INIS)

    Fukutomi, Yukimi; Kawakami, Toshiaki; Murase, Kenya; Fujii, Takashi; Ikezoe, Junpei

    2000-01-01

    Between June 1995 and August 1997, we treated 23 patients with head and neck malignancies using an x-ray beam and then interviewed the patients to determine the degree of subjective salivary secretion and xerostomia after long-term radiation therapy. Interviews were continued for a maximum 179 weeks (mean, 76.3 weeks) after irradiation. We scored the results as the degree of subjective salivary secretion, then noted the recovery time for salivary secretion and xerostomia. When salivary glands had been irradiated to a total dose of 30 to 60 Gy, salivary secretion and oral dryness recovered within three years in 72% (13/18) and 67% (13/18) of the patients, respectively. However, these symptoms never recovered to their original levels when the total dose was more than 60 Gy. The acute and late effects of radiation therapy may induce a risk of dental caries, oral dryness, and osteoradionecrosis as well as taste impairment. Therefore, education as to dental and oral care is mandatory for patients who will be or who have been treated with radiotherapy. (author)

  6. Is Pilocarpine Effective in Preventing Radiation-Induced Xerostomia? A Systematic Review and Meta-analysis.

    Science.gov (United States)

    Yang, Wei-fa; Liao, Gui-qing; Hakim, Samer G; Ouyang, Dai-qiao; Ringash, Jolie; Su, Yu-xiong

    2016-03-01

    To evaluate the efficacy of concomitant administration of pilocarpine on radiation-induced xerostomia in patients with head and neck cancers. The PubMed, Web of Science, Cochrane Library, and ClinicalTrials were searched to identify randomized, controlled trials studying the effect of concomitant administration of pilocarpine for radiation-induced xerostomia. Included trials were systematically reviewed, and quantifiable outcomes were pooled for meta-analysis. Outcomes of interest included salivary flow, clinician-rated xerostomia grade, patient-reported xerostomia scoring, quality of life, and adverse effects. Six prospective, randomized, controlled trials in 8 articles were included in this systematic review. The total number of patients was 369 in the pilocarpine group and 367 in the control group. Concomitant administration of pilocarpine during radiation could increase the unstimulated salivary flow rate in a period of 3 to 6 months after treatment, and also reduce the clinician-rated xerostomia grade. Patient-reported xerostomia was not significantly impacted by pilocarpine in the initial 3 months but was superior at 6 months. No significant difference of stimulated salivary flow rate could be confirmed between the 2 arms. Adverse effects of pilocarpine were mild and tolerable. The concomitant administration of pilocarpine during radiation increases unstimulated salivary flow rate and reduces clinician-rated xerostomia grade after radiation. It also relieves patients' xerostomia at 6 months and possibly at 12 months. However, pilocarpine has no effect on stimulated salivary flow rate. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Is Pilocarpine Effective in Preventing Radiation-Induced Xerostomia? A Systematic Review and Meta-analysis

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Wei-fa; Liao, Gui-qing [Department of Oral and Maxillofacial Surgery, Guanghua School of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou (China); Hakim, Samer G. [Department of Oral and Maxillofacial Surgery, University of Lübeck, Lübeck (Germany); Ouyang, Dai-qiao [Department of Oral and Maxillofacial Surgery, Guanghua School of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou (China); Ringash, Jolie [Department of Radiation Oncology, Princess Margaret Cancer Centre and the University of Toronto, Toronto, Ontario (Canada); Su, Yu-xiong, E-mail: richsu@hku.hk [Division of Oral and Maxillofacial Surgery, Faculty of Dentistry, University of Hong Kong, Hong Kong (China)

    2016-03-01

    Purpose: To evaluate the efficacy of concomitant administration of pilocarpine on radiation-induced xerostomia in patients with head and neck cancers. Methods and Materials: The PubMed, Web of Science, Cochrane Library, and ClinicalTrials were searched to identify randomized, controlled trials studying the effect of concomitant administration of pilocarpine for radiation-induced xerostomia. Included trials were systematically reviewed, and quantifiable outcomes were pooled for meta-analysis. Outcomes of interest included salivary flow, clinician-rated xerostomia grade, patient-reported xerostomia scoring, quality of life, and adverse effects. Results: Six prospective, randomized, controlled trials in 8 articles were included in this systematic review. The total number of patients was 369 in the pilocarpine group and 367 in the control group. Concomitant administration of pilocarpine during radiation could increase the unstimulated salivary flow rate in a period of 3 to 6 months after treatment, and also reduce the clinician-rated xerostomia grade. Patient-reported xerostomia was not significantly impacted by pilocarpine in the initial 3 months but was superior at 6 months. No significant difference of stimulated salivary flow rate could be confirmed between the 2 arms. Adverse effects of pilocarpine were mild and tolerable. Conclusions: The concomitant administration of pilocarpine during radiation increases unstimulated salivary flow rate and reduces clinician-rated xerostomia grade after radiation. It also relieves patients' xerostomia at 6 months and possibly at 12 months. However, pilocarpine has no effect on stimulated salivary flow rate.

  8. Is Pilocarpine Effective in Preventing Radiation-Induced Xerostomia? A Systematic Review and Meta-analysis

    International Nuclear Information System (INIS)

    Yang, Wei-fa; Liao, Gui-qing; Hakim, Samer G.; Ouyang, Dai-qiao; Ringash, Jolie; Su, Yu-xiong

    2016-01-01

    Purpose: To evaluate the efficacy of concomitant administration of pilocarpine on radiation-induced xerostomia in patients with head and neck cancers. Methods and Materials: The PubMed, Web of Science, Cochrane Library, and ClinicalTrials were searched to identify randomized, controlled trials studying the effect of concomitant administration of pilocarpine for radiation-induced xerostomia. Included trials were systematically reviewed, and quantifiable outcomes were pooled for meta-analysis. Outcomes of interest included salivary flow, clinician-rated xerostomia grade, patient-reported xerostomia scoring, quality of life, and adverse effects. Results: Six prospective, randomized, controlled trials in 8 articles were included in this systematic review. The total number of patients was 369 in the pilocarpine group and 367 in the control group. Concomitant administration of pilocarpine during radiation could increase the unstimulated salivary flow rate in a period of 3 to 6 months after treatment, and also reduce the clinician-rated xerostomia grade. Patient-reported xerostomia was not significantly impacted by pilocarpine in the initial 3 months but was superior at 6 months. No significant difference of stimulated salivary flow rate could be confirmed between the 2 arms. Adverse effects of pilocarpine were mild and tolerable. Conclusions: The concomitant administration of pilocarpine during radiation increases unstimulated salivary flow rate and reduces clinician-rated xerostomia grade after radiation. It also relieves patients' xerostomia at 6 months and possibly at 12 months. However, pilocarpine has no effect on stimulated salivary flow rate.

  9. XRCC3 polymorphisms are associated with the risk of developing radiation-induced late xerostomia in nasopharyngeal carcinoma patients treated with intensity modulation radiated therapy.

    Science.gov (United States)

    Zou, Yan; Song, Tao; Yu, Wei; Zhao, Ruping; Wang, Yong; Xie, Ruifei; Chen, Tian; Wu, Bo; Wu, Shixiu

    2014-03-01

    The incidence of radiation-induced late xerostomia varies greatly in nasopharyngeal carcinoma patients treated with radiotherapy. The single-nucleotide polymorphisms in genes involved in DNA repair and fibroblast proliferation may be correlated with such variability. The purpose of this paper was to evaluate the association between the risk of developing radiation-induced late xerostomia and four genetic polymorphisms: TGFβ1 C-509T, TGFβ1 T869C, XRCC3 722C>T and ATM 5557G>A in nasopharyngeal carcinoma patients treated with Intensity Modulation Radiated Therapy. The severity of late xerostomia was assessed using a patient self-reported validated xerostomia questionnaire. Polymerase chain reaction-ligation detection reaction methods were performed to determine individual genetic polymorphism. The development of radiation-induced xerostomia associated with genetic polymorphisms was modeled using Cox proportional hazards, accounting for equivalent uniform dose. A total of 43 (41.7%) patients experienced radiation-induced late xerostomia. Univariate Cox proportional hazard analyses showed a higher risk of late xerostomia for patients with XRCC3 722 TT/CT alleles. In multivariate analysis adjusted for clinical and dosimetric factors, XRCC3 722C>T polymorphisms remained a significant factor for higher risk of late xerostomia. To our knowledge, this is the first study that demonstrated an association between genetic polymorphisms and the risk of radiation-induced late xerostomia in nasopharyngeal carcinoma patients treated with Intensity Modulation Radiated Therapy. Our findings suggest that the polymorphisms in XRCC3 are significantly associated with the risk of developing radiation-induced late xerostomia.

  10. The standardization of acupuncture treatment for radiation-induced xerostomia: A literature review.

    Science.gov (United States)

    Li, Ling-Xin; Tian, Guang; He, Jing

    2016-07-01

    To assess the relative standardization of acupuncture protocols for radiation-induced xerostomia. A literature search was carried out up to November 10, 2012 in the databases PubMed/MEDLINE, EMBASE and China National Knowledge Infrastruction with the terms: radiation-induced xerostomia, acupuncture, acupuncture treatment, and acupuncture therapy. Five ancient Chinese classic acupuncture works were also reviewed with the keywords "dry mouth, thirst, dry tongue, dry eyes and dry lips" to search the effective acupuncture points for dry mouth-associated symptoms in ancient China. Twenty-two full-text articles relevant to acupuncture treatment for radiation-induced xerostomia were included and a total of 48 acupuncture points were searched in the 5 ancient Chinese classic acupuncture works, in which the most commonly used points were Chengjiang (CV24), Shuigou (GV 26), Duiduan (GV 27), Jinjin (EX-HN 12), and Yuye (EX-HN 13) on head and neck, Sanjian (LI 3), Shangyang (LI 1), Shaoshang (LU 11), Shaoze (SI 1), Xialian (LI 8) on hand, Fuliu (KI 7), Dazhong (KI 4), Zuqiaoyin (GB 44), Taichong (LR 3), Zhaohai (KI 6) on foot, Burong (ST 19), Zhangmen (LR 13), Tiantu (CV 22), Qimen (LR 14) on abdomen, Feishu (BL 13), Danshu (BL 19), Xiaochaogshu (BL 27), Ganshu (BL 18) on back, Shenmen (TF 4), Shen (CO10, Kidney), Yidan (CO11, Pancreas) and Pi (CO13, Spleen) on ear. There were considerable heterogeneities in the current acupuncture treatment protocols for radiation-induced xerostomia. Based on the results of the review and the personal perspectives, the authors provide a recommendation for manual acupuncture protocols in treating radiationinduced xerostomia patients with head and neck cancer.

  11. Pilocarpine and carbacholine in treatment of radiation-induced xerostomia

    International Nuclear Information System (INIS)

    Joensuu, H.; Bostroem, P.; Makkonen, T.

    1993-01-01

    Twenty-four patients with radiation-related xerostomia were treated with oral pilocarpine solution 6 mg t.i.d., and after a 4-week drug-free period 16 of these patients were treated with carbacholine 2 mg tablets t.i.d. Basal and stimulated whole saliva flow rates were measured before commencing the drug treatment, and after 1 and 12 weeks on treatment. On a subjective linear scale both pilocarpine (p=0.01) and carbacholine (p=0.02) improved mouth moistness. Only 2 of the 8 patients with no basal or stimulated saliva flow reported some subjective benefit from the drug treatment, whereas all 8 patients with less severe xerostomia improved (p=0.007). However, the salivary flow rates measured 12 h after the last drug dose did not improve with either drug. Both drugs were generally well tolerated. It is concluded that both drugs may be useful in the treatment of radiation-induced xerostomia among patients with residual salivary function. (author). 6 refs., tabs

  12. Acupuncture treatment of patients with radiation-induced xerostomia

    International Nuclear Information System (INIS)

    Blom, M.; Dawidson, I.; Johnson, G.; Angmar-Maansson, B.; Fernberg, J.-O.

    1996-01-01

    Xerostomia is a common and usually irreversible side effect in patients receiving radiation therapy (>50 Gy) for head and neck cancer. Of 38 patients with radiation-induced xerostomia, 20 in the experimental group were treated with classical acupuncture and 18 patients in the control group received superficial acupuncture as placebo. Within both groups the patients showed significantly increased salivary flow rates after the acupuncture treatment. In the experimental group 68% and in the control group 50% of the patients had increased salivary flow rates at the end of the observation period. Among those patients who had had all their salivary glands irradiated, 50% in both groups showed increased salivary flow rates (>20%) by the end of the observation period of 1 year. The study indicates that among the patients who had increased salivary flow rates already after the first 12 acupuncture sessions, the majority had high probability of continual improvement after the completion of acupuncture treatment. (Author)

  13. Acupuncture treatment of patients with radiation-induced xerostomia

    Energy Technology Data Exchange (ETDEWEB)

    Blom, M.; Dawidson, I.; Johnson, G.; Angmar-Maansson, B. [Karolinska Inst., Huddinge (Sweden). Dept. of Cardiology; Fernberg, J.-O. [Karolinska Hospital, Stockholm (Sweden). Dept. of General Oncology

    1996-05-01

    Xerostomia is a common and usually irreversible side effect in patients receiving radiation therapy (>50 Gy) for head and neck cancer. Of 38 patients with radiation-induced xerostomia, 20 in the experimental group were treated with classical acupuncture and 18 patients in the control group received superficial acupuncture as placebo. Within both groups the patients showed significantly increased salivary flow rates after the acupuncture treatment. In the experimental group 68% and in the control group 50% of the patients had increased salivary flow rates at the end of the observation period. Among those patients who had had all their salivary glands irradiated, 50% in both groups showed increased salivary flow rates (>20%) by the end of the observation period of 1 year. The study indicates that among the patients who had increased salivary flow rates already after the first 12 acupuncture sessions, the majority had high probability of continual improvement after the completion of acupuncture treatment. (Author).

  14. A survey of techniques to reduce and manage external beam radiation-induced xerostomia in British oncology and radiotherapy departments

    International Nuclear Information System (INIS)

    Macknelly, Andrew; Day, Jane

    2009-01-01

    Xerostomia is the most common side effect of external beam radiotherapy to the head and neck [Anand A, Jain J, Negi P, Chaudhoory A, Sinha S, Choudhury P, et-al. Can dose reduction to one parotid gland prevent xerostomia? - A feasibility study for locally advanced head and neck cancer patients treated with intensity-modulated radiotherapy. Clinical Oncology 2006;18(6):497-504.]. A survey was carried out in British oncology departments to determine what treatment regimes, to minimise xerostomia, are used for patients with head-and-neck cancers treated with external beam radiotherapy. A semi-structured questionnaire consisting of both quantitative and qualitative questions was designed that asked departments which of the identified methods they used, why a method might not be currently employed, and whether its use had ever been considered. The study found that there are wide disparities between the techniques employed by oncology departments to avoid and reduce xerostomia in patients with cancers of the head and neck. The National Institute of Clinical Health and Excellence, [National Institute for Clinical Health and Excellence (NICE). Improving outcomes in head and neck cancers: the manual. London: Office of Public Sector Information; 2004.] for example, recommends that patients are given dental care and dietary advice but some departments did not appear to be doing this. Less than half of departments stated that they offer complementary therapies and less than 40% prescribed pilocarpine, a saliva-stimulant. Only two respondents stated that they use amifostine, a radioprotector, during radiotherapy treatment to the head and neck. The results also suggested a move toward using Intensity Modulated Radiotherapy (IMRT) for treating head-and-neck cancers which offers better normal tissue sparing than three-dimensional conformal radiotherapy. [Anand A, Jain J, Negi P, Chaudhoory A, Sinha S, Choudhury P, et al. Can dose reduction to one parotid gland prevent xerostomia

  15. Prevention of radiation induced xerostomia and improved quality of life: Submandibular salivary gland transfer

    International Nuclear Information System (INIS)

    Heck, K.

    2003-01-01

    Over 60,000 new cases of head and neck cancers, and approximately 15,000 deaths occur every year in the United States (1). Head and neck cancers affect more men then women by a factor of 2:1, although the incidence of women is increasing as a result of increased tobacco use (2). Over 90% of all head and neck cancers are squamous cell carcinomas; most of the remaining cancers are adenocarcinomas. A combination of radiation therapy and surgery is used as the standard, primary treatment modality. Xerostomia occurs when the salivary glands are affected by irradiation. Patients experiencing xerostomia are at an increased risk for a wide variety of oral problems; all adversely affecting one's quality of life. Currently patients make lifestyle changes, dietary modifications, and use artificial salivas, sprays, gels, and lozenges to help mask their xerostomia. However, none of these products stimulate natural salivary production and act as a replacement therapy rather then a cure for xerostomia. A new protocol, RTOG 1083 has been approved by the Radiation Therapy Oncology Group, which involves a surgical transfer of a submandibular salivary gland to the submental space (where it can be easily shielded) as a method of prevention of radiation induced xerostomia. (author)

  16. Effect of cepharanthin to prevent radiation induced xerostomia in head and neck cancer

    International Nuclear Information System (INIS)

    Imada, Hajime; Nomoto, Satoshi; Ohguri, Takayuki; Yahara, Katsuya; Kato, Fumio; Morioka, Tomoaki; Korogi Yukunori

    2004-01-01

    We retrospectively examined the effect of Cepharanthin to prevent radiation xerostomia in 37 cases of head and neck cancer. In the Cepharanthin group, the degree of xerostomia was milder than in the non-Cepharanthin group in spite of higher normal tissue complication probability (NTCP) and mean dose (MD) of parotid glands. In the non-Cepharanthin group, the degree of xerostomia was significantly correlated with NTCP and MD of parotid glands. MD of parotid glands and use of Cepharanthin were significantly related to more severe xerostomia by multivariate analysis with logistic regression. Cepharanthin may prevent radiation xerostomia after radiotherapy for head and neck cancer. (author)

  17. Prevention of radiation induced xerostomia by surgical transfer of submandibular salivary gland into the submental space

    International Nuclear Information System (INIS)

    Jha, Naresh; Seikaly, Hadi; Harris, Jeff; Williams, David; Liu, Richard; McGaw, Timothy; Hofmann, Henry; Robinson, Don; Hanson, John; Barnaby, Pam

    2003-01-01

    Background and purpose: Xerostomia is a significant morbidity of radiation treatment in the management of head and neck cancers. We hypothesized that the surgical transfer of one submandibular salivary gland to the submental space, where it can be shielded from radiation treatment (XRT), would prevent xerostomia. Materials and methods: We conducted a prospective Phase II clinical trial and the patients were followed clinically with salivary flow studies and the University of Washington Quality of Life questionnaire. Results: We report the results on 76 evaluable patients. The salivary gland transfer was done in 60 patients. Nine patients (of 60) did not have postoperative XRT and in eight patients (of 60) the transferred gland was not shielded from XRT due to proximity of disease. The median follow up is 14 months. Of the 43 patients with the salivary gland transfer and post-operative XRT with protection of the transferred gland, 81% have none or minimal xerostomia, and 19% developed moderate to severe xerostomia. Three patients (6.9%) developed local recurrence, five patients (11.6%) developed distant metastases and five patients (11.6%) have died. There were no complications attributed to the surgical procedure. Conclusion: Surgical transfer of a submandibular salivary gland to the submental space preserves its function and prevents the development of radiation induced xerostomia

  18. The role of stem cells in the prevention and treatment of radiation-induced xerostomia in patients with head and neck cancer.

    Science.gov (United States)

    Nevens, Daan; Nuyts, Sandra

    2016-06-01

    Xerostomia is an important complication following radiotherapy (RT) for head and neck cancer. Current treatment approaches are insufficient and can only temporarily relieve symptoms. New insights into the physiopathology of radiation-induced xerostomia might help us in this regard. This review discusses the current knowledge of salivary gland stem cells in radiation-induced xerostomia and their value in the prevention and treatment of this complication. Salivary gland stem cell transplantation, bone marrow-derived cell mobilization, molecular regulation of parotid stem cells, stem cell sparing RT, and adaptive RT are promising techniques that are discussed in this study. © 2016 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

  19. Impact of Radiation-Induced Xerostomia on Quality of Life After Primary Radiotherapy Among Patients With Head and Neck Cancer

    International Nuclear Information System (INIS)

    Jellema, Anke Petra; Slotman, Ben J.; Doornaert, Patricia; Leemans, C. Rene M.D.; Langendijk, Johannes A.

    2007-01-01

    Purpose: To investigate the impact of xerostomia on overall quality of life (QoL) outcome and related dimensions among head and neck cancer patients treated with primary radiotherapy. Methods and Materials: A total of 288 patients with Stage I-IV disease without distant metastases were included. Late xerostomia according to the Radiation Therapy Oncology Group (RTOG-xerostomia) and QoL (European Organization for Research and Treatment of Cancer QLC-C30) were assessed at baseline and every 6th month from 6 months to 24 months after radiotherapy. Results: A significant association was found between RTOG-xerostomia and overall QoL outcome (effect size [ES] 0.07, p 65 years). An analysis of the impact of RTOG-xerostomia on overall QoL outcome over time showed an increase from 0.09 at 6 months to 0.22 at 24 months. With elapsing time, a worsening was found for these individual scales with increasing RTOG-xerostomia. Conclusions: The results of this prospective study are the first to show a significant impact of radiation-induced xerostomia on QoL. Although the incidence of Grade ≥2 RTOG-xerostomia decreases with time, its impact on QoL increases. This finding emphasizes the importance of prevention of xerostomia

  20. A Phase II Study of Submandibular Gland Transfer Prior to Radiation for Prevention of Radiation-induced Xerostomia in Head-and-Neck Cancer (RTOG 0244)

    International Nuclear Information System (INIS)

    Jha, Naresh; Harris, Jonathan; Seikaly, Hadi; Jacobs, John R.; McEwan, A.J.B.; Robbins, K. Thomas; Grecula, John; Sharma, Anand K.; Ang, K. Kian

    2012-01-01

    Purpose: We report the results of a phase II study to determine the reproducibility of a submandibular salivary gland transfer (SGT) surgical technique for prevention of radiation (XRT)-induced xerostomia in a multi-institutional setting and to assess severity of xerostomia. Methods and Materials: Eligible patients had surgery for primary, neck dissection, and SGT, followed by XRT, during which the transferred salivary gland was shielded. Intensity modulated radiation therapy, amifostine, and pilocarpine were not allowed, but postoperative chemotherapy was allowed. Each operation was reviewed by 2 reviewers and radiation by 1 reviewer. If 13 or more (of 43) were “not per protocol,” then the technique would be considered not reproducible as per study design. The secondary endpoint was the rate of acute xerostomia, grade 2 or higher, and a rate of ≤51% was acceptable. Results: Forty-four of the total 49 patients were analyzable: male (81.8%), oropharynx (63.6%), stage IV (61.4%), median age 56.5 years. SGT was “per protocol” or within acceptable variation in 34 patients (77.3%) and XRT in 79.5%. Nine patients (20.9%) developed grade 2 acute xerostomia; 2 had grade 0-1 xerostomia (4.7%) but started on amifostine/pilocarpine. Treatment for these 11 patients (25.6%) was considered a failure for the xerostomia endpoint. Thirteen patients died; median follow-up for 31 surviving patients was 2.9 years. Two-year overall and disease-free survival rates were 76.4% and 71.7%, respectively. Conclusions: The technique of submandibular SGT is reproducible in a multicenter setting. Seventy-four percent of patients were prevented from XRT-induced acute xerostomia.

  1. A Phase II Study of Submandibular Gland Transfer Prior to Radiation for Prevention of Radiation-induced Xerostomia in Head-and-Neck Cancer (RTOG 0244)

    Energy Technology Data Exchange (ETDEWEB)

    Jha, Naresh, E-mail: naresh.jha@albertahealthservices.ca [University of Alberta, Cross Cancer Institute, Edmonton, Alberta (Canada); Harris, Jonathan [Radiation Therapy Oncology Group Statistical Center, Philadelphia, Pennsylvania (United States); Seikaly, Hadi [University of Alberta, Edmonton, Alberta (Canada); Jacobs, John R. [Wayne State University School of Medicine, Detroit, Michigan (United States); McEwan, A.J.B. [University of Alberta, Cross Cancer Institute, Edmonton, Alberta (Canada); Robbins, K. Thomas [St. John' s Hospital Cancer Institute, Springfield, Illinois (United States); Grecula, John [Ohio State University Medical Center, Columbus, Ohio (United States); Sharma, Anand K. [Medical University of South Carolina, Charleston, South Carolina (United States); Ang, K. Kian [University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2012-10-01

    Purpose: We report the results of a phase II study to determine the reproducibility of a submandibular salivary gland transfer (SGT) surgical technique for prevention of radiation (XRT)-induced xerostomia in a multi-institutional setting and to assess severity of xerostomia. Methods and Materials: Eligible patients had surgery for primary, neck dissection, and SGT, followed by XRT, during which the transferred salivary gland was shielded. Intensity modulated radiation therapy, amifostine, and pilocarpine were not allowed, but postoperative chemotherapy was allowed. Each operation was reviewed by 2 reviewers and radiation by 1 reviewer. If 13 or more (of 43) were 'not per protocol,' then the technique would be considered not reproducible as per study design. The secondary endpoint was the rate of acute xerostomia, grade 2 or higher, and a rate of {<=}51% was acceptable. Results: Forty-four of the total 49 patients were analyzable: male (81.8%), oropharynx (63.6%), stage IV (61.4%), median age 56.5 years. SGT was 'per protocol' or within acceptable variation in 34 patients (77.3%) and XRT in 79.5%. Nine patients (20.9%) developed grade 2 acute xerostomia; 2 had grade 0-1 xerostomia (4.7%) but started on amifostine/pilocarpine. Treatment for these 11 patients (25.6%) was considered a failure for the xerostomia endpoint. Thirteen patients died; median follow-up for 31 surviving patients was 2.9 years. Two-year overall and disease-free survival rates were 76.4% and 71.7%, respectively. Conclusions: The technique of submandibular SGT is reproducible in a multicenter setting. Seventy-four percent of patients were prevented from XRT-induced acute xerostomia.

  2. Apparent diffusion coefficient histogram analysis can evaluate radiation-induced parotid damage and predict late xerostomia degree in nasopharyngeal carcinoma.

    Science.gov (United States)

    Zhou, Nan; Guo, Tingting; Zheng, Huanhuan; Pan, Xia; Chu, Chen; Dou, Xin; Li, Ming; Liu, Song; Zhu, Lijing; Liu, Baorui; Chen, Weibo; He, Jian; Yan, Jing; Zhou, Zhengyang; Yang, Xiaofeng

    2017-09-19

    We investigated apparent diffusion coefficient (ADC) histogram analysis to evaluate radiation-induced parotid damage and predict xerostomia degrees in nasopharyngeal carcinoma (NPC) patients receiving radiotherapy. The imaging of bilateral parotid glands in NPC patients was conducted 2 weeks before radiotherapy (time point 1), one month after radiotherapy (time point 2), and four months after radiotherapy (time point 3). From time point 1 to 2, parotid volume, skewness, and kurtosis decreased ( P histogram parameters increased (all P histogram parameters. Early mean change rates for bilateral parotid SD and ADC max could predict late xerostomia degrees at seven months after radiotherapy (three months after time point 3) with AUC of 0.781 and 0.818 ( P = 0.014, 0.005, respectively). ADC histogram parameters were reproducible (intraclass correlation coefficient, 0.830 - 0.999). ADC histogram analysis could be used to evaluate radiation-induced parotid damage noninvasively, and predict late xerostomia degrees of NPC patients treated with radiotherapy.

  3. A Phase II Study of Submandibular Gland Transfer Prior to Radiation for Prevention of Radiation-Induced Xerostomia in Head and Neck Cancer (Rtog 0244)s

    Science.gov (United States)

    Jha, Naresh; Harris, Jonathan; Seikaly, Hadi; Jacobs, John R.; McEwan, AJB.; Thomas Robbins, K.; Grecula, John; Sharma, Anand K.; Ang, K. Kian

    2012-01-01

    Purpose We report the results of a phase II study to determine reproducibility of surgical technique of submandibular salivary gland transfer (SGT) for prevention of radiation (XRT) induced xerostomia in a multi-institutional setting and to assess severity of xerostomia. Methods and Materials Eligible patients had surgery for primary, neck dissection, and SGT followed by XRT during which the transferred salivary gland was shielded. IMRT, amifostine, and pilocarpine were not allowed, but postoperative chemotherapy was allowed. Each operation was reviewed by two and radiation by one reviewer. If 13 or more (out of 43) were “not per protocol”, then technique would be considered not reproducible as per study design. The secondary endpoint was the rate of acute xerostomia, Grade 2 or higher and a rate of ≤ 51% was acceptable. Results 44 of the total 49 patients were analyzable: male (81.8%), oropharynx (63.6%), stage IV (61.4%), median age 56.5 years. SGT was “per protocol” or with acceptable variation in 34 patients (77.3%) and XRT in 79.5%. 9 patients (20.9%) developed grade II acute xerostomia; 2 had grade 0 -1 xerostomia (4.7%) but started on amifostine/pilocarpine. These 11 patients (25.6%) were considered failures for the xerostomia endpoint. 13 patients have died; median follow-up for 31 surviving patients is 2.9 years. Two-year overall and disease-free survival rates are 76.4% and 71.7%, respectively. Conclusions the technique of submandibular salivary gland transfer procedure is reproducible in a multicenter setting. Seventy-four percent of patients had prevention of XRT induced acute xerostomia. PMID:22541957

  4. Acupuncture for the prevention of radiation-induced xerostomia in patients with head and neck cancer

    Directory of Open Access Journals (Sweden)

    Fabio do Prado Florence Braga

    2011-04-01

    Full Text Available The aim of this study was to evaluate the effectiveness of acupuncture in minimizing the severity of radiation-induced xerostomia in patients with head and neck cancer. A total of 24 consecutive patients receiving > 5000 cGy radiotherapy (RT involving the major salivary glands bilaterally were assigned to either the preventive acupuncture group (PA, n = 12, treated with acupuncture before and during RT, or the control group (CT, n = 12, treated with RT and not receiving acupuncture. After RT completion, clinical response was assessed in all patients by syalometry, measuring the resting (RSFR and stimulated (SSFR salivary flow rates, and by the visual analogue scale (VAS regarding dry mouth-related symptoms. Statistical analyses were performed with repeated-measures using a mixed-effect modeling procedure and analysis of variance. An alpha level of 0.05 was accepted for statistical significance. Although all patients exhibited some degree of impairment in salivary gland functioning after RT, significant differences were found between the groups. Patients in the PA group showed improved salivary flow rates (RSFR, SSFR; p < 0.001 and decreased xerostomia-related symptoms (VAS, p < 0.05 compared with patients in the CT group. Although PA treatment did not prevent the oral sequelae of RT completely, it significantly minimized the severity of radiation-induced xerostomia. The results suggest that acupuncture focused in a preventive approach can be a useful therapy in the management of patients with head and neck cancer undergoing RT.

  5. First-in-man mesenchymal stem cells for radiation-induced xerostomia (MESRIX): study protocol for a randomized controlled trial.

    Science.gov (United States)

    Grønhøj, Christian; Jensen, David H; Glovinski, Peter V; Jensen, Siri Beier; Bardow, Allan; Oliveri, Roberto S; Specht, Lena; Thomsen, Carsten; Darkner, Sune; Kiss, Katalin; Fischer-Nielsen, Anne; von Buchwald, Christian

    2017-03-07

    Salivary gland hypofunction and xerostomia are major complications following radiotherapy for head and neck cancer and may lead to debilitating oral disorders and impaired quality of life. Currently, only symptomatic treatment is available. However, mesenchymal stem cell (MSC) therapy has shown promising results in preclinical studies. Objectives are to assess safety and efficacy in a first-in-man trial on adipose-derived MSC therapy (ASC) for radiation-induced xerostomia. This is a single-center, phase I/II, randomized, placebo-controlled, double-blinded clinical trial. A total of 30 patients are randomized in a 1:1 ratio to receive ultrasound-guided, administered ASC or placebo to the submandibular glands. The primary outcome is change in unstimulated whole salivary flow rate. The secondary outcomes are safety, efficacy, change in quality of life, qualitative and quantitative measurements of saliva, as well as submandibular gland size, vascularization, fibrosis, and secretory tissue evaluation based on contrast-induced magnetic resonance imaging (MRI) and core-needle samples. The assessments are performed at baseline (1 month prior to treatment) and 1 and 4 months following investigational intervention. The trial is the first attempt to evaluate the safety and efficacy of adipose-derived MSCs (ASCs) in patients with radiation-induced xerostomia. The results may provide evidence for the effectiveness of ASC in patients with salivary gland hypofunction and xerostomia and deliver valuable information for the design of subsequent trials. EudraCT, Identifier: 2014-004349-29. Registered on 1 April 2015. ClinicalTrials.gov, Identifier: NCT02513238 . First received on 2 July 2015. The trial is prospectively registered.

  6. The Groningen Radiotherapy-Induced Xerostomia questionnaire : Development and validation of a new questionnaire

    NARCIS (Netherlands)

    Beetz, I.; Burlage, Fred; Bijl, H.P.; Chouvalova, Olga; Christianen, M.E.; Vissink, A.; van der Laan, B.F.; de Bock, G.H.; Langendijk, J.A.

    2010-01-01

    Purpose: The purpose of this study was to develop and validate a questionnaire (Groningen Radiotherapy-Induced Xerostomia (GRIX) questionnaire) that has the ability to distinguish between patient-rated xerostomia during day and night and can be used to evaluate the impact of emerging radiation

  7. Assessment of radiation-induced xerostomia: validation of the Italian version of the xerostomia questionnaire in head and neck cancer patients.

    Science.gov (United States)

    Pellegrino, Federica; Groff, Elena; Bastiani, Luca; Fattori, Bruno; Sotti, Guido

    2015-04-01

    Xerostomia is the most common acute and late side effect of radiation treatment for head and neck cancer. Affecting taste perception, chewing, swallowing and speech, xerostomia is also the major cause of decreased quality of life. The aims of this study were to validate the Italian translation of the self-reported eight-item xerostomia questionnaire (XQ) and determine its psychometric properties in patients treated with radiotherapy for head and neck cancer. An observational cross-sectional study was conducted in the Radiotherapy Unit of the Veneto Institute of Oncology - IOV in Padua. The XQ was translated according to international guidelines and filled out by 102 patients. Construct validity was assessed using principal component analysis, internal consistency using Cronbach's α coefficient and test-retest reliability at 1-month interval using the intraclass correlation coefficient (ICC). Criterion-related validity was evaluated to compare the Italian version of XQ with the European Organization for Research and Treatment of Cancer (EORTC) Core Quality-of-Life Questionnaire (QLQ-C30) and its Head and Neck Cancer Module (QLQ-H&N35). Cronbach's α for the Italian version of XQ was strong at α = 0.93, test-retest reliability was also strong (0.79) and factor analysis confirmed that the questionnaire was one-dimensional. Criterion-related validity was excellent with high association with the EORTC QLQ-H&N35 xerostomia and sticky saliva scales. The Italian version of XQ has excellent psychometric properties and can be used to evaluate the impact of emerging radiation delivery techniques aiming at preventing xerostomia.

  8. Effectiveness of Positioning Stents in Radiation-Induced Xerostomia in Patients with Tongue Carcinoma: A Randomized Controlled Trial.

    Science.gov (United States)

    Mall, Priyanka; Chand, Pooran; Singh, Balendra Pratap; Rao, Jitendra; Siddarth, Ramashanker; Srivastava, Kirti

    2016-01-01

    The aim of this study was to perform an objective and subjective evaluation of the efficacy of positioning stents in radiation-induced xerostomia in patients with tongue carcinoma. A total of 30 patients with tongue carcinoma and undergoing conventional radiotherapy were randomly assigned to control (n = 15) and study (n = 15) groups, without and with a positioning stent, respectively. Assessment of salivary output reduction was done before and after radiotherapy, at 3- and 6-month intervals, by measurement of unstimulated and stimulated salivary flow rates (objective evaluation). Xerostomia (subjective evaluation) was noted using six items from the Quality of Life Head and Neck Module (QLQ-H&N35) as proposed by the European Organization for Research and Treatment of Cancer. The significance level was set at .05. Mean unstimulated and stimulated salivary flow rates at 3- and 6-month intervals revealed significantly (P xerostomia and its symptoms.

  9. Effect of radiation-induced xerostomia on the human oral microflora. Report no. 12 (final), 1 Jul 1971-30 Jun 1976

    Energy Technology Data Exchange (ETDEWEB)

    Dreizen, S.; Brown, L.R.

    1976-06-30

    The caries-conducive impact of xerostomia was studied in 42 irradiated cancer patients. The radiation-induced xerostomia was paralleled by changes in the physical, microbial, biochemical, immunologic and dietary parameters of cariogenicity that collectively comprised an overwhelming caries challenge. Microbiologically, significant xerostomia-related increases in Strep. mutans, lactobacilli, staphylococci, yeasts and catalase-positive diphtheroids were accompanied by decreases in Strep. sanguis, bacteroides and fusobacteria in each of the 5 microenvironments tested. The scanty xerostomic saliva contained greater amounts of Na(+), Cl(-), Ca(++), Mg(++), Prot(-), lysozyme, IgA and IgG and considerably less HCO3(-). The increased concentrations of caries protective electrolytes and immunoproteins were negated by huge reductions in total daily saliva output. The xerostomia created caries challenge was almost completely neutralized by a preventive program of daily topical NaF applications and strict oral hygiene. (GRA)

  10. An evaluation of the effect of acupuncture on salivary pH and the Xerostomia Inventory score innasopharyngeal carcinoma patients with chemoradiation-induced xerostomia

    Science.gov (United States)

    Mihardja, H.; Susworo, R.; Srilestari, A.; Umri, H.

    2017-08-01

    Radiation-induced xerostomia is a distressing side-effect of radiation for nasopharyngeal carcinoma (NPC) treatment, commonly occurring in almost 100% of patients who undergo this procedure. It has been proposed that acupuncture can be used to treat radiation-induced xerostomia. To the best of our knowledge, the current study constitutes the first acupuncture research that has been conducted in Indonesia on xerostomia following chemo-irradiation in NPC patients. Twenty-five patients with xerostomia due tochemo-irradiation for NPC were divided randomly into three groups of auriculopuncture (group A), body acupuncture (group B), and combination acupuncture (group C). The subjects were evaluated according to Xerostomia Inventory scores before and after six and 12 acupuncture treatments. Salivary pH was determined before and after the 12th acupuncture treatment using a saliva check buffer kit. The success rate of acupuncture therapy in group A was 71-100%, 68-89% ingroup B, and 89-100% in group C (p > 0.050). The mean salivary pH increased after therapy from 6.18±0.60 to 6.83±4.48 in group A, from 6.16±0.54 to 6.67±2.26 in group B, and from 6.00±0.40 to 6.60±2.23 in group C (p > 0.050). After the 12th acupuncture therapy session, the mean Xerostomia Inventory score decreased from 35.70±5.14 prior to acupuncture therapy to 22.89±16.15 after it in group A, with corresponding decreases of 34.70±7.77 to 20.89±10.06 in group B, and of 36.70±5.25 to 21.44±8.97 in group C (p > 0.050). Auriculopuncture, body acupuncture, and combination acupuncture had the same effect of increasing salivary pH and decreasing the Xerostomia Inventory score in patients with xerostomia following chemo irradiation for NPC.

  11. Hermeneutic phenomenological interpretations of patients with head and neck neoplasm experiences living with radiation-induced xerostomia: the price to pay?

    Science.gov (United States)

    Charalambous, Andreas

    2014-10-01

    Patients with head and neck neoplasms often experience a number of persistent treatment related symptoms including xerostomia. The impact of xerostomia can be profound and wearing on the patients, hence negatively influencing their quality of life. The purpose of this study was to explore the in-depth experiences of the patients living with radiation-induced xerostomia. This was a hermeneutic phenomenological study inspired by the Philosophy of Paul Ricoeur. Research data were retrieved with individual narratives from 15 patients diagnosed with head and neck neoplasm that underwent radiotherapy. Interpretation proceeded through three phases: naïve reading, structural analysis and comprehensive understanding. Five themes consisting of ten sub-themes emerged from the narratives reflecting on the patients' lived experiences. The themes were "suffering of the body", "suffering of the person's world", "being helpless against xerostomia", "suffering of the mind" and "being alone". The comprehensive understanding disclosed new possibilities for being-in-the world in relation to living with xerostomia. The precedent consideration of xerostomia mainly as a physical side-effect of radiotherapy was outweighed by the social and psychological effects revealed by this study. These xerostomia's effects are inflicted on the patients with an obvious reflection on their perceived quality of life. The findings call upon a shift towards acknowledging the severity of xerostomia and the need to care for these patients holistically. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Acupuncture-Like Transcutaneous Electrical Nerve Stimulation Versus Pilocarpine in Treating Radiation-Induced Xerostomia: Results of RTOG 0537 Phase 3 Study.

    Science.gov (United States)

    Wong, Raimond K W; Deshmukh, Snehal; Wyatt, Gwen; Sagar, Stephen; Singh, Anurag K; Sultanem, Khalil; Nguyen-Tân, Phuc F; Yom, Sue S; Cardinale, Joseph; Yao, Min; Hodson, Ian; Matthiesen, Chance L; Suh, John; Thakrar, Harish; Pugh, Stephanie L; Berk, Lawrence

    2015-06-01

    This report presents the analysis of the RTOG 0537 multicenter randomized study that compared acupuncture-like transcutaneous stimulation (ALTENS) with pilocarpine (PC) for relieving radiation-induced xerostomia. Eligible patients were randomized to twice-weekly 20-minute ALTENS sessions for 24 sessions during 12 weeks or PC (5 mg 3 times daily for 12 weeks). The primary endpoint was the change in the University of Michigan Xerostomia-Related Quality of Life Scale (XeQOLS) scores from baseline to 9 months from randomization (MFR). Secondary endpoints included basal and citric acid primed whole salivary production (WSP), ratios of positive responders (defined as patients with ≥20% reduction in overall radiation-induced xerostomia symptom burden), and the presence of adverse events based on the Common Terminology Criteria for Adverse Events version 3. An intention-to-treat analysis was conducted. One hundred forty-eight patients were randomized. Only 96 patients completed the required XeQOLS and were evaluable at 9 MFR (representing merely 68.6% statistical power). Seventy-six patients were evaluable at 15 MFR. The median change in the overall XeQOLS in ALTENS and PC groups at 9 and 15 MFR were -0.53 and -0.27 (P=.45) and -0.6 and -0.47 (P=.21). The corresponding percentages of positive responders were 81% and 72% (P=.34) and 83% and 63% (P=.04). Changes in WSP were not significantly different between the groups. Grade 3 or less adverse events, mostly consisting of grade 1, developed in 20.8% of patients in the ALTENS group and in 61.6% of the PC group. The observed effect size was smaller than hypothesized, and statistical power was limited because only 96 of the recruited 148 patients were evaluable. The primary endpoint-the change in radiation-induced xerostomia symptom burden at 9 MFR-was not significantly different between the ALTENS and PC groups. There was significantly less toxicity in patients receiving ALTENS. Copyright © 2015 Elsevier Inc. All

  13. Acupuncture-Like Transcutaneous Electrical Nerve Stimulation Versus Pilocarpine in Treating Radiation-Induced Xerostomia: Results of RTOG 0537 Phase 3 Study

    International Nuclear Information System (INIS)

    Wong, Raimond K.W.; Deshmukh, Snehal; Wyatt, Gwen; Sagar, Stephen; Singh, Anurag K.; Sultanem, Khalil; Nguyen-Tân, Phuc F.; Yom, Sue S.; Cardinale, Joseph; Yao, Min; Hodson, Ian; Matthiesen, Chance L.; Suh, John; Thakrar, Harish; Pugh, Stephanie L.; Berk, Lawrence

    2015-01-01

    Purpose and Objectives: This report presents the analysis of the RTOG 0537 multicenter randomized study that compared acupuncture-like transcutaneous stimulation (ALTENS) with pilocarpine (PC) for relieving radiation-induced xerostomia. Methods and Materials: Eligible patients were randomized to twice-weekly 20-minute ALTENS sessions for 24 sessions during 12 weeks or PC (5 mg 3 times daily for 12 weeks). The primary endpoint was the change in the University of Michigan Xerostomia-Related Quality of Life Scale (XeQOLS) scores from baseline to 9 months from randomization (MFR). Secondary endpoints included basal and citric acid primed whole salivary production (WSP), ratios of positive responders (defined as patients with ≥20% reduction in overall radiation-induced xerostomia symptom burden), and the presence of adverse events based on the Common Terminology Criteria for Adverse Events version 3. An intention-to-treat analysis was conducted. Results: One hundred forty-eight patients were randomized. Only 96 patients completed the required XeQOLS and were evaluable at 9 MFR (representing merely 68.6% statistical power). Seventy-six patients were evaluable at 15 MFR. The median change in the overall XeQOLS in ALTENS and PC groups at 9 and 15 MFR were −0.53 and −0.27 (P=.45) and −0.6 and −0.47 (P=.21). The corresponding percentages of positive responders were 81% and 72% (P=.34) and 83% and 63% (P=.04). Changes in WSP were not significantly different between the groups. Grade 3 or less adverse events, mostly consisting of grade 1, developed in 20.8% of patients in the ALTENS group and in 61.6% of the PC group. Conclusions: The observed effect size was smaller than hypothesized, and statistical power was limited because only 96 of the recruited 148 patients were evaluable. The primary endpoint—the change in radiation-induced xerostomia symptom burden at 9 MFR—was not significantly different between the ALTENS and PC groups. There was significantly less

  14. Acupuncture-Like Transcutaneous Electrical Nerve Stimulation Versus Pilocarpine in Treating Radiation-Induced Xerostomia: Results of RTOG 0537 Phase 3 Study

    Energy Technology Data Exchange (ETDEWEB)

    Wong, Raimond K.W., E-mail: wongrai@hhsc.ca [McMaster University, Juravinski Cancer Centre, Hamilton, Ontario (Canada); Deshmukh, Snehal [NRG Oncology Statistics and Data Management Center, Philadelphia, Pennsylvania (United States); Wyatt, Gwen [Michigan State University, East Lansing, Michigan (United States); Sagar, Stephen [McMaster University, Juravinski Cancer Centre, Hamilton, Ontario (Canada); Singh, Anurag K. [Roswell Park Cancer Institute, Buffalo, New York (United States); Sultanem, Khalil [McGill University, Montreal, Quebec (Canada); Nguyen-Tân, Phuc F. [Centre Hospitalier de l' Université de Montréal-Hôpital Notre-Dame, Montreal, Quebec (Canada); Yom, Sue S. [University of California San Francisco, San Francisco, California (United States); Cardinale, Joseph [Yale-New Haven Hospital Saint Raphael Campus, New Haven, Connecticut (United States); Yao, Min [University Hospitals of Cleveland, Cleveland, Ohio (United States); Hodson, Ian [McMaster University, Juravinski Cancer Centre, Hamilton, Ontario (Canada); Matthiesen, Chance L. [University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma (United States); Suh, John [Cleveland Clinic Foundation, Cleveland, Ohio (United States); Thakrar, Harish [John H. Stroger, Jr. Hospital of Cook County MB-CCOP, Chicago, Illinois (United States); Pugh, Stephanie L. [NRG Oncology Statistics and Data Management Center, Philadelphia, Pennsylvania (United States); Berk, Lawrence [University of South Florida H. Lee Moffitt Cancer Center, Tampa, Florida (United States)

    2015-06-01

    Purpose and Objectives: This report presents the analysis of the RTOG 0537 multicenter randomized study that compared acupuncture-like transcutaneous stimulation (ALTENS) with pilocarpine (PC) for relieving radiation-induced xerostomia. Methods and Materials: Eligible patients were randomized to twice-weekly 20-minute ALTENS sessions for 24 sessions during 12 weeks or PC (5 mg 3 times daily for 12 weeks). The primary endpoint was the change in the University of Michigan Xerostomia-Related Quality of Life Scale (XeQOLS) scores from baseline to 9 months from randomization (MFR). Secondary endpoints included basal and citric acid primed whole salivary production (WSP), ratios of positive responders (defined as patients with ≥20% reduction in overall radiation-induced xerostomia symptom burden), and the presence of adverse events based on the Common Terminology Criteria for Adverse Events version 3. An intention-to-treat analysis was conducted. Results: One hundred forty-eight patients were randomized. Only 96 patients completed the required XeQOLS and were evaluable at 9 MFR (representing merely 68.6% statistical power). Seventy-six patients were evaluable at 15 MFR. The median change in the overall XeQOLS in ALTENS and PC groups at 9 and 15 MFR were −0.53 and −0.27 (P=.45) and −0.6 and −0.47 (P=.21). The corresponding percentages of positive responders were 81% and 72% (P=.34) and 83% and 63% (P=.04). Changes in WSP were not significantly different between the groups. Grade 3 or less adverse events, mostly consisting of grade 1, developed in 20.8% of patients in the ALTENS group and in 61.6% of the PC group. Conclusions: The observed effect size was smaller than hypothesized, and statistical power was limited because only 96 of the recruited 148 patients were evaluable. The primary endpoint—the change in radiation-induced xerostomia symptom burden at 9 MFR—was not significantly different between the ALTENS and PC groups. There was significantly less

  15. The Groningen Radiotherapy-Induced Xerostomia questionnaire: Development and validation of a new questionnaire

    International Nuclear Information System (INIS)

    Beetz, Ivo; Burlage, Fred R.; Bijl, Henk P.; Hoegen-Chouvalova, Olga; Christianen, Miranda E.M.C.; Vissink, Arjan; Laan, Bernard F.A.M. van der; Bock, Geertruida H. de; Langendijk, Johannes A.

    2010-01-01

    Purpose: The purpose of this study was to develop and validate a questionnaire (Groningen Radiotherapy-Induced Xerostomia (GRIX) questionnaire) that has the ability to distinguish between patient-rated xerostomia during day and night and can be used to evaluate the impact of emerging radiation delivery techniques aiming at prevention of xerostomia in more detail. Materials and methods: All questions in the GRIX were generated from an exhaustive list of relevant questions according to xerostomia as reported in the literature and reported by patients and health care providers. Finally the GRIX was reduced from 56 questions to a 14-item questionnaire, with four subscales; xerostomia during day and night and sticky saliva during day and night. 315 patients filled out 2936 questionnaires and the GRIX was evaluated by calculating Crohnbach's α for all subscales. Criterion validity was evaluated to compare the GRIX with patient-rated xerostomia scored with the EORTC QLQ-HN35 and physician-rated xerostomia, test-retest analysis and responsiveness were also tested. Results: Crohnbach's α varied for all subscales between 0.88 and 0.94. The GRIX scored well for criterion-related validity on all subscales with high correlations with the EORTC QLQ-HN35 xerostomia and sticky saliva scale as well with physician-rated toxicity scoring. No significant differences were found between test and retest score and the GRIX showed good responsiveness with different time points for all subscales. Conclusion: The GRIX is a validated questionnaire which can be used in future research focusing on patient-rated xerostomia and sticky saliva during day and night in relation with the impact of emerging radiation delivery techniques aiming at reduction of xerostomia.

  16. Phase II Results of RTOG 0537: A Phase II/III Study Comparing Acupuncture-like Transcutaneous Electrical Nerve Stimulation Versus Pilocarpine in Treating Early Radiation-Induced Xerostomia

    Science.gov (United States)

    Wong, Raimond K. W.; James, Jennifer L.; Sagar, Stephen; Wyatt, Gwen; Nguyen-Tân, Phuc Felix; Singh, Anurag K.; Lukaszczyk, Barbara; Cardinale, Francis; Yeh, Alexander M.; Berk, Lawrence

    2011-01-01

    Purpose This phase II component of a multi-institutional phase II/III randomized trial assessed the feasibility and preliminary efficacy of acupuncture-like transcutaneous electrical nerve stimulation (ALTENS) in reducing radiation-induced xerostomia. Methods Head and neck cancer patients who were 3–24 months from completing radiotherapy ± chemotherapy (RT±C) and experiencing xerostomia symptoms with basal whole saliva production ≥0.1 ml/min and without recurrence were eligible. Patients received twice weekly ALTENS sessions (24 over 12 weeks) using a Codetron™ unit. The primary objective assessed the feasibility of ALTENS treatment. A patient was considered compliant if 19/24 ALTENS were delivered, with a targeted 85% compliance rate. Secondary objectives measured treatment-related toxicities and ALTENS effect on overall radiation-induced xerostomia burden using the University of Michigan Xerostomia-Related Quality of Life Scale (XeQOLS). Results Of 48 accrued patients, 47 were evaluable. Median age was 60 years; 84% were male, 70% completed RT±C for > 12 months and 21% had received prior pilocarpine. All ALTENS sessions were completed in 34 patients, but 9 and 1 completed 20–23 and 19 sessions respectively, representing a 94% total compliance rate. 6-month XeQOLS scores were available for 35 patients; 30 (86%) achieved a positive treatment response with a mean reduction of 35.9% (SD 36.1). Five patients developed grade 1–2 gastrointestinal toxicity and one had grade 1 pain event. Conclusions ALTENS treatment for radiation-induced xerostomia can be uniformly delivered in a cooperative multicenter setting and has possible beneficial treatment response. Given these results, the phase III component of this study was initiated. PMID:22252927

  17. Quantitative assessment of salivary gland function by radioisotopic scanning in a randomized trial of pilocarpine for prevention of radiation Induced Xerostomia

    International Nuclear Information System (INIS)

    Fard-Esfahani, A.; Modarress-Mosalla, M.; Haddad, P.; Eftekhari, M.; Saghari, M.

    2001-01-01

    Radioisotope scanning is the best method for objective assessment of salivary gland function. Thus, it was used in a randomized trial of concomitant pilocarpine for assessment of radiation-induced xerostomia, in addition to subjective evaluation by an approved questionnaire and objective standard xerostomia grading. Patients randomized in a placebo-controlled trial of pilocarpine concurrent with irradiation for prevention of radiation-induced xerostomia were evaluated by salivary gland scintigraphy immediately before and 6 months after the end of head and neck radiotherapy. Salivary gland function was measured by ejection fraction (E F) of Technetium-99 m pertechnetate. The mean values for pre-and post-radiotherapy scans were calculated and compared. Also post-radiotherapy scan findings in the two groups of pilocarpine and placebo were compared using the Student's t-test. In addition, comparison was made between the scan results and the subjective findings and objective grading s.Twenty patients underwent the pre-radiotherapy salivary scintigraphy, and also 20 post-radiotherapy scans were performed . Mean parotid E F was 60.85% in the pre-radiotherapy and 9.08% in the post-radiotherapy scans (p<0.01). The means for submandibular glands in the pre-and post-radiotherapy scans were 41% and 11.2%, respectively (p<0.01). Also the mean E F was 14.5% in the pilocarpine group and 3.65 in the placebo group for parotid glands (p=0.07) and 18.3% and 4.1% respectively for submandibular glands (p<0.05). The salivary scans confirmed the subjective and objective xerostomia findings. Salivary gland scintigraphy is a valuable method for evaluation of xerostomia after head and neck radiotherapy, quantitatively demonstrating the protective effect of pilocarpine compared to placebo on salivary glands

  18. 3D MR Sialography as a Tool to Investigate Radiation-Induced Xerostomia: Feasibility Study

    International Nuclear Information System (INIS)

    Astreinidou, Eleftheria; Roesink, Judith M.; Raaijmakers, Cornelis P.J.; Bartels, Lambertus W.; Witkamp, Theo D.; Lagendijk, Jan J.W.; Terhaard, Chris H.J.

    2007-01-01

    Purpose: To evaluate whether magnetic-resonance (MR) sialography can be used to investigate radiation-induced xerostomia. Preradiotherapy (pre-RT) and postradiotherapy (post-RT) MR sialographic images of the major salivary ducts (parotid and submandibular) were compared. Methods and Materials: Magnetic-resonance sialography was performed pre-RT, and 6 weeks and 6 months post-RT on 9 patients with T1-4N0-2M0 naso- or oropharyngeal tumors, on a 1.5-T MR scanner. Patients were positioned in the scanner, using a radiotherapy immobilization mask. Image registration of the MR sialograms pre- and post-RT with each other and with the CT and consequently the dose distribution was performed. A categorical scoring system was used to compare the visibility of ducts pre-RT and post-RT. Results: Good-quality MR sialographic images were obtained, and image registration was successful in all cases. The visibility score of the parotid ducts and submandibular ducts was reduced at 6 weeks post-RT, which means that the full trajectory of the salivary ducts, from the intraglandular space to the mouth cavity, was only partially visualized. For some of the parotid ducts, the visibility score improved at 6 months post-RT, but not for the submandibular ducts. The mean dose for the parotid glands was 35 Gy (1 standard deviation [SD] 3 Gy), and for the submandibular glands it was 62 Gy (SD, 8 Gy). Conclusion: Three-dimensional MR sialography is a promising approach for investigating xerostomia, because radiation-induced changes to the saliva content of the ducts can be visualized

  19. The effectiveness of thyme honey for the management of treatment-induced xerostomia in head and neck cancer patients: A feasibility randomized control trial.

    Science.gov (United States)

    Charalambous, Andreas; Lambrinou, Ekaterini; Katodritis, Nicos; Vomvas, Dimitrios; Raftopoulos, Vasilios; Georgiou, Morpho; Paikousis, Lefkios; Charalambous, Melanie

    2017-04-01

    Radiation-induced xerostomia is one of the most common side effects that head and neck cancer patients experience during and after treatment. Despite the various methods for the prevention and treatment of radiation-induced xerostomia, it remains highly prevalent among patients treated for head and neck cancers negatively influencing their lives. The purpose of this study was to evaluate the effectiveness of thyme honey as a means for managing radiation-induced xerostomia. This was a parallel randomised controlled trial with two equal arms, the experimental arm (thyme honey) and the control arm (saline). 72 head and neck cancer patients receiving radiotherapy or/and chemotherapy or/and surgery were recruited in a specialised cancer centre. Patients in both arms followed the same administration protocol with thyme honey and saline respectively. Identical assessments at baseline, 1 month and 6 months following completion of the intervention were performed in both arms including the National Cancer Institute (NCI) xerostomia scale and the Xerostomia Questionnaire (XQ) additionally to weekly oral clinical assessments. The ClinicalTrials.gov Identifier for this study is NCT01465308. Linear Mixed Models revealed the statistically significant effect of the intervention on xerostomia (F = 8.474 p xerostomia. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Reduction of radiation-induced xerostomia in nasopharyngeal carcinoma using CT simulation with laser patient marking and three-field irradiation technique

    International Nuclear Information System (INIS)

    Nishioka, Takeshi; Shirato, Hiroki; Arimoto, Takuro; Kaneko, Masanori; Kitahara, Toshihiro; Oomori, Keiichi; Yasuda, Motoyuki; Fukuda, Satoshi; Inuyama, Yukio; Miyasaka, Kazuo

    1997-01-01

    Purpose: Tumor control and reduction of postirradiation xerostomia in patients with nasopharyngeal carcinoma (NPC) using the three-field irradiation technique based on the CT-based simulation with laser patient marking was investigated. Methods and Materials: Seventy-eight patients with NPC were consecutively treated between 1983 and 1993. In 33 patients treated before 1987, target volume was determined using a conventional x-ray simulator with a reference of CT images, and the primary site was treated by the conventional parallel-opposed two-field technique (Group I). In 45 patients treated from 1987, target volume was determined using a CT simulator slice by slice, the treatment field was projected onto the patient's skin by a laser beam projector mounted on a C-arm, and the primary site was irradiated by a three-fields (anterior and bilateral) technique (Group II). In Group II, the shape of each field was determined using a beam's eye view to reduce the dose to the bilateral parotid glands. The three-field technique reduced the dose to the superficial lobe of parotid gland to about two-thirds of the dose given by the two-field technique. Radiation-induced xerostomia was evaluated by clinical symptoms and radio-isotope sialography. Results: The 5-year survival rate and disease-free survival rate were 46.6 and 31.2% in Group I, and 46.8 and 46.5% in Group II. A large variation in the volume of parotid glands were demonstrated, ranging from 9 cm 3 to 61 cm 3 among patients treated with CT simulation. Forty percent of the patients in Group II showed no or mild xerostomia, whereas all of the patients in Group I showed moderate to severe xerostomia (p < 0.01). The radioisotope sialography study showed that the mean secretion ratio by acid stimulation was improved from 3.8% in the Group I to 15.2% in the Group II (p < 0.01). Conclusions: CT simulation was useful to determine the size and shape of each field to reduce the dose to the parotid gland, of which size varies

  1. Xerostomia induced by radiotherapy: an overview of the physiopathology, clinical evidence, and management of the oral damage

    Directory of Open Access Journals (Sweden)

    Pinna R

    2015-02-01

    Full Text Available Roberto Pinna,1 Guglielmo Campus,2 Enzo Cumbo,3 Ida Mura,1 Egle Milia2 1Department of Biomedical Science, 2Department of Surgery, Microsurgery and Medicine, University of Sassari, Sassari, 3Department of Dental Science, University of Palermo, Palermo, Italy Background: The irradiation of head and neck cancer (HNC often causes damage to the salivary glands. The resulting salivary gland hypofunction and xerostomia seriously reduce the patient’s quality of life. Purpose: To analyze the literature of actual management strategies for radiation-induced hypofunction and xerostomia in HNC patients. Methods: MEDLINE/PubMed and the Cochrane Library databases were electronically evaluated for articles published from January 1, 1970, to June 30, 2013. Two reviewers independently screened and included papers according to the predefined selection criteria. Results: Sixty-one articles met the inclusion criteria. The systematic review of the literature suggests that the most suitable methods for managing the clinical and pathophysiological consequences of HNC radiotherapy might be the pharmacological approach, for example, through the use of cholinergic agonists when residual secretory capacity is still present, and the use of salivary substitutes. In addition, a modified diet and the patient’s motivation to enhance oral hygiene can lead to a significant improvement. Conclusion: Radiation-induced xerostomia could be considered a multifactorial disease. It could depend on the type of cancer treatment and the cumulative radiation dose to the gland tissue. A preventive approach and the correct treatment of the particular radiotherapeutic patient can help to improve the condition of xerostomia. Keywords: radiation-induced xerostomia, salivary gland hypofunction, management strategies

  2. Cost-effectiveness landscape analysis of treatments addressing xerostomia in patients receiving head and neck radiation therapy

    Science.gov (United States)

    Sasportas, Laura S.; Hosford, Andrew T.; Sodini, Maria A.; Waters, Dale J.; Zambricki, Elizabeth A.; Barral, Joëlle K.; Graves, Edward E.; Brinton, Todd J.; Yock, Paul G.; Le, Quynh-Thu; Sirjani, Davud

    2014-01-01

    Head and neck (H&N) radiation therapy (RT) can induce irreversible damage to the salivary glands thereby causing long-term xerostomia or dry mouth in 68%–85% of the patients. Not only does xerostomia significantly impair patients’ quality-of-life (QOL) but it also has important medical sequelae, incurring high medical and dental costs. In this article, we review various measures to assess xerostomia and evaluate current and emerging solutions to address this condition in H&N cancer patients. These solutions typically seek to accomplish 1 of the 4 objectives: (1) to protect the salivary glands during RT, (2) to stimulate the remaining gland function, (3) to treat the symptoms of xerostomia, or (4) to regenerate the salivary glands. For each treatment, we assess its mechanisms of action, efficacy, safety, clinical utilization, and cost. We conclude that intensity-modulated radiation therapy is both the most widely used prevention approach and the most cost-effective existing solution and we highlight novel and promising techniques on the cost-effectiveness landscape. PMID:23643579

  3. Drug induced xerostomia in elderly individuals: An institutional study

    Directory of Open Access Journals (Sweden)

    Shishir Ram Shetty

    2012-01-01

    Full Text Available Introduction : With better health care facilities and nutritional levels the average life expectancy of Indian population has been on the rise over the years. Most of the geriatric population is under long-term medication. Aim : The aim of this study was to evaluate the synergistic effect of multiple xerostomia drugs. Materials and Methods : Unstimulated saliva was measured in 60 geriatric patients, and xerostomia questionnaire and quality-of-life scale were also administered. Results : There was a very highly significant reduction in the salivary flow rates of patients under multiple xerostomia-inducing drugs. Conclusion : The synergistic effect of the xerostomia inducing medication could be the possible factor responsible for reduced salivary flow in elderly individuals using such drugs

  4. A systematic review of salivary gland hypofunction and xerostomia induced by cancer therapies

    DEFF Research Database (Denmark)

    Jensen, S.B.; Pedersen, A.M.L.; Vissink, A.

    2010-01-01

    submandibular and minor salivary glands, as these glands are major contributors to moistening of oral tissues. Other cancer treatments also induce salivary gland hypofunction, although to a lesser severity, and in the case of chemotherapy and immunotherapy, the adverse effect is temporary. Fields of sparse...... met by 184 articles covering salivary gland hypofunction and xerostomia induced by conventional, 3D conformal radiotherapy or intensity-modulated radiotherapy in head and neck cancer patients, cancer chemotherapy, total body irradiation/hematopoietic stem cell transplantation, radioactive iodine...... treatment, and immunotherapy. Salivary gland hypofunction and xerostomia are induced by radiotherapy in the head and neck region depending on the cumulative radiation dose to the gland tissue. Treatment focus should be on optimized/new approaches to further reduce the dose to the parotids, and particularly...

  5. Trismus, xerostomia and nutrition status in nasopharyngeal carcinoma survivors treated with radiation.

    Science.gov (United States)

    Chen, Y-J; Chen, S-C; Wang, C-P; Fang, Y-Y; Lee, Y-H; Lou, P-J; Ko, J-Y; Chiang, C-C; Lai, Y-H

    2016-05-01

    The aims of the study were to: (1) examine levels of trismus, xerostomia and nutritional status; (2) compare levels of trismus, xerostomia and nutritional status in patients with nasopharyngeal carcinoma (NPC) receiving different types of radiation modalities; and (3) identify factors related to NPC survivors' risk status for malnutrition and existing malnutrition. A cross-sectional study with consecutive sampling was conducted. NPC survivors were recruited from otolaryngology/oncology outpatient clinics in a medical centre in Northern Taiwan. Study measures included (1) Mandibular Function Impairment Questionnaire, (2) Xerostomia Questionnaire, (3) Mini Nutrition Assessment, (4) Hospital Anxiety and Depression Scale - Depression subscale, and (5) Symptom Severity Scale. A total of 110 subjects were recruited. Those receiving intensity-modulated radiation therapy had less trismus and xerostomia than patients receiving two-dimensional radiation therapy. Patients with female gender, advanced stage, completion of treatments within 1 year, higher levels of depression, more severe trismus and higher symptom severity tended to have malnutrition or were at risk of malnutrition. Trismus and xerostomia are long-term problems in some NPC survivors and may contribute to malnutrition. To better manage a patient's trismus and xerostomia and to enhance nutritional status, clinicians should develop a patient-specific care programme based on careful assessment and targeted measures to improve oral function and insure adequate nutritional intake. © 2014 John Wiley & Sons Ltd.

  6. Randomized controlled trial of acupuncture for prevention of radiation-induced xerostomia among patients with nasopharyngeal carcinoma

    Science.gov (United States)

    Meng, Zhiqiang; Garcia, M. Kay; Hu, Chaosu; Chiang, Joseph; Chambers, Mark; Rosenthal, David I.; Peng, Huiting; Zhang, Ying; Zhao, Qi; Zhao, Genming; Liu, Luming; Spelman, Amy; Palmer, J. Lynn; Wei, Qi; Cohen, Lorenzo

    2011-01-01

    Background Xerostomia (dry mouth) after head/neck radiation is a common problem among cancer patients and available treatments are of little benefit. The objective of this trial was to determine if acupuncture can prevent xerostomia among head/neck patients undergoing radiotherapy. Methods A randomized, controlled trial among patients with nasopharyngeal carcinoma was conducted comparing acupuncture to standard care. Participants were treated at Fudan University Shanghai Cancer Center, Shanghai, China. Forty patients were randomized to acupuncture treatment and 46 to standard care. Patients were treated 3 times/week on the same days they received radiotherapy. Subjective measures included the Xerostomia Questionnaire (XQ) and MD Anderson Symptom Inventory for Head/Neck (MDASI-HN). Objective measures were unstimulated and stimulated whole salivary flow rates (UWSFR; SSFR). Patients were followed for 6 months after the end of radiotherapy. Results XQ scores for acupuncture were statistically significantly lower than controls starting in week 3 through the 6-months(P=0.003 at week3, all other P’s xerostomia and improved QOL. PMID:22072272

  7. Evaluation of effect of transcutaneous electrical nerve stimulation on salivary flow rate in radiation induced xerostomia patients: a pilot study.

    Science.gov (United States)

    Lakshman, Anusha Rangare; Babu, G Subhas; Rao, Suresh

    2015-01-01

    Xerostomia is a common sequel in patients undergoing irradiation of malignant tumors of the head and neck. Palliative treatments of xerostomia like topical agents such as ice-chips, saliva substitutes, systemic sialogogues like pilocarpine and cevimeline work well for some patients. Electrostimulation was studied in the past and showed moderate promise but never became part of the mainstream therapy for better management of xerostomia patients. The aim of the following study is to evaluate the effectiveness of a transcutaneous electrical nerve stimulation (TENS) unit in stimulating the whole salivary flow rate in radiation induced xerostomia patients. A total of 40 subjects were included in the study. The study group consisted of 30 individuals and was divided into Group S1 (n = 20), which was further subdivided into Group S1A (n = 10) subjects complaining of dry mouth who were undergoing head and neck radiotherapy with TENS stimulation during the commencement of radiotherapy, on the 3 rd , 6 th week and after a month of completion of radiotherapy and Group S1B (n = 10) with TENS stimulation daily during the full course of radiotherapy and Group S2 (n = 10) subjects complaining of dry mouth who had undergone head and neck radiotherapy that ended 1 month prior to their entry into the study. The control group (n = 10) consisted of healthy individuals not complaining of dry mouth and who have not undergone head and neck radiotherapy. Whole saliva was collected without stimulation for 10 min and after electrostimulation with TENS unit for additional 10 min in a graduated test tube. The results were statistically analyzed using Mann-Whitney U-test and Kruskal-Wallis's test. The data analysis revealed that control and S1B group showed increased salivary flow rate after stimulation by TENS therapy compared with the unstimulated salivary flow, whereas in S1A and S2 group it was found to be statistically non-significant. The present study gave us an insight about the

  8. SU-F-J-218: Predicting Radiation-Induced Xerostomia by Dosimetrically Accounting for Daily Setup Uncertainty During Head and Neck IMRT

    International Nuclear Information System (INIS)

    Park, S; Quon, H; McNutt, T; Lee, J; Plishker, W; Shekhar, R

    2016-01-01

    Purpose: To determine if the accumulated parotid dosimetry using planning CT to daily CBCT deformation and dose re-calculation can predict for radiation-induced xerostomia. Methods: To track and dosimetrically account for the effects of anatomical changes on the parotid glands, we propagated physicians’ contours from planning CT to daily CBCT using a deformable registration with iterative CBCT intensity correction. A surface mesh for each OAR was created with the deformation applied to the mesh to obtain the deformed parotid volumes. Daily dose was computed on the deformed CT and accumulated to the last fraction. For both the accumulated and the planned parotid dosimetry, we tested the prediction power of different dosimetric parameters including D90, D50, D10, mean, standard deviation, min/max dose to the combined parotids and patient age to severe xerostomia (NCI-CTCAE grade≥2 at 6 mo follow-up). We also tested the dosimetry to parotid sub-volumes. Three classification algorithms, random tree, support vector machine, and logistic regression were tested to predict severe xerostomia using a leave-one-out validation approach. Results: We tested our prediction model on 35 HN IMRT cases. Parameters from the accumulated dosimetry model demonstrated an 89% accuracy for predicting severe xerostomia. Compared to the planning dosimetry, the accumulated dose consistently demonstrated higher prediction power with all three classification algorithms, including 11%, 5% and 30% higher accuracy, sensitivity and specificity, respectively. Geometric division of the combined parotid glands into superior-inferior regions demonstrated ∼5% increased accuracy than the whole volume. The most influential ranked features include age, mean accumulated dose of the submandibular glands and the accumulated D90 of the superior parotid glands. Conclusion: We demonstrated that the accumulated parotid dosimetry using CT-CBCT registration and dose re-calculation more accurately predicts for

  9. SU-F-J-218: Predicting Radiation-Induced Xerostomia by Dosimetrically Accounting for Daily Setup Uncertainty During Head and Neck IMRT

    Energy Technology Data Exchange (ETDEWEB)

    Park, S; Quon, H; McNutt, T; Lee, J [Johns Hopkins University, Baltimor, MD (United States); Plishker, W [IGI Technologies, Inc., College Park, MD (United States); Shekhar, R [IGI Technologies, Inc., College Park, MD (United States); Children’s National Medical Center, Washington, DC (United States)

    2016-06-15

    Purpose: To determine if the accumulated parotid dosimetry using planning CT to daily CBCT deformation and dose re-calculation can predict for radiation-induced xerostomia. Methods: To track and dosimetrically account for the effects of anatomical changes on the parotid glands, we propagated physicians’ contours from planning CT to daily CBCT using a deformable registration with iterative CBCT intensity correction. A surface mesh for each OAR was created with the deformation applied to the mesh to obtain the deformed parotid volumes. Daily dose was computed on the deformed CT and accumulated to the last fraction. For both the accumulated and the planned parotid dosimetry, we tested the prediction power of different dosimetric parameters including D90, D50, D10, mean, standard deviation, min/max dose to the combined parotids and patient age to severe xerostomia (NCI-CTCAE grade≥2 at 6 mo follow-up). We also tested the dosimetry to parotid sub-volumes. Three classification algorithms, random tree, support vector machine, and logistic regression were tested to predict severe xerostomia using a leave-one-out validation approach. Results: We tested our prediction model on 35 HN IMRT cases. Parameters from the accumulated dosimetry model demonstrated an 89% accuracy for predicting severe xerostomia. Compared to the planning dosimetry, the accumulated dose consistently demonstrated higher prediction power with all three classification algorithms, including 11%, 5% and 30% higher accuracy, sensitivity and specificity, respectively. Geometric division of the combined parotid glands into superior-inferior regions demonstrated ∼5% increased accuracy than the whole volume. The most influential ranked features include age, mean accumulated dose of the submandibular glands and the accumulated D90 of the superior parotid glands. Conclusion: We demonstrated that the accumulated parotid dosimetry using CT-CBCT registration and dose re-calculation more accurately predicts for

  10. Timing of pilocarpine treatment during head and neck radiotherapy: concomitant administration reduces xerostomia better than post-radiation pilocarpine

    International Nuclear Information System (INIS)

    Zimmerman, Robert P.; Mark, Rufus J.; Juillard, Guy F.

    1996-01-01

    Purpose: To study whether oral pilocarpine administration during and three months after head and neck radiotherapy can prevent or reduce the expected post-radiation xerostomia. This regimen was compared to no treatment and to post-radiotherapy pilocarpine administration, which has previously been shown to reduce symptoms of xerostomia in several randomized trials. Methods: Xerostomia assessments were performed using a visual analog scale xerostomia questionnaire that measures oral dryness, oral comfort, difficulty with sleep, speech and eating. Higher scores indicate less xerostomia. All the patients had all major salivary glands in the initial field treated to ≥ 4,500 cGy. The concomitant pilocarpine group received 5 mg pilocarpine q.i.d. beginning on day one of radiotherapy and continuing for 3 months after completion of radiation. The control group had their baseline xerostomia measured prior to receiving pilocarpine. They subsequently took 5 mg pilocarpine t.i.d. for one month at which time they underwent a second xerostomia assessment. Xerostomia scores for each group were averaged and compared using the Student's t-test. Results: Seventeen patients who received pilocarpine during head and neck irradiation were compared to 12 post-radiotherapy patients who had not yet taken pilocarpine and the same patients after taking pilocarpine for one month. The mean intervals between completion of radiation and evaluation of xerostomia were 16 months for the control group and 17 months for the pilocarpine treated groups. The primary tumor sites treated as well as the total tumor doses were equivalent between the groups. Only one of the pilocarpine treated patients was still taking pilocarpine at the time of evaluation. Results are shown. For each component of xerostomia measured as well as the composite of all components, the group that had received pilocarpine during radiation had significantly less xerostomia than the no pilocarpine group (p<0.01 for each). Post

  11. Diagnostic accuracy of ultrasonic histogram features to evaluate radiation toxicity of the parotid glands: a clinical study of xerostomia following head-and-neck cancer radiotherapy.

    Science.gov (United States)

    Yang, Xiaofeng; Tridandapani, Srini; Beitler, Jonathan J; Yu, David S; Chen, Zhengjia; Kim, Sungjin; Bruner, Deborah W; Curran, Walter J; Liu, Tian

    2014-10-01

    To investigate the diagnostic accuracy of ultrasound histogram features in the quantitative assessment of radiation-induced parotid gland injury and to identify potential imaging biomarkers for radiation-induced xerostomia (dry mouth)-the most common and debilitating side effect after head-and-neck radiotherapy (RT). Thirty-four patients, who have developed xerostomia after RT for head-and-neck cancer, were enrolled. Radiation-induced xerostomia was defined by the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer morbidity scale. Ultrasound scans were performed on each patient's parotids bilaterally. The 34 patients were stratified into the acute-toxicity groups (16 patients, ≤ 3 months after treatment) and the late-toxicity group (18 patients, > 3 months after treatment). A separate control group of 13 healthy volunteers underwent similar ultrasound scans of their parotid glands. Six sonographic features were derived from the echo-intensity histograms to assess acute and late toxicity of the parotid glands. The quantitative assessments were compared to a radiologist's clinical evaluations. The diagnostic accuracy of these ultrasonic histogram features was evaluated with the receiver operating characteristic (ROC) curve. With an area under the ROC curve greater than 0.90, several histogram features demonstrated excellent diagnostic accuracy for evaluation of acute and late toxicity of parotid glands. Significant differences (P xerostomia monitoring and assessment. Copyright © 2014 AUR. Published by Elsevier Inc. All rights reserved.

  12. Randomized Trial of Vitamin C/E Complex for Prevention of Radiation-Induced Xerostomia in Patients with Head and Neck Cancer.

    Science.gov (United States)

    Chung, Man Ki; Kim, Do Hun; Ahn, Yong Chan; Choi, Joon Young; Kim, Eun Hye; Son, Young-Ik

    2016-09-01

    The present study was conducted to determine the preventive efficacy of vitamin C/E complex supplementation for radiotherapy (RT)-induced xerostomia in patients with head and neck cancer. Prospective, double-blinded, randomized, placebo-controlled study. A single tertiary referral institution. The trial group (n = 25) received antioxidant supplements (100 IU of vitamin E + 500 mg of vitamin C) twice per day during RT, while the control group (n = 20) received an identical placebo. Pre-RT and 1 and 6 months post-RT, patient-reported xerostomia questionnaires, observer-rated xerostomia score, and salivary scintigraphy were serially obtained to compare xerostomia severity between the 2 groups. The trial group showed greater improvements in xerostomia questionnaire and score at 6 months post-RT when compared with those at 1 month post-RT (P = .007 and .008, respectively). In contrast, the control group showed no changes between 1 and 6 months post-RT. By salivary scintigraphy, there was no difference in maximal accumulation or ejection fraction between the 2 groups. However, the trial group maintained significantly better oral indices at the prestimulatory (P = .01) and poststimulatory (P = .009) stages at 1 month post-RT, compared with the control group. At the final follow-up, there was no difference in overall survival and disease-free survival between the 2 groups. Our data suggest that short-term supplementation with an antioxidant vitamin E/C complex exerts a protective effect against RT-induced xerostomia. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2016.

  13. Sham-controlled, randomized, feasibility trial of acupuncture for prevention of radiation-induced xerostomia among patients with nasopharyngeal carcinoma

    Science.gov (United States)

    Meng, Zhiqiang; Garcia, M. Kay; Hu, Chaosu; Chiang, Joseph; Chambers, Mark; Rosenthal, David I.; Peng, Huiting; Wu, Caijun; Zhao, Qi; Zhao, Genming; Liu, Luming; Spelman, Amy; Palmer, J. Lynn; Wei, Qi; Cohen, Lorenzo

    2013-01-01

    Background Xerostomia (dry mouth) after head/neck radiation is a common problem among cancer patients. Quality of life (QOL) is impaired, and available treatments are of little benefit. This trial determined the feasibility of conducting a sham-controlled trial of acupuncture and whether acupuncture could prevent xerostomia among head/neck patients undergoing radiotherapy. Methods A sham controlled, feasibility trial was conducted at Fudan University Shanghai Cancer Center, Shanghai, China among patients with nasopharyngeal carcinoma undergoing radiotherapy. To determine feasibility of a sham procedure, 23 patients were randomized to real acupuncture (N = 11) or to sham acupuncture (N = 12). Patients were treated 3 times/week during their course of radiotherapy. Subjective measures were the Xerostomia Questionnaire (XQ) and MD Anderson Symptom Inventory for Head and Neck Cancer (MDASI-HN). Objective measures were unstimulated whole salivary flow rates (UWSFR) and stimulated salivary flow rates (SSFR). Patients were followed for 1 month after radiotherapy. Results XQ scores for acupuncture were significantly lower than sham controls starting in week 3 and lasted through the 1-month follow-up (all P’s xerostomia symptoms and improved QOL when compared with sham acupuncture. Large-scale, multi-center, randomized, placebo-controlled trials are now needed. PMID:22285177

  14. Clinical management of salivary gland hypofunction and xerostomia in head-and-neck cancer patients: successes and barriers

    DEFF Research Database (Denmark)

    Vissink, A.; Mitchell, J.B.; Baum, B.J.

    2010-01-01

    , and issues contributing to the clinical management of salivary gland hypofunction and xerostomia. These include ways to (1) prevent or minimize radiation injury of salivary gland tissue, (2) manage radiation-induced hyposalivation and xerostomia, and (3) restore the function of salivary gland tissue damaged......The most significant long-term complication of radiotherapy in the head-and-neck region is hyposalivation and its related complaints, particularily xerostomia. This review addresses the pathophysiology underlying irradiation damage to salivary gland tissue, the consequences of radiation injury...

  15. Clinical Management of Salivary Gland Hypofunction and Xerostomia in Head-and-Neck Cancer Patients: Successes and Barriers

    International Nuclear Information System (INIS)

    Vissink, Arjan; Mitchell, James B.; Baum, Bruce J.; Limesand, Kirsten H.; Jensen, Siri Beier; Fox, Philip C.; Elting, Linda S.; Langendijk, Johannes A.; Coppes, Robert P.; Reyland, Mary E.

    2010-01-01

    The most significant long-term complication of radiotherapy in the head-and-neck region is hyposalivation and its related complaints, particularily xerostomia. This review addresses the pathophysiology underlying irradiation damage to salivary gland tissue, the consequences of radiation injury, and issues contributing to the clinical management of salivary gland hypofunction and xerostomia. These include ways to (1) prevent or minimize radiation injury of salivary gland tissue, (2) manage radiation-induced hyposalivation and xerostomia, and (3) restore the function of salivary gland tissue damaged by radiotherapy.

  16. Xerostomia induced by radiotherapy

    Directory of Open Access Journals (Sweden)

    Alimi D

    2015-08-01

    Full Text Available David Alimi Department of Anesthesiology, University of Pittsburgh Medical Center, Pittsburgh, PA, USAWe read with great interest the excellent review on xerostomia induced by radiotherapy, by Pinna et al.1 The authors should be congratulated for a very detailed review of the physiopathology, clinical symptoms, and therapeutic management of an extremely difficult condition. Although we agree that the use of anticholinergic medication represents treatment, it requires the patient to have residual salivary gland function. Unfortunately, it is well established that in most cases radiotherapy destroys most of the salivary gland and associated salivary secretions.     

  17. Evaluation of effect of transcutaneous electrical nerve stimulation on salivary flow rate in radiation induced xerostomia patients: A pilot study

    Directory of Open Access Journals (Sweden)

    Anusha Rangare Lakshman

    2015-01-01

    Conclusion: The present study gave us an insight about the effectiveness of TENS therapy in stimulating salivary flow in healthy subjects and it is very effective when used in conjunction with radiation therapy by reducing the side-effects of radiation therapy. Hence, TENS therapy can be used as an adjunctive method for the treatment of xerostomia along with other treatment modalities.

  18. Effectiveness of malic acid 1% in patients with xerostomia induced by antihypertensive drugs

    Science.gov (United States)

    Guardia, Javier; Aguilar-Salvatierra, Antonio; Cabrera-Ayala, Maribel; Maté-Sánchez de-Val, José E.; Calvo-Guirado, José L.

    2013-01-01

    Objectives: Assessing the clinical effectiveness of a topical sialogogue on spray (malic acid, 1%) in the treatment of xerostomia induced by antihypertensive drugs. Study Design: This research has been carried out through a randomized double-blind clinical trial. 45 patients suffering from hypertensive drugs-induced xerostomia were divided into 2 groups: the first group (25 patients) received a topical sialogogue on spray (malic acid, 1%) whereas the second group (20 patients) received a placebo. Both of them were administered on demand for 2 weeks. Dry Mouth Questionnaire (DMQ) was used in order to evaluate xerostomia levels before and after product/placebo application. Unstimulated and stimulated salivary flows rates, before and after application, were measured. All the statistical analyses were performed by using SPSS software v17.0. Different DMQ scores at the earliest and final stage of the trial were analysed by using Mann-Whitney U test, whereas Student’s T-test was used to analyse salivary flows. Critical p-value was established at p0.05) after placebo application. After two weeks of treatment with malic acid, unstimulated salivary flow increased from 0.17 to 0.242 mL/min whereas the stimulated one increased from 0.66 to 0.92 mL/min (p0.05). Conclusions: Malic acid 1% spray improved antihypertensive-induced xerostomia and stimulated the production of saliva. Key words:Xerostomia, hyposialia, malic acid, antihypertensive drugs. PMID:22926481

  19. Sialendoscopy for Patients with Radioiodine-Induced Sialadenitis and Xerostomia.

    Science.gov (United States)

    Bhayani, Mihir K; Acharya, Varun; Kongkiatkamon, Suchada; Farah, Sally; Roberts, Dianna B; Sterba, Jennifer; Chambers, Mark S; Lai, Stephen Y

    2015-07-01

    We examined outcomes in patients treated for radioactive iodine-induced sialadenitis (RAIS) and xerostomia with sialendoscopy. Data was prospectively collected for all patients undergoing sialendoscopy for RAIS from a single institution. Interventional details and intraoperative findings were recorded. Qualitative data were obtained through patient examination, telephone interviews, and use of a standard quality of life questionnaire, Xerostomia Questionnaire. Quantitative data were obtained from patients who underwent sialometry. Twenty-six patients (24 women and 2 men; median age, 43 years; age range, 19-57 years) underwent interventional sialendoscopy after conservative management of symptoms proved unsuccessful. Sialadenitis was present in 25 patients and xerostomia in 22 patients. Mucus plugging in the duct of the gland was the most common finding (22 patients) followed by stenosis (18 patients), inflammation (eight patients), and erythema (eight patients). Median follow-up time was 23.4±12.1 months. Sixteen patients (64%) reported complete resolution; seven (28%), partial resolution; one (4%), no change in symptoms; and one (4%), regression in RAIS-related symptoms. Patients subjectively noted the following regarding their xerostomia symptoms: seven (31.8%) had complete resolution; 10 (45.5%), partial resolution; four (18.2%), no change; and one (4.5%), regression. Statistical analysis of the available sialometry data revealed a statistically significant difference in saliva production at 6 months following sialendoscopy for unstimulated saliva production (p=0.028). Sialendoscopy is an effective treatment option for the management of RAIS and xerostomia refractory to conservative therapy and medical management. Patients in our cohort report durable improvement in symptoms after intervention.

  20. CT image biomarkers to improve patient-specific prediction of radiation-induced xerostomia and sticky saliva

    NARCIS (Netherlands)

    van Dijk, Lisanne V.; Brouwer, Charlotte L.; van der Schaaf, Arjen; Burgerhof, Johannes G. M.; Beukinga, Roelof J.; Langendijk, Johannes A.; Sijtsema, Nanna M.; Steenbakkers, Roel J. H. M.

    Background and purpose: Current models for the prediction of late patient-rated moderate-to-severe xerostomia (XER12m) and sticky saliva (STIC12m) after radiotherapy are based on dose-volume parameters and baseline xerostomia (XERbase) or sticky saliva (STICbase) scores. The purpose is to improve

  1. Efficacy and safety of pilocarpine for radiation-induced xerostomia in patients with head and neck cancer: A systematic review and meta-analysis.

    Science.gov (United States)

    Cheng, Cai-Qi; Xu, Hao; Liu, Ling; Wang, Rui-Nan; Liu, Yu-Ting; Li, Jing; Zhou, Xi-Kun

    2016-04-01

    Pilocarpine has been used widely in the treatment of dry mouth and glaucoma. In this review, the authors assessed the efficacy and safety of pilocarpine for patients with head and neck cancer who have radiation-induced xerostomia. The authors conducted a systematic search including meta-analyses and randomized controlled trials in the following databases: MEDLINE, Embase, Cochrane Library, and Science Citation Index Expanded. The primary outcome was the severity of xerostomia (measured using visual analog scale [VAS] scores). Adverse events were other outcomes of interest. The authors performed meta-analyses where appropriate. The authors used the Cochrane Collaboration's tool for assessing risk of bias to assess the quality of the study. The authors identified 6 studies (including 752 patients in total). The results of a meta-analysis of 3 articles showed that pilocarpine was associated with a 12-point increase in VAS score (mean difference, 12.00; 95% confidence interval [CI], 1.93-22.08; P = .02) and higher rates of adverse events compared with placebo in terms of sweating (odds ratio [OR], 3.71; 95% CI, 2.34-5.86; P xerostomia in patients with head and neck cancer. However, the authors of this systematic review found the best available evidence in the meta-analysis in 3 studies, 1 of which showed no effect. The authors of this systematic review suggest that these patients take 5 milligrams of pilocarpine 3 times daily, and that there is need for further study. Copyright © 2016 American Dental Association. Published by Elsevier Inc. All rights reserved.

  2. The efficacy of Xialine[reg] in patients with xerostomia resulting from radiotherapy for head and neck cancer: a pilot-study

    International Nuclear Information System (INIS)

    Jellema, Anke Petra; Langendijk, Hans; Bergenhenegouwen, Lester; Reijden, Willy van der; Leemans, Rene; Smeele, Ludy; Slotman, Berend J.

    2001-01-01

    Changes in subjective sensations due to xerostomia before and after administration of Xialine [reg] , a xanthan gum-based saliva substitute, were evaluated in 30 patients with radiation-induced xerostomia using the QLQ-H and N35. Xerostomia in general decreased with both Xialine [reg] and placebo to almost the same degree. A trend was seen for Xialine [reg] to improve problems with speech and senses

  3. Chemical Induced Xerostomia Among Institutionalized Eldery

    OpenAIRE

    Petrovski, Mihajlo; Minovska, Ana; Ivanovski, Kiro; Forna, Doriana Agop; Forna, Consuela Norna

    2015-01-01

    Subjective presence of dry mouth is most common oral problem among the institutionalized elderly. To assess the subjective presence of xerostomia among institutionalized elderly. Total numbers of 70 subjects older than 65 years institutionalized in one nursing home were evaluated. The subjective presence of xerstomia was determinated. To determine the level of expressiveness of xerostomia is used questionnaire recommended by Carda et al. 62.8% from the subjects believed that they ...

  4. A systematic review of salivary gland hypofunction and xerostomia induced by cancer therapies: management strategies and economic impact

    DEFF Research Database (Denmark)

    Jensen, S.B.; Pedersen, A.M.L.; Vissink, A.

    2010-01-01

    This systematic review aimed to assess the literature for management strategies and economic impact of salivary gland hypofunction and xerostomia induced by cancer therapies and to determine the quality of evidence-based management recommendations. The electronic databases of MEDLINE/PubMed and E......This systematic review aimed to assess the literature for management strategies and economic impact of salivary gland hypofunction and xerostomia induced by cancer therapies and to determine the quality of evidence-based management recommendations. The electronic databases of MEDLINE......, amifostine, muscarinic agonist stimulation, oral mucosal lubricants, acupuncture, and submandibular gland transfer. There is evidence that salivary gland hypofunction and xerostomia induced by cancer therapies can be prevented or symptoms be minimized to some degree, depending on the type of cancer treatment...... formulas, submandibular gland transfer, acupuncture, hyperbaric oxygen treatment, management strategies in pediatric cancer populations, and the economic consequences of salivary gland hypofunction and xerostomia...

  5. The QUANTEC criteria for parotid gland dose and their efficacy to prevent moderate to severe patient-rated xerostomia.

    Science.gov (United States)

    Beetz, Ivo; Steenbakkers, Roel J H M; Chouvalova, Olga; Leemans, Charles R; Doornaert, Patricia; van der Laan, Bernard F A M; Christianen, Miranda E M C; Vissink, Arjan; Bijl, Henk P; van Luijk, Peter; Langendijk, Johannes A

    2014-05-01

    Recently, the Quantitative Analysis of Normal Tissue Effect in the Clinic (QUANTEC) Group defined dose-volume constraints for the parotid glands to avoid severe xerostomia. The aim of this study was to determine if application of these QUANTEC criteria also protected against moderate-to-severe patient-rated xerostomia. The study population consisted of 307 head and neck cancer patients treated with primary (chemo)radiotherapy, either with 3D-CRT (56%) or with IMRT (44%). All patients participated in a standard follow-up program in which radiation-induced toxicity and quality of life were prospectively assessed. Patients who met the QUANTEC criteria were classified as low risk and otherwise as high risk. In total, 41% of the patients (treated with 3D-CRT and IMRT) were classified as low risk patients. In the group treated with 3D-CRT and IMRT, it was possible to meet the QUANTEC criteria in 47% and 32% of the patients, respectively. Sparing the parotid glands with IMRT was considerably more difficult in patients with lymph node metastases and in patients with nasopharyngeal and oropharyngeal tumours. Low risk patients reported significantly less moderate-to-severe xerostomia than high risk patients. However, the predicted risk of elderly patients and patients with pre-existing minor patient-rated xerostomia at baseline was > 20%, even when the QUANTEC criteria were met. Significantly lower rates of radiation-induced patient-rated xerostomia were found among low risk patients treated according to the QUANTEC criteria, but these criteria do not completely protect against xerostomia. Particularly in elderly patients and patients already suffering from minor xerostomia at baseline, the QUANTEC criteria do not sufficiently protect against persistent, moderate-to-severe patient-rated xerostomia.

  6. Xerostomia in patients treated for oropharyngeal carcinoma: comparing linear accelerator-based intensity-modulated radiation therapy with helical tomotherapy.

    Science.gov (United States)

    Fortin, Israël; Fortin, Bernard; Lambert, Louise; Clavel, Sébastien; Alizadeh, Moein; Filion, Edith J; Soulières, Denis; Bélair, Manon; Guertin, Louis; Nguyen-Tan, Phuc Felix

    2014-09-01

    In comparison to sliding-window intensity-modulated radiation therapy (sw-IMRT), we hypothesized that helical tomotherapy (HT) would achieve similar locoregional control and, at the same time, decrease the parotid gland dose, thus leading to a xerostomia reduction. The association between radiation techniques, mean parotid dose, and xerostomia incidence, was reviewed in 119 patients with advanced oropharyngeal carcinoma treated with concurrent chemoradiation using sw-IMRT (n = 59) or HT (n = 60). Ipsilateral and contralateral parotid mean doses were significantly lower for patients treated with HT versus sw-IMRT: 24 Gy versus 32 Gy ipsilaterally and 20 Gy versus 25 Gy contralaterally. The incidence of grade ≥2 xerostomia was significantly lower in the HT group than in the sw-IMRT group: 12% versus 78% at 6 months, 3% versus 51% at 12 months, and 0% versus 25% at 24 months. Total parotid mean dose xerostomia at 6, 12, and 24 months. This retrospective series suggests that using HT can better spare the parotid glands while respecting quantitative analysis of normal tissue effects in the clinic (QUANTEC)'s criteria. Copyright © 2013 Wiley Periodicals, Inc.

  7. CT image biomarkers to improve patient-specific prediction of radiation-induced xerostomia and sticky saliva.

    Science.gov (United States)

    van Dijk, Lisanne V; Brouwer, Charlotte L; van der Schaaf, Arjen; Burgerhof, Johannes G M; Beukinga, Roelof J; Langendijk, Johannes A; Sijtsema, Nanna M; Steenbakkers, Roel J H M

    2017-02-01

    Current models for the prediction of late patient-rated moderate-to-severe xerostomia (XER 12m ) and sticky saliva (STIC 12m ) after radiotherapy are based on dose-volume parameters and baseline xerostomia (XER base ) or sticky saliva (STIC base ) scores. The purpose is to improve prediction of XER 12m and STIC 12m with patient-specific characteristics, based on CT image biomarkers (IBMs). Planning CT-scans and patient-rated outcome measures were prospectively collected for 249 head and neck cancer patients treated with definitive radiotherapy with or without systemic treatment. The potential IBMs represent geometric, CT intensity and textural characteristics of the parotid and submandibular glands. Lasso regularisation was used to create multivariable logistic regression models, which were internally validated by bootstrapping. The prediction of XER 12m could be improved significantly by adding the IBM "Short Run Emphasis" (SRE), which quantifies heterogeneity of parotid tissue, to a model with mean contra-lateral parotid gland dose and XER base . For STIC 12m , the IBM maximum CT intensity of the submandibular gland was selected in addition to STIC base and mean dose to submandibular glands. Prediction of XER 12m and STIC 12m was improved by including IBMs representing heterogeneity and density of the salivary glands, respectively. These IBMs could guide additional research to the patient-specific response of healthy tissue to radiation dose. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  8. Xerostomia after Radiotherapy for Oral and Oropharyngeal Cancer

    DEFF Research Database (Denmark)

    Killerup Kaae, Julie; Stenfeldt, Lone; Eriksen, Jesper Grau

    2016-01-01

    INTRODUCTION: Radiation-induced xerostomia is a frequent late side effect after treatment for oral and oropharyngeal cancers. This may induce swallowing difficulties, compromised oral well-being, reduced nutrition intake, or speech deficiencies. Consequently, quality of life is often impaired...... oral well-being when used on a regular basis. METHODS: From October to December 2014, 31 consecutive patients treated with primary radiotherapy (RT) and concomitant cisplatin (in locally advanced cases) for oral or oropharyngeal cancer consented to participate. All patients had finalized RT 2-8 months...

  9. The Prevalence of Xerostomia Occurrence after Doing Radiation Therapy in Patients with Head and Neck Cancer

    Directory of Open Access Journals (Sweden)

    Barunawaty Yunus

    2017-04-01

    Full Text Available Xerostomia is one side effect of radiation therapy that most commonly affects head and neck. This situation is a symptom and not a disease which is generally associated with reduced saliva. For patients this situation is not pleasant and for dentist, this symptom is considered as a challenging case. This research intended to know the prevalence of xerostomia after radiation therapy in cancer patients with head and neck area. The subjects of this study were patients with head and neck area cancer who underwent radiotherapy treatment at Hasanuddin University teaching hospital, subjects were then taken saliva before and after given a total dose of 20 Gy and a total dose of 40 Gy. The analysis of the data processed by the computer program and the Wilcoxon test significance level is accepted when p<0.05. The mean bulk saliva before radiotherapy was higher than average rainfall saliva after radiotherapy total dose of 20 Gy and 40 Gy. Radiotherapy of the head and neck area total dose of 20 Gy and 40 Gy may affect rainfall saliva so that patients feel the symptoms of xerostomia.

  10. Xerostomia: A review

    Directory of Open Access Journals (Sweden)

    V Vivek

    2007-01-01

    Full Text Available Saliva plays a key role in the maintenance of oral health. Xerostomia or reduced salivary flow is a common clinical complaint that predisposes individuals to oral diseases and considerable discomfort that may manifest as increased incidence of caries, susceptibility to oral Candidiasis, altered taste sensation, glossodynia and numerous other problems. Xerostomia may occur with the use of medication; as a complication of connective tissue and autoimmune diseases; with radiation to the head and neck region; or with a number of other systemic or local conditions. Investigations for xerostomia include a thorough clinical and oral examination; salivary flow rate estimation; radiologic and histopathologic examination of the salivary glands. Clinical laboratory tests are also indicated to help in the diagnosis. Patient education plays a vital role in the management of Xerostomia. The general approach to treatment consists of palliative treatment for the relief of symptoms and prevention of oral complications. Relief of symptoms may be achieved by paying rigorous attention to personal oral hygiene; diet counseling; drug substitution/dose modification. Salivary flow may be enhanced by using medication or by gustatory stimulation. Artificial saliva substitutes may be used for relieving symptoms. Alternative therapy like acupuncture may be sought if conventional treatment has failed to offer relief. Complications like increased incidence of dental caries, candidiasis, difficulty in using dentures, usually associated with Xerostomia can be managed by giving rigorous attention to personal and professional oral hygiene measures; strict adherence to non cariogenic diet; placement of sealants and topical fluorides; and anti-fungal therapy.

  11. Interventions for the management of radiotherapy-induced xerostomia and hyposalivation: A systematic review and meta-analysis.

    Science.gov (United States)

    Mercadante, Valeria; Al Hamad, Arwa; Lodi, Giovanni; Porter, Stephen; Fedele, Stefano

    2017-03-01

    Salivary gland hypofunction is a common and permanent adverse effect of radiotherapy to the head and neck. Randomised trials of available treatment modalities have produced unclear results and offer little reliable guidance for clinicians to inform evidence-based therapy. We have undertaken this systematic review and meta-analysis to estimate the effectiveness of available interventions for radiotherapy-induced xerostomia and hyposalivation. We searched MEDLINE, Cochrane Central, EMBASE, AMED, and CINAHL database through July 2016 for randomised controlled trials comparing any topical or systemic intervention to active and/or non-active controls for the treatment of radiotherapy-induced xerostomia. The results of clinically and statistically homogenous studies were pooled and meta-analyzed. 1732 patients from twenty studies were included in the systematic review. Interventions included systemic or topical pilocarpine, systemic cevimeline, saliva substitutes/mouthcare systems, hyperthermic humidification, acupuncture, acupuncture-like transcutaneous electrical nerve stimulation, low-level laser therapy and herbal medicine. Results from the meta-analysis, which included six studies, suggest that both cevimeline and pilocarpine can reduce xerostomia symptoms and increase salivary flow compared to placebo, although some aspects of the relevant effect size, duration of the benefit, and clinical meaningfulness remain unclear. With regard to interventions not included in the meta-analysis, we found no evidence, or very weak evidence, that they can reduce xerostomia symptoms or increase salivary flow in this population. Pilocarpine and cevimeline should represent the first line of therapy in head and neck cancer survivors with radiotherapy-induced xerostomia and hyposalivation. The use of other treatment modalities cannot be supported on the basis of current evidence. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Stem cells and the repair of radiation-induced salivary gland damage

    NARCIS (Netherlands)

    Coppes, R. P.; Stokman, M. A.

    Hyposalivation underlying xerostomia after radiotherapy is still a major problem in the treatment of head and neck cancer. Stem cell therapy may provide a means to reduce radiation-induced hyposalivation and improve the quality of life of patients. This review discusses the current status in

  13. Xerostomia and medication: a cross-sectional study in long-term geriatric wards.

    Science.gov (United States)

    Desoutter, A; Soudain-Pineau, M; Munsch, F; Mauprivez, C; Dufour, T; Coeuriot, J-L

    2012-01-01

    The purpose of this study was to determine the prevalence of xerostomia in old people living in long-term geriatric wards, and to measure the relationship between xerostomia and etiologic factors such as age and medication (total number of medications, xerogenic medications, anticholinergic medications and medications that induce hypersialorrhea). An observational retrospective, comparative, multicentre epidemiological study. Long-term geriatric wards, in Reims, France. 769 old people living in long-term geriatric wards. Prevalence of xerostomia assessed from age, total number of medications, xerogenic medications, anticholinergic medications and those that induce hypersialorrhea. Multivariable logistic regression was used to calculate Odds Ratios (OR) and their 95% Confidence Intervals (95% CI). Among 769 old people (average age 84.6±8.4 years old), 287 residents suffered from xerostomia (37.3%). Significant predictors of xerostomia were: resident's age OR=1.56, 95% CI (1.30-1.88), pxerostomia identified was medications that induce hypersialorrhea OR=0.81, 95% CI (0.67-0.98), p=0.03. The total number of medications and xerogenic medications did not play a significant role in xerostomia. Increasing Age and anticholinergic medications induce a dry mouth. Conversely, the total number of medications and xerogenic medications do not influence xerostomia. Medications that induce hypersialorrhea protect against the occurrence of dry mouth.

  14. Xerostomia in the Geriatric Patient: Causes, Oral Manifestations, and Treatment.

    Science.gov (United States)

    Ouanounou, Aviv

    2016-05-01

    Xerostomia, or dry mouth, is common among elderly people and is typically associated with decreased salivary gland function. Causes of xerostomia in the geriatric population have been attributed to the use of medications, chronic disorders, and radiation therapy to the head and neck region. Patients with chronic xerostomia may have multiple oral and dental consequences such as dental caries, periodontal disease, fungal infections, ill-fitting dentures, and taste alterations. Xerostomia can seriously impact quality of life and may alter speech, eating, and swallowing. Current therapeutics for the management of xerostomia are grouped as local and systemic salivary stimulation. This article reviews the main reasons for xerostomia and the complications it causes in the oral cavity. It also discusses the pharmacologic and nonpharmacologic agents used to treat this condition.

  15. Silicon radiation detector analysis using back electron beam induced current

    International Nuclear Information System (INIS)

    Guye, R.

    1987-01-01

    A new technique for the observation and analysis of defects in silicon radiation detectors is described. This method uses an electron beam from a scanning electron microscope (SEM) impinging on the rear side of the p + n junction of the silicon detector, which itself is active and detects the electron beam induced current (EBIC). It is shown that this current is a sensitive probe of localized trapping centers, either at the junction surface or somewhere in the volume of the silicon crystal. (orig.)

  16. Electron Beam Induced Radiation Damage of the Semiconductor Radiation Detector based on Silicon

    International Nuclear Information System (INIS)

    Kim, Han Soo; Kim, Yong Kyun; Park, Se Hwan; Haa, Jang Ho; Kang, Sang Mook; Chung, Chong Eun; Cho, Seung Yeon; Park, Ji Hyun; Yoon, Tae Hyung

    2005-01-01

    A Silicon Surface Barrier (SSB) semiconductor detector which is generally used to detect a charged particle such as an alpha particle was developed. The performance of the developed SSB semiconductor detector was measured with an I-V curve and an alpha spectrum. The response for an alpha particle was measured by Pu-238 sources. A SSB semiconductor detector was irradiated firstly at 30sec, at 30μA and secondly 40sec, 40μA with a 2MeV pulsed electron beam generator in KAERI. And the electron beam induced radiation damage of a homemade SSB detector and the commercially available PIN photodiode were investigated. An annealing effect of the damaged SSB and PIN diode detector were also investigated using a Rapid Thermal Annealing (RTA). This data may assist in designing the silicon based semiconductor radiation detector when it is operated in a high radiation field such as space or a nuclear power plant

  17. Mesenchymal stem cell therapy for salivary gland dysfunction and xerostomia: a systematic review of preclinical studies

    DEFF Research Database (Denmark)

    Jensen, David Hebbelstrup; Oliveri, Roberto Stefan; Trojahn-Kølle, Stig-Frederik

    2014-01-01

    was to assess, through systematic review, the potential benefit of mesenchymal stem cell (MSC) therapy in radiation-induced and SS-related salivary gland dysfunction and xerostomia. We searched PubMed/MEDLINE, Embase, Web of Science, the Cochrane Database of Systematic Reviews, the World Health Organization......The most severe forms of xerostomia and salivary gland dysfunction, as well as a severely reduced quality of life, are seen in Sjögren syndrome (SS) and after radiotherapy for head and neck cancer. For both conditions, no effective regenerative therapies yet exist. Thus, the aim of this article...

  18. Oral pilocarpine for radiation-induced xerostomia: integrated efficacy and safety results from two prospective randomized clinical trials

    International Nuclear Information System (INIS)

    Rieke, John W.; Hafermann, Mark D.; Johnson, Jonas T.; LeVeque, Francis G.; Iwamoto, Ryan; Steiger, Barry W.; Muscoplat, Charles; Gallagher, Susan C.

    1995-01-01

    Purpose: Pilocarpine hydrochloride administered in either a fixed-dose or in a dose-titration protocol three times a day for 12 weeks was evaluated for its ability to relieve symptoms of postradiation xerostomia and to improve saliva production. The studies were randomized, double-blind, placebo-controlled, multicenter clinical trials. A total of 369 patients who had received at least 40 Gy of radiation to the head and neck with clinically significant xerostomia were enrolled in the two studies. In the dose-titration study, 162 patients were enrolled and they received a thrice daily regimen of 2.5 mg tablets for first 4 weeks, 5.0 mg tablets for the second 4 weeks, and 10.0 mg tablets for last 4 weeks of a 12-week study. Patients in the titration study were allowed to down titrate following at least one dose escalation to alleviate bothersome side effects, if any. In the fixed dose study, 207 patients received either placebo, 5.0 mg, or 10.0 mg tablets t.i.d. for 12 weeks. Methods and Materials: Patients were evaluated for symptomatic relief by responding to questionnaires using visual analog scales and categorical questions; and, for saliva production by sialometry. Questionnaires measured relief of intraoral dryness, improvement in overall condition (global response), oral discomfort, difficulty in speaking, chewing and swallowing, denture wearing, and usage of artificial saliva. Evaluations were conducted at baseline, and weeks 4, 8, and 12. Results: There were statistically significant improvements in salivary flow in pilocarpine treatment groups vs. placebo. There was a significant improvement in the overall 'global' condition of xerostomia associated with the use of pilocarpine in both studies. In the fixed-dose study, there were significant improvements in oral dryness, mouth comfort, ability to speak, and reduction in the use of oral comfort agents. The dose-titration study showed improvements in dryness that approached significance (p = 0.057) and a

  19. Geometric Image Biomarker Changes of the Parotid Gland Are Associated With Late Xerostomia.

    Science.gov (United States)

    van Dijk, Lisanne V; Brouwer, Charlotte L; van der Laan, Hans Paul; Burgerhof, Johannes G M; Langendijk, Johannes A; Steenbakkers, Roel J H M; Sijtsema, Nanna M

    2017-12-01

    To identify a surrogate marker for late xerostomia 12 months after radiation therapy (Xer 12m ), according to information obtained shortly after treatment. Differences in parotid gland (PG) were quantified in image biomarkers (ΔIBMs) before and 6 weeks after radiation therapy in 107 patients. By performing stepwise forward selection, ΔIBMs that were associated with Xer 12m were selected. Subsequently other variables, such as PG dose and acute xerostomia scores, were added to improve the prediction performance. All models were internally validated. Prediction of Xer 12m based on PG surface reduction (ΔPG-surface) was good (area under the receiver operating characteristic curve, 0.82). Parotid gland dose was related to ΔPG-surface (Pxerostomia scores to the ΔPG-surface improved the prediction of Xer 12m significantly, and vice versa. The final model including ΔPG-surface and acute xerostomia had outstanding performance in predicting Xer 12m early after radiation therapy (area under the receiver operating characteristic curve, 0.90). Parotid gland surface reduction was associated with late xerostomia. The early posttreatment model with ΔPG-surface and acute xerostomia scores can be considered as a surrogate marker for late xerostomia. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  20. Submandibular gland-sparing radiation therapy for locally advanced oropharyngeal squamous cell carcinoma: patterns of failure and xerostomia outcomes

    International Nuclear Information System (INIS)

    Gensheimer, Michael F; Liao, Jay J; Garden, Adam S; Laramore, George E; Parvathaneni, Upendra

    2014-01-01

    Saliva from submandibular glands (SMG) is necessary to minimize xerostomia. It is unclear whether SMG can be safely spared in patients undergoing bilateral neck radiotherapy for locally advanced oropharyngeal cancer without increasing the risk of marginal recurrence. We evaluated the outcomes of contralateral submandibular gland (cSMG) sparing intensity-modulated radiation therapy (IMRT). All patients with stage III/IV oropharyngeal squamous cell carcinoma treated with bilateral neck IMRT from 2006–2012 at our institution were included. Appropriately selected patients with favorable primary tumor characteristics and no definite contralateral neck disease were treated with cSMG-sparing IMRT. Patterns of failure and xerostomia outcomes were retrospectively analyzed. 114 patients were treated. 89% had stage IV disease and 89% received definitive radiation therapy. 76 patients (67%) received cSMG sparing IMRT. With a median follow-up of 30 months, there were 10 local, 9 regional, and 10 distant recurrences. 2-year overall survival was 86% and 2-year loco-regional control was 87%. In cSMG spared patients, the mean cSMG dose was 30.7 Gy. Late grade 2+ xerostomia was significantly reduced in the cSMG spared group compared to those without SMG sparing (6 months: 23% vs. 72%, 12 months: 6% vs. 41%, 24 months: 3% vs. 36%, all p < 0.0007). There were no peri-SMG marginal recurrences in the cSMG-spared cohort. cSMG sparing IMRT did not increase marginal failures in this series of locally advanced oropharyngeal SCC patients. Xerostomia was significantly reduced in cSMG spared patients

  1. Analysis of Factors Influencing the Development of Xerostomia during Intensity-Modulated Radiotherapy

    Science.gov (United States)

    Randall, Ken; Stevens, Jason; Yepes, Juan Fernando; Randall, Marcus E.; Kudrimoti, Mahesh; Feddock, Jonathan; Xi, Jing; Kryscio, Richard J.; Miller, Craig S.

    2013-01-01

    OBJECTIVES Factors influencing xerostomia during intensity-modulated radiation therapy (IMRT) were assessed. METHODS A 6-week study of 32 head and neck cancer (HNC) patients was performed. Subjects completed the Xerostomia Inventory (XI) and provided stimulated saliva (SS) at baseline, week two and at end of IMRT. Influence of SS flow rate (SSFR), calcium and mucin 5b (MUC5b) concentrations and radiation dose on xerostomia was determined. RESULTS HNC subjects experienced mean SSFR decline of 36% by visit two (N=27; p=0.012) and 57% by visit three (N=20; p=0.0004), Concentrations of calcium and MUC5b increased, but not significantly during IMRT (p>0.05). Xerostomia correlated most with decreasing salivary flow rate as determined by Spearman correlations (pxerostomia. PMID:23523462

  2. Evaluation of xerostomia following 3 dimensional conformal radiotherapy for nasopharyngeal cancer patients

    International Nuclear Information System (INIS)

    Park, Young Je; Ahn, Yong Chan; Park, Won; Ju, Sang Gyu; Nam, Hee Rim; Oh, Dong Ryul; Park, Hee Chul

    2006-01-01

    This study is to evaluate the xerostomia following 3-dimensional conformal radiation therapy (3D CRT) in nasopharynx cancer patients using the xerostomia questionnaire score (XQS). Questionnaire study was done on 51 patients with nasopharynx cancer who received 3D CRT from Dec. 2000 to Aug. 2005. 3D CRT technique is based on 'serial shrinking field' concept by 3 times of computed tomography (CT) simulation. Total target dose to the primary tumor was 72 Gy with 1.8 Gy daily fractions. Xerostomia was assessed with 4-questions XQS, and the associations between XQS and time elapsed after RT, age, sex, stage, concurrent chemotherapy, an parotid dose were analyzed. Concurrent chemotherapy was given to 40 patients and RT alone was given to 11 patients. The median time elapsed after 3D CRT was 20 (1 ∼ 58) months and the mean XQS of all 51 patients was 8.4 ± 1.9 (6 ∼ 14). XQS continuously and significantly decreased over time after 3D CRT (χ 2 -0.484, ρ < 0.05). There was no significant difference in XQS according to sex, age, and stag. However, XQS of concurrent chemotherapy patients was significantly higher than RT alone patients (ρ = 0.001). XQS of patients receiving total mean parotid dose ≥ 35 Gy was significantly higher than < 35 Gy (ρ = 0.05). Decreasing tendency of XQS over time after 3D CRT was observed. Concurrent chemotherapy and total mean parotid dose ≥ 35 Gy were suggested to adversely affect radiation-induced xerostomia

  3. Metabolic Imaging Biomarkers of Postradiotherapy Xerostomia

    Energy Technology Data Exchange (ETDEWEB)

    Cannon, Blake [Department of Radiation Physics, University of Texas M. D. Anderson Cancer Center, Houston, Texas (United States); Schwartz, David L., E-mail: dschwartz3@nshs.edu [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, Texas (United States); Department of Radiation Medicine, Hofstra North Shore-LIJ School of Medicine, New Hyde Park, New York (United States); Feinstein Institute for Medical Research, Manhasset, New York (United States); Dong Lei [Department of Radiation Physics, University of Texas M. D. Anderson Cancer Center, Houston, Texas (United States)

    2012-08-01

    Purpose: Xerostomia is a major complication of head and neck radiotherapy (RT). Available xerostomia measures remain flawed. [{sup 18}F]fluorodeoxyglucose-labeled positron emission tomography-computed tomography (FDG-PET-CT) is routinely used for staging and response assessment of head and neck cancer. We investigated quantitative measurement of parotid gland FDG uptake as a potential biomarker for post-RT xerostomia. Methods and Materials: Ninety-eight locally advanced head and neck cancer patients receiving definitive RT underwent baseline and post-RT FDG-PET-CT on a prospective imaging trial. A separate validation cohort of 14 patients underwent identical imaging while prospectively enrolled in a second trial collecting sialometry and patient-reported outcomes. Radiation dose and pre- and post-RT standard uptake values (SUVs) for all voxels contained within parotid gland ROI were deformably registered. Results: Average whole-gland or voxel-by-voxel models incorporating parotid D{sub Met} (defined as the pretreatment parotid SUV weighted by dose) accurately predicted posttreatment changes in parotid FDG uptake (e.g., fractional parotid SUV). Fractional loss of parotid FDG uptake closely paralleled early parotid toxicity defined by posttreatment salivary output (p < 0.01) and Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer xerostomia scores (p < 0.01). Conclusions: In this pilot series, loss of parotid FDG uptake was strongly associated with acute clinical post-RT parotid toxicity. D{sub Met} may potentially be used to guide function-sparing treatment planning. Prospective validation of FDG-PET-CT as a convenient, quantifiable imaging biomarker of parotid function is warranted and ongoing.

  4. Pathogenesis of salivary gland disease and xerostomia. The conception of Mikulicz's disease based on new knowledge

    International Nuclear Information System (INIS)

    Himi, Tetsuo; Kanaizumi, Etsuko; Ogasawara, Noriko; Yamamoto, Motohisa; Takahashi, Hiroki

    2007-01-01

    This review focuses on two topics of salivary gland diseases regarding xerostomia. First, the pathogenesis and treatment of xerostomia after radiotherapy against head and neck cancer is discussed. It is well known that the extent of radiation-induced salivary dysfunction and mucositis depends on the radiation dose and field. Moreover, the balance in the defense system of oropharyngeal cavity alters after radiotherapy. This altered balance may impair the ability to maintain the stable immunological control mechanism. Second, the newly established concept about Mikulicz's disease is discussed. Recently, elevated IgG4 concentration in serum and prominent infiltrating by plasmacytes expressing IgG4 in the salivary glands in Mikulicz's disease were revealed. Mikulicz's disease is different from Sjoegren's syndrome, and may be a systemic IgG4-related plasmacytic disease. (author)

  5. Emission of electromagnetic radiation from beam driven plasmas

    International Nuclear Information System (INIS)

    Newman, D.L.

    1985-01-01

    Two production mechanisms for electromagnetic radiation from a plasma containing electron-beam-driven weak Langmuir turbulence are studied: induced Compton conversion and two-Langmuir-wave coalescence. Induced Compton conversion in which a Langmuir wave scatters off a relativistic electron while converting into a transversely polarized electromagnetic wave is considered as a means for producing amplified electromagnetic radiation from a beam-plasma system at frequencies well above the electron plasma frequency. The induced emission growth rates of the radiation produced by a monoenergetic ultrarelativistic electron beam are determined as a function of the Langmuir turbulence spectrum in the background plasma and are numerically evaluated for a range of model Langmuir spectra. Induced Compton conversion can play a role in emission from astrophysical beam-plasma systems if the electron beam is highly relativistic and sufficiently narrow. However, it is found that the growth rates for this process are too small in all cases studied to account for the intense high-frequency radiation observed in laboratory experiments. Two-Langmuir-wave coalescence as a means of producing radiation at 2omega/sub p/ is investigated in the setting of the earth's foreshock

  6. Chronic xerostomia increases esophageal acid exposure and is associated with esophageal injury

    Energy Technology Data Exchange (ETDEWEB)

    Korsten, M.A.; Rosman, A.S.; Fishbein, S.; Shlein, R.D.; Goldberg, H.E.; Biener, A. (Gastrointestinal Section, Veterans Affairs Medical Center, Bronx, New York (USA))

    1991-06-01

    OBJECTIVES: To assess the effects of chronic xerostomia on parameters of gastroesophageal reflux and esophagitis. DESIGN: Observational study of a cohort of male patients with xerostomia and age-matched control subjects. SETTING: Tertiary-care Veterans Affairs Medical Center. SUBJECTS: Sixteen male patients with chronic xerostomia secondary to radiation for head and neck cancers or medications. Nineteen age-matched male control subjects with comparable alcohol and smoking histories. MEASUREMENTS AND MAIN RESULTS: Esophageal motility was similar in patients with xerostomia and controls. Clearance of acid from the esophagus and 24-hour intraesophageal pH were markedly abnormal in patients with xerostomia. Symptoms and signs of esophagitis were significantly more frequent in subjects with xerostomia. CONCLUSIONS: Chronic xerostomia may predispose to esophageal injury, at least in part, by decreasing the clearance of acid from the esophagus and altering 24-hour intraesophageal pH. Esophageal injury is a previously unreported complication of long-term salivary deficiency.

  7. Chronic xerostomia increases esophageal acid exposure and is associated with esophageal injury

    International Nuclear Information System (INIS)

    Korsten, M.A.; Rosman, A.S.; Fishbein, S.; Shlein, R.D.; Goldberg, H.E.; Biener, A.

    1991-01-01

    OBJECTIVES: To assess the effects of chronic xerostomia on parameters of gastroesophageal reflux and esophagitis. DESIGN: Observational study of a cohort of male patients with xerostomia and age-matched control subjects. SETTING: Tertiary-care Veterans Affairs Medical Center. SUBJECTS: Sixteen male patients with chronic xerostomia secondary to radiation for head and neck cancers or medications. Nineteen age-matched male control subjects with comparable alcohol and smoking histories. MEASUREMENTS AND MAIN RESULTS: Esophageal motility was similar in patients with xerostomia and controls. Clearance of acid from the esophagus and 24-hour intraesophageal pH were markedly abnormal in patients with xerostomia. Symptoms and signs of esophagitis were significantly more frequent in subjects with xerostomia. CONCLUSIONS: Chronic xerostomia may predispose to esophageal injury, at least in part, by decreasing the clearance of acid from the esophagus and altering 24-hour intraesophageal pH. Esophageal injury is a previously unreported complication of long-term salivary deficiency

  8. Hyposalivation and xerostomia in dentate older adults

    Science.gov (United States)

    Wiener, R. Constance; Wu, Bei; Crout, Richard; Wiener, Michael; Plassman, Brenda; Kao, Elizabeth; McNeil, Daniel

    2010-01-01

    Background Older adults are susceptible to reduced saliva production related to certain medications, radiation and chronic conditions. Many of these people have many physical and oral health problems and limited access to dental care. The use of effective screening tools for xerostomia and hyposalivation would be helpful in identifying those at risk. The authors conducted a study to investigate the association between three measures of oral dryness: hyposalivation (low unstimulated salivary flow), self-reported xerostomia and clinically assessed dry mouth. Methods The authors included a convenience sample of 252 nondemented and dentate West Virginia participants 70 years and older who were part of a larger study on oral health and cognition among older adults. Participants completed a self-reported xerostomia index, provided an unstimulated salivary sample and underwent an oral assessment for the study. Results Twenty-eight (11.1 percent) had hyposalivation, eight of whom reported having xerostomia (sensitivity = 28.6 percent). Of the 43 participants who reported having xerostomia, only eight had hyposalivation (positive predictive value = 18.6 percent). Hyposalivation and self-reported xerostomia were not significantly related. Clinically assessed dry mouth correlated modestly, but significantly, with hyposalivation and self-reported xerostomia. Conclusions Obtaining routine unstimulated salivary flow rates in addition to self-reported information and oral evaluations may increase early detection of oral dryness, which would assist in implementing early interventions to improve patients’ quality of life. Clinical Implications Visually inspecting oral tissues for dryness and asking a patient if his or her mouth is dry are insufficient measures for clinicians to use to determine if the patient has hyposalivation. The authors recommend that clinicians determine the patients’ unstimulated salivary flow rate. PMID:20194383

  9. Mastication and swallowing in patients with postirradiation xerostomia

    International Nuclear Information System (INIS)

    Hamlet, Sandra; Faull, Jennifer; Klein, Barbara; Aref, Amr; Fontanesi, James; Stachler, Robert; Shamsa, Falah; Jones, Lewis; Simpson, Mark

    1997-01-01

    Purpose: Very little objective data has been reported on mastication and swallowing in xerostomic patients, which would substantiate presumed causal relationships between xerostomia and patient complaints. The purpose was to elucidate which components of mastication and swallowing were abnormal, and most directly related to xerostomia, and which appeared unaffected. Methods and Materials: A retrospective analysis of timing events in mastication and swallowing was done using videofluoroscopic data for 15 cancer patients with xerostomia, and 20 normal controls. Scintigraphy was also used to determine oropharyngeal residue after a water swallow. Cancer treatment modalities included radiation therapy or chemoradiation therapy. Results: For barium liquid and paste substances, timing measures were equivalent for controls and patients. Xerostomic patients took 46% longer to masticate a shortbread cookie, and timing for the initiation of swallowing was shorter, but duration of swallowing appeared unaffected. Oral and pharyngeal residues following the swallow were greater in the patient group. Conclusions: Xerostomia primarily affected mastication and oral manipulation of a dry, absorbent food material. Increased oral and pharyngeal residues after a water swallow are ambiguously related to xerostomia. The initiation and duration of the pharyngeal swallow was not abnormal

  10. Reduction of xerostomia in head and neck cancer patients. A critical review of the literature

    International Nuclear Information System (INIS)

    Hanley, O.; Leech, M.

    2016-01-01

    Background: Radical radiotherapy given with or without concurrent chemotherapy is the main treatment modality in non-surgical patients for the management of squamous cell carcinoma in the head and neck. Xerostomia, which results from reduced salivary production is a debilitating side-effect of radiation therapy to these patients. Xerostomia may greatly impact on quality of life for head and neck cancer patients for up to 24 months post-radiation therapy. Such effects include difficulties in fundamental daily activities such as speech, mastication and swallowing. It is believed that modulated techniques provide better sparing to surrounding salivary glands. The aim of this critical review of the literature is to investigate what advantage intensity modulated radiotherapy (IMRT) can provide over 3 dimensional conformal radiation therapy (3DCRT) in reducing xerostomia in this subset of patients. Search methodology: An extensive literature search was undertaken to compare the incidence of grade 2 or worse xerostomia in HNSCC patients treated with IMRT or 3DCRT (±chemotherapy). Results: Studies reported a lower incidence of grade 2 or worse xerostomia with IMRT over patients treated with 3DCRT. The highest incidence of xerostomia was reported at 6 months following the completion of radiotherapy treatment. The incidence of xerostomia in patients declined with time, in both patients treated with IMRT and those of the 3DCRT cohort. The incidence of xerostomia was greater in the acute setting than in the late. Conclusion: An IMRT technique can consistently reduce grade 2 or worse xerostomia in head and neck cancer patients over conformal techniques. This will not compromise dose homogeneity or dose coverage. IMRT should remain the standard of care for head and neck patients. - Highlights: • IMRT technique can consistently reduce grade 2 or worse xerostomia in head and neck cancer patients over 3DCRT. • IMRT does not compromise the treatment's dose homogeneity or

  11. Ion beam induced charge and cathodoluminescence imaging of response uniformity of CVD diamond radiation detectors

    CERN Document Server

    Sellin, P J; Galbiati, A; Maghrabi, M; Townsend, P D

    2002-01-01

    The uniformity of response of CVD diamond radiation detectors produced from high quality diamond film, with crystallite dimensions of >100 mu m, has been studied using ion beam induced charge imaging. A micron-resolution scanning alpha particle beam was used to produce maps of pulse height response across the device. The detectors were fabricated with a single-sided coplanar electrode geometry to maximise their sensitivity to the surface region of the diamond film where the diamond crystallites are highly ordered. High resolution ion beam induced charge images of single crystallites were acquired that demonstrate variations in intra-crystallite charge transport and the termination of charge transport at the crystallite boundaries. Cathodoluminescence imaging of the same crystallites shows an inverse correlation between the density of radiative centres and regions of good charge transport.

  12. IMRT for head and neck cancer: reducing xerostomia and dysphagia

    International Nuclear Information System (INIS)

    Wang, XiaoShen; Eisbruch, Avraham

    2016-01-01

    Dysphagia and xerostomia are the main sequellae of chemoradiotherapy for head and neck cancer, and the main factors in reducing long-term patient quality of life. IMRT uses advanced technology to focus the high radiation doses on the targets and avoid irradiation of non-involved tissues. The decisions about sparing organs and tissues whose damage causes xerostomia and dysphagia depends on the evidence for dose–response relationships for the organs causing these sequellae. This paper discusses the evidence for the contribution of radiotherapy to xerostomia via damage of the major salivary glands (parotid and submandibular) and minor salivary glands within the oral cavity, and the contribution of radiotherapy-related effect on important swallowing structures causing dysphagia. Recommendations for dose limits to these organs, based on measurements of xerostomia and dysphagia following radiotherapy, are provided here

  13. Weak-beam electron microscopy of radiation-induced segregation

    International Nuclear Information System (INIS)

    Saka, H.

    1983-01-01

    The segregation of solute atoms to dislocations during irradiation by 1 MeV electrons in a HVEM was studied by measuring the dissociation width of extended dislocations in Cu-5.1 at.%Si, Cu-5.3 at.%Ge, Ag-9.4 at.% In and Ag-9.6 at.%Al alloys. 'Weak-beam' electron microscopy was used. In Cu-Si (oversized solute), Cu-Ge (oversize) and Ag-Al (undersize), solute enrichment was observed near dislocations, while in Ag-In (oversize) solute depletion was observed. The results are discussed in terms of current mechanisms for radiation-induced segregation. (author)

  14. Ion beam induced luminescence: Relevance to radiation induced bystander effects

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, S.B., E-mail: ahmad.rabilal@gmail.com [Medical Physics and Applied Radiation Sciences, University of McMaster, Hamilton, Ontario (Canada); McNeill, F.E., E-mail: fmcneill@mcmaster.ca [Medical Physics and Applied Radiation Sciences, University of McMaster, Hamilton, Ontario (Canada); Byun, S.H., E-mail: soohyun@mcmaster.ca [Medical Physics and Applied Radiation Sciences, University of McMaster, Hamilton, Ontario (Canada); Prestwich, W.V., E-mail: prestwic@mcmaster.ca [Medical Physics and Applied Radiation Sciences, University of McMaster, Hamilton, Ontario (Canada); Seymour, C., E-mail: seymouc@mcmaster.ca [Medical Physics and Applied Radiation Sciences, University of McMaster, Hamilton, Ontario (Canada); Mothersill, C.E., E-mail: mothers@mcmaster.ca [Medical Physics and Applied Radiation Sciences, University of McMaster, Hamilton, Ontario (Canada)

    2012-10-01

    The aim of this work is quantify the light emitted as a result of charged particle interaction in materials which may be of relevance to radiation induced 'bystander effects' studies. We have developed a system which employs single photon counting to measure the light emitted from samples irradiated under vacuum by a charged particle beam. The system uses a fast photomultiplier tube with a peak cathode response at 420 nm. It has been tested in a proof-of-principle experiment using polystyrene targets. Light output, as a result of irradiation, was measured. The luminescence yield appears to have a non-linear behavior with the incident ion fluence: it rises exponentially to an asymptotic value. The target was irradiated with beam energies varying from 1 to 2 MeV and showed saturation at or before an incident fluence rate of 3 Multiplication-Sign 10{sup 13} H{sup +}/cm{sup 2} s. The average saturation value for the photon output was found to be 40 Multiplication-Sign 10{sup 6} cps. Some measurements were performed using filters to study the emission at specific wavelengths. In the case of filtered light measurements, the photon output was found to saturate at 28 Multiplication-Sign 10{sup 3}, 10 Multiplication-Sign 10{sup 6}, and 35 Multiplication-Sign 10{sup 6} cps for wavelengths of 280 {+-} 5 nm, 320 {+-} 5 nm and 340 {+-} 5 nm respectively. The light output reaches a maximum value because of damage induced in the polymer. Our measurements indicate a 'damage cross section' of the order of 10{sup -14} cm{sup 2}. The average radiant intensity was found to increase at wavelengths of 280 and 320 nm when the proton energy was increased. This was not found to occur at 340 nm. In conclusion, the light emission at specific wavelengths was found to depend upon the incident proton fluence and the proton energy. The wavelengths of the emitted light measured in this study have significance for the understanding of radiation induced bystander effects.

  15. Ion beam induced luminescence: Relevance to radiation induced bystander effects

    Science.gov (United States)

    Ahmad, S. B.; McNeill, F. E.; Byun, S. H.; Prestwich, W. V.; Seymour, C.; Mothersill, C. E.

    2012-10-01

    The aim of this work is quantify the light emitted as a result of charged particle interaction in materials which may be of relevance to radiation induced "bystander effects" studies. We have developed a system which employs single photon counting to measure the light emitted from samples irradiated under vacuum by a charged particle beam. The system uses a fast photomultiplier tube with a peak cathode response at 420 nm. It has been tested in a proof-of-principle experiment using polystyrene targets. Light output, as a result of irradiation, was measured. The luminescence yield appears to have a non-linear behavior with the incident ion fluence: it rises exponentially to an asymptotic value. The target was irradiated with beam energies varying from 1 to 2 MeV and showed saturation at or before an incident fluence rate of 3 × 1013 H+/cm2 s. The average saturation value for the photon output was found to be 40 × 106 cps. Some measurements were performed using filters to study the emission at specific wavelengths. In the case of filtered light measurements, the photon output was found to saturate at 28 × 103, 10 × 106, and 35 × 106 cps for wavelengths of 280 ± 5 nm, 320 ± 5 nm and 340 ± 5 nm respectively. The light output reaches a maximum value because of damage induced in the polymer. Our measurements indicate a "damage cross section" of the order of 10-14 cm2. The average radiant intensity was found to increase at wavelengths of 280 and 320 nm when the proton energy was increased. This was not found to occur at 340 nm. In conclusion, the light emission at specific wavelengths was found to depend upon the incident proton fluence and the proton energy. The wavelengths of the emitted light measured in this study have significance for the understanding of radiation induced bystander effects.

  16. Antigenotoxic potential of Asparagus racemosus root extract against electron beam radiation induced micronuclei formation in Swiss albino mice

    International Nuclear Information System (INIS)

    Bhandary, B. Satheesh Kumar; Sharmila, K.P.; Suchetha Kumari, N.; Bhat, Vadish S.; Shetty, Jayaram; Peter, Alex John; Jose, Jerish M.; Fernandes, Ronald

    2016-01-01

    To evaluate the antigenotoxic potential of Asparagus Racemosus Root ethanolic extract (ARE) against electron beam radiation induced micronuclei formation in Swiss albino mice. Micronucleus assay was performed in the bone marrow of Swiss albino mice according to the method of Hosseinimehr et al., 2003. The experimental animals were orally administered 200 mg/kg body weight of ARE once daily for 15 consecutive days. At the end of experimental period, the animals were euthanized and the bone marrow was collected from the femur. Control (C), Radiation control (RC) and drug control (DC) group was also maintained. The number of radiation induced Micronucleated Polychromatic Erythrocytes (MnPCE) and Micronucleated Normochromatic Erythrocytes were decreased in the ARE treated mice which was statistically significant (p<0.05) compared to radiation control group. Present findings demonstrate the antigenotoxic potential of ARE against electron beam radiation induced micronuclei formation which may be attributed to scavenging of radiation-induced free radicals

  17. Concomitant pilocarpine during head and neck irradiation is associated with decreased posttreatment xerostomia

    International Nuclear Information System (INIS)

    Zimmerman, Robert P.; Mark, Rufus J.; Tran, Luu M.; Juillard, Guy F.

    1997-01-01

    Purpose: To retrospectively compare subjective postirradiation xerostomia scores of patients who received concomitant oral pilocarpine during radiotherapy for head and neck cancer and 3 months thereafter with those of similar cohorts who did not receive pilocarpine. Methods and Materials: Subjective xerostomia was assessed using a visual analog scale xerostomia questionnaire that measured oral dryness, oral comfort, difficulty with sleep, speech, and eating. The concomitant pilocarpine group had both parotid glands in the initial field treated to at least 45 Gy and received 5 mg pilocarpine hydrochloride four times per day (q.i.d.) beginning on the first day of radiotherapy and continuing for 3 months after completion of radiation. The control cohort had also received at least 45 Gy to both parotid glands and had not received pilocarpine at the time of evaluation. Scores on the visual analog scale were averaged and compared using the Student's t-test. Results: Seventeen patients who received concomitant pilocarpine during head and neck irradiation and 18 patients who had not been treated with pilocarpine were available for follow-up. The mean intervals between completion of radiation and evaluation of xerostomia were 17 months and 16 months, respectively. Only one of the pilocarpine-treated patients was still taking pilocarpine at the time of evaluation. For each of the individual components of xerostomia scored on the visual analog scale, as well as the composite of all components, the group that had received oral pilocarpine during radiation had significantly less xerostomia (p < 0.01 for each). Conclusions: The use of 5 mg oral pilocarpine q.i.d. during radiotherapy for head and neck cancer and 3 months thereafter was associated with significantly less subjective xerostomia than that reported by a similar cohort of patients who had not received pilocarpine. The continued use of pilocarpine does not appear to be necessary to maintain this benefit in most patients

  18. Antiseptic mouthwashes could worsen xerostomia in patients taking polypharmacy.

    Science.gov (United States)

    Chevalier, Marlene; Sakarovitch, Charlotte; Precheur, Isabelle; Lamure, Julie; Pouyssegur-Rougier, Valerie

    2015-05-01

    Polypharmacy is a common cause of xerostomia. This study aimed to investigate whether xerostomia could be an adverse drug event of mouthwashes, when they are used for longer than 2 weeks by patients taking polypharmacy. This cross-sectional observational study included 120 hospitalized patients (60 middle-aged and 60 elderly patients), taking polypharmacy (≥4 drugs daily) and at risk of drug-induced xerostomia. Xerostomia was assessed by questioning participants. A total of 62.5% of patients complained of xerostomia. In the middle-aged group (mean age=44.0 (8.7) years; 35.0% women) xerostomia seemed independently associated to mouthwashes, at the limit of significance (OR=5.00, 95% CI=0.99-25.3, p=0.052). Active principles in mouthwashes were mainly quaternary ammonium compounds (91.9%). Mouthwashes may disturb the healthy balance of the biofilm moisturizing the oral mucosa. The biofilm contains mucins, salivary glycoproteins with oligosaccharides side chains able to sequester water and endogenous bacteria surrounded by a glycocalyx. Oral bacteria are fully susceptible to quaternary ammonium (chlorhexidine, hexetidine, cetylpyridinium chloride) and to other antiseptics used in mouthwashes, such as betain, resorcin, triclosan, essential oils and alcohol. However, caregivers currently recommend such dental plaque control products to patients suffering from xerostomia in order to reduce the risk of caries and periodontitis. This study is the first report that use of antiseptic mouthwashes for more than 2 weeks could worsen xerostomia in patients taking polypharmacy. Oral care protocols should avoid this iatrogenic practice, particularly when xerostomia alters the quality-of-life and worsens malnutrition.

  19. Radiotherapy induced xerostomia: mechanisms, diagnostics, prevention and treatment--evidence based up to 2013.

    Science.gov (United States)

    Kałużny, Jarosław; Wierzbicka, Małgorzata; Nogala, Hanna; Milecki, Piotr; Kopeć, Tomasz

    2014-01-01

    Definition and prevalence of xerostomia were shortly presented. Radiosensitivity of the salivary glands, mechanism, diagnostics, and possible prediction methods of the intensity of xerostomia in the pre-radiotherapy period are widely discussed. Prevention of xerostomia: salivary gland sparing radiotherapy, cytoprotective agents, preservation by stimulation with cholinergic muscarinic agonists, surgical transfer of submandibular glands according to ASCO Management Guidelines and Quality of Life Recommendations were cited. Oral Care Study Group (2010) therapeutic approaches for relieving xerostomia are referred. Current therapies, restricted to symptom relief such as oral hygiene with fluoride agents, antimicrobials to prevent dental caries, saliva substitutes to relieve symptoms, and sialogenic agents to stimulate saliva were also discussed. Copyright © 2013 Polish Otorhinolaryngology - Head and Neck Surgery Society. Published by Elsevier Urban & Partner Sp. z.o.o. All rights reserved.

  20. A systematic review of salivary gland hypofunction and xerostomia induced by cancer therapies: management strategies and economic impact

    DEFF Research Database (Denmark)

    Jensen, Siri Beier; Pedersen, Anne Marie Lynge; Vissink, Arjan

    2010-01-01

    , amifostine, muscarinic agonist stimulation, oral mucosal lubricants, acupuncture, and submandibular gland transfer. There is evidence that salivary gland hypofunction and xerostomia induced by cancer therapies can be prevented or symptoms be minimized to some degree, depending on the type of cancer treatment....... Management guideline recommendations are provided for IMRT, amifostine, muscarinic agonist stimulation, oral mucosal lubricants, acupuncture, and submandibular gland transfer. Fields of sparse literature identified included effects of gustatory and masticatory stimulation, specific oral mucosal lubricant...... formulas, submandibular gland transfer, acupuncture, hyperbaric oxygen treatment, management strategies in pediatric cancer populations, and the economic consequences of salivary gland hypofunction and xerostomia...

  1. Radiation-Induced Graft Polymerization: Gamma Radiation and Electron Beam Technology for Materials Development

    International Nuclear Information System (INIS)

    Madrid, Jordan F.; Cabalar, Patrick Jay; Lopez, Girlie Eunice; Abad, Lucille V.

    2015-01-01

    The formation of functional hybrid materials by attaching polymer chains with advantageous tailored properties to the surface of a base polymer with desirable bulk character is an attractive application of graft copolymerization. Radiation-induced graft polymerization (RIGP) has been a popular approach for surface modification of polymers because of its merits over conventional chemical processes. RIGP, which proceeds primarily via free radical polymerization process, has the advantages such as simplicity, low cost, control over process and adjustment of the materials composition and structure. RIGP can be performed using either electron beam or gamma radiation and it can be applied to both synthetic and natural polymers. These merits make RIGP a popular research topic worldwide. Moreover, the materials synthesized and produced via RIGP has found applications, and were proposed to produce continuous impact, in the fields of medicine, agriculture, pollution remediation, rare earth and valuable metals recovery, fuel cell membrane synthesis and catalysis to name a few. From 2012 our group has performed electron beam and gamma radiation-induced graft polymerization of various monomers onto polymers of natural and synthetic origins (e.g. monomers - glycidyl methacrylate, styrene, acrylonitrile, N,N-dimethylaminoethyl methacrylate; base polymers – polyethylene/polypropylene nonwoven fabric, polypropylene nonwoven fabric pineapple fibers, cellulose nonwoven fabric microcrystalline cellulose). We tested these grafted materials for heavy metals (Pb, Ni, Cu) and organic molecule removal from aqueous solutions and E. coli activity (using reversible addition fragmentation chain transfer RAFT mediated grafting). The results clearly showed the success of materials modified via FIGP in these applications. Currently, we are studying the applications of grafted materials on treatment of waste waters from tanning industry, value addition to abaca nonwoven fabrics cell sheet

  2. Xerostomia health-related quality of life: NRG oncology RTOG 0537.

    Science.gov (United States)

    Wyatt, Gwen; Pugh, Stephanie L; Wong, Raimond K W; Sagar, Stephen; Singh, Anurag K; Koyfman, Shlomo A; Nguyen-Tân, Phuc F; Yom, Sue S; Cardinale, Francis S; Sultanem, Khalil; Hodson, Ian; Krempl, Greg A; Lukaszczyk, Barbara; Yeh, Alexander M; Berk, Lawrence

    2016-09-01

    The purpose of this secondary analysis was to determine change in overall health-related quality of life (HRQOL) based on patient data obtained from NRG Oncology RTOG 0537 as measured by the RTOG-modified University of Washington Head and Neck Symptom Score (RM-UWHNSS). A multi-site prospective randomized clinical trial design stratified 137 patients with post-radiation therapy xerostomia according to prior pilocarpine (PC) treatment and time after radiation therapy and/or chemotherapy and randomized patients into two groups. Patients were assigned to acupuncture or PC. Twenty-four sessions of acupuncture-like transcutaneous electrical nerve stimulation (ALTENS) were administered over 12 weeks, or oral PC (5 mg) three times daily over the same 12 weeks. The RM-UWHNSS was administered at baseline and at 4, 6, 9, and 15 months after the date of randomization. There were no between-arm differences in change scores on the RM-UWHNSS in the individual items, total score, or factor scores. For statistical modeling, race and time were significant for all outcomes (total and factor scores), while treatment arm was not significant. The ALTENS arm showed greater yet nonsignificant improvement in outcomes compared to the PC arm. Although no significant treatment differences were seen in this trial, patients receiving ALTENS consistently had lower scores, indicating better function, as compared to those receiving PC. Radiation-induced xerostomia improved over time for all patients.

  3. WE-D-210-04: Radiation-Induced Polymerization of Ultrasound Contrast Agents in View of Non-Invasive Dosimetry in External Beam Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Callens, M; Verboven, E; Van Den Abeele, K [Department of Physics, Wave Propagation and Signal Processing, KU Leuven KULAK, Kortrijk (Belgium); D’Agostino, E [DoseVue NV, Hasselt (Belgium); Pfeiffer, H [Department of Materials Engineering, KU Leuven, Leuven (Belgium); D’hooge, J [Department of Cardiovascular Sciences, Bio-Medical Science Group, KU Leuven, Leuven (Belgium)

    2015-06-15

    Purpose: Ultrasound contrast agents (UCA’s) based on gas-filled microbubbles encapsulated by an amphiphilic shell are well established as safe and effective echo-enhancers in diagnostic imaging. In view of an alternative application of UCA’s, we investigated the use of targeted microbubbles as radiation sensors for external beam radiation therapy. As radiation induces permanent changes in the microbubble’s physico-chemical properties, a robust measure of these changes can provide a direct or indirect estimate of the applied radiation dose. For instance, by analyzing the ultrasonic dispersion characteristics of microbubble distributions before and after radiation treatment, an estimate of the radiation dose at the location of the irradiated volume can be made. To increase the radiation sensitivity of microbubbles, polymerizable diacetylene molecules can be incorporated into the shell. This study focuses on characterizing the acoustic response and quantifying the chemical modifications as a function of radiation dose. Methods: Lipid/diacetylene microbubbles were irradiated with a 6 MV photon beam using dose levels in the range of 0–150 Gy. The acoustic response of the microbubbles was monitored by ultrasonic through-transmission measurements in the range of 500 kHz to 20 MHz, thereby providing the dispersion relations of the phase velocity, attenuation and nonlinear coefficient. In addition, the radiation-induced chemical modifications were quantified using UV-VIS spectroscopy. Results: UV-VIS spectroscopy measurements indicate that ionizing radiation induces the polymerization of diacetylenes incorporated in the microbubble shell. The polymer yield strongly depends on the shell composition and the radiation-dose. The acoustic response is inherently related to the visco-elastic properties of the shell and is strongly influenced by the shell composition and the physico-chemical changes in the environment. Conclusion: Diacetylene-containing microbubbles are

  4. Shortening the Xerostomia Inventory

    Science.gov (United States)

    Thomson, William Murray; van der Putten, Gert-Jan; de Baat, Cees; Ikebe, Kazunori; Matsuda, Ken-ichi; Enoki, Kaori; Hopcraft, Matthew; Ling, Guo Y

    2011-01-01

    Objectives To determine the validity and properties of the Summated Xerostomia Inventory-Dutch Version in samples from Australia, The Netherlands, Japan and New Zealand. Study design Six cross-sectional samples of older people from The Netherlands (N = 50), Australia (N = 637 and N = 245), Japan (N = 401) and New Zealand (N = 167 and N = 86). Data were analysed using the Summated Xerostomia Inventory-Dutch Version. Results Almost all data-sets revealed a single extracted factor which explained about half of the variance, with Cronbach’s alpha values of at least 0.70. When mean scale scores were plotted against a “gold standard” xerostomia question, statistically significant gradients were observed, with the highest score seen in those who always had dry mouth, and the lowest in those who never had it. Conclusion The Summated Xerostomia Inventory-Dutch Version is valid for measuring xerostomia symptoms in clinical and epidemiological research. PMID:21684773

  5. The prevention and treatment of radiotherapy - induced xerostomia

    NARCIS (Netherlands)

    Eisbruch, Avraham; Rhodus, Nelson; Rosenthal, David; Murphy, Barbara; Rasch, Coen; Sonis, Stephen; Scarantino, Charles; Brizel, David

    2003-01-01

    Efforts to reduce the severity of postradiotherapy xerostomia include the use of salivary substitutes to gain symptomatic relief, salivary gland stimulants, agents delivered to protect the glands during radiotherapy (RT), and physical means to partially spare the major salivary glands from RT while

  6. Progress report on the neutral beam radiation hardening study

    International Nuclear Information System (INIS)

    Lee, J.D.; Condit, R.H.; Hoenig, C.L.; Wilcox, T.P.; Erickson, J.

    1978-01-01

    A neutral beam injector as presently conceived directly views the plasma it is sustaining. In turn the injector is exposed to the primary fusion neutrons plus secondary neutrons and gammas streaming back up the neutral beam duct. The intent of this work is to examine representative beam lines to see how performance and lifetimes could be affected by this radiation environment and to determine how unacceptable effects could be alleviated. Potential radiation induced problems addressed in this report have been limited to: (1) overheating of cryopanels and insulators, (2) gamma flux induced electrical conductivity increase of insulators, and (3) neutron and gamma fluence induced damage to insulator materials

  7. Evaluation of xerostomia following intensity modulated radiotherapy (IMRT) for head and neck cancer patients

    International Nuclear Information System (INIS)

    Lee, Seok Ho; Kim, Tae Hyun; Chie, Eui Kyu

    2004-01-01

    This study was done to evaluate xerostomia following intensity modulated radiotherapy for patients with head and neck cancer, and to analyze the correlation between the dosimetric parameters and xerostomia parameters. From February till October 2003, 13 patients with 3 months of follow-up were evaluated for xerostomia after being treated for head and neck cancer with IMRT. Their median age was 57 years (range:43 ∼ 77). Xerostomia were assessed with a 4-question xerostomia questionnaire score (XQS) and a test for salivary flow rates (unstimulated and stimulated). The patients were also given a validated LENT SOMA scale (LSC) questionnaire. The evaluations were completed before radiation therapy (pre-RT) and at 1 and. 3 months after radiation therapy (RT). We evaluated xerostomia at pre-RT, 1 and, 3 months after RT. The association between the xerostomia parameters (XQS and LSC) and salivary flow rates (unstimulated and stimulated: USFR and SSFR) was assessed at 1 and 3 months after RT. All 13 patients showed no significant changes in XQS, LSC and Salivary Flow rates. As a result, we couldn't find out about xerostomia development. Based on the total mean parotid dose, 3,500 cGy, we divided these patients into two groups. The 8 patients (< 3,500 cGy) showed no significant changes in XQS, LSC and Salivary Flow rates. However, in 5 patients (≥ 3,500 cGy), there was a significant increase in USFR and, SSFR at 3 months after RT, and for the XQS and, LSC at 1 and 3 months after RT. The correlation between XQS and, LSC, and USFR and, SSFR in all patients (13) was significant at 3 months after RT. The correlation had a tendency to the decrease for USFR and, SSFR in proportion to the increase of XQS and, LSC. Base on the results of this study, IMRT seem to be an effective treatment to significantly decrease the xerostomia. XQS and, LSC seem to be a effective tool for predicting the xerostomia. A total parotid gland mean dose of < 3,500 cGy should be a planning goal if

  8. Crosslinking of oriented polyethylene by electron beam radiation. Influence of morphology induced by drawing

    International Nuclear Information System (INIS)

    Aerle, N.A.J.M. van; Crevecoeur, G.; Lemstra, P.J.

    1988-01-01

    The influence of drawing on the crosslinking efficiency for electron beam radiation is reported for solution-crystallized ultra-high molecular weight polyethylene. A maximum in crosslinking efficiency is found at a draw ratio of approximately five, indicating an optimum morphology for inducing crosslinks during the hot-drawing process. (author)

  9. Radioprotective efficacy of bisarylidene cyclopentanone on electron beam radiation induced oxidative stress in Drosophila melanogaster

    International Nuclear Information System (INIS)

    Darshan Raj, C.G.; Sarojini, B.K.; Musthafa Khaleel, V.; Ramesh, S.R.; Ramakrishna, M.K.; Narayana, B.; Sanjeev, Ganesh

    2010-01-01

    Present study was carried out for evaluating the radioprotective effect of bischalcone (2E, 5E) - 2,5-bis (3-methoxy-4-hydroxy-benzylidene) cyclopentanone (curcumin analog (CA)), on electron beam radiation induced oxidative stress in Drosophila melanogaster adults. The oxidative stress markers and antioxidants included superoxide dismutase (SOD) and catalase (CAT). The oxidative stress was induced at 1.5 Gy. (author)

  10. Parotid gland mean dose as a xerostomia predictor in low-dose domains.

    Science.gov (United States)

    Gabryś, Hubert Szymon; Buettner, Florian; Sterzing, Florian; Hauswald, Henrik; Bangert, Mark

    2017-09-01

    Xerostomia is a common side effect of radiotherapy resulting from excessive irradiation of salivary glands. Typically, xerostomia is modeled by the mean dose-response characteristic of parotid glands and prevented by mean dose constraints to either contralateral or both parotid glands. The aim of this study was to investigate whether normal tissue complication probability (NTCP) models based on the mean radiation dose to parotid glands are suitable for the prediction of xerostomia in a highly conformal low-dose regime of modern intensity-modulated radiotherapy (IMRT) techniques. We present a retrospective analysis of 153 head and neck cancer patients treated with radiotherapy. The Lyman Kutcher Burman (LKB) model was used to evaluate predictive power of the parotid gland mean dose with respect to xerostomia at 6 and 12 months after the treatment. The predictive performance of the model was evaluated by receiver operating characteristic (ROC) curves and precision-recall (PR) curves. Average mean doses to ipsilateral and contralateral parotid glands were 25.4 Gy and 18.7 Gy, respectively. QUANTEC constraints were met in 74% of patients. Mild to severe (G1+) xerostomia prevalence at both 6 and 12 months was 67%. Moderate to severe (G2+) xerostomia prevalence at 6 and 12 months was 20% and 15%, respectively. G1 + xerostomia was predicted reasonably well with area under the ROC curve ranging from 0.69 to 0.76. The LKB model failed to provide reliable G2 + xerostomia predictions at both time points. Reduction of the mean dose to parotid glands below QUANTEC guidelines resulted in low G2 + xerostomia rates. In this dose domain, the mean dose models predicted G1 + xerostomia fairly well, however, failed to recognize patients at risk of G2 + xerostomia. There is a need for the development of more flexible models able to capture complexity of dose response in this dose regime.

  11. Unilateral versus bilateral irradiation in squamous cell head and neck cancer in relation to patient-rated xerostomia and sticky saliva

    International Nuclear Information System (INIS)

    Jellema, Anke Petra; Slotman, Ben J.; Doornaert, Patricia; Leemans, C. Rene; Langendijk, Johannes A.

    2007-01-01

    Background and purpose: To investigate the association between radiation technique with patient-rated moderate and severe xerostomia and sticky saliva. Materials and methods: One hundred and fifty patients treated with bilateral or unilateral irradiation for head and neck cancer were included. The salivary glands and the oral cavity were delineated on plannings-CT scans. Xerostomia and sticky saliva were assessed using the EORTC QLQ-H and N35 questionnaire at baseline and 6 and 12 months. Results: At 6 months a significant association between radiation technique and the mean parotid dose (MD parb ) and xerostomia was observed (Odds ratio (OR)-technique: 2.55; p = 0.04 and OR-MD parb : 1.04; p = 0.009). Considering the individual salivary glands, only the mean dose in the contralateral parotid gland (MD parcl ) is associated with xerostomia (OR: 1.04; p parb influence the risk of xerostomia in irradiated patients. Of all individual salivary glands, only MD parcl is of utmost importance for xerostomia. The shift in the P50 observed for xerostomia suggests that sparing of the contralateral parotid gland is compensated by hyperfunction of the contralateral parotid gland

  12. Metabolic Imaging Biomarkers of Postradiotherapy Xerostomia

    International Nuclear Information System (INIS)

    Cannon, Blake; Schwartz, David L.; Dong Lei

    2012-01-01

    Purpose: Xerostomia is a major complication of head and neck radiotherapy (RT). Available xerostomia measures remain flawed. [ 18 F]fluorodeoxyglucose-labeled positron emission tomography-computed tomography (FDG-PET-CT) is routinely used for staging and response assessment of head and neck cancer. We investigated quantitative measurement of parotid gland FDG uptake as a potential biomarker for post-RT xerostomia. Methods and Materials: Ninety-eight locally advanced head and neck cancer patients receiving definitive RT underwent baseline and post-RT FDG-PET-CT on a prospective imaging trial. A separate validation cohort of 14 patients underwent identical imaging while prospectively enrolled in a second trial collecting sialometry and patient-reported outcomes. Radiation dose and pre- and post-RT standard uptake values (SUVs) for all voxels contained within parotid gland ROI were deformably registered. Results: Average whole-gland or voxel-by-voxel models incorporating parotid D Met (defined as the pretreatment parotid SUV weighted by dose) accurately predicted posttreatment changes in parotid FDG uptake (e.g., fractional parotid SUV). Fractional loss of parotid FDG uptake closely paralleled early parotid toxicity defined by posttreatment salivary output (p Met may potentially be used to guide function-sparing treatment planning. Prospective validation of FDG-PET-CT as a convenient, quantifiable imaging biomarker of parotid function is warranted and ongoing.

  13. Radiation monitoring and beam dump system of the OPAL silicon microvertex detector

    CERN Document Server

    Braibant, S

    1997-01-01

    The OPAL microvertex silicon detector radiation monitoring and beam dump system is described. This system was designed and implemented in order to measure the radiation dose received at every beam crossing and to induce a fast beam dump if the radiation dose exceeds a given threshold.

  14. A Guide to Medications Inducing Salivary Gland Dysfunction, Xerostomia, and Subjective Sialorrhea: A Systematic Review Sponsored by the World Workshop on Oral Medicine VI.

    Science.gov (United States)

    Wolff, Andy; Joshi, Revan Kumar; Ekström, Jörgen; Aframian, Doron; Pedersen, Anne Marie Lynge; Proctor, Gordon; Narayana, Nagamani; Villa, Alessandro; Sia, Ying Wai; Aliko, Ardita; McGowan, Richard; Kerr, Alexander Ross; Jensen, Siri Beier; Vissink, Arjan; Dawes, Colin

    2017-03-01

    Medication-induced salivary gland dysfunction (MISGD), xerostomia (sensation of oral dryness), and subjective sialorrhea cause significant morbidity and impair quality of life. However, no evidence-based lists of the medications that cause these disorders exist. Our objective was to compile a list of medications affecting salivary gland function and inducing xerostomia or subjective sialorrhea. Electronic databases were searched for relevant articles published until June 2013. Of 3867 screened records, 269 had an acceptable degree of relevance, quality of methodology, and strength of evidence. We found 56 chemical substances with a higher level of evidence and 50 with a moderate level of evidence of causing the above-mentioned disorders. At the first level of the Anatomical Therapeutic Chemical (ATC) classification system, 9 of 14 anatomical groups were represented, mainly the alimentary, cardiovascular, genitourinary, nervous, and respiratory systems. Management strategies include substitution or discontinuation of medications whenever possible, oral or systemic therapy with sialogogues, administration of saliva substitutes, and use of electro-stimulating devices. While xerostomia was a commonly reported outcome, objectively measured salivary flow rate was rarely reported. Moreover, xerostomia was mostly assessed as an adverse effect rather than the primary outcome of medication use. This study may not include some medications that could cause xerostomia when administered in conjunction with others or for which xerostomia as an adverse reaction has not been reported in the literature or was not detected in our search. We compiled a comprehensive list of medications with documented effects on salivary gland function or symptoms that may assist practitioners in assessing patients who complain of dry mouth while taking medications. The list may also prove useful in helping practitioners anticipate adverse effects and consider alternative medications.

  15. Effect of low-level laser therapy on radiotherapy-induced hyposalivation and xerostomia: a pilot study.

    Science.gov (United States)

    Saleh, Jamil; Figueiredo, Maria Antonia Zancanaro; Cherubini, Karen; Braga-Filho, Aroldo; Salum, Fernanda Gonçalves

    2014-10-01

    The present pilot study aimed to assess the effect of low-level laser therapy (LLLT) on hyposalivation and xerostomia as a consequence of head and neck radiotherapy. The benefits of LLLT in salivary flow have been shown; however, there are no studies investigating its effects on patients who have already undergone radiotherapy and present hyposalivation and xerostomia as a sequela. Twenty-three patients with a history of head and neck malignancy, who were treated by fractioned teletherapy (dosimetry ranging from 45 to 70 Gy) in the cervicofacial region were selected. They all presented with xerostomia and severe hyposalivation. Patients were randomly distributed into a laser group (n=12) and a control group (n=11). A GaAlAs laser (830 nm, 100 mW, illuminated area 0.028 cm2, 3.57 W/cm2, 20 sec, 2.0 J, 71 J/cm2) was used punctually in the major salivary glands, twice a week for 6 weeks, with a 12 session total. Stimulated and unstimulated salivary flow rate (SFR) were assessed, as well as the xerostomia and quality of life related to oral health (QLROH). The analysis did not show any significant difference between the groups with regards to the SFR and xerostomia, and the QLROH. However, at the end of the treatment, the xerostomia and the QLROH showed significant improvement in both groups compared with assessments performed at baseline, highlighting the importance of advice given to the irradiated patients, and their follow-up. With the parameters used, LLLT was not able to increase SFR or decrease xerostomia. The results may be associated with the late effects of radiotherapy on glandular structure, such as fibrosis and acinar atrophy.

  16. Effect of electron beam radiations on anxiety in experimental animal models

    International Nuclear Information System (INIS)

    Deepa, B; Suchetha Kumari; Sanjeev, Ganesh; Rao, Satheesh

    2013-01-01

    Exposures to ionizing radiation have been an inevitable part of the environment. This type of radiation can disrupt atoms, creating positive and negative charged particles, and cause biological harm. Ionizing radiation includes X-rays, gamma rays, alpha particles, beta particles and neutrons. They have the potential to cause both beneficial and harmful effects. There are concerns about these radiations as they are widely used in hospitals for treatment and diagnosis of various diseases. The present work was designed to test the effect of whole body electron beam radiation on anxiety in mice using the Elevated plus maze and Light dark arena, the commonly used models for assessing anxiety in rodents. Mice were irradiated with three different doses (2 Gy, 4 Gy and 6 Gy) of electron beam radiations. Statistical analysis revealed that whole body irradiation of the moderate dose range (2-6 Gy) of electron beam leads to a significant (p<0.001) anxiogenic activity in irradiated mice. Electron beam induced anxiety can be due to radiation induced reactive oxygen species in brain. (author)

  17. Impact of radiation-induced xerostomia on quality of life after primary radiotherapy among patients with head and neck cancer

    NARCIS (Netherlands)

    Jellema, Anke Petra; Slotman, Ben J.; Doornaert, Patricia; Leemans, C. Rene; Langendijk, Johannes A.

    2007-01-01

    Purpose: To investigate the impact of xerostomia on overall quality of life (QoL) outcome and related dimensions among bead and neck cancer patients treated with primary radiotherapy. Methods and Materials: A total of 288 patients with Stage I-IV disease without distant metastases were included.

  18. Etiology, evaluation, and management of xerostomia.

    Science.gov (United States)

    Millsop, Jillian W; Wang, Elizabeth A; Fazel, Nasim

    Xerostomia is defined as the complaint of oral dryness. It is a condition that primarily affects older adults and can have a significant negative effect on one's quality of life. Patients with xerostomia often do not have objective signs of hyposalivation. The underlying etiology of xerostomia includes a variety of systemic diseases and local factors. Our aim is to provide a comprehensive review of the differential diagnosis, evaluation, and management of xerostomia. Prompt diagnosis and management can alleviate the clinical manifestations of this debilitating condition. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Xerostomia among older home care clients.

    Science.gov (United States)

    Viljakainen, Sari; Nykänen, Irma; Ahonen, Riitta; Komulainen, Kaija; Suominen, Anna Liisa; Hartikainen, Sirpa; Tiihonen, Miia

    2016-06-01

    The purpose of this study was to examine drug use and other factors associated with xerostomia in home care clients aged 75 years or older. The study sample included 270 home care clients aged ≥75 years living in Eastern and Central Finland. The home care clients underwent in-home interviews carried out by trained home care nurses, nutritionists, dental hygienists and pharmacists. The collected data contained information on sociodemographic factors, health and oral health status, drug use, depressive symptoms (GDS-15), cognitive functioning (MMSE), functional ability (Barthel Index, IADL) and nutrition (MNA). The primary outcome was xerostomia status (never, occasionally or continuously). Among the home care clients, 56% (n = 150) suffered from xerostomia. Persons with continuous xerostomia used more drugs and had more depressive symptoms and a higher number of comorbidities than other home care clients. In multivariate analyses, excessive polypharmacy (OR = 1.83, 95% Cl 1.08-3.10) and depressive symptoms (OR = 1.12, 95% Cl 1.03-1.22) were associated with xerostomia. Xerostomia is a common problem among old home care clients. Excessive polypharmacy, use of particular drug groups and depressive symptoms were associated with xerostomia. The findings support the importance of a multidisciplinary approach in the care of older home care clients. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  20. Computer modelling of radiation-induced bystander effect

    International Nuclear Information System (INIS)

    Khvostunov, Igor K.; Nikjoo, Hooshang

    2002-01-01

    Radiation-induced genomic instability and bystander effects are now well established consequences of exposure of living cells to ionising radiation. It has been observed that cells not directly hit by radiation tracks may still exhibit radiation effects. We present a quantitative modelling of the radiation-induced bystander effect based on a diffusion model of spreading the bystander signal. The model assumes the bystander factor to be a protein of low molecular weight, given out by the hit cell, diffusing in the medium and reacting with non-hit cells. The model calculations successfully predict the results of cell survival in an irradiated conditioned medium. The model predicts the shape of dose-effect relationship for cell survival and oncogenic transformation induced by broad-beam and micro-beam irradiation by alpha-particles. (author)

  1. Prevalence of Drug-Induced Xerostomia in Older Adults with Cognitive Impairment or Dementia: An Observational Study.

    Science.gov (United States)

    Gil-Montoya, José Antonio; Barrios, Rocío; Sánchez-Lara, Inés; Carnero-Pardo, Cristobal; Fornieles-Rubio, Francisco; Montes, Juan; Gonzalez-Moles, Miguel Angel; Bravo, Manuel

    2016-08-01

    Older adults, especially those with cognitive impairment or dementia, frequently consume drugs with potential xerostomic effects that impair their quality of life and oral health. The objective of this study was to determine the prevalence and analyze the possible pharmacological etiology of xerostomia in older people with or without cognitive impairment. Individuals with cognitive impairment were recruited from patients diagnosed using standardized criteria in two neurology departments in Southern Spain. A comparison group was recruited from healthcare centers in the same city after ruling out cognitive impairment. Data on oral health, xerostomia, and drug consumption were recorded in both groups. Dry mouth was evaluated using a 1-item questionnaire and recording clinical signs of oral dryness. All drugs consumed by the participants were recorded, including memantine, anticholinesterases, antipsychotics, antidepressants, and anxiolytics. The final sample comprised 200 individuals with mild cognitive impairment or dementia and 156 without. Xerostomia was present in 70.5 % of participants with cognitive impairment versus 36.5 % of those without, regardless of the drug consumed. Memantine consumption was the only variable significantly related to xerostomia in the multivariate model (OR 3.1; 95 % CI 1.1-8.7), and this relationship persisted after adjusting for possible confounders and forcing the inclusion of drugs with xerostomic potential. More than 70 % of participants diagnosed with cognitive impairment or dementia had xerostomia. Anticholinesterases and memantine were both associated with the presence of xerostomia. In the case of memantine, this association was independent of the consumption of the other drugs considered.

  2. Protective role of Carica papaya (Linn.) in electron beam radiation induced hematological and cytogenetic damages in Swiss albino mice

    International Nuclear Information System (INIS)

    Yogish Somayaji, T.; Suchetha Kumari, N.

    2014-01-01

    Carica papaya (Linn.) is known to possess various biomedical applications. It has remarkable antioxidant properties. The main objective of the study was to evaluate the leaf extracts of Carica papaya (Linn.) on hematologic and cytogenetic changes occurring due to irradiation of mice to sub-lethal doses of Electron Beam Radiation (EBR). Analysis of hematological changes occurring due to irradiation of mice to sub-lethal doses of EBR, and the effects of Carica papaya (Linn.) extract on the same. The Assessment of hematopoietic stress by spleen colony forming unit and spleen body weight index. The analysis of cell proliferation and immunomodulation with response to the effects of Carica papaya (Linn.) extract by estimation of IL-6. The estimation of serum total antioxidants, lipid peroxidation and analyzing the activities of enzymes like SOD, ALP, and AST. Male Swiss albino mice were fed orally with papaya aqueous leaf extract for 15 days. They were irradiated with a whole body dose of 6 Gy Electron Beam radiation. The mice were dissected for liver, kidney, bone marrow, spleen and brain. The hematological studies were done using blood cell count in an automated cell counter. The biochemical estimations like urea, creatinine, SGOT, SGPT, Total Protein, Albumin, Bilirubin were done using the serum and homogenates. The total antioxidant capacity, the antioxidant enzymes were estimated. The Interleukin-6 levels were estimated in serum to assess immune modulation. The results show a decrease in the hematological parameters in radiated animals. The papaya treated groups have shown modulation in the hematological parameters. The extract has also reduced the suppression of the bone marrow induced by radiation. The radiation induced liver damage is also reduced in papaya treated groups. The aqueous extract of Carica papaya (Linn.) has shown protective effects in electron beam radiation induced tissue damages in Swiss Albino mice (author)

  3. Analysis of radiation pressure force exerted on a biological cell induced by high-order Bessel beams using Debye series

    International Nuclear Information System (INIS)

    Li, Renxian; Ren, Kuan Fang; Han, Xiang'e; Wu, Zhensen; Guo, Lixin; Gong, Shuxi

    2013-01-01

    Debye series expansion (DSE) is employed to the analysis of radiation pressure force (RPF) exerted on biological cells induced by high-order Bessel beams (BB). The beam shape coefficients (BSCs) for high-order Bessel beams are calculated using analytical expressions obtained by the integral localized approximation (ILA). Different types of cells, including a real Chinese Hamster Ovary (CHO) cell and a lymphocyte which are respectively modeled by a coated and five-layered sphere, are considered. The RPF induced by high-order Bessel beams is compared with that by Gaussian beams and zeroth-order Bessel beams, and the effect of different scattering processes on RPF is studied. Numerical calculations show that high-order Bessel beams with zero central intensity can also transversely trap particle in the beam center, and some scattering processes can provide longitudinal pulling force. -- Highlights: ► BSCs for high-order Bessel beam (HOBB) is derived using ILA. ► DSE is employed to study the RPF induced by HOBB exerted on multilayered cells. ► RPF is decided by radius relative to the interval of peaks in intensity profile. ► HOBB can also transversely trap high-index particle in the vicinity of beam axis. ► RPF for some scattering processes can longitudinally pull particles back

  4. Xerostomia: An overview

    Directory of Open Access Journals (Sweden)

    Jitender Reddy Kubbi

    2015-01-01

    Full Text Available Xerostomia is a subjective sensation of dry mouth with objective evidence of decreased salivary flow. It is a multifactorial condition which increases the risk of oral diseases and has a significant effect on the person′s quality of life. So, these patients need special care for maintenance of oral and general health. We, being oral health care professionals, it is our responsibility to diagnose and treat the condition accordingly using a multidisciplinary approach. This paper enlightens the etiology and management of xerostomia.

  5. Natural products for the management of xerostomia: a randomized, double-blinded, placebo-controlled clinical trial.

    Science.gov (United States)

    Navarro Morante, Anabel; Wolff, Andy; Bautista Mendoza, Gloria Rocio; López-Jornet, Pia

    2017-02-01

    The aim of this study was to evaluate the clinical performance of lycopene-enriched virgin olive oil in spray form used to treat patients with drug-induced xerostomia, comparing this with a placebo spray. This double-blind, randomized clinical trial included elderly subjects with drug-induced xerostomia (n = 60). Resting salivary flow was measured using the draining technique. The Xerostomia Inventory (XI) was used to assess symptoms and the Oral Health Impact Profile 14 (OHIP-14) to assess patient quality of life. Evaluations were made before and after 12 weeks of product/placebo application. Sixty patients took part in the study. Symptoms improved among the treatment group (n = 30) after 12 weeks in the following XI domains: 'Rate the difficulty you experience in speaking because of dryness' (P = 0.03); 'Rate how much saliva is in your mouth' (P = 0.03); and 'Rate the dryness of your lips' (P = 0.04). The placebo group (n = 30) underwent improvements in: 'Rate how much saliva is in your mouth' (P = 0.02) and 'Rate the dryness of your mouth' (P = 0.01). A significant improvement (P = 0.001) in oral-related quality of life (OHIP-14) was identified in the treatment group, while no significant differences were observed in the placebo group (P > 0.05). The topical application of lycopene-enriched virgin olive oil and its placebo counterpart improved xerostomia-related symptoms significantly (but not salivary flow rate) in patients with drug-induced xerostomia. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. Expression of Wnt-1, TGF-β and related cell–cell adhesion components following radiotherapy in salivary glands of patients with manifested radiogenic xerostomia

    International Nuclear Information System (INIS)

    Hakim, Samer George; Ribbat, Julika; Berndt, Alexander; Richter, Petra; Kosmehl, Hartwig; Benedek, Geza A.; Jacobsen, Hans Christian; Trenkle, Thomas; Sieg, Peter; Rades, Dirk

    2011-01-01

    Background: Radiation-induced xerostomia still represents a common symptom following radiotherapy of head and neck malignancies, which significantly impairs the patient’s quality of life. In this cross-sectional study, human salivary glands were investigated to assess the role of Wnt/β-catenin and TGF-β pathways in the pathogenic process of radiogenic impairment of salivary function. Methods: Irradiated human salivary glands were investigated in patients with manifested xerostomia. Alteration of Wnt-1 and cell–cell adhesion was evaluated immunohistologically as well as changes in the expression of TGF-β were assessed in salivary gland tissue. Results: We assessed two alteration patterns in which Wnt-1 expression represents one change along with up-regulation of β-catenin and E-cadherin in irradiated but viable acinar cells. Increased expression of tenascin-C was observed in sites of epithelial–mesenchymal interaction and loss of cell–cell adhesion was assessed in translocated epithelial cells in the stroma. Conclusion: Increased transdifferentiation and remodeling of acinar structures was associated with decrease of viable acinar structures. The role of Wnt and TGF signaling may provide a potential therapeutic approach to prevent radiation-induced damage to salivary glands during radiotherapy for head and neck cancer.

  7. Preservation of beam loss induced quenches, beam lifetime and beam loss measurements with the HERA-p beam-loss-monitor system

    International Nuclear Information System (INIS)

    Wittenburg, K.

    1994-01-01

    The beam-loss-monitors (BLMs) in the HERA-Proton-ring (HERAp) must fulfil the following requirements: They have to measure losses sensitive and fast enough to prevent the superconducting magnets from beam loss induced quenching; the dynamic range of the monitors must exceed several decades in order to measure losses during beam lifetimes of hundreds of hours as well as the much stronger losses that may quench superconducting magnets; they have to be insensitive to the synchrotron radiation of the adjacent electron-ring (HERAe); and their radiation hardness must allow a monitor-lifetime of a few years of HERA operation. These requirements are well satisfied by the HERAp-BLM-System. (orig.)

  8. Relationship between xerostomia and gingival condition in young adults.

    Science.gov (United States)

    Mizutani, S; Ekuni, D; Tomofuji, T; Azuma, T; Kataoka, K; Yamane, M; Iwasaki, Y; Morita, M

    2015-02-01

    Xerostomia is a subjective symptom of dryness in the mouth. Although a correlation between xerostomia and oral conditions in the elderly has been reported, there are few such studies in the young adults. The aim of this study was to examine the relationship of xerostomia with the gingival condition in university students. A total of 2077 students (1202 male subjects and 875 female subjects), 18-24 years of age, were examined. The disease activity and severity of the gingival condition were assessed as the percentage of teeth with bleeding on probing (%BOP) and the presence of teeth with probing pocket depth of ≥ 4 mm, respectively. Additional information on xerostomia, oral health behaviors, coffee/tea intake and nasal congestion was collected via a questionnaire. Path analysis was used to test pathways from xerostomia to the gingival condition. One-hundred and eighty-three (8.8%) students responded that their mouths frequently or always felt dry. Xerostomia was related to %BOP and dental plaque formation, but was not related to the presence of probing pocket depth ≥ 4 mm. In the structural model, xerostomia was related to dental plaque formation (p Xerostomia was associated with coffee/tea intake (p Xerostomia was indirectly related to gingival disease activity through the accumulation of dental plaque. Nasal congestion and coffee/tea intake also affected xerostomia. These findings suggest that xerostomia should be considered in screening for gingivitis risk in young adults. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  9. Xerostomia, salivary characteristics and gland volumes following intensity-modulated radiotherapy for nasopharyngeal carcinoma: a two-year follow up.

    Science.gov (United States)

    Sim, Cpc; Soong, Y L; Pang, Epp; Lim, C; Walker, G D; Manton, D J; Reynolds, E C; Wee, Jts

    2018-03-23

    To evaluate changes in xerostomia status, salivary characteristics and gland volumes 2 years following radiotherapy in nasopharyngeal carcinoma patients. Xerostomia scores, salivary flow rates, pH and buffering capacity were measured at pre-radiotherapy, mid-radiotherapy, 2 weeks, 3 months and 2 years post-radiotherapy. Salivary gland volumes and their correlation with radiation dose were also assessed. Mean radiation dose to oral cavity, parotid and submandibular glands (SMG) was 44.5, 65.0 and 38.6 Gy respectively. Parotid and SMG volumes decreased 33% at 3 months post-radiotherapy; volumes at 2 years post-radiotherapy were 84% and 51% of pre-radiotherapy levels, respectively. Correlations were observed between parotid gland volume per cent reduction and its radiation dose and between resting salivary flow rate reduction and post-radiotherapy/pre-radiotherapy SMG volume ratio. Salivary flow rates and resting saliva pH remained significantly low at 2 years post-radiotherapy (both flow rates, P = 0.001; resting saliva pH, P = 0.005). Similarly, xerostomia scores remained significantly higher compared with pre-radiotherapy levels. Submandibular gland volumetric shrinkage persisted 2 years after radiotherapy. Xerostomia scores remained significantly higher, and salivary flow rates and resting saliva pH remained significantly lower, suggesting that study participants were still at risk for hyposalivation-related oral diseases. © 2018 Australian Dental Association.

  10. Validity and reliability of the Greek version of the xerostomia questionnaire in head and neck cancer patients.

    Science.gov (United States)

    Memtsa, Pinelopi Theopisti; Tolia, Maria; Tzitzikas, Ioannis; Bizakis, Ioannis; Pistevou-Gombaki, Kyriaki; Charalambidou, Martha; Iliopoulou, Chrysoula; Kyrgias, George

    2017-03-01

    Xerostomia after radiation therapy for head and neck (H&N) cancer has serious effects on patients' quality of life. The purpose of this study was to validate the Greek version of the self-reported eight-item xerostomia questionnaire (XQ) in patients treated with radiotherapy for H&N cancer. The XQ was translated into Greek and administered to 100 XQ patients. An exploratory factor analysis was performed. Reliability measures were calculated. Several types of validity were evaluated. The observer-rated scoring system was also used. The mean XQ value was 41.92 (SD 22.71). Factor analysis revealed the unidimensional nature of the questionnaire. High reliability measures (ICC, Cronbach's α, Pearson coefficients) were obtained. Patients differed statistically significantly in terms of XQ score, depending on the RTOG/EORTC classification. The Greek version of XQ is valid and reliable. Its score is well related to observer's findings and it can be used to evaluate the impact of radiation therapy on the subjective feeling of xerostomia.

  11. Evaluation of the oxidative stress induced by the electron beam radiation on various organs of Swiss Albino mice - in-vivo study

    International Nuclear Information System (INIS)

    Vishakh, R.; Moodithaya, Shailaja S.; Suchetha Kumari, N.; Sanjeev, Ganesh

    2014-01-01

    Radiation is one of the important threats in the modern world. Though the radiation injuries by natural means is very less common, advancement in the nuclear warfare research had increased the threat of radiation induced damage to biological system. Since years researchers are in search of a novel radio-protector, but without complete success. The reason behind may be its toxicity in higher doses. All the above research challenges lead many researchers to investigate radiation induced damage. Most of the studies had been done to investigate radiation induced damage in the lethal dose of radiation. But less work had been done to study the effect of radiation on tissues at sublethal dose. Therefore this study aims to evaluate the effect of radiation on the various organs in mice model. Swiss albino mice of 6 to 8 weeks old were divided into 2 groups i.e., Control, Radiation control with 6 mice in each group. 6 Gy sub lethal dose of electron beam radiation was used as radiation source. The liver, kidney and brain were dissected and used for biochemical analysis. The significant decrease in total antioxidant levels were observed in Liver and Kidney of irradiated mice, Glutathione levels were found to be decreased in Liver, Kidney and Brain, Glutathione S - transferase levels were found to be significantly decreased in Liver and Brain, Catalase activity was found to be decreased in Liver, Super oxide dismutase activity was found to be significantly decreased in Liver, Kidney and Brain homogenates when compared with the tissue homogenates of control group. From the results we can conclude that the liver is the most sensitive organ for the electron beam radiation induced oxidative stress when compared with Kidney and Brain. (author)

  12. The Treatment Outcome and Radiation-Induced Toxicity for Patients with Head and Neck Carcinoma in the IMRT Era: A Systematic Review with Dosimetric and Clinical Parameters

    Directory of Open Access Journals (Sweden)

    Vassilis Kouloulias

    2013-01-01

    Full Text Available A descriptive analysis was made in terms of the related radiation induced acute and late mucositis and xerostomia along with survival and tumor control rates (significance level at 0.016, bonferroni correction, for irradiation in head and neck carcinomas with either 2D Radiation Therapy (2DRT and 3D conformal (3DCRT or Intensity Modulated Radiation Therapy (IMRT. The mean score of grade > II xerostomia for IMRT versus 2-3D RT was 0.31 ± 0.23 and 0.56 ± 0.23, respectively (Mann Whitney, P<0.001. The parotid-dose for IMRT versus 2-3D RT was 29.56 ± 5.45 and 50.73 ± 6.79, respectively (Mann Whitney, P=0.016. The reported mean parotid-gland doses were significantly correlated with late xerostomia (spearman test, rho = 0.5013, P<0.001. A trend was noted for the superiority of IMRT concerning the acute oral mucositis. The 3-year overall survival for either IMRT or 2-3DRT was 89.5% and 82.7%, respectively (P=0.026, Kruskal-Wallis test. The mean 3-year locoregional control rate was 83.6% (range: 70–97% and 74.4 (range: 61–82%, respectively (P=0.025, Kruskal-Wallis. In conclusion, no significant differences in terms of locoregional control, overall survival and acute mucositis could be noted, while late xerostomia is definitely higher in 2-3D RT versus IMRT. Patients with head and neck carcinoma should be referred preferably to IMRT techniques.

  13. Prophylactic use of amifostine to prevent radiochemotherapy-induced mucositis and xerostomia in head-and-neck cancer

    International Nuclear Information System (INIS)

    Antonadou, Dosia; Pepelassi, Marizenia; Synodinou, Maria; Puglisi, Maria; Throuvalas, Nicolas

    2002-01-01

    Purpose: To determine the prophylactic properties of amifostine against acute and late toxicities from radiochemotherapy in patients with head-and-neck cancer. Methods and Materials: Fifty patients were randomized to receive conventional radiotherapy (RT) (2-Gy fractions, 5 days weekly, to a total of 60-74 Gy, depending on the tumor localization and TNM classification) and carboplatin (90 mg/m 2 infusion once per week before RT). Amifostine (300 mg/m 2 ) was administered in the study group only 15-30 min before RT for 6-7.5 weeks. The primary study end point was the grading of acute and late nonhematologic toxicities (mucositis, dysphagia, xerostomia) induced by radiochemotherapy. Secondary end points included treatment duration, hematologic toxicity, and clinical outcome. Results: The treatment duration was significantly shorter in the amifostine-treated group (p=0.013), because treatment interruptions were more frequent in the control group. Acute toxicities (mucositis and dysphagia) were less severe in the amifostine-treated group. By Week 3, all in the control group experienced Grade 2 mucositis compared with only 9% in the amifostine-treated group (p<0.0001). By Week 5, 52.2% of the patients in the control group experienced Grade 4 mucositis compared with 4.5% in the amifostine-treated group (p=0.0006). Similar results were obtained for dysphagia. At 3 months of follow-up, only 27% of patients in the study group experienced Grade 2 xerostomia compared with 73.9% in the control group (p=0.0001). Eighteen months after cessation of therapy, the proportion of patients with Grade 2 xerostomia was 4.5% vs. 30.4% for each respective treatment group (p=0.047). Cytoprotection with amifostine did not affect treatment outcome, with 90.9% complete responses in the amifostine-treated group compared with 78.3% in the control group (p=0.414). Conclusion: Amifostine was effective in reducing mucositis and dysphagia resulting from radiochemotherapy in patients with head

  14. Ion beam induced luminescence of germano-silicate optical fiber preform

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Hyunkyu; Kim, Jongyeol; Lee, Namho [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Kim, Youngwoong; Han, Wontaek [Gwangju Institute of Science and Technology, Gwangju (Korea, Republic of); Markovic, Nikola; Jaksic, Milko [Ruder Boskovic Institute, Zagred (Croatia)

    2014-05-15

    When an optical fiber is exposed to radiation, the attenuation (RIA, Radiation Induced Attenuation) in the optical fiber (OF) is increased because of the color centers which deteriorate the transmission property and generate the absorption loss. In order to understand the radiation induced defect, Ion Beam induced luminescence (IBIL) was introduced to investigate it. IBIL technique is to analyze IR/VIS/UV luminescence related to ion beam interaction with outer shell electrons involved in chemical bonds and structure defects of target atoms. So IBIL is sensitive to its chemical composition and has been used in analysis of material characterization, geological samples and cultural heritage objects. In silica material, four O atoms are surrounding one Si atom in tetrahedral coordination. In this study, the influence of Copper (Cu) and Cerium (Ce) dopants to germano silica core optical fibers were investigated under proton irradiation at RBI using Ion Beam induced luminescence (IBIL) method. To understand the radiation induced defect of optical fibers, IBIL were tested to a germano-silica core fiber under 2 MeV proton irradiation. Although a Cu or Ce dopant was not detected by IBIL technique, the relation between the amount of radiation and luminescence can be established. This experiment showed a potential technique of studying the effects and behavior of additive elements for silica core fiber. To increase the radiation resistance of optical fibers, further investigations are needed, i. e. the proper additives and its contents and an interaction mechanism between Ge-related defects and additives.

  15. Ion beam induced luminescence of germano-silicate optical fiber preform

    International Nuclear Information System (INIS)

    Jung, Hyunkyu; Kim, Jongyeol; Lee, Namho; Kim, Youngwoong; Han, Wontaek; Markovic, Nikola; Jaksic, Milko

    2014-01-01

    When an optical fiber is exposed to radiation, the attenuation (RIA, Radiation Induced Attenuation) in the optical fiber (OF) is increased because of the color centers which deteriorate the transmission property and generate the absorption loss. In order to understand the radiation induced defect, Ion Beam induced luminescence (IBIL) was introduced to investigate it. IBIL technique is to analyze IR/VIS/UV luminescence related to ion beam interaction with outer shell electrons involved in chemical bonds and structure defects of target atoms. So IBIL is sensitive to its chemical composition and has been used in analysis of material characterization, geological samples and cultural heritage objects. In silica material, four O atoms are surrounding one Si atom in tetrahedral coordination. In this study, the influence of Copper (Cu) and Cerium (Ce) dopants to germano silica core optical fibers were investigated under proton irradiation at RBI using Ion Beam induced luminescence (IBIL) method. To understand the radiation induced defect of optical fibers, IBIL were tested to a germano-silica core fiber under 2 MeV proton irradiation. Although a Cu or Ce dopant was not detected by IBIL technique, the relation between the amount of radiation and luminescence can be established. This experiment showed a potential technique of studying the effects and behavior of additive elements for silica core fiber. To increase the radiation resistance of optical fibers, further investigations are needed, i. e. the proper additives and its contents and an interaction mechanism between Ge-related defects and additives

  16. A Guide to Medications Inducing Salivary Gland Dysfunction, Xerostomia, and Subjective Sialorrhea : A Systematic Review Sponsored by the World Workshop on Oral Medicine VI

    NARCIS (Netherlands)

    Wolff, Andy; Joshi, Revan Kumar; Ekström, Jörgen; Aframian, Doron; Pedersen, Anne Marie Lynge; Proctor, Gordon; Narayana, Nagamani; Villa, Alessandro; Sia, Ying Wai; Aliko, Ardita; McGowan, Richard; Kerr, Alexander Ross; Jensen, Siri Beier; Vissink, Arjan; Dawes, Colin

    BACKGROUND: Medication-induced salivary gland dysfunction (MISGD), xerostomia (sensation of oral dryness), and subjective sialorrhea cause significant morbidity and impair quality of life. However, no evidence-based lists of the medications that cause these disorders exist. OBJECTIVE: Our objective

  17. Influence of intensity-modulated radiation therapy on parotid function in nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Cui Tiantian; Wu Shaoxiong; Han Fei; Lu Lixia; Huang Shaomin; Deng Xiaowu; Lu Taixiang; Zhao Chong

    2009-01-01

    Objective: To evaluate the effect of intensity-modulated radiation therapy (IMRT) on parotid function in nasopharyngeal carcinoma (NPC). Methods: Eighty-three NPC patients received prima- ry IMRT between 2001 and 2003. Xerostomia before radiotherapy, at the end of radiotherapy, at 6-month, 1-, 2-,3-,4- and 5-year after radiotherapy were investigated, respectively. The relation between xerostomia and parotid dose distribution was analyzed. Results: Of all the patients, 4, 31, 31 and 17 had stage I, II, III and IV A disease, respectively. Sixteen patients received chemo-radiotherapy. The median followed-up time was 65 months. The 5-year local control and regional control rate were 96% and 95%, respectively. The 5- year overall survival rate was 80%. The mild xerostomia rate at the seven time points was 42%, 51%, 71%, 77%, 58%, 38% and 26%. The corresponding moderate xerostomia rate was 52%, 53%, 21%, 8%, 3%, 2% and 2%, respectively. No serious xerostomia was observed. The mean dose of the bilateral parotid glands was 34.34 Gy. Xerostomia at 6-month after radiotherapy was positively correlated with the mean dose of the parotid glands, and D 50 was the independent factor in predicting the xerostomia. Parotid function was well protected when the mean dose and D 50 were no more than 33 Gy and 29 Gy, respectively. Conclusions: IMRT can improve the local-regional control of NPC and protect the parotid glands from radiation-induced injury. (authors)

  18. Prevalence of xerostomia in an adolescent inpatient psychiatric clinic: a preliminary study.

    Science.gov (United States)

    Kaur, Manvir; Himadi, Elaine; Chi, Donald L

    2016-01-01

    Adolescents with psychiatric conditions may be at risk for xerostomia. In this preliminary study, we estimated xerostomia prevalence in adolescents ages 9 to 17 years from an inpatient psychiatric clinic (N = 25) and examined whether: (1) gender and age were associated with xerostomia and (2) xerostomia was associated with self-reported cavities. We used a modified 11-item Xerostomia Index to identify xerostomia (no/yes) and asked if adolescents ever had or currently have cavities (no/yes). The mean age was 14 years (SD = 2.3) and 72% were male. Sixty percent reported xerostomia (SD = 50). There were no significant associations between xerostomia and gender (p = 0.99) or age (p = 0.66), or between xerostomia and past (p = 0.26) or current cavities (p = 0.11). Larger proportions of adolescents with xerostomia reported previous and current cavities. Sixty percent of adolescents from an inpatient psychiatric clinic reported having xerostomia, which may lead to increased caries risk over time. Additional research should examine the prevalence and consequences of xerostomia in high-risk adolescents. © 2015 Special Care Dentistry Association and Wiley Periodicals, Inc.

  19. Xerostomia and its predictors following parotid-sparing irradiation of head-and-neck cancer

    International Nuclear Information System (INIS)

    Eisbruch, Avraham; Kim, Hyungjin M.; Terrell, Jeffrey E.; Marsh, Lon H.C.; Dawson, Laura A.; Ship, Jonathan A.

    2001-01-01

    Purpose: To assess long-term xerostomia in patients receiving parotid-sparing radiation therapy (RT) for head-and-neck cancer, and to find the patient and therapy-related factors that affect its severity. Patients and Methods: From March 1994 through January 2000, 84 patients received comprehensive bilateral neck RT using conformal and multisegmental intensity-modulated RT (IMRT) aiming to spare the major salivary glands. Before RT and periodically through 2 years after the completion of RT, salivary flow rates from each of the major salivary glands were selectively measured. At the same time intervals, each patient completed an 8-item self-reported xerostomia-specific questionnaire (XQ). To gain a relative measure of the effect of RT on the minor salivary glands, whose output could not be measured, the surfaces of the oral cavity (extending to include the surface of the base of tongue) were outlined in the planning CT scans. The mean doses to the new organ ('oral cavity') were recorded. Forty-eight patients receiving unilateral neck RT were similarly studied and served as a benchmark for comparison. Factors predicting the XQ scores were analyzed using a random-effects model. Results: The XQ was found to be reliable and valid in measuring patient-reported xerostomia. The spared salivary glands which had received moderate doses in the bilateral RT group recovered to their baseline salivary flow rates during the second year after RT, and the spared glands in the unilateral RT group, which had received very low doses, demonstrated increased salivary production beyond their pre-RT levels. The increase in the salivary flow rates during the second year after RT paralleled an improvement in xerostomia in both patient groups. The improvement in xerostomia was faster in the unilateral compared with the bilateral RT group, but the difference narrowed at 2 years. The major salivary gland flow rates had only a weak correlation with the xerostomia scores. Factors found to be

  20. Dental patients' self-reports of xerostomia and associated risk factors.

    Science.gov (United States)

    Villa, Alessandro; Polimeni, Antonella; Strohmenger, Laura; Cicciù, Domenico; Gherlone, Enrico; Abati, Silvio

    2011-07-01

    Most studies regarding xerostomia focus on elderly people. Therefore, the authors conducted a study of dental patients 18 years or older to determine the prevalence of self-reported xerostomia and associated risk factors. The authors sent a total of 2,200 questionnaires to four dental clinics to assess patients' self-reported xerostomia. They also collected sociodemographic data and information regarding personal behavior. They used logistic regression models to estimate odds ratios (OR) and 95 percent confidence intervals (CI) to explore the relationship between self-reported xerostomia and risk factors that reasonably might be expected to be associated with self-reported xerostomia. The overall prevalence of xerostomia in participants was 7 percent. Participants with burning-mouth sensations were associated with having higher odds of experiencing dry mouth (OR, 2.1; 95 percent CI, 0.9-5.2). Participants 51 years or older were significantly more likely to report having dry mouth than were younger participants (P xerostomia increased with increasing numbers of medications patients reported using. The authors found that medication use and age were highly significant risk factors for dental patients reporting xerostomia. Clinicians should interview their patients carefully regarding their use of medications and provide proper oral health care to improve xerostomia resulting from medication use.

  1. Does hyperbaric oxygen treatment have the potential to increase salivary flow rate and reduce xerostomia in previously irradiated head and neck cancer patients? A pilot study

    DEFF Research Database (Denmark)

    Forner, Lone; Hansen, Ole Hyldegaard; von Brockdorff, Annet Schack

    2011-01-01

    in irradiated head and neck cancer patients. Eighty patients eligible for HBO treatment on the indication of prevention/treatment of osteoradionecrosis or soft tissue radiation injury were consecutively sampled, of whom 45 had hyposalivation (i.e. unstimulated whole saliva (UWS) flow rate......Irradiated head and neck cancer survivors treated in the Hyperbaric Oxygen (HBO) Unit, Copenhagen University Hospital, spontaneously reported improvement of radiation-induced dry mouth feeling. The aim of this pilot study was to evaluate salivary flow rate and xerostomia before and after HBO...

  2. Parotid gland sparing IMRT for head and neck cancer improves xerostomia related quality of life

    International Nuclear Information System (INIS)

    Rij, CM van; Oughlane-Heemsbergen, WD; Ackerstaff, AH; Lamers, EA; Balm, AJM; Rasch, CRN

    2008-01-01

    To assess the impact of intensity modulated radiotherapy (IMRT) versus conventional radiation on late xerostomia and Quality of Life aspects in head and neck cancer patients. Questionnaires on xerostomia in rest and during meals were sent to all patients treated between January 1999 and December 2003 with a T1-4, N0-2 M0 head and neck cancer, with parotid gland sparing IMRT or conventional bilateral neck irradiation to a dose of at least 60 Gy, who were progression free and had no disseminated disease (n = 192). Overall response was 85% (n = 163); 97% in the IMRT group (n = 75) and 77% in the control group (n = 88) the median follow-up was 2.6 years. The prevalence of complaints was compared between the two groups, correcting for all relevant factors at multivariate ordinal regression analysis. Patients treated with IMRT reported significantly less difficulty transporting and swallowing their food and needed less water for a dry mouth during day, night and meals. They also experienced fewer problems with speech and eating in public. Laryngeal cancer patients in general had fewer complaints than oropharynx cancer patients but both groups benefited from IMRT. Within the IMRT group the xerostomia scores were better for those patients with a mean parotid dose to the 'spared' parotid below 26 Gy. Parotid gland sparing IMRT for head and neck cancer patients improves xerostomia related quality of life compared to conventional radiation both in rest and during meals. Laryngeal cancer patients had fewer complaints but benefited equally compared to oropharyngeal cancer patients from IMRT

  3. Risk factors associated with xerostomia in haemodialysis patients.

    Science.gov (United States)

    López-Pintor, R-M; López-Pintor, L; Casañas, E; de Arriba, L; Hernández, G

    2017-03-01

    To determine the prevalence of xerostomia and hyposalivation in Haemodialysis (HD) patients, to clarify risk factors, assess patient's quality of life, and to establish a possible correlation among interdialytic weight gain (IDWG) and xerostomia. This study was performed on a group of 50 HD patients. Data were collected using a questionnaire containing demographic and clinical variables, a visual analogue scale (VAS) for xerostomia, IDWG, and an oral health impact profile questionnaire (OHIP-14). Unstimulated whole saliva (UWS) and stimulated whole saliva (SWS) were collected. A total of 28 HD patients (56%) suffered xerostomia. Dry mouth was associated with hypertension (OR, 5.24; 95% CI, 1.11-24.89) and benzodiazepine consumption (OR, 5.96; 95% CI, 1.05-33.99). The mean xerostomia VAS and OHIP-14 scores were 31.74±14.88 and 24.38±11.98, respectively. No significant correlation was observed between IDWG% and VAS and OHIP total score. Nonetheless, a positive correlation between VAS level of thirst and IDWG% was found (r=0.48 p=0.0001). UWS and SWS means (determined in 30 patients) were 0.16±0.17 and 1.12±0.64, respectively. Decreased values of UWS and SWS were reported in 53.33% and 36.66% of HD patients. Xerostomia in HD has a multifactorial aetiology due to accumulative risks as advanced age, systemic disorders, drugs, fluid intake restriction, and salivary parenchymal fibrosis and atrophy. Therefore, it is important to detect possible xerostomia risk factors to treat correctly dry mouth in HD patients and avoid systemic complications.

  4. Outcomes and xerostomia after postoperative radiotherapy for oral and oropharyngeal carcinoma.

    Science.gov (United States)

    Wang, Zhong-He; Yan, Chao; Zhang, Zhi-Yuan; Zhang, Chen-Ping; Hu, Hai-Sheng; Tu, Wen-Yong; Kirwan, Jessica; Mendenhall, William M

    2014-10-01

    We compared outcomes and xerostomia grade after postoperative intensity-modulated radiation therapy (IMRT) and conventional radiotherapy (RT) in patients with oral and oropharyngeal carcinoma. Eighty-eight patients with oral cavity (n = 77) and oropharyngeal (n = 11) carcinoma underwent postoperative IMRT (n = 44) or conventional RT (n = 44). Outcomes, failure patterns, volume, doses, salivary gland V30, and xerostomia grade were evaluated. The median follow-up was 53 months (range, 48-58 months). The median interval from surgery to RT was 4 weeks (range, 3-6 weeks). Twenty-one patients (7 and 14 for the IMRT and conventional RT groups, respectively) experienced local-regional failure. For the IMRT group, all 7 local-regional failures occurred in the high-dose target volumes. For the conventional RT group, there were 12 in-field failures, 1 at the margin, and 1 out-of-field. Nine patients experienced distant failure (5 and 4 for the IMRT and conventional RT groups, respectively). The 4-year local-regional control, disease-free survival (DFS), overall survival (OS), and distant-metastasis rates for the IMRT and conventional RT groups were 84.1% versus 68.2% (p = .055), 68.2% versus 52.3% (p = .091), 70.5% versus 56.8% (p = .124), and 11.4% versus 9.1% (p = .927), respectively. Xerostomia grade after RT was lower for IMRT compared to conventional RT (p xerostomia grade when compared to conventional RT. The predominant failure pattern was local. No differences were found in survival outcomes between both groups. There was a marginal difference in local-regional control. © 2014 Wiley Periodicals, Inc.

  5. Investigation of chemical vapour deposition diamond detectors by X-ray micro-beam induced current and X-ray micro-beam induced luminescence techniques

    International Nuclear Information System (INIS)

    Olivero, P.; Manfredotti, C.; Vittone, E.; Fizzotti, F.; Paolini, C.; Lo Giudice, A.; Barrett, R.; Tucoulou, R.

    2004-01-01

    Tracking detectors have become an important ingredient in high-energy physics experiments. In order to survive the harsh detection environment of the large hadron collider (LHC), trackers need to have special properties. They must be radiation hard, provide fast collection of charge, be as thin as possible and remove heat from readout electronics. The unique properties of diamond allow it to fulfill these requirements. In this work we present an investigation of the charge transport and luminescence properties of 'detector grade' artificial chemical vapour deposition (CVD) diamond devices developed within the CERN RD42 collaboration, performed by means of X-ray micro-beam induced current collection (XBICC) and X-ray micro-beam induced luminescence (XBIL) techniques. XBICC technique allows quantitative estimates of the transport parameters of the material to be evaluated and mapped with micrometric spatial resolution. In particular, the high resolution and sensitivity of the technique has allowed a quantitative study of the inhomogeneity of the charge transport parameter defined as the product of mobility and lifetime for both electron and holes. XBIL represents a technique complementary to ion beam induced luminescence (IBIL), which has already been used by our group, since X-ray energy loss profile in the material is different from that of MeV ions. X-ray induced luminescence maps have been performed simultaneously with induced photocurrent maps, to correlate charge transport and induced luminescence properties of diamond. Simultaneous XBICC and XBIL maps exhibit features of partial complementarity that have been interpreted on the basis of considerations on radiative and non-radiative recombination processes which compete with charge transport efficiency

  6. The effect of electron beam radiations on testicular damage in mice, Mus musculus

    International Nuclear Information System (INIS)

    Vikram, S.; Nair, Vijay Mala Grover

    2013-01-01

    Adult male Swiss albino mice, Mus musculus (8-10 weeks old) weighing 28±2.5 gm were exposed to varying doses (2-12 Gy) of electron beam radiations and maintained in animal house at 26-28 C. The animals were sacrificed following 35 and 60 days following exposure to electron beam radiations. The LD-50 value, change in the weight and histological details of the testis, sperm count, sperm shape abnormalities and sperm motility were recorded. The data suggests that electron beam radiations is a potential inducer to cause reproductive system dysfunctions which probably may be responsible leading to infertility. (author)

  7. Prevalence of xerostomia in patients attending Shorish dental speciality in Sulaimani city

    Science.gov (United States)

    2015-01-01

    Objectives: The aim of this study was to investigate the prevalence of xerostomia among dental patients and explore the possible risk factors and symptoms associated with this condition. Patient and Methods: The prevalence of xerostomia and its associations were investigated among patients (n=1132) who were visiting the department of oral medicine at shorish dental speciality in sulaimani city. The age range was between 10-79 years. 512 (45.2%) of participants were males and 620 (54.8%) were females. The data collected were age, sex, systemic diseases, medications and habit of smoking. Logistic regression models to estimate odds ratios and 95% confidence intervals were used to investigate the association of xerostomia with age, systemic diseases and medications and Chi Square test was also used to analyze the data. Results: Prevalence of xerostomia was 16.07%. Prevalence of xerostomia was significantly higher among females (19.51%) than males (11.91%) (P=0.001). The most common diseases with the highest prevalence of xerostomia were psychological disorders (57.14%) followed by diabetes mellitus (53.84%), neurological disorders (40%), thyroid disorders (37.5%) and hypertension (36.48%). The most common medication with the highest prevalence of xerostomia was antihistamine (66.66%) followed by psychotherapeutic medications (60%), pain medications (55.88%), endocrinologic agents (51.21%), antidyslipidic agents (50%) and antihypertensive medication (38.98%). Xerostomia was significantly associated with ageing (OR: 1.02, P=0.000), systemic diseases (OR: 2.80, P=0.000) and medications (OR: 5.17, P=0.000). There was a high prevalence of reported symptoms of xerostomia and these symptoms were more prevalent among females, Prevalence of xerostomia was higher in heavy smoker patients (19.48%) than non smoker patients but not significantly (16.14%) (p= 0.44). Conclusions: There was a high prevalence of xerostomia among dental patients; xerostomia was significantly more

  8. Xerostomia relates to the degree of asthma control.

    Science.gov (United States)

    Alcázar Navarrete, Bernardino; Gómez-Moreno, Gerardo; Aguilar-Salvatierra, Antonio; Guardia, Javier; Romero Palacios, Pedro José

    2015-04-01

    Few studies have assessed the relationships between xerostomia and the use of inhaled corticosteroids (ICS). The main objective of this study was to investigate the prevalence of xerostomia in a respiratory outpatient clinic and its relationship with bronchial asthma and ICS use. A cross-sectional observational study of patients recruited in an outpatient setting divided them according to previous diagnoses of bronchial asthma. Data about pulmonary function, concomitant medication, medical comorbidities, Xerostomia Inventory test (XI test), and the degree of asthma control by ACT (asthma control test) were collected for each patient. A linear regression model was applied, using the XI score as dependent variable and the ACT score as independent variable. The 57 patients were divided into asthmatics (40 patients, 70.2%) and control group without asthma (17, 29.8%). The prevalence of xerostomia was 87.7% (50 patients), with no differences between the study groups or current dose of ICS. In the asthmatic group, patients with uncontrolled asthma had worse XI scores than those with partially or totally controlled asthma (30.43 ± 8.71 vs. 24.92 ± 8.08; P Xerostomia is a common symptom in the ambulatory setting. There is a moderate relationship between the degree of asthma control and the severity of xerostomia. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  9. Xerostomia, Hyposalivation, and Salivary Flow in Diabetes Patients

    OpenAIRE

    L?pez-Pintor, Rosa Mar?a; Casa?as, Elisabeth; Gonz?lez-Serrano, Jos?; Serrano, Julia; Ram?rez, Luc?a; de Arriba, Lorenzo; Hern?ndez, Gonzalo

    2016-01-01

    The presence of xerostomia and hyposalivation is frequent among diabetes mellitus (DM) patients. It is not clear if the presence of xerostomia and hyposalivation is greater in DM than non-DM patients. The aims of this systematic review are (1) to compare the prevalence rates of xerostomia, (2) to evaluate the salivary flow rate, and (3) to compare the prevalence rates of hyposalivation in DM versus non-DM population. This systematic review was conducted according to the PRISMA group guideline...

  10. Parotid gland sparing IMRT for head and neck cancer improves xerostomia related quality of life

    Science.gov (United States)

    van Rij, CM; Oughlane-Heemsbergen, WD; Ackerstaff, AH; Lamers, EA; Balm, AJM; Rasch, CRN

    2008-01-01

    Background and purpose To assess the impact of intensity modulated radiotherapy (IMRT) versus conventional radiation on late xerostomia and Quality of Life aspects in head and neck cancer patients. Patients and nethods Questionnaires on xerostomia in rest and during meals were sent to all patients treated between January 1999 and December 2003 with a T1-4, N0-2 M0 head and neck cancer, with parotid gland sparing IMRT or conventional bilateral neck irradiation to a dose of at least 60 Gy, who were progression free and had no disseminated disease (n = 192). Overall response was 85% (n = 163); 97% in the IMRT group (n = 75) and 77% in the control group (n = 88) the median follow-up was 2.6 years. The prevalence of complaints was compared between the two groups, correcting for all relevant factors at multivariate ordinal regression analysis. Results Patients treated with IMRT reported significantly less difficulty transporting and swallowing their food and needed less water for a dry mouth during day, night and meals. They also experienced fewer problems with speech and eating in public. Laryngeal cancer patients in general had fewer complaints than oropharynx cancer patients but both groups benefited from IMRT. Within the IMRT group the xerostomia scores were better for those patients with a mean parotid dose to the "spared" parotid below 26 Gy. Conclusion Parotid gland sparing IMRT for head and neck cancer patients improves xerostomia related quality of life compared to conventional radiation both in rest and during meals. Laryngeal cancer patients had fewer complaints but benefited equally compared to oropharyngeal cancer patients from IMRT. PMID:19068126

  11. Parotid gland sparing IMRT for head and neck cancer improves xerostomia related quality of life

    Directory of Open Access Journals (Sweden)

    Balm AJM

    2008-12-01

    Full Text Available Abstract Background and purpose To assess the impact of intensity modulated radiotherapy (IMRT versus conventional radiation on late xerostomia and Quality of Life aspects in head and neck cancer patients. Patients and nethods Questionnaires on xerostomia in rest and during meals were sent to all patients treated between January 1999 and December 2003 with a T1-4, N0-2 M0 head and neck cancer, with parotid gland sparing IMRT or conventional bilateral neck irradiation to a dose of at least 60 Gy, who were progression free and had no disseminated disease (n = 192. Overall response was 85% (n = 163; 97% in the IMRT group (n = 75 and 77% in the control group (n = 88 the median follow-up was 2.6 years. The prevalence of complaints was compared between the two groups, correcting for all relevant factors at multivariate ordinal regression analysis. Results Patients treated with IMRT reported significantly less difficulty transporting and swallowing their food and needed less water for a dry mouth during day, night and meals. They also experienced fewer problems with speech and eating in public. Laryngeal cancer patients in general had fewer complaints than oropharynx cancer patients but both groups benefited from IMRT. Within the IMRT group the xerostomia scores were better for those patients with a mean parotid dose to the "spared" parotid below 26 Gy. Conclusion Parotid gland sparing IMRT for head and neck cancer patients improves xerostomia related quality of life compared to conventional radiation both in rest and during meals. Laryngeal cancer patients had fewer complaints but benefited equally compared to oropharyngeal cancer patients from IMRT.

  12. Importance of the initial volume of parotid glands in xerostomia for patients with head and neck cancers treated with IMRT

    International Nuclear Information System (INIS)

    Nishimura, Yasumasa; Nakamatsu, Kiyoshi; Shibata, Toru; Kanamori, Shuichi; Koike, Ryuta; Okumura, Masahiko; Suzuki, Minoru

    2005-01-01

    Our aim was to evaluate predictors of xerostomia in patients with head and neck cancers treated with intensity-modulated radiation therapy (IMRT). Thirty-three patients with pharyngeal cancer were evaluated for xerostomia after having been treated with IMRT. All patients were treated with whole-neck irradiation of 46-50 Gy by IMRT, followed by boost IMRT to the high-risk clinical target volume to a total dose of 56-70 Gy in 28-35 fractions (median, 68 Gy). For boost IMRT, a second computed tomography (CT-2) scan was done in the third to fourth week of IMRT. Xerostomia was scored 3-4 months after the start of IMRT. The mean doses to the contralateral and ipsilateral parotid glands were 24.0±6.2 and 30.3±6.6 Gy, respectively. Among the 33 patients, xerostomia of grades 0, 1, 2 and 3 was noted in one, 18, 12 and two patients, respectively. Although the mean dose to the parotid glands was not correlated with the grade of xerostomia, the initial volume of the parotid glands was correlated with the grade of xerostomia (P=0.04). Of 17 patients with small parotid glands (≤38.8 ml) on initial CT (CT-1), 11 (65%) showed grade 2 or grade 3 xerostomia, whereas only three (19%) of 16 patients with larger parotid glands showed grade 2 xerostomia (P<0.05). The mean volume of the parotid glands on CT-1 was 43.1±15.2 ml, but decreased significantly to 32.0±11.4 ml (74%) on CT-2 (P<0.0001). Initial volumes of the parotid glands are significantly correlated with the grade of xerostomia in patients treated with IMRT. The volume of the parotid glands decreased significantly during the course of IMRT. (author)

  13. Dry Mouth (Xerostomia)

    Science.gov (United States)

    ... Finding Dental Care Home Health Info Health Topics Dry Mouth Saliva, or spit, is made by the salivary ... help keep teeth strong and fight tooth decay. Dry mouth, also called xerostomia (ZEER-oh-STOH-mee-ah), ...

  14. Electromagnetic radiation from beam-plasma instabilities

    International Nuclear Information System (INIS)

    Stenzel, R.L.; Whelan, D.A.

    1982-01-01

    This chapter investigates the mechanism by which unstable electrostatic waves of an electron-beam plasma system are converted into observed electromagnetic waves. Electromagnetic radiation arises from both natural beam-plasma systems (e.g., type III solar bursts and kilometric radiation), and from man-made electron beams injected from rockets and spacecraft. A pulsed magnetized discharge plasma is produced with a 1 m diam. oxide-coated cathode and the discussed experiment is performed in the quiescent afterglow. The primary beam-plasma instability involves the excitation of electrostatic plasma waves. Electromagnetic radiation from the beam-plasma system is observed with microwave antennas outside the plasma (all probes removed) or with coax-fed dipoles which can be inserted radially and axially into the plasma. The physical process of mode coupling by which electromagnetic radiation is generated in an electrostatic beam-plasma instability is identified. The results are relevant to beam injection experiments from rockets or satellites into space plasmas. The limited penetration of the beam current into the plasma due to instabilities is demonstrated

  15. Intensity-Modulated Radiotherapy Reduces Radiation-Induced Morbidity and Improves Health-Related Quality of Life: Results of a Nonrandomized Prospective Study Using a Standardized Follow-Up Program

    International Nuclear Information System (INIS)

    Vergeer, Marije R.; Doornaert, Patricia A.H.; Rietveld, Derek H.F.; Leemans, C. Rene; Slotman, Ben J.; Langendijk, Johannes A.

    2009-01-01

    Purpose: The purpose of this study was to compare intensity-modulated radiation therapy (IMRT) and three-dimensional conventional radiotherapy (3D-CRT) with regard to patient-rated xerostomia, Radiation Therapy Oncology Group (RTOG) acute and late xerostomia and health-related quality of life (HRQoL) among patients with head and neck squamous cell carcinoma (HNSCC). Methods and Materials: Included were 241 patients with HNSCC treated with bilateral irradiation ± chemotherapy. Since 2000, all patients treated with HNSCC were included in a program, which prospectively assessed acute and late morbidity according to the RTOG and HRQoL on a routine basis at regular intervals. Before October 2004, all patients were treated with 3D-CRT (N = 150). After clinical implementation in October 2004, 91 patients received IMRT. In this study, the differences regarding RTOG toxicity, xerostomia, and other items of HRQoL were analyzed. Results: The use of IMRT resulted in a significant reduction of the mean dose of the parotid glands (27 Gy vs. 43 Gy (p < 0.001). During radiation, Grade 2 RTOG xerostomia was significantly less with IMRT than with 3D-CRT. At 6 months, the prevalence of patient-rated moderate to severe xerostomia and Grade 2 or higher RTOG xerostomia was significantly lower after IMRT versus 3D-CRT. Treatment with IMRT also had a positive effect on several general and head and neck cancer-specific HRQoL dimensions. Conclusions: IMRT results in a significant reduction of patient- and observer-rated xerostomia, as well as other head and neck symptoms, compared with standard 3D-CRT. These differences translate into a significant improvement of the more general dimensions of HRQoL.

  16. Electromagnetic radiation from beam-plasma instabilities

    Science.gov (United States)

    Pritchett, P. L.; Dawson, J. M.

    1983-01-01

    A computer simulation is developed for the generation of electromagnetic radiation in an electron beam-plasma interaction. The plasma is treated as a two-dimensional finite system, and effects of a continuous nonrelativistic beam input are accounted for. Three momentum and three field components are included in the simulation, and an external magnetic field is excluded. EM radiation generation is possible through interaction among Langmuir oscillations, ion-acoustic waves, and the electromagnetic wave, producing radiation perpendicular to the beam. The radiation is located near the plasma frequency, and polarized with the E component parallel to the beam. The scattering of Langmuir waves caused by ion-acoustic fluctuations generates the radiation. Comparison with laboratory data for the three-wave interactions shows good agreement in terms of the radiation levels produced, which are small relative to the plasma thermal energy.

  17. Protective effect of Asparagus racemosus root extract against lethal total - body electron beam radiation induced damage in Swiss albino mice

    International Nuclear Information System (INIS)

    Sharmila, K.P.; Bhandary, B. Satheesh Kumar; Suchetha Kumari, N.; Bhat, Vadish S.; Shetty, Jayaram; Peter, Alex John; Jose, Jerish M.; Fernandes, Ronald

    2016-01-01

    To investigate the protective effect of Asparagus Racemosus Root ethanolic extract (ARE) in Swiss albino mice against acute lethal total - body Electron beam irradiation. Swiss Albino mice were used for the assessment of radiation induced sickness and 30 day survival analysis. Survival studies were determined using the Kaplan-Meier survival curves. The maximum survival was observed in the experimental mice pretreated with 200 mg/kg.b.wt. of ARE which also reduced the radiation sickness characteristics. This dose was considered as an optimal dose for radioprotection. Treatment of mice with ARE before irradiation delayed the onset of mortality as compared with the untreated irradiated controls. Present findings demonstrate the potential of ARE in mitigating radiation-induced mortality, which may be attributed to its free radical scavenging and increased antioxidant potential

  18. Internet information on xerostomia : what should patients expect?

    NARCIS (Netherlands)

    Delli, K.; Livas, C.; Spijkervet, F. K.; Vissink, A.

    ObjectiveTo assess the qualitative standards of the information distributed via the Internet regarding xerostomia. Materials and MethodsA comprehensive electronic search was performed for xerostomia' and dry mouth' separately using four search engines. The first 30 results from each search

  19. A risk prediction model for xerostomia: a retrospective cohort study.

    Science.gov (United States)

    Villa, Alessandro; Nordio, Francesco; Gohel, Anita

    2016-12-01

    We investigated the prevalence of xerostomia in dental patients and built a xerostomia risk prediction model by incorporating a wide range of risk factors. Socio-demographic data, past medical history, self-reported dry mouth and related symptoms were collected retrospectively from January 2010 to September 2013 for all new dental patients. A logistic regression framework was used to build a risk prediction model for xerostomia. External validation was performed using an independent data set to test the prediction power. A total of 12 682 patients were included in this analysis (54.3%, females). Xerostomia was reported by 12.2% of patients. The proportion of people reporting xerostomia was higher among those who were taking more medications (OR = 1.11, 95% CI = 1.08-1.13) or recreational drug users (OR = 1.4, 95% CI = 1.1-1.9). Rheumatic diseases (OR = 2.17, 95% CI = 1.88-2.51), psychiatric diseases (OR = 2.34, 95% CI = 2.05-2.68), eating disorders (OR = 2.28, 95% CI = 1.55-3.36) and radiotherapy (OR = 2.00, 95% CI = 1.43-2.80) were good predictors of xerostomia. For the test model performance, the ROC-AUC was 0.816 and in the external validation sample, the ROC-AUC was 0.799. The xerostomia risk prediction model had high accuracy and discriminated between high- and low-risk individuals. Clinicians could use this model to identify the classes of medications and systemic diseases associated with xerostomia. © 2015 John Wiley & Sons A/S and The Gerodontology Association. Published by John Wiley & Sons Ltd.

  20. Laser induced focusing for over-dense plasma beams

    International Nuclear Information System (INIS)

    Schmidt, Peter; Boine-Frankenheim, Oliver; Mulser, Peter

    2015-01-01

    The capability of ion acceleration with high power, pulsed lasers has become an active field of research in the past years. In this context, the radiation pressure acceleration (RPA) mechanism has been the topic of numerous theoretical and experimental publications. Within that mechanism, a high power, pulsed laser beam hits a thin film target. In contrast to the target normal sheath acceleration, the entire film target is accelerated as a bulk by the radiation pressure of the laser. Simulations predict heavy ion beams with kinetic energy up to GeV, as well as solid body densities. However, there are several effects which limit the efficiency of the RPA: On the one hand, the Rayleigh-Taylor-instability limits the predicted density. On the other hand, conventional accelerator elements, such as magnetic focusing devices are too bulky to be installed right after the target. Therefore, we present a new beam transport method, suitable for RPA-like/over-dense plasma beams: laser induced focusing

  1. Xerostomia of Various Etiologies: A Review of the Literature.

    Science.gov (United States)

    Tanasiewicz, Marta; Hildebrandt, Tomasz; Obersztyn, Izabela

    2016-01-01

    This paper presents the etiopathogenesis, symptomatology, evaluation and treatment of mouth dryness. Xerostomia affects 1-29% of the population, mostly women. It is observed in geriatric patients and in individuals using certain medications, those subjected to radiotherapy of the head and neck region or affected with autoimmune conditions. The main signs of xerostomia include the impression of a dry mouth, problems with food ingestion and dryness of the oral mucosa and skin. Evaluation is based on structured interviews (the Fox test) and determinations of unstimulated and stimulated salivary volume. The signs of xerostomia can be attenuated with saliva substitutes, cevimeline or malic acid. Only palliative treatment of this condition is available at present. Untreated xerostomia significantly impairs the quality of life, which can potentially lead to depression.

  2. External Beam Radiation Therapy for Cancer

    Science.gov (United States)

    External beam radiation therapy is used to treat many types of cancer. it is a local treatment, where a machine aims radiation at your cancer. Learn more about different types of external beam radiation therapy, and what to expect if you're receiving treatment.

  3. Xerostomia Among Older Adults With Low Income: Nuisance or Warning?

    Science.gov (United States)

    Lee, Young-Shin; Kim, Hee-Gerl; Moreno, Kim

    2016-01-01

    The purpose of this study was to identify the prevalence of xerostomia and related factors among low-income older adults in South Korea. A cross-sectional, population-based study. Using data from the Home Healthcare Service Project, a population-based interview survey with home healthcare service, a total of 9,840 adults 65 years of age and older were assessed for the presence of xerostomia in association with aspects of health lifestyles, chronic disease, oral conditions, and oral function. Overall, 40% of participants reported experiencing xerostomia. Multivariate regression analysis indicated xerostomia was more likely to be reported by women having symptoms of gingival bleeding/pain, having difficulty swallowing liquid or chewing solid food, and having multiple chronic diseases. Interestingly, older adults who live alone and drink alcohol (two or more times per week) reported fewer problems with xerostomia. Increased focus on the detrimental health consequences of xerostomia would make treatment a higher priority. Improved assessment of at-risk populations, particularly among the elderly, could lead to earlier preventative interventions, lessening the negative impact on quality of life. Health professionals along with the general public need increased knowledge about the detrimental effects of xerostomia on overall health. There is a need for earlier assessment and treatment to facilitate optimal health promotion and disease prevention. © 2015 Sigma Theta Tau International.

  4. TAT-Mediated Delivery of Tousled Protein to Salivary Glands Protects Against Radiation-Induced Hypofunction

    Energy Technology Data Exchange (ETDEWEB)

    Sunavala-Dossabhoy, Gulshan, E-mail: gsunav@lsuhsc.edu [Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, LA (United States); Palaniyandi, Senthilnathan; Richardson, Charles; De Benedetti, Arrigo [Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, LA (United States); Schrott, Lisa [Department of Pharmacology, Toxicology, and Neuroscience, Louisiana State University Health Sciences Center, Shreveport, LA (United States); Caldito, Gloria [Department of Bioinformatics and Computational Biology, Louisiana State University Health Sciences Center, Shreveport, LA (United States)

    2012-09-01

    Purpose: Patients treated with radiotherapy for head-and-neck cancer invariably suffer its deleterious side effect, xerostomia. Salivary hypofunction ensuing from the irreversible destruction of glands is the most common and debilitating oral complication affecting patients undergoing regional radiotherapy. Given that the current management of xerostomia is palliative and ineffective, efforts are now directed toward preventive measures to preserve gland function. The human homolog of Tousled protein, TLK1B, facilitates chromatin remodeling at DNA repair sites and improves cell survival against ionizing radiation (IR). Therefore, we wanted to determine whether a direct transfer of TLK1B protein to rat salivary glands could protect against IR-induced salivary hypofunction. Methods: The cell-permeable TAT-TLK1B fusion protein was generated. Rat acinar cell line and rat salivary glands were pretreated with TAT peptide or TAT-TLK1B before IR. The acinar cell survival in vitro and salivary function in vivo were assessed after radiation. Results: We demonstrated that rat acinar cells transduced with TAT-TLK1B were more resistant to radiation (D{sub 0} = 4.13 {+-} 1.0 Gy; {alpha}/{beta} = 0 Gy) compared with cells transduced with the TAT peptide (D{sub 0} = 4.91 {+-} 1.0 Gy; {alpha}/{beta} = 20.2 Gy). Correspondingly, retroductal instillation of TAT-TLK1B in rat submandibular glands better preserved salivary flow after IR (89%) compared with animals pretreated with Opti-MEM or TAT peptide (31% and 39%, respectively; p < 0.01). Conclusions: The results demonstrate that a direct transfer of TLK1B protein to the salivary glands effectively attenuates radiation-mediated gland dysfunction. Prophylactic TLK1B-protein therapy could benefit patients undergoing radiotherapy for head-and-neck cancer.

  5. Oral toxicity management in head and neck cancer patients treated with chemotherapy and radiation: Xerostomia and trismus (Part 2). Literature review and consensus statement.

    Science.gov (United States)

    Buglione, Michela; Cavagnini, Roberta; Di Rosario, Federico; Maddalo, Marta; Vassalli, Lucia; Grisanti, Salvatore; Salgarello, Stefano; Orlandi, Ester; Bossi, Paolo; Majorana, Alessandra; Gastaldi, Giorgio; Berruti, Alfredo; Trippa, Fabio; Nicolai, Pietro; Barasch, Andrei; Russi, Elvio G; Raber-Durlacher, Judith; Murphy, Barbara; Magrini, Stefano M

    2016-06-01

    Radiotherapy alone or in combination with chemotherapy and/or surgery is a well-known radical treatment for head and neck cancer patients. Nevertheless acute side effects (such as moist desquamation, skin erythema, loss of taste, mucositis etc.) and in particular late toxicities (osteoradionecrosis, xerostomia, trismus, radiation caries etc.) are often debilitating and underestimated. A multidisciplinary group of head and neck cancer specialists from Italy met in Milan with the aim of reaching a consensus on a clinical definition and management of these toxicities. The Delphi Appropriateness method was used for this consensus and external experts evaluated the conclusions. The paper contains 20 clusters of statements about the clinical definition and management of stomatological issues that reached consensus, and offers a review of the literature about these topics. The review was split into two parts: the first part dealt with dental pathologies and osteo-radionecrosis (10 clusters of statements), whereas this second part deals with trismus and xerostomia (10 clusters of statements). Copyright © 2016. Published by Elsevier Ireland Ltd.

  6. Xerostomia: A day and night difference

    International Nuclear Information System (INIS)

    Dijkema, Tim; Raaijmakers, Cornelis P.J.; Braam, Pètra M.; Roesink, Judith M.; Monninkhof, Evelyn M.; Terhaard, Chris H.J.

    2012-01-01

    Purpose: To compare patient-reported xerostomia during daytime and during nighttime with objectively measured parotid and submandibular gland function in a cohort of head-and-neck cancer (HNC) patients treated with RT. Materials and methods: A cohort of 138 HNC patients underwent objective measurements of parotid (PF) and submandibular (SMF) gland function and completed a xerostomia questionnaire (XQ) before RT, at 6 weeks, 6 months and 1 year after RT. No attempt was made to spare the submandibular gland(s). The XQ contained specific questions concerning the sensation of dry mouth during day- (XD) and nighttime (XN), scored on a 5-point Likert scale. Patients with no or mild (grade 1–3) xerostomia and patients with more severe (grade 4–5) complaints were grouped together. Results: Before RT, no association existed between dry mouth complaints and PF or SMF. At 6 weeks, 6 months and 1 year after RT; 37%, 51% and 36% had grade 4–5 XD and 65%, 64% and 56% had grade 4–5 XN, respectively. Patients with grade 4–5 XD and XN had significantly worse SMF at all time points after RT compared to patients with grade 1–3 XD and XN, while PF was significantly worse only at 6 weeks after RT. In multivariate analyses, SMF was consistently the most important factor related to XN after treatment. PF significantly influenced XD at 6 weeks and 1 year after RT. Conclusions: Differentiating between complaints during day- and nighttime in xerostomia research is necessary. Dry mouth at night is a frequent problem after (parotid-sparing) RT for HNC and is explained by submandibular gland dysfunction. Sparing of the contralateral submandibular gland, in addition to parotid gland sparing, may result in improved patient-reported xerostomia.

  7. Can sparing of the superficial contralateral parotid lobe reduce xerostomia following radiotherapy for head and neck cancer?

    Science.gov (United States)

    Nevens, Daan; Nuyts, Sandra

    2017-12-01

    The purpose of this study is to see whether sparing the superficial contralateral parotid lobe can help limiting xerostomia following radiotherapy for head and neck cancer. 88 patients that were included in two prospective randomized studies were analysed in the current study. Using the dosimetry of both the parotid glands, we divided our patients in four groups. Group 1 includes patients where we were able to reduce the radiation dose below the threshold in order to spare both the ipsilateral and contralateral parotid glands, Group 2 consists of patients where only the contralateral parotid gland could be spared. Group 3 consists of patients where only the contralateral superficial parotid lobe could be spared, while in Group 4 not even the contralateral superficial lobe could be spared. When we compared Group 1 and Group 2, we did not observe a significant difference between both groups in terms of xerostomia scores at 6 or 12 months. When we compared these groups with Group 3, we observed significant differences with more xerostomia in Group 3 where only the contralateral superficial lobe was spared. A significant difference was also observed between Group 3 and Group 4 with more xerostomia in Group 4. Sparing of just one superficial parotid lobe results in less xerostomia when compared to not sparing any lobe of both parotid glands. Advances in knowledge: When sparing of the whole contralateral parotid gland is not possible, delineating both the superficial parotid glands and trying to spare at least one of them can mean a way forward in limiting xerostomia in head and neck cancer patients treated with radiotherapy.

  8. Salivary Gland Dysfunction and Xerostomia in Sjogren's Syndrome

    NARCIS (Netherlands)

    Jensen, Siri Beier; Vissink, Arjan

    In this article, salivary gland dysfunction and xerostomia in Sjogren's syndrome (SS) are discussed, with a focus on the pathophysiology of salivary dysfunction in SS, the clinical presentation of dry mouth in SS, how to assess salivary gland hypofunction and xerostomia in SS, and the impact of

  9. Role of lutein in alleviating the effects of electron beam radiation induced hematological and biochemical changes in Swiss albino mice

    International Nuclear Information System (INIS)

    Vidya, V.; Krishna, A.P.; Patil, Shrikant; Fernandes, Ronald

    2016-01-01

    Lutein is a naturally occurring xanthophyll pigment derived from α-carotene. It is abundantly present in Tagetes erecta L. (marigold) and also present in a few vegetables, fruits and in animal sources. Lutein was evaluated for its protective role in electron beam radiation induced damages in Swiss albino mice. The drug was optimized for its radioprotective activity

  10. Chromosome aberrations induced by 135 MeV of carbon and neon beams by PRC

    International Nuclear Information System (INIS)

    Ohara, Hiroshi; Minamihisamatu, Masako; Kanai, Tatsuaki; Eguchi-Kasai, Kiyomi; Itsukaichi, Hiromi; Fukutsu, Kumiko; Yatagai, Fumio; Sato, Kohki.

    1993-01-01

    Radiation-induced chromosome aberration can be an indicator of the radiation lesions in irradiated cells. Many studies on chromosome aberration induced by X-ray and γ - ray have indicated that the dose response of the aberration can be fitted to a quadratic equation, Y = αD + βD 2 , and it becomes linear as the LET of beams increases. The main subject of this study was some quantification of chromosomal aberration induced by 135 MeV/n carbon and neon beams produced by the RRC, the operation of which increasingly became useful for the studies on heavy ion biology. The results will meet with some of the radiobiological features connected to the specific action of charged particles. The materials used, the experimental method and the results are reported. Four curves of the dose response for the production of dicentric and ring types of aberration induced by carbon and neon beams and four different dose average LETs are given. Aberration production rate became higher as LET increased. Chromosome aberration can be quantified as an indicator of radiation lesions in the case of high LET particle radiation. (K.I.)

  11. Polymer electrolyte membranes for fuel cells by radiation induced grafting with electron beam irradiation: state-of-the-art

    International Nuclear Information System (INIS)

    Nasef, M.M.; Nasef, M.M.

    2010-01-01

    Polymer electrolyte membranes have generated considerable interest in various fields of industrial interest due to their wide spread applications in fuel cells, batteries, electrolyzers sensors and actuators. Such diversity in applications implies a strong demand to architect the membranes towards particular properties for specific applications. Radiation induced grafting of vinyl and acrylic monomers into polymeric films, is an appealing method for producing various polymer electrolyte membranes. This method has the advantages of simplicity, controllability over the composition leading to tailored membrane properties and absence of shaping problem as preparation starts with substrate in a film form. It also has the flexibility of using various types of radiation sources such as gamma-rays and electron beam. Of all, electron beam (EB) accelerator is an advantageous source of high energy radiation that can initiate grafting reactions required for preparation of the membranes particularly when pilot scale production and commercial applications are sought. The grafting penetration can be varied from surface to bulk of membranes depending on the acceleration energy. This lecture reviews the-state of- the-art in the use of EB irradiation in preparation of composite and grafted polymer electrolyte membranes for fuel cell applications by radiation induced grafting with simultaneous irradiation and preirradiation methods. The use of simultaneous EB irradiation method was found to simplify the process and reduce the reaction time as well as the monomer consumption whereas the use of preirradiation method in a single-step route provides a shorter route to prepare polymer electrolyte membranes with improved properties and reduced cost in addition of setting basis for designing a continuous line to produce these membranes with dedicated EB facilities

  12. Photoluminescence of radiation-induced color centers in lithium fluoride thin films for advanced diagnostics of proton beams

    Science.gov (United States)

    Piccinini, M.; Ambrosini, F.; Ampollini, A.; Picardi, L.; Ronsivalle, C.; Bonfigli, F.; Libera, S.; Nichelatti, E.; Vincenti, M. A.; Montereali, R. M.

    2015-06-01

    Systematic irradiation of thermally evaporated 0.8 μm thick polycrystalline lithium fluoride films on glass was performed by proton beams of 3 and 7 MeV energies, produced by a linear accelerator, in a fluence range from 1011 to 1015 protons/cm2. The visible photoluminescence spectra of radiation-induced F2 and F3+ laser active color centers, which possess almost overlapping absorption bands at about 450 nm, were measured under laser pumping at 458 nm. On the basis of simulations of the linear energy transfer with proton penetration depth in LiF, it was possible to obtain the behavior of the measured integrated photoluminescence intensity of proton irradiated LiF films as a function of the deposited dose. The photoluminescence signal is linearly dependent on the deposited dose in the interval from 103 to about 106 Gy, independently from the used proton energies. This behavior is very encouraging for the development of advanced solid state radiation detectors based on optically transparent LiF thin films for proton beam diagnostics and two-dimensional dose mapping.

  13. Herbal Medicine for Xerostomia in Cancer Patients: A Systematic Review of Randomized Controlled Trials.

    Science.gov (United States)

    Park, Bongki; Noh, Hyeonseok; Choi, Dong-Jun

    2018-06-01

    Xerostomia (dry mouth) causes many clinical problems, including oral infections, speech difficulties, and impaired chewing and swallowing of food. Many cancer patients have complained of xerostomia induced by cancer therapy. The aim of this systematic review is to assess the efficacy of herbal medicine for the treatment of xerostomia in cancer patients. Randomized controlled trials investigating the use of herbal medicines to treat xerostomia in cancer patients were included. We searched the following 12 databases without restrictions on time or language. The risk of bias was assessed using the Cochrane Risk of Bias Tool. Twenty-five randomized controlled trials involving 1586 patients met the inclusion criteria. A total of 24 formulas were examined in the included trials. Most of the included trials were insufficiently reported in the methodology section. Five formulas were shown to significantly improve the salivary flow rate compared to comparators. Regarding the grade of xerostomia, all formulas with the exception of a Dark Plum gargle solution with normal saline were significantly effective in reducing the severity of dry mouth. Adverse events were reported in 4 trials, and adverse effects of herbal medicine were reported in 3 trials. We found herbal medicines had potential benefits for improving salivary function and reducing the severity of dry mouth in cancer patients. However, methodological limitations and a relatively small sample size reduced the strength of the evidence. More high-quality trials reporting sufficient methodological data are warranted to enforce the strength of evidence regarding the effectiveness of herbal medicines.

  14. Restoration of radiation therapy-induced salivary gland dysfunction in mice by post therapy IGF-1 administration

    International Nuclear Information System (INIS)

    Grundmann, Oliver; Fillinger, Jamia L; Victory, Kerton R; Burd, Randy; Limesand, Kirsten H

    2010-01-01

    Radiotherapy for head and neck cancer results in severe and chronic salivary gland dysfunction in most individuals. This results in significant side effects including xerostomia, dysphagia, and malnutrition which are linked to significant reductions in patients' quality of life. Currently there are few xerostomia treatment approaches that provide long-term results without significant side effects. To address this problem we investigated the potential for post-therapeutic IGF-1 to reverse radiation-induced salivary gland dysfunction. FVB mice were treated with targeted head and neck radiation and significant reductions in salivary function were confirmed 3 days after treatment. On days 4-8 after radiation, one group of mice was injected intravenously with IGF-1 while a second group served as a vehicle control. Stimulated salivary flow rates were evaluated on days 30, 60, and 90 and histological analysis was performed on days 9, 30, 60, and 90. Irradiated animals receiving vehicle injections have 40-50% reductions in stimulated salivary flow rates throughout the entire time course. Mice receiving injections of IGF-1 have improved stimulated salivary flow rates 30 days after treatment. By days 60-90, IGF-1 injected mice have restored salivary flow rates to unirradiated control mice levels. Parotid tissue sections were stained for amylase as an indicator of functioning acinar cells and significant reductions in total amylase area are detected in irradiated animals compared to unirradiated groups on all days. Post-therapeutic injections of IGF-1 results in increased amylase-positive acinar cell area and improved amylase secretion. Irradiated mice receiving IGF-1 show similar proliferation indices as untreated mice suggesting a return to tissue homeostasis. Post-therapeutic IGF-1 treatment restores salivary gland function potentially through normalization of cell proliferation and improved expression of amylase. These findings could aid in the rational design of

  15. Effect of Xerostomia on the Functional Capacity of Subjects with Rheumatoid Arthritis.

    Science.gov (United States)

    Lins E Silva, Marília; Carvalho, Camila Nunes; Carvalho, Alessandra de Albuquerque Tavares; Leão, Jair Carneiro; Duarte, Angela Luzia Pinto; Gueiros, Luiz Alcino

    2016-10-01

    To evaluate the intensity of xerostomia and hyposalivation in subjects with rheumatoid arthritis (RA) as well as the effects of these conditions on functional incapacity and disease activity. The study sample comprised 236 individuals of both sexes who had RA. All the individuals were submitted to clinical evaluation and unstimulated sialometry. Functional capacity was determined by using the Health Assessment Questionnaire (HAQ), xerostomia was assessed using the Xerostomia Inventory, and disease activity was evaluated with the 28-joint Disease Activity Score (DAS28). The effect of Sjögren syndrome (SS) was analyzed, and the sample was divided into 2 groups: RA (191 subjects) and RA/SS (45 subjects). The Xerostomia Inventory showed positive and significant correlation with fatigue (r = 0.243; p xerostomia (OR 3.89, 95% CI 1.84-8.23, p Xerostomia demonstrated an adverse effect on quality of life of subjects with RA, being associated with a reduction in functional capacity. In this clinical setting, xerostomia can be monitored as a marker of worse clinical evolution.

  16. Xerostomia after radiotherapy in the head and neck area: Long-term observations

    International Nuclear Information System (INIS)

    Messmer, Marc-Benjamin; Thomsen, Andreas; Kirste, Simon; Becker, Gerhild; Momm, Felix

    2011-01-01

    To investigate the development of xerostomia more than 5 years after radiotherapy for head and neck cancer, a prospective longitudinal study was done. A xerostomia questionnaire was answered by 42 patients 41 and 90 months after radiotherapy: xerostomia at rest did not change significantly over time whereas the difficulties with speaking improved and the difficulties with eating worsened. Subjective xerostomia does not reach a steady state even more than 5 years after radiotherapy.

  17. Temporary hyposalivation induced by radiation therapy in a child; Forbigaaende straaleindusert hyposalivasjon hos barnepasient

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, J.L. [Oslo Univ., Oslo (Norway); Langberg, C.W. [Ullevaal Sykehus, Oslo (Norway)

    1997-09-01

    This case report deals with the diagnosis and treatment of hyposalivation after radical radiation therapy and cytotoxic treatment of a metastasising nasopharyngeal carcinoma in an eight-year old girl. After cancer treatment the patient suffered from xerostomia, and pronounced hyposalivation was demonstrated. Frequent chewing of sugar-free gum and use of lozenges was recommended, and the patient was followed up for one year. During this time, the values for unstimulated whole saliva increased by a factor of five, and stimulated whole saliva values increased as well, but less so. Two years after cancer treatment, the patient no longer suffers from xerostomia. 13 refs., 2 figs.

  18. Radiation collimator for use with high energy radiation beams

    International Nuclear Information System (INIS)

    Malak, S.P.

    1978-01-01

    A collimator is described for use with a beam of radiation, and in particular, for use in controlling the cross-sectional size and shape of the radiation beam and intercepting undesired off-focus radiation in an x-ray apparatus. The collimator is positioned adjacent to the source of radiation and embodies a plurality longitudinally extending leaves pivotally mounted on and between two supports, the leaves move about their pivots to close overlapping relation to define a hollow cone. The cone defines an aperture at its narrow end which can be adjusted in size and shape by rotation of the two supports which are adaptable to being moved one relative to the other, to cause an expansion or contraction of the hollow cone and correspondingly an increase or decrease of the cross-sectional size and/or shape of the radiation beam passing through the aperture

  19. Impact of head and neck cancer adaptive radiotherapy to spare the parotid glands and decrease the risk of xerostomia.

    Science.gov (United States)

    Castelli, Joel; Simon, Antoine; Louvel, Guillaume; Henry, Olivier; Chajon, Enrique; Nassef, Mohamed; Haigron, Pascal; Cazoulat, Guillaume; Ospina, Juan David; Jegoux, Franck; Benezery, Karen; de Crevoisier, Renaud

    2015-01-09

    Large anatomical variations occur during the course of intensity-modulated radiation therapy (IMRT) for locally advanced head and neck cancer (LAHNC). The risks are therefore a parotid glands (PG) overdose and a xerostomia increase. The purposes of the study were to estimate: - the PG overdose and the xerostomia risk increase during a "standard" IMRT (IMRTstd); - the benefits of an adaptive IMRT (ART) with weekly replanning to spare the PGs and limit the risk of xerostomia. Fifteen patients received radical IMRT (70 Gy) for LAHNC. Weekly CTs were used to estimate the dose distributions delivered during the treatment, corresponding either to the initial planning (IMRTstd) or to weekly replanning (ART). PGs dose were recalculated at the fraction, from the weekly CTs. PG cumulated doses were then estimated using deformable image registration. The following PG doses were compared: pre-treatment planned dose, per-treatment IMRTstd and ART. The corresponding estimated risks of xerostomia were also compared. Correlations between anatomical markers and dose differences were searched. Compared to the initial planning, a PG overdose was observed during IMRTstd for 59% of the PGs, with an average increase of 3.7 Gy (10.0 Gy maximum) for the mean dose, and of 8.2% (23.9% maximum) for the risk of xerostomia. Compared to the initial planning, weekly replanning reduced the PG mean dose for all the patients (pxerostomia by 11% (pxerostomia risk.

  20. Summary and presentation of the international workshop on beam induced energy deposition (issues, concerns, solutions)

    International Nuclear Information System (INIS)

    Soundranayagam, R.

    1991-11-01

    This report discusses: energy deposition and radiation shielding in antriproton source at FNAL; radiation issues/problems at RHIC; radiation damage to polymers; radiation effects on optical fibre in the SSC tunnel; capabilities of the Brookhaven Radiation Effects Facility; the SSC interaction region; the FLUKA code system, modifications, recent extension and experimental verification; energy particle transport calculations and comparisons with experimental data; Los Alamos High Energy Transport code system; MCNP features and applications; intercomparison of Monte Carlo codes designed for simulation of high energy hadronic cascades; event generator, DTUJET-90 and DTUNUC; Preliminary hydrodynamic calculations of beam energy deposition; MESA code calculations of material response to explosive energy deposition; Smooth particle hydrodynamic; hydrodynamic effects and mass depletion phenomena in targets; beam dump: Beam sweeping and spoilers; Design considerations to mitigate effects of accidental beam dump; SSC beam abort and absorbed; beam abort system of SSC options; unconventional scheme for beam spoilers; low β quadrupoles: Energy deposition and radioactivation; beam induces energy deposition in the SSC components; extension of SSC-SR-1033 approach to radioactivation in LHC and SSC detectors; energy deposition in the SSC low-β IR-quads; beam losses and collimation in the LHC; and radiation shielding around scrapers

  1. Dry mouth: Xerostomia and salivary gland hypofunction.

    Science.gov (United States)

    Frydrych, Agnieszka M

    2016-07-01

    Mouth dryness may present as salivary gland hypofunction (SGH), xerostomia or both. It is considered one of the most underappreciated, underdiagnosed and undermanaged oral health conditions. Despite its common presentation and adverse impact on life quality, it is also generally poorly understood. Increased awareness of the condition is important in addressing these problems. This article discusses SGH and xerostomia, and the associated intra-oral and extra-oral implications. It also summarises currently available management approaches and the evidence behind them. SGH and xerostomia are complex problems. None of the currently available management approaches are entirely satisfactory. Addressing the causative or contributing factors is therefore paramount. While oral health complaints are generally left up to the dental professional to manage, the nature of mouth dryness necessitates increased dialogue between the dental and 
medical professions to ensure optimal patient care.

  2. Risk factors, hyposalivation and impact of xerostomia on oral health-related quality of life.

    Science.gov (United States)

    Niklander, Sven; Veas, Laura; Barrera, Cristina; Fuentes, Flavio; Chiappini, Giuliana; Marshall, Maureen

    2017-01-16

    To determine xerostomia-related frequency, factors, salivary flow rates and Oral Health-Related Quality of Life (OHRQoL) of patients attending the Universidad Andrés Bello Dental School Clinic, in the city of Viña del Mar, Chile. The study involved 566 patients assessed with xerostomia, based on a single standardized questionnaire. The severity and impact of xerostomia on OHRQoL was assessed using a visual analogue scale (VAS) and the short version of the Oral Health Impact Profile Questionnaire (OHIP-14sp), respectively. Stimulated and non-stimulated salivary flow rates were obtained from a sample of patients. Xerostomia was reported in 61 patients (10.8%), comprising 50 women (83.3%) and 11 men (16.7%) (p xerostomia. Hyposalivation was found in 10 of the 35 patients with xerostomia (28.6%) and in 2 patients without it (p xerostomia had a reduced OHRQoL, compared with patients without xerostomia, as shown by the total OHIP-14sp score (p Xerostomia was a common, potentially debilitating condition with a major impact on the OHRQoL of a patient population attending a university-based dental clinic. Hyposalivation was present in almost 30% of the patients who complained of xerostomia. It is important that general dentists be aware of this condition, so that they can provide patients with a good diagnosis, treatment and follow-up.

  3. The diagnostic suitability of a xerostomia questionnaire and the association between xerostomia, hyposalivation and medication use in a group of nursing home residents

    NARCIS (Netherlands)

    Putten, Gerard van der; Brand, H.S.; Schols, J.M.; Baat, C. de

    2011-01-01

    The study objective was to explore the diagnostic suitability of the Xerostomia Inventory and the association between xerostomia, hyposalivation and medication use in a group of nursing home residents. A cross-sectional study was carried out in 50 physically impaired nursing home residents (20 men)

  4. Beam induced RF heating

    CERN Document Server

    Salvant, B; Arduini, G; Assmann, R; Baglin, V; Barnes, M J; Bartmann, W; Baudrenghien, P; Berrig, O; Bracco, C; Bravin, E; Bregliozzi, G; Bruce, R; Bertarelli, A; Carra, F; Cattenoz, G; Caspers, F; Claudet, S; Day, H; Garlasche, M; Gentini, L; Goddard, B; Grudiev, A; Henrist, B; Jones, R; Kononenko, O; Lanza, G; Lari, L; Mastoridis, T; Mertens, V; Métral, E; Mounet, N; Muller, J E; Nosych, A A; Nougaret, J L; Persichelli, S; Piguiet, A M; Redaelli, S; Roncarolo, F; Rumolo, G; Salvachua, B; Sapinski, M; Schmidt, R; Shaposhnikova, E; Tavian, L; Timmins, M; Uythoven, J; Vidal, A; Wenninger, J; Wollmann, D; Zerlauth, M

    2012-01-01

    After the 2011 run, actions were put in place during the 2011/2012 winter stop to limit beam induced radio frequency (RF) heating of LHC components. However, some components could not be changed during this short stop and continued to represent a limitation throughout 2012. In addition, the stored beam intensity increased in 2012 and the temperature of certain components became critical. In this contribution, the beam induced heating limitations for 2012 and the expected beam induced heating limitations for the restart after the Long Shutdown 1 (LS1) will be compiled. The expected consequences of running with 25 ns or 50 ns bunch spacing will be detailed, as well as the consequences of running with shorter bunch length. Finally, actions on hardware or beam parameters to monitor and mitigate the impact of beam induced heating to LHC operation after LS1 will be discussed.

  5. A longitudinal study of medication exposure and xerostomia among older people.

    Science.gov (United States)

    Murray Thomson, W; Chalmers, Jane M; John Spencer, A; Slade, Gary D; Carter, Knute D

    2006-12-01

    To describe the incidence of xerostomia among a population of older people over a 6-year period, with particular attention to medications as risk factors. Understanding the natural history of xerostomia requires longitudinal epidemiological research, but only one study has examined changes in xerostomia over time. While medication is a recognised risk factor for dry mouth, the role of particular medication categories continues to be controversial. Older South Australians (aged 60+) underwent an interview and dental examination at baseline, and these assessments were repeated 2, 5 and 11 years afterward. Medication data were collected at baseline, 5 and 11 years. Xerostomia data were collected at 5 and 11 years using the Xerostomia Inventory (XI) and a standard question. Of the 1205 dentate participants assessed at baseline, 669 remained after 5 years, and 246 were assessed at 11 years. Medication prevalence increased over the observation period, such that 94.8% of the cohort were taking at least one medication by 11 years. The prevalence of xerostomia increased from 21.4% to 24.8% between 5 and 11 years (p > 0.05), and the mean XI score increased from 20.0 (SD, 6.7) to 21.5 (SD, 7.9; p xerostomia, while 11.4% were remitted cases; 10.1% were cases at both 5 and 11 years. After controlling for gender and 'baseline' xerostomia severity (represented by the XI score at 5 years), participants who commenced taking daily aspirin after 5 years had over four times the odds of becoming incident cases, while those who commenced taking a diuretic after 5 years had nearly six times the odds of doing so. While the overall prevalence of xerostomia increased during the observation period, there was considerable instability, with one-quarter of the cohort changing their status. Medication exposure was strongly associated with the incidence of the condition, with recent exposure to diuretics or daily aspirin strongly predicting it.

  6. BEAM applications to polymer materials

    International Nuclear Information System (INIS)

    Tagawa, Seiichi

    1994-01-01

    Recently papers about beam applications to polymers have been increasing rapidly both in the fundamental and applied fields. Fairly large number of papers have been published in the fundamental aspects of radiation effects of beam applications to polymers such as pulse radiolysis and high density electronic excitation effects. A number of papers have been published in the more applied aspects of beam applications to polymers such as radiation processing and curing. The present paper describes recent beam applications to polymers. 1. Radiation Effects on Polymers; Radiation effects on polymers have been studied for more than 40 years. Most of work on radiation effects on polymers has been carried out by using high energy photon (gamma-ray) and electron beams, since polymers are sensitive to any kinds of ionizing radiation. Even non-ionizing radiation such as ultraviolet and visible light excites electronic excited states of polymers and then photo-chemical reactions of polymers are induced from the electronic excited states. Studies on radiation effects of other ionizing radiation on polymers have not been so popular for a long time. Recently application of new radiation such as ion beams to polymers have been worthy of remark in fields of advanced science and technology, since new radiation beams induce different radiation effects from those induced by high energy gamma-rays and electrons. 2. Beam Applications of Polymers; Recent progress in beam applications to polymers such as radiation processing and curing, x-ray and electron beam microlithography, and applications of new beams such as ion beams to polymers has been reviewed. (author)

  7. Photoluminescence of radiation-induced color centers in lithium fluoride thin films for advanced diagnostics of proton beams

    Energy Technology Data Exchange (ETDEWEB)

    Piccinini, M., E-mail: massimo.piccinini@enea.it; Ampollini, A.; Picardi, L.; Ronsivalle, C.; Bonfigli, F.; Libera, S.; Vincenti, M. A.; Montereali, R. M. [ENEA, C.R. Frascati, UTAPRAD, Technical Unit for Development and Applications of Radiations, Via E. Fermi 45, 00044 Frascati (Rome) (Italy); Ambrosini, F. [University Sapienza-Roma I, Piazzale Aldo Moro 5, 00185 Rome (Italy); Nichelatti, E. [ENEA, C.R. Casaccia, UTTMAT, Technical Unit for Materials Technologies, Via Anguillarese 301, 00123 S. Maria di Galeria (Rome) (Italy)

    2015-06-29

    Systematic irradiation of thermally evaporated 0.8 μm thick polycrystalline lithium fluoride films on glass was performed by proton beams of 3 and 7 MeV energies, produced by a linear accelerator, in a fluence range from 10{sup 11} to 10{sup 15} protons/cm{sup 2}. The visible photoluminescence spectra of radiation-induced F{sub 2} and F{sub 3}{sup +} laser active color centers, which possess almost overlapping absorption bands at about 450 nm, were measured under laser pumping at 458 nm. On the basis of simulations of the linear energy transfer with proton penetration depth in LiF, it was possible to obtain the behavior of the measured integrated photoluminescence intensity of proton irradiated LiF films as a function of the deposited dose. The photoluminescence signal is linearly dependent on the deposited dose in the interval from 10{sup 3} to about 10{sup 6 }Gy, independently from the used proton energies. This behavior is very encouraging for the development of advanced solid state radiation detectors based on optically transparent LiF thin films for proton beam diagnostics and two-dimensional dose mapping.

  8. Radiomodifying effect of caffeine on mammalian cellular system using gamma radiation and proton beam radiation

    International Nuclear Information System (INIS)

    Samanth, Sneha P.; Yadav, Usha; Shirsath, K.B.; Desai, Utkarsha N.; Chaurasia, Rajesh K.; Bhat, Nagesh N.; Anjaria, K.B.; Sapra, B.K.

    2016-01-01

    Caffeine is a commonly consumed neurostimulant in the world. Reports suggest the radiomodifying effects of caffeine against low Linear Energy Transfer (LET) radiation when administered pre and post irradiation by releasing checkpoint arrest. In the present report, the radioprotective and radiosensitizing ability of caffeine (10μM - 2mM) were studied on Chinese Hamster Ovary (CRO) cell line against low as well as high LET radiation when administered pre, post and continuously during radiation. Effect of caffeine treatment on the genotoxicity induced by gamma and proton beam radiation was assessed by micronucleus assay. Effect of caffeine treatment on clonogenic survival of irradiated cells was also assessed

  9. Radiation-induced dental caries, prevention and treatment - A systematic review.

    Science.gov (United States)

    Gupta, Nishtha; Pal, Manoj; Rawat, Sheh; Grewal, Mandeep S; Garg, Himani; Chauhan, Deepika; Ahlawat, Parveen; Tandon, Sarthak; Khurana, Ruparna; Pahuja, Anjali K; Mayank, Mayur; Devnani, Bharti

    2015-01-01

    Treatment of head and neck cancers (HNCs) involves radiotherapy. Patients undergoing radiotherapy for HNCs are prone to dental complications. Radiotherapy to the head and neck region causes xerostomia and salivary gland dysfunction which dramatically increases the risk of dental caries and its sequelae. Radiation therapy (RT) also affects the dental hard tissues increasing their susceptibility to demineralization following RT. Postradiation caries is a rapidly progressing and highly destructive type of dental caries. Radiation-related caries and other dental hard tissue changes can appear within the first 3 months following RT. Hence, every effort should be focused on prevention to manage patients with severe caries. This can be accomplished through good preoperative dental treatment, frequent dental evaluation and treatment after RT (with the exception of extractions), and consistent home care that includes self-applied fluoride. Restorative management of radiation caries can be challenging. The restorative dentist must consider the altered dental substrate and a hostile oral environment when selecting restorative materials. Radiation-induced changes in enamel and dentine may compromise bonding of adhesive materials. Consequently, glass ionomer cements have proved to be a better alternative to composite resins in irradiated patients. Counseling of patients before and after radiotherapy can be done to make them aware of the complications of radiotherapy and thus can help in preventing them.

  10. The Split Denture: Managing Xerostomia in Denture Patients: A Case Report

    OpenAIRE

    Dabas, Nupur; Phukela, Sumit Singh; Yadav, Harish

    2011-01-01

    Wearing complete dentures can be an extremely uncomfortable experience for the people with Xerostomia. Various treatment modalities have been suggested in the literature to overcome the problem of xerostomia in complete denture patients. Incorporating reservoirs containing salivary substitutes, into dentures, is one of these treatment modalities. This paper presents case report of a patient suffering from xerostomia who was successfully treated with a new form of reservoir dentures. This new ...

  11. Xerostomia related to HIV infection /AIDS: a critical review

    Directory of Open Access Journals (Sweden)

    Adriana Maria Fuzer Grael TINÓS

    Full Text Available Introduction: The presence of oral manifestations in HIV positive individuals is quite common. Xerostomia appears as one of the most frequent problems and may lead to a reduction in the quality of life of this population. Objective: This study was a critical review of the relationship between xerostomia and HIV infection, to attract the attention of dentists on the importance of dental care to these patients. Material and method: We included articles published between 2000 and 2009, indexed in PUBMED database. The descriptors used were "HIV" and "xerostomia", the exclusion criteria adopted were: the absence of these descriptors associated, non-location of the full-text, articles based on case studies or case series and the absence of the abstract in the database. Result: Based on studies in the review, it can be said that the xerostomia is a common manifestation of HIV infection, predisposing the patient to several other oral problems. Among the risk factors for its occurrence it was reported: low counts of CD4+ T cells, high plasma viral load, the use of some medications and antiretroviral therapy. Conclusion: The HIV/AIDS can change the salivary glands, and were considered important risk factors for the occurrence of xerostomia the presence of didanosine and the drug class which corresponds to protease inhibitors in antiretroviral therapy.

  12. A beam radiation monitoring and protection system for AGS secondary beams

    International Nuclear Information System (INIS)

    Levine, G.S.

    1978-01-01

    A commercially available radiation monitor using a scintillation detector was modified for charged particle beam monitoring. The device controls access to secondary beams of the AGS and limits beam intensity

  13. Diagnosis and management of xerostomia and hyposalivation

    Directory of Open Access Journals (Sweden)

    Villa A

    2014-12-01

    Full Text Available Alessandro Villa,1,2 Christopher L Connell,3 Silvio Abati4 1Division of Oral Medicine and Dentistry, Brigham and Women’s Hospital, Boston, MA, USA; 2Department of Oral Medicine, Infection and Immunity, Harvard School of Dental Medicine, Boston, MA, USA; 3Department of General Dentistry, Boston University Henry M Goldman School of Dental Medicine, Boston, MA, USA; 4Dental Clinic, Department of Health Sciences, University of Milan, Milano, Italy Abstract: Xerostomia, the subjective complaint of dry mouth, and hyposalivation remain a significant burden for many individuals. Diagnosis of xerostomia and salivary gland hypofunction is dependent upon a careful and detailed history and thorough oral examination. There exist many options for treatment and symptom management: salivary stimulants, topical agents, saliva substitutes, and systemic sialogogues. The aim of this review is to investigate the current state of knowledge on management and treatment of patients affected by xerostomia and/or hyposalivation. Keyword: saliva stimulation, dry mouth, saliva substitutes, sialogogues

  14. Design and Selection of Machine Learning Methods Using Radiomics and Dosiomics for Normal Tissue Complication Probability Modeling of Xerostomia

    Directory of Open Access Journals (Sweden)

    Hubert S. Gabryś

    2018-03-01

    Full Text Available PurposeThe purpose of this study is to investigate whether machine learning with dosiomic, radiomic, and demographic features allows for xerostomia risk assessment more precise than normal tissue complication probability (NTCP models based on the mean radiation dose to parotid glands.Material and methodsA cohort of 153 head-and-neck cancer patients was used to model xerostomia at 0–6 months (early, 6–15 months (late, 15–24 months (long-term, and at any time (a longitudinal model after radiotherapy. Predictive power of the features was evaluated by the area under the receiver operating characteristic curve (AUC of univariate logistic regression models. The multivariate NTCP models were tuned and tested with single and nested cross-validation, respectively. We compared predictive performance of seven classification algorithms, six feature selection methods, and ten data cleaning/class balancing techniques using the Friedman test and the Nemenyi post hoc analysis.ResultsNTCP models based on the parotid mean dose failed to predict xerostomia (AUCs < 0.60. The most informative predictors were found for late and long-term xerostomia. Late xerostomia correlated with the contralateral dose gradient in the anterior–posterior (AUC = 0.72 and the right–left (AUC = 0.68 direction, whereas long-term xerostomia was associated with parotid volumes (AUCs > 0.85, dose gradients in the right–left (AUCs > 0.78, and the anterior–posterior (AUCs > 0.72 direction. Multivariate models of long-term xerostomia were typically based on the parotid volume, the parotid eccentricity, and the dose–volume histogram (DVH spread with the generalization AUCs ranging from 0.74 to 0.88. On average, support vector machines and extra-trees were the top performing classifiers, whereas the algorithms based on logistic regression were the best choice for feature selection. We found no advantage in using data cleaning or class balancing

  15. Impact of head and neck cancer adaptive radiotherapy to spare the parotid glands and decrease the risk of xerostomia

    International Nuclear Information System (INIS)

    Castelli, Joel; Simon, Antoine; Louvel, Guillaume; Henry, Olivier; Chajon, Enrique; Nassef, Mohamed; Haigron, Pascal; Cazoulat, Guillaume; Ospina, Juan David; Jegoux, Franck; Benezery, Karen; Crevoisier, Renaud de

    2015-01-01

    Large anatomical variations occur during the course of intensity-modulated radiation therapy (IMRT) for locally advanced head and neck cancer (LAHNC). The risks are therefore a parotid glands (PG) overdose and a xerostomia increase. The purposes of the study were to estimate: - the PG overdose and the xerostomia risk increase during a “standard” IMRT (IMRT std ); - the benefits of an adaptive IMRT (ART) with weekly replanning to spare the PGs and limit the risk of xerostomia. Fifteen patients received radical IMRT (70 Gy) for LAHNC. Weekly CTs were used to estimate the dose distributions delivered during the treatment, corresponding either to the initial planning (IMRT std ) or to weekly replanning (ART). PGs dose were recalculated at the fraction, from the weekly CTs. PG cumulated doses were then estimated using deformable image registration. The following PG doses were compared: pre-treatment planned dose, per-treatment IMRT std and ART. The corresponding estimated risks of xerostomia were also compared. Correlations between anatomical markers and dose differences were searched. Compared to the initial planning, a PG overdose was observed during IMRT std for 59% of the PGs, with an average increase of 3.7 Gy (10.0 Gy maximum) for the mean dose, and of 8.2% (23.9% maximum) for the risk of xerostomia. Compared to the initial planning, weekly replanning reduced the PG mean dose for all the patients (p < 0.05). In the overirradiated PG group, weekly replanning reduced the mean dose by 5.1 Gy (12.2 Gy maximum) and the absolute risk of xerostomia by 11% (p < 0.01) (30% maximum). The PG overdose and the dosimetric benefit of replanning increased with the tumor shrinkage and the neck thickness reduction (p < 0.001). During the course of LAHNC IMRT, around 60% of the PGs are overdosed of 4 Gy. Weekly replanning decreased the PG mean dose by 5 Gy, and therefore by 11% the xerostomia risk

  16. Evaluation of xerostomia and taste disturbance after radiotherapy of patients with head and neck lesion

    International Nuclear Information System (INIS)

    Toda, Yukihiro

    2002-01-01

    Because of high sensitivity to radiation, radiotherapy to the head and neck cancer is often conducted for purposes of functional preservation. However, the salivary glands and oral cavity must be included in the irradiation field. Thus, an inflammatory reaction of the oral mucosa to the radiotherapy is inevitable, and xerostomia, taste disturbance, and pain appear in the early stage of the treatment. These side effects sometimes cause not only interrupt or change planned treatment but also influence patients' Quality of Life after treatment. Thus, we conducted, in the form of questionnaire surveys, subjective and objective evaluations in respect to xerostomia and taste disturbance, and assessed the usefulness of the evaluations. The subjects were 40 patients who had received the radiotherapy in the major salivary glands, such as parotid glands, and almost the whole tongue, but who had not undergo a resection of the major salivary glands or tongue. The degree of damage to the salivary glands and taste were evaluated, subjectively and objectively. The subjective evaluation was conducted by questionnaires given to the patients. As for the objective evaluation, xerostomia was evaluated by measuring the salivary amount, while the taste disturbance was examined in 27 patients using taste disks. The results showed a positive correlation, indicating that the evaluation of xerostomia and taste disturbance using questionnaires is useful. The salivary amount was the least at six months after the radiotherapy, then increased gradually, and 24 months later, improved to a level similar to that seen immediately after the radiotherapy. The taste disturbance also improved gradually over the 24 months following radiotherapy. (author)

  17. Evaluation of xerostomia and taste disturbance after radiotherapy of patients with head and neck lesion

    Energy Technology Data Exchange (ETDEWEB)

    Toda, Yukihiro [Kurume Univ., Fukuoka (Japan). School of Medicine

    2002-10-01

    Because of high sensitivity to radiation, radiotherapy to the head and neck cancer is often conducted for purposes of functional preservation. However, the salivary glands and oral cavity must be included in the irradiation field. Thus, an inflammatory reaction of the oral mucosa to the radiotherapy is inevitable, and xerostomia, taste disturbance, and pain appear in the early stage of the treatment. These side effects sometimes cause not only interrupt or change planned treatment but also influence patients' Quality of Life after treatment. Thus, we conducted, in the form of questionnaire surveys, subjective and objective evaluations in respect to xerostomia and taste disturbance, and assessed the usefulness of the evaluations. The subjects were 40 patients who had received the radiotherapy in the major salivary glands, such as parotid glands, and almost the whole tongue, but who had not undergo a resection of the major salivary glands or tongue. The degree of damage to the salivary glands and taste were evaluated, subjectively and objectively. The subjective evaluation was conducted by questionnaires given to the patients. As for the objective evaluation, xerostomia was evaluated by measuring the salivary amount, while the taste disturbance was examined in 27 patients using taste disks. The results showed a positive correlation, indicating that the evaluation of xerostomia and taste disturbance using questionnaires is useful. The salivary amount was the least at six months after the radiotherapy, then increased gradually, and 24 months later, improved to a level similar to that seen immediately after the radiotherapy. The taste disturbance also improved gradually over the 24 months following radiotherapy. (author)

  18. Systematic literature review: xerostomia in advanced cancer patients.

    Science.gov (United States)

    Hanchanale, Sarika; Adkinson, Lucy; Daniel, Sunitha; Fleming, Michelle; Oxberry, Stephen G

    2015-03-01

    Dry mouth (xerostomia) is one of the commonest symptoms in cancer patients and can adversely affect quality of life. The aim of this review was to determine the effectiveness of pharmacological and non-pharmacological interventions in treating xerostomia in adult advanced cancer patients. The literature search was performed in February 2014 using databases including EMBASE, MEDLINE, CINAHL, BNI and Cochrane library. The search was carried out using standard MeSH terms and was limited to adult population and English language. Studies investigating xerostomia secondary to head and neck cancer treatment and autoimmune disease were excluded. Titles and abstracts were screened and reviewed for eligibility. Only studies involving primary research were included in the analysis. Six studies met the eligibility criteria for review: three randomized controlled trials and three prospective studies. The quality assessment and reporting was performed using PRISMA, Jadad and STROBE. These studies compared acupuncture, pilocarpine, Saliva Orthana and chewing gum with each other or with placebo. All interventions were considered effective in treating xerostomia. However, effectiveness versus placebo could not be demonstrated for Saliva Orthana. Meta-analysis could not be performed due to heterogeneity of the study type and intervention. Limited published data exists reporting the effectiveness of measures in the treatment of xerostomia in cancer patients. Based on primary research of low quality, firm conclusions cannot be drawn. However, pilocarpine, artificial saliva, chewing gum and acupuncture can be tried based on the available data. This highlights the explicit need to improve our evidence base. Properly constructed randomized controlled trials demonstrating effectiveness of pharmacological and non-pharmacological interventions for dry mouth are required.

  19. Xerostomia, Hyposalivation, and Salivary Flow in Diabetes Patients.

    Science.gov (United States)

    López-Pintor, Rosa María; Casañas, Elisabeth; González-Serrano, José; Serrano, Julia; Ramírez, Lucía; de Arriba, Lorenzo; Hernández, Gonzalo

    2016-01-01

    The presence of xerostomia and hyposalivation is frequent among diabetes mellitus (DM) patients. It is not clear if the presence of xerostomia and hyposalivation is greater in DM than non-DM patients. The aims of this systematic review are (1) to compare the prevalence rates of xerostomia, (2) to evaluate the salivary flow rate, and (3) to compare the prevalence rates of hyposalivation in DM versus non-DM population. This systematic review was conducted according to the PRISMA group guidelines by performing systematic literature searches in biomedical databases from 1970 until January 18th, 2016. All studies showed higher prevalence of xerostomia in DM patients in relation to non-DM population, 12.5%-53.5% versus 0-30%. Studies that analyzed the quantity of saliva in DM population in relation to non-DM patients reported higher flow rates in non-DM than in DM patients. The variation flow rate among different studies in each group (DM/CG) is very large. Only one existing study showed higher hyposalivation prevalence in DM than non-DM patients (45% versus 2.5%). In addition, quality assessment showed the low quality of the existing studies. We recommend new studies that use more precise and current definitions concerning the determination and diagnosis of DM patients and salivary flow collection.

  20. Transition radiation electron beam diagnostic study at ATF

    International Nuclear Information System (INIS)

    Qiu, X.Z.; Wang, X.J.; Batchelor, K.; Ben-Zvi, I.

    1995-01-01

    Recently we have started a program to develop transition radiation based electron beam diagnostics at the Accelerator Test Facility at Brookhaven National Laboratory. In this paper, we will discuss a technique to estimate the lower limit in electron beam divergence measurement with single foil transition radiation and two-foil transition radiation interferometer. Preliminary experimental data from 4.5 MeV electron beam will be presented

  1. A Guide to Medications Inducing Salivary Gland Dysfunction, Xerostomia, and Subjective Sialorrhea: A Systematic Review Sponsored by the World Workshop on Oral Medicine VI

    DEFF Research Database (Denmark)

    Wolff, Andy; Joshi, Revan Kumar; Ekström, Jörgen

    2017-01-01

    , and strength of evidence. We found 56 chemical substances with a higher level of evidence and 50 with a moderate level of evidence of causing the above-mentioned disorders. At the first level of the Anatomical Therapeutic Chemical (ATC) classification system, 9 of 14 anatomical groups were represented, mainly......: While xerostomia was a commonly reported outcome, objectively measured salivary flow rate was rarely reported. Moreover, xerostomia was mostly assessed as an adverse effect rather than the primary outcome of medication use. This study may not include some medications that could cause xerostomia when...

  2. Shortening the xerostomia inventory

    NARCIS (Netherlands)

    Thomson, W.M.; Putten, G.J. van der; Baat, C. de; Ikebe, K.; Matsuda, K.; Enoki, K.; Hopcraft, M.S.; Ling, G.Y.

    2011-01-01

    OBJECTIVES: The aim of this study was to determine the validity and properties of the Summated Xerostomia Inventory-Dutch Version in samples from Australia, The Netherlands, Japan, and New Zealand. STUDY DESIGN: Six cross-sectional samples of older people from The Netherlands (n = 50), Australia (n

  3. Radiative cooling of relativistic electron beams

    International Nuclear Information System (INIS)

    Huang, Z.

    1998-05-01

    Modern high-energy particle accelerators and synchrotron light sources demand smaller and smaller beam emittances in order to achieve higher luminosity or better brightness. For light particles such as electrons and positrons, radiation damping is a natural and effective way to obtain low emittance beams. However, the quantum aspect of radiation introduces random noise into the damped beams, yielding equilibrium emittances which depend upon the design of a specific machine. In this dissertation, the author attempts to make a complete analysis of the process of radiation damping and quantum excitation in various accelerator systems, such as bending magnets, focusing channels and laser fields. Because radiation is formed over a finite time and emitted in quanta of discrete energies, he invokes the quantum mechanical approach whenever the quasiclassical picture of radiation is insufficient. He shows that radiation damping in a focusing system is fundamentally different from that in a bending system. Quantum excitation to the transverse dimensions is absent in a straight, continuous focusing channel, and is exponentially suppressed in a focusing-dominated ring. Thus, the transverse normalized emittances in such systems can in principle be damped to the Compton wavelength of the electron, limited only by the Heisenberg uncertainty principle. In addition, he investigates methods of rapid damping such as radiative laser cooling. He proposes a laser-electron storage ring (LESR) where the electron beam in a compact storage ring repetitively interacts with an intense laser pulse stored in an optical resonator. The laser-electron interaction gives rise to rapid cooling of electron beams and can be used to overcome the space charge effects encountered in a medium energy circular machine. Applications to the designs of low emittance damping rings and compact x-ray sources are also explored

  4. Radiative cooling of relativistic electron beams

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Zhirong [Stanford Univ., CA (United States)

    1998-05-01

    Modern high-energy particle accelerators and synchrotron light sources demand smaller and smaller beam emittances in order to achieve higher luminosity or better brightness. For light particles such as electrons and positrons, radiation damping is a natural and effective way to obtain low emittance beams. However, the quantum aspect of radiation introduces random noise into the damped beams, yielding equilibrium emittances which depend upon the design of a specific machine. In this dissertation, the author attempts to make a complete analysis of the process of radiation damping and quantum excitation in various accelerator systems, such as bending magnets, focusing channels and laser fields. Because radiation is formed over a finite time and emitted in quanta of discrete energies, he invokes the quantum mechanical approach whenever the quasiclassical picture of radiation is insufficient. He shows that radiation damping in a focusing system is fundamentally different from that in a bending system. Quantum excitation to the transverse dimensions is absent in a straight, continuous focusing channel, and is exponentially suppressed in a focusing-dominated ring. Thus, the transverse normalized emittances in such systems can in principle be damped to the Compton wavelength of the electron, limited only by the Heisenberg uncertainty principle. In addition, he investigates methods of rapid damping such as radiative laser cooling. He proposes a laser-electron storage ring (LESR) where the electron beam in a compact storage ring repetitively interacts with an intense laser pulse stored in an optical resonator. The laser-electron interaction gives rise to rapid cooling of electron beams and can be used to overcome the space charge effects encountered in a medium energy circular machine. Applications to the designs of low emittance damping rings and compact x-ray sources are also explored.

  5. Radiation effects of ion beams on polymers

    International Nuclear Information System (INIS)

    Tagawa, Seiichi

    1993-01-01

    Recent progress in the radiation effects of ion beams on polymers are reviewed briefly. Our recent work on the radiation effects of ion beams on polystyrene thin films on silicon wafers and time resolved emission studies on polymers are described. (orig.)

  6. Induced radioactivity in Bevatron concrete radiation shielding blocks

    International Nuclear Information System (INIS)

    Moeller, G.C.; Donahue, R.J.

    1994-07-01

    The Bevatron accelerated protons up to 6.2 GeV and heavy ions up to 2.1 GeV/amu. It operated from 1954 to 1993. Radioactivity was induced in some concrete radiation shielding blocks by prompt radiation. Prompt radiation is primarily neutrons and protons that were generated by the Bevatron's primary beam interactions with targets and other materials. The goal was to identify the gamma-ray emitting nuclides (t 1/2 > 0.5 yr) that could be present in the concrete blocks and estimate the depth at which the maximum radioactivity presently occurs. It is shown that the majority of radioactivity was produced via thermal neutron capture by trace elements present in concrete. The depth of maximum thermal neutron flux, in theory, corresponds with the depth of maximum induced activity. To estimate the depth at which maximum activity occurs in the concrete blocks, the LAHET Code System was used to calculate the depth of maximum thermal neutron flux. The primary beam interactions that generate the neutrons are also modeled by the LAHET Code System

  7. Beam-limiting and radiation-limiting interlocks

    International Nuclear Information System (INIS)

    Macek, R.J.

    1996-01-01

    This paper reviews several aspects of beam-limiting and radiation- limiting interlocks used for personnel protection at high-intensity accelerators. It is based heavily on the experience at the Los Alamos Neutron Science Center (LANSCE) where instrumentation-based protection is used extensively. Topics include the need for ''active'' protection systems, system requirements, design criteria, and means of achieving and assessing acceptable reliability. The experience with several specific devices (ion chamber-based beam loss interlock, beam current limiter interlock, and neutron radiation interlock) designed and/or deployed to these requirements and criteria is evaluated

  8. Acupuncture for pilocarpine-resistant xerostomia following radiotherapy for head and neck malignancies

    International Nuclear Information System (INIS)

    Johnstone, Peter A.S.; Peng, Y. Peter; May, Byron C.; Inouye, Warren S.; Niemtzow, Richard C.

    2001-01-01

    Objective: Xerostomia is a frequent and potentially debilitating toxicity of radiotherapy (XRT) for cancers of the head and neck. This report describes the use of acupuncture as palliation for such patients. Methods and Materials: Eighteen patients with xerostomia refractory to pilocarpine therapy after XRT for head and neck malignancy were offered acupuncture as palliation. All patients are without evidence of cancer recurrence at the primary site. Acupuncture was provided to three auricular points and one digital point bilaterally, with electrostimulation used variably. The Xerostomia Inventory (XI) was administered retrospectively to provide an objective measure of efficacy. Results: Acupuncture contributed to relief from xerostomia to varying degrees. Palliative effect as measured by the XI varied from nil to robust (pre- minus post- therapy values of over 20 points). Nine patients had benefit of over 10 points on the XI. Conclusions: Acupuncture reduces xerostomia in some patients who are otherwise refractory to best current management

  9. Sleep quality in patients with xerostomia: a prospective and randomized case-control study.

    Science.gov (United States)

    Lopez-Jornet, Pia; Lucero Berdugo, Maira; Fernandez-Pujante, Alba; C, Castillo Felipe; Lavella C, Zamora; A, Pons-Fuster; J, Silvestre Rangil; Silvestre, Francisco Javier

    2016-01-01

    Objectives To investigate sleep quality, anxiety/depression and quality-of-life in patients with xerostomia. Materials and methods This prospective, observational, cross-sectional study was conducted among a group of xerostomia patients (n = 30) compared with 30 matched control subjects. The following evaluation scales were used to assess the psychological profile of each patient: the Hospital Anxiety and Depression Scale, the Oral Health Impact Profile-14 (OHIP-14), the Xerostomia Inventory, the Pittsburgh Sleep Quality Index (PSQI) and the Epworth Sleepiness Scale (ESS). Results The PSQI obtained 5.3 3 ± 1.78 for patients with xerostomia compared with 4.26 ± 1.01 for control subjects (p = 0.006); ESS obtained 5.7 ± 2.1 for test patients vs 4.4 0 ± 1 for control subjects (p = 0.010). Statistical regression analysis showed that xerostomia was significantly associated with depression (p = 0.027). Conclusions Patients with xerostomia exhibited significant decreases in sleep quality compared with control subjects.

  10. Impact of xerostomia on the quality of life of adolescents with type 1 diabetes mellitus.

    Science.gov (United States)

    Busato, Ivana Maria Saes; Ignácio, Sérgio Aparecido; Brancher, João Armando; Grégio, Ana Maria Trindade; Machado, Maria Angela Naval; Azevedo-Alanis, Luciana Reis

    2009-09-01

    To evaluate the impact of xerostomia on the quality of life (QOL) of adolescents with type 1 diabetes mellitus (DM1). The sample was comprised of 51 adolescents with DM1. Diabetic status was determined by glycosylated hemoglobin (HbG) and capillary glucose (CG) tests. Poor metabolic control was defined as HbG >8.0% and CG 130 mg/dL. Measurement of salivary flow was performed by means of stimulated saliva collection. Xerostomia was detected by asking a question about the sensation of having "dry mouth," and OHIP-14 was used to measure the impact of xerostomia on QOL. A total of 52.9% of subjects presented with xerostomia and 40.8% with hyposalivation. Significant differences between the subjects with and without xerostomia regarding metabolic control levels were not observed (P > .05). However, OHIP-14 scores were significantly different between the subjects with and without xerostomia (P < .001). Xerostomia is frequent and has a negative impact on QOL of adolescents with DM1.

  11. Salivary gland dysfunction and xerostomia in Sjögren's syndrome

    DEFF Research Database (Denmark)

    Jensen, Siri Beier; Vissink, Arjan

    2014-01-01

    In this article, salivary gland dysfunction and xerostomia in Sjögren's syndrome (SS) are discussed, with a focus on the pathophysiology of salivary dysfunction in SS, the clinical presentation of dry mouth in SS, how to assess salivary gland hypofunction and xerostomia in SS, and the impact...

  12. Radiation-induced chondrosarcoma of the maxilla 7-year after combined chemoradiation for tonsillar lymphoma.

    Science.gov (United States)

    Mohammadianpanah, M; Gramizadeh, B; Omidvari, Sh; Mosalaei, A

    2004-01-01

    Radiation-induced sarcoma is a rare complication of radiation therapy. We report a case of radiation-induced chondrosarcoma of the maxilla. An 80-year-old Persian woman developed radiation-induced chondrosarcoma of the left maxilla 7 years after combined chemotherapy and external beam radiation therapy for the Ann Arbor stage IE malignant lymphoma of the right tonsil. She underwent suboptimal tumour resection and died due to extensive locoregional disease 8 months later. An English language literature search of Medline using the terms chondrosarcoma, radiation-induced sarcoma and maxilla revealed only one earlier reported case. We describe the clinical and pathological features of this case and review the literature on radiation-induced sarcomas.

  13. Radiation-induced chondrosarcoma of the maxilla 7-year after combined chemoradiation for tonsillar lymphoma

    Directory of Open Access Journals (Sweden)

    Mohammadianpanah M

    2004-07-01

    Full Text Available Radiation-induced sarcoma is a rare complication of radiation therapy. We report a case of radiation-induced chondrosarcoma of the maxilla. An 80-year-old Persian woman developed radiation-induced chondrosarcoma of the left maxilla 7 years after combined chemotherapy and external beam radiation therapy for the Ann Arbor stage IE malignant lymphoma of the right tonsil. She underwent suboptimal tumour resection and died due to extensive locoregional disease 8 months later. An English language literature search of Medline using the terms chondrosarcoma, radiation-induced sarcoma and maxilla revealed only one earlier reported case. We describe the clinical and pathological features of this case and review the literature on radiation-induced sarcomas.

  14. Understanding of xerostomia and strategies for the development of artificial saliva.

    Science.gov (United States)

    Kho, Hong-Seop

    2014-01-01

    Xerostomia is becoming a major issue in dental and medical clinics with an increase of aged population. Medication is the most common etiology of xerostomia, while the most severe xerostomia generally occurs in patients with a history of head and neck radiotherapy. Xerostomic patients usually suffer from diminished quality of life due to various symptoms and complications. Decreased salivary output is a definite objective sign, but oral mucosal wetness is a more reliable factor for the evaluation of xerostomia. At present there are no effective therapeutic methods for the treatment of xerostomia. Sialogogues may have problematic side effects and their therapeutic effects last only brief duration. Artificial saliva typically does not produce satisfactory results in therapeutic efficacy. Therefore, further research and development of better therapeutic modalities are necessary. The basic concept for the development of ideal and functional artificial saliva is the mimicry of natural human saliva. We need proper candidate molecules and antimicrobial supplements to simulate the rheological and biological properties of human saliva. We also need better understanding of the interactions between the ingredients of artificial saliva themselves and between the ingredients and components of human saliva both in solution and on surface phases. In addition, we need accepted measures to evaluate the efficacy of artificial saliva. In conclusion, for the development of ideal artificial saliva, research based on the understanding of pathophysiology of xerostomia and knowledge about rheological and biological functions of human saliva are necessary.

  15. Scattered radiation from applicators in clinical electron beams

    International Nuclear Information System (INIS)

    Battum, L J van; Zee, W van der; Huizenga, H

    2003-01-01

    In radiotherapy with high-energy (4-25 MeV) electron beams, scattered radiation from the electron applicator influences the dose distribution in the patient. In most currently available treatment planning systems for radiotherapy this component is not explicitly included and handled only by a slight change of the intensity of the primary beam. The scattered radiation from an applicator changes with the field size and distance from the applicator. The amount of scattered radiation is dependent on the applicator design and on the formation of the electron beam in the treatment head. Electron applicators currently applied in most treatment machines are essentially a set of diaphragms, but still do produce scattered radiation. This paper investigates the present level of scattered dose from electron applicators, and as such provides an extensive set of measured data. The data provided could for instance serve as example input data or benchmark data for advanced treatment planning algorithms which employ a parametrized initial phase space to characterize the clinical electron beam. Central axis depth dose curves of the electron beams have been measured with and without applicators in place, for various applicator sizes and energies, for a Siemens Primus, a Varian 2300 C/D and an Elekta SLi accelerator. Scattered radiation generated by the applicator has been found by subtraction of the central axis depth dose curves, obtained with and without applicator. Scattered radiation from Siemens, Varian and Elekta electron applicators is still significant and cannot be neglected in advanced treatment planning. Scattered radiation at the surface of a water phantom can be as high as 12%. Scattered radiation decreases almost linearly with depth. Scattered radiation from Varian applicators shows clear dependence on beam energy. The Elekta applicators produce less scattered radiation than those of Varian and Siemens, but feature a higher effective angular variance. The scattered

  16. Unilateral versus bilateral irradiation in squamous cell head and neck cancer in relation to patient-rated xerostomia and sticky saliva

    NARCIS (Netherlands)

    Jellema, Anke Petra; Slotman, Ben J.; Doornaert, Patricia; Leemans, C. Rene; Langendijk, Johannes A.

    2007-01-01

    Background and purpose: To investigate the association between radiation technique with patient-rated moderate and severe xerostomia and sticky saliva. Materials and methods: One hundred and fifty patients treated with bilateral or unilateral irradiation for head and neck cancer were included. The

  17. Xerostomia Due to Systemic Disease: A Review of 20 Conditions ...

    African Journals Online (AJOL)

    Xerostomia is a common complaint of nearly half of the elderly population and about one‑fifth of younger adults. It causes several signs and symptoms, and compromise oral functions and health‑related quality‑of‑life. Multiple reasons are proposed to describe the etiology of xerostomia such as local factors, psychogenic ...

  18. Different saliva substitutes for treatment of xerostomia following radiotherapy. A prospective crossover study

    International Nuclear Information System (INIS)

    Momm, F.; Volegova-Neher, N.J.; Guttenberger, R.; Schulte-Moenting, J.

    2005-01-01

    Background and purpose: xerostomia is an important chronic side effect of radiotherapy in the head and neck area. The authors investigated the efficacy of different artificial saliva compounds in patients with postirradiation xerostomia. Patients and methods: in 120 patients with xerostomia after radiotherapy for head and neck cancer, four different saliva substitute compounds (gel, carmellose spray, oil, mucin spray) were tested in a prospective crossover design. Xerostomia at baseline and under treatment with each compound was measured with a questionnaire approved in a pilot trial. Results: all compounds significantly improved xerostomia when compared to baseline situation (p < 0.0001). The gel was rated best, the carmellose spray was rated worst by the patients, but the single compounds did not differ significantly in their effects. In spite of this result, most patients chose the carmellose spray as their favorite compound. This is due to its good taste and easy handling, which play an important role for the acceptance of the products. Big individual differences in the preference of the single compounds were found. Conclusion: for most patients considerable relief from xerostomia can be reached by saliva substitutes. Thus, every patient with xerostomia should be given different artificial saliva compounds for a test period. This will help to find the individually best way to cope with the dry mouth. (orig.)

  19. Xerostomia, Hyposalivation, and Salivary Flow in Diabetes Patients

    Directory of Open Access Journals (Sweden)

    Rosa María López-Pintor

    2016-01-01

    Full Text Available The presence of xerostomia and hyposalivation is frequent among diabetes mellitus (DM patients. It is not clear if the presence of xerostomia and hyposalivation is greater in DM than non-DM patients. The aims of this systematic review are (1 to compare the prevalence rates of xerostomia, (2 to evaluate the salivary flow rate, and (3 to compare the prevalence rates of hyposalivation in DM versus non-DM population. This systematic review was conducted according to the PRISMA group guidelines by performing systematic literature searches in biomedical databases from 1970 until January 18th, 2016. All studies showed higher prevalence of xerostomia in DM patients in relation to non-DM population, 12.5%–53.5% versus 0–30%. Studies that analyzed the quantity of saliva in DM population in relation to non-DM patients reported higher flow rates in non-DM than in DM patients. The variation flow rate among different studies in each group (DM/CG is very large. Only one existing study showed higher hyposalivation prevalence in DM than non-DM patients (45% versus 2.5%. In addition, quality assessment showed the low quality of the existing studies. We recommend new studies that use more precise and current definitions concerning the determination and diagnosis of DM patients and salivary flow collection.

  20. Anomalous x-ray radiation of beam plasma

    International Nuclear Information System (INIS)

    Dimitrov, S.K.; Zavyalov, M.A.; Mikhin, S.G.; Tarasenkov, V.A.; Telkovskij, V.G.; Khrabrov, V.A.

    1985-01-01

    The properties of non-equilibrium stationary plasma under the conditions of the planned plasma-chemical reactors based on beam-plasma discharge were investigated. The x-ray spectrum of the beam-plasma was measured and anomalous spectral properties were analyzed. Starting with some critical pressure the anomalous radiation was added to the classical bremsstrahlung spectrum. The occurrence of anomalous radiation can be used to diagnose the condition of beam transportation in such systems. (D.Gy.)

  1. Dry Eye Disease Patients with Xerostomia Report Higher Symptom Load and Have Poorer Meibum Expressibility.

    Science.gov (United States)

    Fostad, Ida G; Eidet, Jon R; Utheim, Tor P; Ræder, Sten; Lagali, Neil S; Messelt, Edvard B; Dartt, Darlene A

    2016-01-01

    The purpose of the study was to investigate if xerostomia (dry mouth) is associated with symptoms and signs of dry eye disease (DED). At the Norwegian Dry Eye Clinic, patients with symptomatic DED with different etiologies were consecutively included in the study. The patients underwent a comprehensive ophthalmological work-up and completed self-questionnaires on symptoms of ocular dryness (Ocular Surface Disease Index [OSDI] and McMonnies Dry Eye Questionnaire) and the Sjögren's syndrome (SS) questionnaire (SSQ). Three hundred and eighteen patients (52% women and 48% men) with DED were included. Patient demographics were: 0 to 19 years (1%), 20 to 39 (25%), 40 to 59 (34%), 60 to 79 (35%) and 80 to 99 (5%). Xerostomia, defined as "daily symptoms of dry mouth the last three months" (as presented in SSQ) was reported by 23% of the patients. Female sex was more common among patients with xerostomia (81%) than among non-xerostomia patients (44%; Pxerostomia (60 ± 15 years) were older than those without xerostomia (51 ± 17; Pxerostomia patients (65%) than among non-xerostomia patients (35%; Pxerostomia had a higher OSDI score (19.0 ± 10.0) than those without xerostomia (12.9 ± 8.0; Pxerostomia patients had more pathological meibum expressibility (0.9 ± 0.7) than those without xerostomia (0.7 ± 0.8; P = 0.046). Comparisons of OSDI and ocular signs were performed after controlling for the effects of sex, age and the number of systemic prescription drugs used. In conclusion, xerostomia patients demonstrated a higher DED symptom load and had poorer meibum expressibility than non-xerostomia patients.

  2. Management of cancer therapy-induced oral mucositis pain and xerostomia with extra- and intra oral laser irradiation

    Science.gov (United States)

    Libik, T. V.; Gileva, O. S.; Danilov, K. V.; Grigorev, S. S.; Pozdnyakova, A. A.

    2017-09-01

    This study evaluated the efficacy of combined (intra- and extraoral) low-level laser therapy (LLLT) and conventional pharmacological modalities in prevention and treatment of oral mucositis (OM) and associated pain and xerostomia in patients with head and neck cancer (HNC) undergoing concurrent chemoradiotherapy (CRT). A prospective comparative randomized study was conducted with 21 patients with head and neck cancer subjected to CRT. Eleven patients received extra- and intraoral LLLT daily from the 1st day until the end of CRT-course before each session during 5 consecutive days, and the other 10 patients received conventional preventive and treatment procedures based on the use of benzidamine 0.15% solution also throughout the duration of CRT, including weekends. OM was measured using an oral toxicity scale (OTS), oral pain was measured using the color-numeric visual analogue scale (VAS), unstimulated salivary flow rate measured by the spitting technique (ml/min), dry mouth symptoms were self-estimated by patients using The Xerostomia Inventory (XI). The LLLT group showed lower mean OTS and VAS scores, lower level of reduction of salivary flow rate during the course of CRT. In both groups, no interruption of CRT was needed. The prophylactic use of both treatments proposed in this study seems to reduce the incidence of severe OM lesions. However, the LLLT was more effective in delaying the appearance of severe OM, oral pain and xerostomia.

  3. Electron beam radiation effects on recycled polyamide-6

    International Nuclear Information System (INIS)

    Evora, Maria Cecilia; Silva, Leonardo G. de Andrade e

    2001-01-01

    Applications of electron beam processing in the treatment of polymers are commonly used. The interaction of high energy radiation with polymers may cause permanent modifications in the polymer's physicochemical structure. The induced modifications may result in degradation of the polymer or in improvement of its properties (crosslinking), which are simultaneous and competing processes, depending on the radiation dose utilized. Crosslinking occurs more readily in the polymer's amorphous content and this process makes the glass transition temperature (Tg) of the polymers to increase. Successive recycling cycles promote changes in polymers properties, such as breaking of structure, molecular weight reduction, melt index increase and mechanical resistance reduction. The polyamide-6 resin was recycled for three successive recycling cycles and thi polyamide-6 specimens were molded by the process of injection molding. These specimens were irradiated at the Nuclear Energetic Research Institute (IPEN) radiation facility, on a JOB 188 model accelerator, with a 1.5 MeV electron beam, doses of 200, 300, 400, 500 and 600 kGy, and dose rate of 22.61 kGy/s. The DMA tests were performed using DMA-983 equipment from TA Instruments and two heatings were adopted in order to eliminate the moisture absorption. The X-ray diffraction analysis wa carried out at the Philips PW 1830 model equipment

  4. The role of parotid gland irradiation in the development of severe hyposalivation (xerostomia) after intensity-modulated radiation therapy for head and neck cancer: Temporal patterns, risk factors, and testing the QUANTEC guidelines.

    Science.gov (United States)

    Owosho, Adepitan A; Thor, Maria; Oh, Jung Hun; Riaz, Nadeem; Tsai, C Jillian; Rosenberg, Haley; Varthis, Spyridon; Yom, Sae Hee K; Huryn, Joseph M; Lee, Nancy Y; Deasy, Joseph O; Estilo, Cherry L

    2017-04-01

    The aims of this study were to investigate temporal patterns and potential risk factors for severe hyposalivation (xerostomia) after intensity-modulated radiotherapy (IMRT) for head and neck cancer (HNC), and to test the two QUANTEC (Quantitative Analysis of Normal Tissue Effects in the Clinic) guidelines. Sixty-three patients treated at the Memorial Sloan Kettering Cancer Center between 2006 and 2015, who had a minimum of three stimulated whole mouth saliva flow measurements (WMSFM) at a median follow-up time of 11 (range: 3-24) months were included. Xerostomia was defined as WMSFM ≤25% compared to relative pre-radiotherapy. Patients were stratified into three follow-up groups: 1: xerostomia was 27%, 14% and 17% at follow-up time points 1, 2 and 3, respectively. At xerostomia (Dmean contra : 25 Gy vs. 15 Gy; Dmean ipsi : 44 Gy vs. 25 Gy). Patients with xerostomia had higher pre-RT WMSFM (3.5 g vs. 2.4 g), and had been treated more frequently with additional chemotherapy (93% vs. 63%; all 4 variables: p xerostomia was higher compared to patients without (26 Gy vs. 20 Gy). The RR as specified by the one- and two-gland QUANTEC guideline was 2.3 and 1.4 for patients with Xerostomia following IMRT peaks within six months post-radiotherapy and fades with time. Limiting the mean dose to both parotid glands (ipsilateral xerostomia. Both QUANTEC guidelines are effective in preventing xerostomia. Copyright © 2017 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  5. Pharmacological activation of the EDA/EDAR signaling pathway restores salivary gland function following radiation-induced damage.

    Directory of Open Access Journals (Sweden)

    Grace Hill

    Full Text Available Radiotherapy of head and neck cancers often results in collateral damage to adjacent salivary glands associated with clinically significant hyposalivation and xerostomia. Due to the reduced capacity of salivary glands to regenerate, hyposalivation is treated by substitution with artificial saliva, rather than through functional restoration of the glands. During embryogenesis, the ectodysplasin/ectodysplasin receptor (EDA/EDAR signaling pathway is a critical element in the development and growth of salivary glands. We have assessed the effects of pharmacological activation of this pathway in a mouse model of radiation-induced salivary gland dysfunction. We report that post-irradiation administration of an EDAR-agonist monoclonal antibody (mAbEDAR1 normalizes function of radiation damaged adult salivary glands as determined by stimulated salivary flow rates. In addition, salivary gland structure and homeostasis is restored to pre-irradiation levels. These results suggest that transient activation of pathways involved in salivary gland development could facilitate regeneration and restoration of function following damage.

  6. Radiation-Induced Second Cancer Risk Estimates From Radionuclide Therapy

    Science.gov (United States)

    Bednarz, Bryan; Besemer, Abigail

    2017-09-01

    The use of radionuclide therapy in the clinical setting is expected to increase significantly over the next decade. There is an important need to understand the radiation-induced second cancer risk associated with these procedures. In this study the radiation-induced cancer risk in five radionuclide therapy patients was investigated. These patients underwent serial SPECT imaging scans following injection as part of a clinical trial testing the efficacy of a 131Iodine-labeled radiopharmaceutical. Using these datasets the committed absorbed doses to multiple sensitive structures were calculated using RAPID, which is a novel Monte Carlo-based 3D dosimetry platform developed for personalized dosimetry. The excess relative risk (ERR) for radiation-induced cancer in these structures was then derived from these dose estimates following the recommendations set forth in the BEIR VII report. The radiation-induced leukemia ERR was highest among all sites considered reaching a maximum value of approximately 4.5. The radiation-induced cancer risk in the kidneys, liver and spleen ranged between 0.3 and 1.3. The lifetime attributable risks (LARs) were also calculated, which ranged from 30 to 1700 cancers per 100,000 persons and were highest for leukemia and the liver for both males and females followed by radiation-induced spleen and kidney cancer. The risks associated with radionuclide therapy are similar to the risk associated with external beam radiation therapy.

  7. Beam diagnostics using transition radiation produced by a 100 Mev electron beam

    International Nuclear Information System (INIS)

    Jablonka, M.; Leroy, J.; Hanus, X.; Derost, J.C.; Wartski, L.

    1991-01-01

    We report on several experiments using the optical transition radiation (OTR) produced by a 100 MeV electron beam. In using a sensitive video camera coupled with a digital image processing system an accurate and simple beam profile monitor has been devised. In measuring with a photo-multiplier the radiation emitted in a small solid angle around the direction of the OTR emission, a signal very sensitive to beam energy variations has been obtained. These experiments have been carried out on the Saclay ALS linac

  8. Design and Selection of Machine Learning Methods Using Radiomics and Dosiomics for Normal Tissue Complication Probability Modeling of Xerostomia.

    Science.gov (United States)

    Gabryś, Hubert S; Buettner, Florian; Sterzing, Florian; Hauswald, Henrik; Bangert, Mark

    2018-01-01

    The purpose of this study is to investigate whether machine learning with dosiomic, radiomic, and demographic features allows for xerostomia risk assessment more precise than normal tissue complication probability (NTCP) models based on the mean radiation dose to parotid glands. A cohort of 153 head-and-neck cancer patients was used to model xerostomia at 0-6 months (early), 6-15 months (late), 15-24 months (long-term), and at any time (a longitudinal model) after radiotherapy. Predictive power of the features was evaluated by the area under the receiver operating characteristic curve (AUC) of univariate logistic regression models. The multivariate NTCP models were tuned and tested with single and nested cross-validation, respectively. We compared predictive performance of seven classification algorithms, six feature selection methods, and ten data cleaning/class balancing techniques using the Friedman test and the Nemenyi post hoc analysis. NTCP models based on the parotid mean dose failed to predict xerostomia (AUCs  0.85), dose gradients in the right-left (AUCs > 0.78), and the anterior-posterior (AUCs > 0.72) direction. Multivariate models of long-term xerostomia were typically based on the parotid volume, the parotid eccentricity, and the dose-volume histogram (DVH) spread with the generalization AUCs ranging from 0.74 to 0.88. On average, support vector machines and extra-trees were the top performing classifiers, whereas the algorithms based on logistic regression were the best choice for feature selection. We found no advantage in using data cleaning or class balancing methods. We demonstrated that incorporation of organ- and dose-shape descriptors is beneficial for xerostomia prediction in highly conformal radiotherapy treatments. Due to strong reliance on patient-specific, dose-independent factors, our results underscore the need for development of personalized data-driven risk profiles for NTCP models of xerostomia. The facilitated

  9. Radiation and shielding around beam absorbers

    International Nuclear Information System (INIS)

    Hurkmans, A.; Maas, R.

    1978-12-01

    During operational conditions it is anticipated that a fair amount of the total available beam power is dumped in either the slit system on one of the beam dumps. Thses beam absorbers therefore become strong radioactive sources. The radiation level due to the absorption of a 100 kW electron beam is estimated and the problem of residual activity is treated. Proposed shielding materials are discussed. (C.F.)

  10. Late xerostomia after intensity-modulated conformational radiotherapy of upper aero-digestive tract cancers: study 2004-03 by the head and neck oncology and radiotherapy Group (Gortec)

    International Nuclear Information System (INIS)

    Toledano, I.; Lapeyre, M.; Graff, P.; Serre, C.; Bensadoun, R.J.; Bensadoun, R.J.; Ortholan, C.; Calais, G.; Alfonsi, M.; Giraud, P.; Racadot, S.

    2010-01-01

    The authors report a retrospective assessment of late xerostomia according to the RTOG (Radiation Therapy Oncology Group) classification of the European Organization for Research and Treatment of Cancer (EORTC) among patients treated by intensity-modulated conformational radiotherapy (IMRT) and suffering from upper aero-digestive tract carcinomas of different stages. Some of these patients have bee operated, and some have been treated by chemotherapy. It appears that the IMRT results in a reduction of late xerostomia, and even in an absence of salivary toxicity. Short communication

  11. Postradiotherapy quality of life for head-and-neck cancer patients is independent of xerostomia

    International Nuclear Information System (INIS)

    Ringash, Jolie; Warde, Padraig; Lockwood, Gina; O'Sullivan, Brian; Waldron, John; Cummings, Bernard

    2005-01-01

    Purpose: To determine the relationship between quality of life (QOL) and xerostomia over time for patients undergoing radiotherapy (RT) for head-and-neck cancer in a prospective clinical trial. Methods and materials: Patients with head-and-neck cancer were randomized to pilocarpine (n = 65) vs. placebo (n = 65) during RT. QOL was measured using the McMaster Head and Neck Radiotherapy Questionnaire (HNRQ). Xerostomia was measured on a linear analog scale. No statistically significant differences were observed between arms; all 130 patients were analyzed together. Results: Baseline QOL data were obtained for 98.5% of participants. The baseline HNRQ score of 5.7 declined significantly to 4.0 (p <0.0001) by RT Week 6 and returned to baseline (5.8) by 6 months after treatment. This represents a large, clinically important change of 1.7 of 7 (24%; effect size 1.34). The decline in HNRQ score during RT paralleled the onset of xerostomia on the linear analog scale (r = 0.36 at 1 month). After treatment, the QOL scores recovered without improvement in xerostomia. The trajectory of the linear analog scale score resembled that of the HNRQ's single xerostomia question (r = 0.75 at 1 month). Conclusion: Quality of life recovers to baseline after RT, despite persistent xerostomia. Either a response shift occurs or xerostomia in the absence of acute mucositis has a relatively small influence on overall QOL

  12. Hyposalivation and xerostomia among Parkinson's disease patients and its impact on quality of life.

    Science.gov (United States)

    Barbe, A G; Heinzler, A; Derman, Shm; Hellmich, M; Timmermann, L; Noack, M J

    2017-05-01

    Parkinson's disease (PD) adversely affects oral health (OH). However, the informative value of xerostomia compared to objective parameters and its impact on quality of life (QoL) are still unclear. This study aimed to explore whether xerostomia correlates with hyposalivation and to define its impact on OH-related QoL. Whole stimulated saliva (WSS) was collected from 30 patients with PD and 30 matched healthy controls. Objective parameters (community periodontal index of treatment needs, plaque/gingivitis index, mucosa situation and cheilitis angularis) and questionnaires (German Oral Health Impact Profile [OHIPG]-14, visual analogue scale [VAS], xerostomia [yes/no] and the Unified Parkinson's Disease Rating Scale-II) were assessed. Eighty-seven per cent of patients with PD showed hyposalivation vs 50% of controls (P = 0.001); 50% of patients with PD reported xerostomia, and none of controls (P xerostomia reported mean VAS values of 4.1 (s.d.: 2.2). WSS did not correlate with VAS values. Half of the patients with PD reported xerostomia and underestimated their xerostomic status, with higher probability than healthy controls. WSS did not reflect the grade of xerostomia. Patients with PD suffered from impaired OH-related QoL. Dental teams should not overlook these oral health risks. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. Radiotherapy-induced xerostomia, pre-clinical promise of LMS-611.

    Science.gov (United States)

    Paterson, Claire; Caldwell, B; Porteous, S; McLean, A; Messow, C M; Thomson, M

    2016-02-01

    Radiotherapy-induced xerostomia (RIX) is the most common permanent side effect of radiotherapy (RT) to the head and neck (H&N). There is no effective topical treatment. LMS-611 is a mimetic of a natural lamellar body which prevents thick secretions like saliva from congesting organs. The primary objective of this study was to assess saliva properties before and during RT to the H&N. The secondary objectives were to re-assess saliva properties with the addition of LMS-611, measure inter-patient variability, correlate patient-reported symptoms with laboratory measurements and design subsequent first-in-human clinical trial of LMS-611. Patients with H&N cancer receiving RT as primary treatment were recruited. Patients completed the Groningen RIX (GRIX) questionnaire and provided saliva samples at baseline and weeks 2, 4 and 6 of RT. Saliva adhesiveness and viscosity were tested by measuring time taken to travel 5 cm down an inclined plane. Thirty patients were enrolled. The inclined plane test (IPT) results (s) were as follows: baseline 31.3, week 2 49.7, week 4 51.1 and week 6 55.7. Wide inter-patient variability was seen at baseline. GRIX scores increased as RT progressed. Spearman rank correlation coefficient of inclined plane tests with GRIX scores was -0.06 at baseline, 0.25 at week 2, 0.12 at week 4 and 0.08 at week 6. LMS-611 concentrations of 10 and 20 mg/ml significantly reduced IPT times on saliva samples. Saliva becomes more visco-adhesive and RIX worsens as RT progresses. There is little correlation between objective and subjective measures of RIX. The addition of LMS-611 to thick, sticky saliva restores its fluidity ex vivo. This warrants in vivo analysis of the effect of LMS-611 upon RIX.

  14. Radiation-induced chondrosarcomas: A case report with review of literature

    Directory of Open Access Journals (Sweden)

    Gupta G

    2010-01-01

    Full Text Available Radiation therapy has become an important component of various cancer treatments. The development of second malignancy as a result of radiation therapy is a well-known sinister complication. However, radiation-induced sarcomas (RIS are rare complications of radiation therapy. The timescale between completion of the radiotherapy and the development of a second malignancy, known as the latent period, can vary widely from as little as 5 years to 50 years later. Radiation-induced sarcomas per se are very rare and those with histomorphology of chondrosarcomas are even rarer. We report a rare case of RIS of left iliac bone in a 62-year-old lady after combined chemotherapy and external beam radiation therapy for cervical carcinoma (stage IIb. This case is being reported for its extreme rarity, vivid histology and clinical presentation.

  15. Fast infrared detectors for beam diagnostics with synchrotron radiation

    International Nuclear Information System (INIS)

    Bocci, A.; Marcelli, A.; Pace, E.; Drago, A.; Piccinini, M.; Cestelli Guidi, M.; De Sio, A.; Sali, D.; Morini, P.; Piotrowski, J.

    2007-01-01

    Beam diagnostic is a fundamental constituent of any particle accelerators either dedicated to high-energy physics or to synchrotron radiation experiments. All storage rings emit radiations. Actually they are high brilliant sources of radiation: the synchrotron radiation emission covers from the infrared range to the X-ray domain with a pulsed structure depending on the temporal characteristics of the stored beam. The time structure of the emitted radiation is extremely useful as a tool to perform time-resolved experiments. However, this radiation can be also used for beam diagnostic to determine the beam stability and to measure the dimensions of the e - or e + beam. Because of the temporal structure of the synchrotron radiation to perform diagnostic, we need very fast detectors. Indeed, the detectors required for the diagnostics of the stored particle bunches at third generation synchrotron radiation sources and FEL need response times in the sub-ns and even ps range. To resolve the bunch length and detect bunch instabilities, X-ray and visible photon detectors may be used achieving response times of a few picoseconds. Recently, photon uncooled infrared devices optimized for the mid-IR range realized with HgCdTe semiconductors allowed to obtain sub-nanosecond response times. These devices can be used for fast detection of intense IRSR sources and for beam diagnostic. We present here preliminary experimental data of the pulsed synchrotron radiation emission of DAΦNE, the electron positron collider of the LNF laboratory of the INFN, performed with new uncooled IR detectors with a time resolution of a few hundreds of picoseconds

  16. A clinical evaluation denture adhesives used by patients with xerostomia.

    Science.gov (United States)

    Bogucki, Zdzislaw A; Napadlek, Piotr; Dabrowa, Tomasz

    2015-02-01

    The purpose of study was to analyze the participants' opinions concerning the effectiveness of 6 denture adhesives (DA). The study group included 60 participants. Criteria for selecting the patients were as follows: reduced retention and stabilization of maxillary complete dentures and xerostomia. These features were evaluated on basis of clinical examination and standard sialometry tests (u-SFR). Retention of maxillary dentures was scored by modified Kapur index before application of DA. All participants were divided randomly into 6 groups regarding the use of the 6 DA during a 6-month period. After this time, participants completed an HRQL questionnaire. DA noticeably improved retention and stabilization of maxillary complete dentures. DA in the glue form had the best retention effectiveness in participants with xerostomia. These materials are difficult to clean from the denture base. The data are presented in tables and figures. The results of the study collected positive influence of adhesives on retention of dentures in xerostomia patients. The cleaning dentures and denture bearing tissues was difficult. DA help in the use of prostheses, but it is also necessary for the treatment of the causes and symptoms of xerostomia.

  17. BRIEF OVERVIEW OF XEROSTOMIA PROBLEM

    Directory of Open Access Journals (Sweden)

    S. O. Podvyaznikov

    2015-01-01

    Full Text Available The saliva is indispensable for preservation of healthy mouth and teeth, due to its composition and physical and chemical properties. Saliva preserves the teeth and favors their remineralization for account of afflux of irreplaceable minerals: calcium and phosphor. Due to contents of such epidermal growth factor it participates in tissue repair. The saliva contains the antibacterial, antiviral and antifungal drug resistance factors, suppressing the bacterial colonization of teeth and mucosa.Dry mouth (xerostomia results in development of stomatitis, periodontitis effects, increases a risk of infectious lesions of oral mucosa. The severest forms of such pathology (Degrees II–III are observed in the patients administered of X-ray therapy on head and neck area and in case of Sjogren’s syndrome, when the irreversible degenerative changes develop in эпителии salivary glands epithelium. Etiology and pathogenesis of xerostomia are not exhaustively studied yet, and treatment of such complex pathology is still symptomatic.

  18. Treatment planning constraints to avoid xerostomia in head and neck radiotherapy: an independent test of QUANTEC criteria using a prospectively collected dataset

    Science.gov (United States)

    Moiseenko, Vitali; Wu, Jonn; Hovan, Allan; Saleh, Ziad; Apte, Aditya; Deasy, Joseph O.; Harrow, Stephen; Rabuka, Carman; Muggli, Adam; Thompson, Anna

    2011-01-01

    Purpose The severe reduction of salivary function (xerostomia) is a common complication following radiation therapy for head and neck cancer. Consequently, guidelines to ensure adequate function based on parotid gland tolerance dose-volume parameters have been suggested by the QUANTEC group (1) and by Ortholan et al. (2). We perform a validation test of these guidelines against a prospectively collected dataset and compared to a previously published dataset. Method and Materials Whole-mouth stimulated salivary flow data from 66 head and neck cancer patients treated with radiotherapy at the British Columbia Cancer Agency (BCCA) were measured, and treatment planning data were abstracted. Flow measurements were collected from 50 patients at 3 months, and 60 patients at 12 month follow-up. Previously published data from a second institution (WUSTL) were used for comparison. A logistic model was used to describe the incidence of grade 4 xerostomia as a function of the mean dose of the spared parotid gland. The rate of correctly predicting the lack of xerostomia (negative predictive value, NPV) was computed for both the QUANTEC constraints and Ortholan et al. (2) recommendation to constrain the total volume of both glands receiving more than 40 Gy to less than 33%. Results Both data sets showed a rate of xerostomia xerostomia at 12 months after therapy, based on the least-irradiated gland, were D50=32.4 Gy and and γ=0.97. NPVs for QUANTEC guideline were 94% (BCCA data), 90% (WUSTL data). For Ortholan et al. (2) guideline NPVs were 85% (BCCA), and 86% (WUSTL). Conclusion This confirms that the QUANTEC guideline effectively avoids xerostomia, and this is somewhat more effective than constraints on the volume receiving more than 40 Gy. PMID:21640505

  19. Spin-polarized free electron beam interaction with radiation and superradiant spin-flip radiative emission

    Directory of Open Access Journals (Sweden)

    A. Gover

    2006-06-01

    Full Text Available The problems of spin-polarized free-electron beam interaction with electromagnetic wave at electron-spin resonance conditions in a magnetic field and of superradiant spin-flip radiative emission are analyzed in the framework of a comprehensive classical model. The spontaneous emission of spin-flip radiation from electron beams is very weak. We show that the detectivity of electron spin resonant spin-flip and combined spin-flip/cyclotron-resonance-emission radiation can be substantially enhanced by operating with ultrashort spin-polarized electron beam bunches under conditions of superradiant (coherent emission. The proposed radiative spin-state modulation and the spin-flip radiative emission schemes can be used for control and noninvasive diagnostics of polarized electron/positron beams. Such schemes are of relevance in important scattering experiments off nucleons in nuclear physics and off magnetic targets in condensed matter physics.

  20. Dosimetric Predictors of Patient-Reported Xerostomia and Dysphagia With Deintensified Chemoradiation Therapy for HPV-Associated Oropharyngeal Squamous Cell Carcinoma.

    Science.gov (United States)

    Chera, Bhishamjit S; Fried, David; Price, Alex; Amdur, Robert J; Mendenhall, William; Lu, Chiray; Das, Shiva; Sheets, Nathan; Marks, Lawrence; Mavroidis, Panayiotis

    2017-08-01

    To estimate the association between different dose-volume metrics of the salivary glands and pharyngeal constrictors with patient reported severity of xerostomia/dysphagia in the setting of deintensified chemoradiation therapy (CRT). Forty-five patients were treated on a phase 2 study assessing the efficacy of deintensified CRT for favorable-risk, HPV-associated oropharyngeal squamous cell carcinoma. Patients received 60 Gy intensity modulated radiation therapy with concurrent weekly cisplatin (30 mg/m 2 ), and reported the severity of their xerostomia/dysphagia (before and after treatment) using the patient-reported outcome version of the Common Terminology Criteria for Adverse Events (CTCAE) (PRO-CTCAE). Individual patient dosimetric data of the contralateral parotid and submandibular glands and pharyngeal constrictors were correlated with changes in PRO-CTCAE severity. A change in severity (from baseline) of ≥2 was considered clinically meaningful. Associations between dose-volume metrics and patient outcomes were assessed with receiver operating characteristic (ROC) curve and logistic regression model. Six months after CRT, patients reporting xerostomia severity (n=14) had an average D mean = 22 ± 9 Gy to the sum of the contralateral glands (parotid + submandibular) compared with the patients reporting ≥2 change (n=21), who had an average D mean = 34 ± 8 Gy. V15 to V55 for the combined contralateral glands showed the strongest association with xerostomia (area under the curve [AUC] = 0.83-0.86). Based on the regression analysis, a 20% risk of toxicity was associated with V15 = 48%, V25 = 30%, and D mean =21 Gy. Six months after CRT, patients reporting xerostomia/dysphagia appears to be associated with the V15 of the combined contralateral salivary glands and V55 to V60 of the superior pharyngeal constrictors. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Ultra-High Density Electron Beams for Beam Radiation and Beam Plasma Interaction

    CERN Document Server

    Anderson, Scott; Frigola, Pedro; Gibson, David J; Hartemann, Fred V; Jacob, Jeremy S; Lim, Jae; Musumeci, Pietro; Rosenzweig, James E; Travish, Gil; Tremaine, Aaron M

    2005-01-01

    Current and future applications of high brightness electron beams, which include advanced accelerators such as the plasma wake-field accelerator (PWFA) and beam-radiation interactions such as inverse-Compton scattering (ICS), require both transverse and longitudinal beam sizes on the order of tens of microns. Ultra-high density beams may be produced at moderate energy (50 MeV) by compression and subsequent strong focusing of low emittance, photoinjector sources. We describe the implementation of this method used at LLNL's PLEIADES ICS x-ray source in which the photoinjector-generated beam has been compressed to 300 fsec duration using the velocity bunching technique and focused to 20 μm rms size using an extremely high gradient, permanent magnet quadrupole (PMQ) focusing system.

  2. Ixeris dentata extract regulates salivary secretion through the activation of aquaporin-5 and prevents diabetes-induced xerostomia.

    Science.gov (United States)

    Bhattarai, Kashi Raj; Lee, Sang-Won; Kim, Seung Hyun; Kim, Hyung-Ryong; Chae, Han-Jung

    2017-01-01

    The aim of this study was to investigate the effects of Ixeris dentata (IXD) extract to improve the salivation rate in dry mouth induced by diabetes. Both control and diabetic rats were treated with a sublingual spray of either water or IXD extract to determine the effects of IXD on salivation. During the study, we observed that IXD extract treatment increased the salivary flow rate in diabetic rats. The expression of α-amylase was increased significantly in both saliva and glandular tissue lysates of IXD-treated diabetic rats. Aquaporin-5 protein expression was abnormally low in the salivary glands of diabetic rats, which increased hyposalivation and led to salivary dysfunction. However, a single oral spray of IXD extract drastically increased the expression of aquaporin-5 in salivary gland acinar and ductal cells in diabetic rats. Moreover, IXD extract induced expression of Na + /H + exchangers in the salivary gland, which suggests that Na + /H + exchangers modulate salivary secretions and aid in the fluid-secretion mechanism. Furthermore, transient treatment with IXD extract increased the intracellular calcium in human salivary gland cells. Taken together, these results suggest the potential value of an IXD extract for the treatment of diabetes-induced hyposalivation and xerostomia.

  3. Frequency of burning mouth and subjective xerostomia in patients with diabetes mellitus type 2

    Directory of Open Access Journals (Sweden)

    M. Salehi

    2017-12-01

    Full Text Available Background: Diabetes mellitus is a common chronic metabolic disease which have numerous physical effects for patients. Objective: The aim of this study was to determine the prevalence of subjective xerostomia and burning mouth of patients with type 2 diabetes mellitus in cities of Sari and Qaemshahr. Methods: In this descriptive-analytic study, totally 1455 patients with type 2 diabetes mellitus with complain of xerostomia and/or burning mouth which had referred to diabetes clinic in Sari and Qaemshahr were examined in 2016. For every patient asked about chronic xerostomia and burning mouth and if the answer was positive, the oral examination was done to ensure the absence of mucosal lesions and find signs of xerostomia. Then, xerostomia questionnaire was completed by patients suffering from dry mouth. Finally, the information was statistically analyzed by T test and chi square test. Findings: Prevalence of burning mouth was found 111 (7.6% in diabetic patients that in the women were significantly higher than in men (P<0.0001. Prevalence of xerstomia patients was found 239 (16.4% that was not significant between the male and female. There was a significant correlation between burning mouth and xerostomia with FBS and HbA1c in diabetic patients (P<0.0001. Conclusion: Possibility of burning mouth, and xerostomia will increase in the diabetic patients with low metabolic control which can cause more severe side effects related to oral health.

  4. Design and development of radiation absorber for sighting beam line

    International Nuclear Information System (INIS)

    Sridhar, R.; Shukla, S.K.

    2005-01-01

    During the commissioning of Indus-2 , it is necessary to view the synchrotron radiation that will be emanating from the dipole exit ports. The 10 0 beam line from dipole 11 was earmarked for sighting beam line. The synchrotron radiation power density would be around 340 watts on the photon absorber inside the radiation absorber module, at the specified beam power of Indus-2. The beam striking on this photon absorber produces x-rays and Bremsstrahlung radiation. These are to be stopped and absorbed by radiation absorber. The photon absorber and the radiation absorber are integrated in a single vacuum chamber and actuated by a pneumatic cylinder connected using a bellow. Radiation absorber was needed to isolate the diagnostic components and to protect them from radiation a well as heat when they were not in use. The paper describes the design, calculation and development of the dynamic photon cum radiation absorber. The ultimate vacuum performance is also described. (author)

  5. Radiation dermatitis following electron beam therapy

    International Nuclear Information System (INIS)

    Price, N.M.

    1978-01-01

    Ten patients, who had been treated for mycosis fungoides with electron beam radiation ten or more years previously, were examined for signs of radiation dermatitis. Although most patients had had acute radiation dermatitis, only a few manifested signs of mild chronic changes after having received between 1,000 and 2,800 rads

  6. Coherent electromagnetic radiation of a combined electron-ion beam

    Energy Technology Data Exchange (ETDEWEB)

    Pankratov, S G; Samoshenkov, Yu K [Vsesoyuznyj Nauchno-Issledovatel' skij Inst. Optiko-Fizicheskikh Izmerenij, Moscow (USSR)

    1977-07-01

    The intensity of coherent electromagnetic radiation due to interaction of a modulated electron beam with a modulated ion beam is calculated. It is shown that the radiation intensity has a sharp maximum at the frequency equal to the difference of the modulation frequency of the electron and ion beams. The results obtained are compared with those corresponding to the scattering of a modulated electron beam on randomly distributed gas ions.

  7. Numerical Simulations for the Beam-Induced Electron Cloud in the LHC Beam Screen

    CERN Document Server

    Brüning, Oliver Sim

    1998-01-01

    The following work summarises simulation results obtained at CERN for the beam-induced electron cloud and looks at possible cures for the heat load in the LHC beam screen. The synchrotron radiation in the LHC creates a continuous flow of photoelectrons. These electrons are accelerated by the electric field of the bunch and hit the vacuum chamber on the opposite side of the beam pipe where they crea te secondary electrons which are again accelerated by the next bunch. For a large secondary emission yield the above mechanism leads to an exponential growth of the electron cloud which is limited by space charge forces. The simulations use a two-dimensional mesh for the space charge calculations and include the effect of image charges on the vacuum chamber wall. Depending on the quantum yield for the production of photoelectrons, the secondary emission yield and the reflectivity, the heat load can vary from 0.1 W/m to more than 15 W/m.

  8. An adaptive crystal bender for high power synchrotron radiation beams

    International Nuclear Information System (INIS)

    Berman, L.E.; Hastings, J.B.

    1992-01-01

    Perfect crystal monochromators cannot diffract x-rays efficiently, nor transmit the high source brightness available at synchrotron radiation facilities, unless surface strains within the beam footprint are maintained within a few arcseconds. Insertion devices at existing synchrotron sources already produce x-ray power density levels that can induce surface slope errors of several arcseconds on silicon monochromator crystals at room temperature, no matter how well the crystal is cooled. The power density levels that will be produced by insertion devices at the third-generation sources will be as much as a factor of 100 higher still. One method of restoring ideal x-ray diffraction behavior, while coping with high power levels, involves adaptive compensation of the induced thermal strain field. The design and performance, using the X25 hybrid wiggler beam line at the National Synchrotron Light Source (NSLS), of a silicon crystal bender constructed for this purpose are described

  9. Impact of large beam-induced heat loads on the transient operation of the beam screens and the cryogenic plants of the Future Circular Collider (FCC)

    Science.gov (United States)

    Correia Rodrigues, H.; Tavian, L.

    2017-12-01

    The Future Circular Collider (FCC) under study at CERN will produce 50-TeV high-energy proton beams. The high-energy particle beams are bent by 16-T superconducting dipole magnets operating at 1.9 K and distributed over a circumference of 80 km. The circulating beams induce 5 MW of dynamic heat loads by several processes such as synchrotron radiation, resistive dissipation of beam image currents and electron clouds. These beam-induced heat loads will be intercepted by beam screens operating between 40 and 60 K and induce transients during beam injection. Energy ramp-up and beam dumping on the distributed beam-screen cooling loops, the sector cryogenic plants and the dedicated circulators. Based on the current baseline parameters, numerical simulations of the fluid flow in the cryogenic distribution system during a beam operation cycle were performed. The effects of the thermal inertia of the headers on the helium flow temperature at the cryogenic plant inlet as well as the temperature gradient experienced by the beam screen has been assessed. Additionally, this work enabled a thorough exergetic analysis of different cryogenic plant configurations and laid the building-block for establishing design specification of cold and warm circulators.

  10. Auricular Acupressure Helps Alleviate Xerostomia in Maintenance Hemodialysis Patients: A Pilot Study.

    Science.gov (United States)

    Yang, Guowen; Lin, Shaoqin; Wu, Yuchi; Zhang, Shangpeng; Wu, Xiuqing; Liu, Xusheng; Zou, Chuan; Lin, Qizhan

    2017-04-01

    Xerostomia is one of the most common complaints in maintenance hemodialysis (MHD) patients. This problem contributes to excess fluid intake and results in poor survival outcome. Based on Traditional Chinese Medicine (TCM) theory and literature studies, the authors have been practicing auricular acupressure therapy (AAT) to help patients with xerostomia. This pilot study was conducted to demonstrate the potential of AAT for xerostomia in MHD patients. Eligible subjects who agreed to participate in this study were recruited and provided with AAT for 4 weeks. The Summated Xerostomia Inventory (SXI), as well as measurement of inter-dialytic weight gain (IDWG), daily inter-dialytic weight gain (daily IDWG), percentage of inter-dialytic weight gain (IDWG%), blood pressure, and biochemical parameters, were completed at baseline and after a 4-week intervention. A total of 26 eligible participants were recruited. Of them, 10 men and 16 women (M age  = 52.92 ± 11.80 years; dialysis vintage 81.86 ± 46.05 months) completed the study. After the 4-week AAT intervention, the SXI scores were significantly decreased compared with baseline (from 10.08 ± 2.26 to 9.04 ± 2.14; p xerostomia intensity for MHD patients.

  11. Does radiation dose to the salivary glands and oral cavity predict patient-rated xerostomia and sticky saliva in head and neck cancer patients treated with curative radiotherapy?

    International Nuclear Information System (INIS)

    Jellema, Anke Petra; Doornaert, Patricia; Slotman, Ben J.; Rene Leemans, C.; Langendijk, Johannes A.

    2005-01-01

    Background and Purpose: To investigate the association between the mean salivary gland and oral cavity dose, with patient-rated moderate and severe xerostomia and sticky saliva. Patients and methods: One hundred and fifty-seven patients treated with bilateral irradiation for head and neck cancer were included. The parotid and submandibular glands and the oral cavity were delineated on plannings-CT scans. At baseline and 6 and 12 months self-reported xerostomia and sticky saliva were assessed using the EORTC QLQ-H and N35 questionnaire. Results: At 6 months a significant association between the mean parotid (MD par ) and mean submandibular dose (MD subm ) and xerostomia was observed (OR-MD par : 1.17; P=0.002 and OR-MD subm : 1.08; P=0.02). Between MD par and MD subm , a significant interaction term was present. No significant association was found with the oral cavity dose. Xerostomia was reversible depending on MD par and MD subm . Considering Sticky saliva, a significant association was found at 6 and 12 months with MD subm (OR: 1.03; P par and MD subm influence the risk of xerostomia in irradiated patients at 6 months. This probability as a function of the mean parotid dose significantly depended on the mean dose in the submandibular glands. Sticky saliva mainly depends on MD subm

  12. Comprehensive MRI simulation methodology using a dedicated MRI scanner in radiation oncology for external beam radiation treatment planning

    International Nuclear Information System (INIS)

    Paulson, Eric S.; Erickson, Beth; Schultz, Chris; Allen Li, X.

    2015-01-01

    Purpose: The use of magnetic resonance imaging (MRI) in radiation oncology is expanding rapidly, and more clinics are integrating MRI into their radiation therapy workflows. However, radiation therapy presents a new set of challenges and places additional constraints on MRI compared to diagnostic radiology that, if not properly addressed, can undermine the advantages MRI offers for radiation treatment planning (RTP). The authors introduce here strategies to manage several challenges of using MRI for virtual simulation in external beam RTP. Methods: A total of 810 clinical MRI simulation exams were performed using a dedicated MRI scanner for external beam RTP of brain, breast, cervix, head and neck, liver, pancreas, prostate, and sarcoma cancers. Patients were imaged in treatment position using MRI-optimal immobilization devices. Radiofrequency (RF) coil configurations and scan protocols were optimized based on RTP constraints. Off-resonance and gradient nonlinearity-induced geometric distortions were minimized or corrected prior to using images for RTP. A multidisciplinary MRI simulation guide, along with window width and level presets, was created to standardize use of MR images during RTP. A quality assurance program was implemented to maintain accuracy and repeatability of MRI simulation exams. Results: The combination of a large bore scanner, high field strength, and circumferentially wrapped, flexible phased array RF receive coils permitted acquisition of thin slice images with high contrast-to-noise ratio (CNR) and image intensity uniformity, while simultaneously accommodating patient setup and immobilization devices. Postprocessing corrections and alternative acquisition methods were required to reduce or correct off-resonance and gradient nonlinearity induced geometric distortions. Conclusions: The methodology described herein contains practical strategies the authors have implemented through lessons learned performing clinical MRI simulation exams. In

  13. Comprehensive MRI simulation methodology using a dedicated MRI scanner in radiation oncology for external beam radiation treatment planning

    Energy Technology Data Exchange (ETDEWEB)

    Paulson, Eric S., E-mail: epaulson@mcw.edu [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, Wisconsin 53226 and Department of Radiology, Medical College of Wisconsin, Milwaukee, Wisconsin 53226 (United States); Erickson, Beth; Schultz, Chris; Allen Li, X. [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, Wisconsin 53226 (United States)

    2015-01-15

    Purpose: The use of magnetic resonance imaging (MRI) in radiation oncology is expanding rapidly, and more clinics are integrating MRI into their radiation therapy workflows. However, radiation therapy presents a new set of challenges and places additional constraints on MRI compared to diagnostic radiology that, if not properly addressed, can undermine the advantages MRI offers for radiation treatment planning (RTP). The authors introduce here strategies to manage several challenges of using MRI for virtual simulation in external beam RTP. Methods: A total of 810 clinical MRI simulation exams were performed using a dedicated MRI scanner for external beam RTP of brain, breast, cervix, head and neck, liver, pancreas, prostate, and sarcoma cancers. Patients were imaged in treatment position using MRI-optimal immobilization devices. Radiofrequency (RF) coil configurations and scan protocols were optimized based on RTP constraints. Off-resonance and gradient nonlinearity-induced geometric distortions were minimized or corrected prior to using images for RTP. A multidisciplinary MRI simulation guide, along with window width and level presets, was created to standardize use of MR images during RTP. A quality assurance program was implemented to maintain accuracy and repeatability of MRI simulation exams. Results: The combination of a large bore scanner, high field strength, and circumferentially wrapped, flexible phased array RF receive coils permitted acquisition of thin slice images with high contrast-to-noise ratio (CNR) and image intensity uniformity, while simultaneously accommodating patient setup and immobilization devices. Postprocessing corrections and alternative acquisition methods were required to reduce or correct off-resonance and gradient nonlinearity induced geometric distortions. Conclusions: The methodology described herein contains practical strategies the authors have implemented through lessons learned performing clinical MRI simulation exams. In

  14. Radiation-induced myocardial perfusion abnormalities in breast cancer patients following external beam radiation therapy.

    Science.gov (United States)

    Eftekhari, Mohammad; Anbiaei, Robabeh; Zamani, Hanie; Fallahi, Babak; Beiki, Davood; Ameri, Ahmad; Emami-Ardekani, Alireza; Fard-Esfahani, Armaghan; Gholamrezanezhad, Ali; Seid Ratki, Kazem Razavi; Roknabadi, Alireza Momen

    2015-01-01

    Radiation therapy for breast cancer can induce myocardial capillary injury and increase cardiovascular morbidity and mortality. A prospective cohort was conducted to study the prevalence of myocardial perfusion abnormalities following radiation therapy of left-sided breast cancer patients as compared to those with right-sided cancer. To minimize potential confounding factors, only those patients with low 10-year risk of coronary artery disease (based on Framingham risk scoring) were included. All patients were initially treated by modified radical mastectomy and then were managed by postoperative 3D Conformal Radiation Therapy (CRT) to the surgical bed with an additional 1-cm margin, delivered by 46-50 Gy (in 2 Gy daily fractions) over a 5-week course. The same dose-adjusted chemotherapy regimen (including anthracyclines, cyclophosphamide and taxol) was given to all patients. Six months after radiation therapy, all patients underwent cardiac SPECT for the evaluation of myocardial perfusion. A total of 71 patients with a mean age of 45.3±7.2 years [35 patients with leftsided breast cancer (exposed) and 36 patients with right-sided cancer (controls)] were enrolled. Dose-volume histogram (DVH) [showing the percentage of the heart exposed to >50% of radiation] was significantly higher in patients with left-sided breast cancer. Visual interpretation detected perfusion abnormalities in 42.9% of cases and 16.7% of controls (P=0.02, Odds ratio=1.46). In semiquantitative segmental analysis, only apical (28.6% versus 8.3%, P=0.03) and anterolateral (17.1% versus 2.8%, P=0.049) walls showed significantly reduced myocardial perfusion in the exposed group. Summed Stress Score (SSS) of>3 was observed in twelve cases (34.3%), while in five of the controls (13.9%),(Odds ratio=1.3). There was no significant difference between the groups regarding left ventricular ejection fraction. The risk of radiation induced myocardial perfusion abnormality in patients treated with CRT on the

  15. Sparing bilateral neck level IB in oropharyngeal carcinoma and xerostomia outcomes.

    Science.gov (United States)

    Tam, Moses; Riaz, Nadeem; Kannarunimit, Danita; Peña, Angela P; Schupak, Karen D; Gelblum, Daphna Y; Wolden, Suzanne L; Rao, Shyam; Lee, Nancy Y

    2015-08-01

    To assess whether sparing neck-level IB in target delineation of node-positive (N+) oropharyngeal carcinoma (OPC) can improve xerostomia outcomes without compromising locoregional control (LRC). A total of 125 N+ OPC patients with a median age of 57 years underwent chemoradiation between May 2010 and December 2011. A total of 74% of patients had T1-T2 disease, 26% T3-T4, 16% N1, 8% N2A, 48% N2B, 28% N2C; 53% base of tongue, 41% tonsil, and 6% other. Patients were divided into those who had target delineation sparing of bilateral level IB (the spared cohort) versus no sparing (the treated cohort). Sparing of contralateral high-level II nodes was also performed more consistently in the spared cohort. A prospective xerostomia questionnaire (patient reported) was given at each patient follow-up visit to this cohort of patients to assess late xerostomia. Clinical assessment (observer rated) at each patient follow-up visit was also recorded. The 2-year LRC for the spared and treated cohorts was 97.5% and 93.8%, respectively (median follow-up, 23.2 mo). No locoregional failures occurred outside of treatment fields. The spared cohort experienced significant benefits in patient-reported xerostomia summary scores (P=0.021) and observer-rated xerostomia scores (P=0.006). In addition, there were significant reductions in mean doses to the ipsilateral submandibular gland (63.9 vs. 70.5 Gy; Pxerostomia outcomes.

  16. Theory for beam-plasma millimeter-wave radiation source experiments

    International Nuclear Information System (INIS)

    Rosenberg, M.; Krall, N.A.

    1989-01-01

    This paper reports on theoretical studies for millimeter-wave plasma source experiments. In the device, millimeter-wave radiation is generated in a plasma-filled waveguide driven by counter-streaming electron beams. The beams excite electron plasma waves which couple to produce radiation at twice the plasma frequency. Physics topics relevant to the high electron beam current regime are discussed

  17. Influence of xerostomia on oral health-related quality of life in the elderly: a 5-year longitudinal study.

    Science.gov (United States)

    Enoki, Kaori; Matsuda, Ken-Ich; Ikebe, Kazunori; Murai, Shunsuke; Yoshida, Minoru; Maeda, Yoshinobu; Thomson, William Murray

    2014-06-01

    Xerostomia and tooth loss are major oral health problems in the elderly. The aim of this longitudinal study was to characterize the influence of xerostomia on oral health-related quality of life (OHRQoL) among elderly Japanese people. A total of 99 community-dwelling, independently living individuals aged 60 years and older were interviewed and underwent dental examination at baseline and at a 5-year follow-up. The Oral Health Impact Profile-14 and the Xerostomia Inventory were used to assess OHRQoL and xerostomia severity, respectively. Participants whose xerostomia worsened over the 5-year period had a significantly poorer follow-up OHRQoL. Linear regression models showed that tooth loss and worsening xerostomia were significant predictors of poorer follow-up OHRQoL. Tooth loss and worsening xerostomia result in poorer OHRQoL among older Japanese people. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. Radiation therapy apparatus having retractable beam stopper

    International Nuclear Information System (INIS)

    Coad, G.L.

    1983-01-01

    This invention relates to a radiation therapy apparatus which utilized a linear translation mechanism for positioning a beam stopper. An apparatus is described wherein the beam stopper is pivotally attached to the therapy machine with an associated drive motor in such a way that the beam stopper retracts linearly

  19. The evaluation of properties for radiation therapy techniques with flattening filter-free beam and usefulness of time and economy to a patient with the radiation therapy

    International Nuclear Information System (INIS)

    Goo, Jang Hyeon; Won, Hui Su; Hong, Joo Wan; Chang, Nam Jun; Park, Jin Hong

    2014-01-01

    The aim of this study was to appraise properties for radiation therapy techniques and effectiveness of time and economy to a patient in the case of applying flattening filter-free (3F) and flattening filter (2F) beam to the radiation therapy. Alderson rando phantom was scanned for computed tomography image. Treatment plans for intensity modulated radiation therapy (IMRT), volumetric modulated arc therapy (VMAT) and stereotactic body radiation therapy (SBRT) with 3F and 2F beam were designed for prostate cancer. To evaluate the differences between the 3F and 2F beam, total monitor units (MUs), beam on time (BOT) and gantry rotation time (GRT) were used and measured with TrueBeam TM STx and Surveillance And Measurement (SAM) 940 detector was used for photoneutron emitted by using 3F and 2F. To assess temporal and economical aspect for a patient, total treatment periods and medical fees were estimated. In using 3F beam, total MUs in IMRT plan increased the highest up to 34.0% and in the test of BOT, GRT and photoneutron, the values in SBRT plan decreased the lowest 39.8, 38.6 and 48.1%, respectively. In the temporal and economical aspect, there were no differences between 3F and 2F beam in all of plans and the results showed that 10 days and 169,560 won was lowest in SBRT plan. According as the results, total MUs increased by using 3F beam than 2F beam but BOT, GRT and photoneutron decreased. From above the results, using 3F beam can decrease intra-fraction setup error and risk of radiation-induced secondary malignancy. But, using 3F beam did not make the benefits of temporal and economical aspect for a patient with the radiation therapy

  20. The evaluation of properties for radiation therapy techniques with flattening filter-free beam and usefulness of time and economy to a patient with the radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Goo, Jang Hyeon; Won, Hui Su; Hong, Joo Wan; Chang, Nam Jun; Park, Jin Hong [Dept. of Radiation Oncology, Seoul national university Bundang hospital, Sungnam (Korea, Republic of)

    2014-12-15

    The aim of this study was to appraise properties for radiation therapy techniques and effectiveness of time and economy to a patient in the case of applying flattening filter-free (3F) and flattening filter (2F) beam to the radiation therapy. Alderson rando phantom was scanned for computed tomography image. Treatment plans for intensity modulated radiation therapy (IMRT), volumetric modulated arc therapy (VMAT) and stereotactic body radiation therapy (SBRT) with 3F and 2F beam were designed for prostate cancer. To evaluate the differences between the 3F and 2F beam, total monitor units (MUs), beam on time (BOT) and gantry rotation time (GRT) were used and measured with TrueBeam{sup TM} STx and Surveillance And Measurement (SAM) 940 detector was used for photoneutron emitted by using 3F and 2F. To assess temporal and economical aspect for a patient, total treatment periods and medical fees were estimated. In using 3F beam, total MUs in IMRT plan increased the highest up to 34.0% and in the test of BOT, GRT and photoneutron, the values in SBRT plan decreased the lowest 39.8, 38.6 and 48.1%, respectively. In the temporal and economical aspect, there were no differences between 3F and 2F beam in all of plans and the results showed that 10 days and 169,560 won was lowest in SBRT plan. According as the results, total MUs increased by using 3F beam than 2F beam but BOT, GRT and photoneutron decreased. From above the results, using 3F beam can decrease intra-fraction setup error and risk of radiation-induced secondary malignancy. But, using 3F beam did not make the benefits of temporal and economical aspect for a patient with the radiation therapy.

  1. An Evidence-Based Review Literature About Risk Indicators and Management of Unknown-Origin Xerostomia

    Directory of Open Access Journals (Sweden)

    Farzaneh Agha-hosseini

    2013-01-01

    Full Text Available Objective: This evidence-based article reviews risk indicators and management of unknown-origin xerostomia. Xerostomia and hyposalivation refer to different aspects of dry mouth. Xerostomia is a subjective sensation of dry mouth, whilst hyposalivation is defined as an objective assessment of reduced salivary flow rate. About 30% of the elderly (65 years and older experience xerostomia and hyposalivation. Structural and functional factors, or both may lead to salivary gland dysfunction.Study Selection: The EBM literature search was conducted by using the medical literature database MEDLINE via PubMed and OvidMedline search engines. Results were limited to English language articles (1965 to present including clinical trials (CT, randomized controlled trials (RCT, systematic reviews and review articles. Case control or cohort studies were included for the etiology.Results: Neuropathic etiology such as localized oral alteration of thermal sensations, saliva composition change (for example higher levels of K, Cl, Ca, IgA, amylase, calcium, PTH and cortisol, lower levels of estrogen and progesterone, smaller salivary gland size, and illnesses such as lichen planus, are risk indicators for unknown-origin xerostomia. The management is palliative and preventative. Management of symptoms includes drug administration (systemic secretogogues, saliva substitutes and bile secretion-stimulator, night guard, diet and habit modifications. Other managements may be indicated to treat adverse effects.Conclusion: Neuropathic etiology, saliva composition change, smaller salivary gland size, and illnesses such as oral lichen planus can be suggestive causes for unknown-origin xerostomia. However, longitudinal studies will be important to elucidate the causes of unknown-origin xerostomia.

  2. Caffeine Markedly Enhanced Radiation-Induced Bystander Effects

    International Nuclear Information System (INIS)

    Jiang Erkang; Wu Lijun

    2009-01-01

    In this paper it is shown that incubation with 2 mM caffeine enhanced significantly the MN (micronucleus) formation in both the 1 cGy α-particle irradiated and non-irradiated bystander regions. Moreover, caffeine treatment made the non-irradiated bystander cells more sensitive to damage signals. Treated by c-PTIO(2-(4-carboxy-phenyl)- 4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide), a nitric oxide (NO) scavenger, the MN frequencies were effectively inhibited, showing that nitric oxide might be very important in mediating the enhanced damage. These results indicated that caffeine enhanced the low dose α-particle radiation-induced damage in irradiated and non-irradiated bystander regions, and therefore it is important to investigate the relationship between the radiosensitizer and radiation-induced bystander effects (RIBE). (ion beam bioengineering)

  3. Reducing Xerostomia After Chemo-IMRT for Head and Neck Cancer: Beyond Sparing the Parotid Glands

    Science.gov (United States)

    Little, Michael; Schipper, Matthew; Feng, Felix Y.; Vineberg, Karen; Cornwall, Craig; Murdoch-Kinch, Carol-Anne; Eisbruch, Avraham

    2011-01-01

    Purpose To assess whether in addition to sparing parotid glands (PGs), xerostomia after chemo-IMRT of head and neck cancer is affected by reducing doses to other salivary glands. Methods Prospective study: 78 patients with stages III/IV oropharynx/nasopharynx cancers received chemo-IMRT aiming to spare the parts outside the targets of bilateral PGs, oral cavity (OC) containing the minor salivary glands, and contralateral submandibular gland (SMG) (when contralateral level I was not a target). Pretherapy and periodically through 24 months, validated patient-reported xerostomia questionnaires (XQ) scores and observer-graded xerostomia were recorded, and stimulated and unstimulated saliva measured selectively from each of the PGs and SMGs. Mean OC doses served as surrogates of minor salivary glands dysfunction. Regression models assessed XQ and observer-graded xerostomia predictors. Results Statistically significant predictors of the XQ score in univariate analysis included OC, PG, and SMG mean doses, as well as baseline XQ score, time since RT, and both stimulated and unstimulated PG saliva flow rates. Similar factors were statistically significant predictors of observer-graded xerostomia. OC, PG and SMG mean doses were moderately inter-correlated (r=0.47–0.55). In multivariate analyses, after adjusting for PG and SMG doses, OC mean dose (p xerostomia. While scatter plots showed no thresholds, OC mean doses xerostomia at almost all post-therapy time points. Conclusion PG, SMG and OC mean doses were significant predictors of both patient-reported and observer-rated xerostomia after chemo-IMRT, with OC doses remaining significant after adjusting for PG and SMG doses. These results support efforts to spare all salivary glands by IMRT, beyond the PGs alone. PMID:22056067

  4. External beam radiotherapy for head and neck carcinomas with preservation of parotid function: indications, techniques and long term results

    International Nuclear Information System (INIS)

    Ding-Jen, Lee; Fairbanks, Robert; Lee, Frank C.

    1995-01-01

    Purpose/Objective: To reduce the incidence of radiotherapy induced xerostomia, we developed techniques of external beam irradiation with preservation of parotid function for patients with early to intermediate stage carcinomas of the head and neck. This analysis reports the efficacy of our methods. Materials and Methods: From 1985 to 1993, 42 patients with early to intermediate stage (T 1-3 N 0-2 M 0 ) head and neck carcinomas received a course of external beam radiotherapy. There were 13 patients with carcinoma of the oropharynx, 26 with carcinomas of the oral cavity and 3 with carcinomas of the hypopharynx (lateral wall). 7 patients received a course of definitive radiotherapy (66 to 72 Gy), while 35 patients received a course of postoperative radiotherapy (60-66 Gy). The fraction size was 2 Gy per day. In terms of treatment planning, the primary site (plus a margin) and the ipsilateral neck were covered by the irradiation volume. The ipsilateral parotid gland was within the treatment volume while the contralateral parotid gland was not. The most frequently used field arrangement was a paired wedge fields with an AP (medially just across the mid-line) and an ipsilateral posterior oblique field (usually 30 deg. off vertical axis with a spinal cord block). Multiple level of contours were taken and transmission blocks were used to improve dose homogeneity. In all patients, the ipsilateral parotid gland (and the neck) was irradiated while the contralateral parotid gland (and the neck) was not. Results: With a median follow up of 4 years (ranged from 1.5 to 9 years), only one patient developed symptomatic xerostomia. None had radiation induced dental caries. No patient developed recurrent disease in the contralateral neck. The local control rate was (38(42)) (90%) in the primary site and(41(42)) (98%) in the ipsilateral neck. Conclusion: With appropriate treatment planning, external beam irradiation with parotid function preservation can be achieved. Our results

  5. Radiation Sialadenitis Induced by High-dose Radioactive Iodine Therapy

    International Nuclear Information System (INIS)

    Jeong, Shin Young; Lee, Jaetae

    2010-01-01

    Radioactive iodine ( 131 I) is accumulated in the thyroid tissue and plays an important role in the treatment of differentiated papillary and follicular cancers after thyroidectomy. Simultaneously, 131 I is concentrated in the salivary glands and secreted into the saliva. Dose-related damage to the salivary parenchyma results from the 131 I irradiation. Salivary gland swelling and pain, usually involving the parotid, can be seen. The symptoms may develop immediately after a therapeutic dose of 131 I and/or months later and progress in intensity with time. In conjunction with the radiation sialadenitis, secondary complications reported include xerostomia, taste alterations, infection, increases in caries, facial nerve involvement, candidiasis, and neoplasia. Prevention of 131 I sialadenitis may involve the use of sialogogic agents to hasten the transit time of the radioactive iodine through the salivary glands. However, studies are not available to delineate the efficacy of this approach. Treatment of the varied complications that may develop encompass numerous approaches and include gland massage, sialogogic agents, duct probing, antibiotics, mouthwashes, good oral hygiene, and adequate hydration. Recently interventional sialoendoscopy has been introduced an effective tool for the management of patients with 131 I-induced sialadenitis that is unresponsive to medical treatment.

  6. Radiation damage in the diamond based beam condition monitors of the CMS experiment at the Large Hadron Collider (LHC) at CERN

    CERN Document Server

    Guthoff, Moritz; Dabrowski, Anne; De Boer, Wim; Stickland, David; Lange, Wolfgang; Lohmann, Wolfgang

    2013-01-01

    The Beam Condition Monitor (BCM) of the CMS detector at the LHC is a protection device similar to the LHC Beam Loss Monitor system. While the electronics used is the same, poly-crystalline Chemical Vapor Deposition (pCVD) diamonds are used instead of ionization chambers as the BCM sensor material. The main purpose of the system is the protection of the silicon Pixel and Strip tracking detectors by inducing a beam dump, if the beam losses are too high in the CMS detector. By comparing the detector current with the instantaneous luminosity, the BCM detector ef fi ciency can be monitored. The number of radiation-induced defects in the diamond, reduces the charge collection distance, and hence lowers the signal. The number of these induced defects can be simulated using the FLUKA Monte Carlo simulation. The cross-section for creating defects increases with decreasing energies of the impinging particles. This explains, why diamond sensors mounted close to heavy calorimeters experience more radiation damage, becaus...

  7. High power beam profile monitor with optical transition radiation

    International Nuclear Information System (INIS)

    Denard, J.C.; Piot, P.; Capek, K.; Feldl, E.

    1997-01-01

    A simple monitor has been built to measure the profile of the high power beam (800 kW) delivered by the CEBAF accelerator at Jefferson Lab. The monitor uses the optical part of the forward transition radiation emitted from a thin carbon foil. The small beam size to be measured, about 100 μm, is challenging not only for the power density involved but also for the resolution the instrument must achieve. An important part of the beam instrumentation community believes the radiation being emitted into a cone of characteristic angle 1/γ is originated from a region of transverse dimension roughly λγ; thus the apparent size of the source of transition radiation would become very large for highly relativistic particles. This monitor measures 100 μm beam sizes that are much smaller than the 3.2 mm λγ limit; it confirms the statement of Rule and Fiorito that optical transition radiation can be used to image small beams at high energy. The present paper describes the instrument and its performance. The authors tested the foil in, up to 180 μA of CW beam without causing noticeable beam loss, even at 800 MeV, the lowest CEBAF energy

  8. Assessment of systemic effects of ginger on salivation in patients with post-radiotherapy xerostomia

    Directory of Open Access Journals (Sweden)

    Goli Chamani

    2017-07-01

    Full Text Available BACKGROUND AND AIM: Our aim was to assess the clinical efficacy of ginger capsule (Zintoma herbal capsule in the relief of symptoms in patients with post-radiotherapy xerostomia. METHODS: This study was a randomized double-blind, parallel clinical trial of ginger usage in patients with post-radiotherapy xerostomia. Sixty-one subjects were selected from patients with xerostomia of Imam Khomeini Cancer Institute, Tehran, Iran. Subject-based dry mouth scores derived from 100 mm visual analogue scales (VAS were recorded at baseline. Patients also completed a questionnaire on the first visit regarding the symptoms of xerostomia. The patients received ginger capsule (30 persons or placebo (31 persons three times daily over a 2-weeks period. At the end of day 14, dry mouth scores derived from VAS were recorded again and patients responded to the additional variables regarding dry mouth symptoms and quality of life issues. P < 0.05 was considered significant. Data were analyzed using SPSS. RESULTS: The mean treatment effect on day 14 was 33.7 ± 20.9 mm in the ginger group and 23.6 ± 17.3 mm in the placebo group. The analysis indicated marginally significant improvement of xerostomia with ginger prescription (P = 0.057. At the end of intervention there was no significant difference between the two groups regarding improvement of quality of life or dry mouth symptoms. CONCLUSION: It seems that ginger could be helpful in the treatment of xerostomia. Since ginger is considered a safe herbal medicine with only few and insignificant adverse/side effects further studies in larger group of patients are recommended to provide the effect of ginger on different complaints of xerostomia.

  9. Proton beam characterization by proton-induced acoustic emission: simulation studies

    International Nuclear Information System (INIS)

    Jones, K C; Witztum, A; Avery, S; Sehgal, C M

    2014-01-01

    Due to their Bragg peak, proton beams are capable of delivering a targeted dose of radiation to a narrow volume, but range uncertainties currently limit their accuracy. One promising beam characterization technique, protoacoustic range verification, measures the acoustic emission generated by the proton beam. We simulated the pressure waves generated by proton radiation passing through water. We observed that the proton-induced acoustic signal consists of two peaks, labeled α and γ, with two originating sources. The α acoustic peak is generated by the pre-Bragg peak heated region whereas the source of the γ acoustic peak is the proton Bragg peak. The arrival time of the α and γ peaks at a transducer reveals the distance from the beam propagation axis and Bragg peak center, respectively. The maximum pressure is not observed directly above the Bragg peak due to interference of the acoustic signals. Range verification based on the arrival times is shown to be more effective than determining the Bragg peak position based on pressure amplitudes. The temporal width of the α and γ peaks are linearly proportional to the beam diameter and Bragg peak width, respectively. The temporal separation between compression and rarefaction peaks is proportional to the spill time width. The pressure wave expected from a spread out Bragg peak dose is characterized. The simulations also show that acoustic monitoring can verify the proton beam dose distribution and range by characterizing the Bragg peak position to within ∼1 mm. (paper)

  10. DEVELOPMENT OF SHORT UNDULATORS FOR ELECTRON-BEAM-RADIATION INTERACTION STUDIES

    Energy Technology Data Exchange (ETDEWEB)

    Piot, P. [NICADD, DeKalb; Andorf, M. B. [NICADD, DeKalb; Fagerberg, G. [Northern Illinois U.; Figora, M. [Northern Illinois U.; Sturtz, A. [Northern Illinois U.

    2016-10-19

    Interaction of an electron beam with external field or its own radiation has widespread applications ranging from coherent-radiation generation, phase space cooling or formation of temporally-structured beams. An efficient coupling mechanism between an electron beam and radiation field relies on the use of a magnetic undulator. In this contribution we detail our plans to build short (11-period) undulators with 7-cm period refurbishing parts of the aladdin U3 undulator [1]. Possible use of these undulators at available test facilities to support experiments relevant to cooling techniques and radiation sources are outlined.

  11. Radiation-induced myocardial perfusion abnormalities in breast cancer patients following external beam radiation therapy

    Directory of Open Access Journals (Sweden)

    Mohammad Eftekhari

    2015-01-01

    Full Text Available Objective(s: Radiation therapy for breast cancer can induce myocardial capillary injury and increase cardiovascular morbidity and mortality. A prospective cohort was conducted to study the prevalence of myocardial perfusion abnormalities following radiation therapy of left-sided breast cancer patients as compared to those with right–sided cancer. Methods: To minimize potential confounding factors, only those patients with low 10-year risk of coronary artery disease (based on Framingham risk scoring were included. All patients were initially treated by modified radical mastectomy and then were managed by postoperative 3D Conformal Radiation Therapy (CRT to the surgical bed with an additional 1-cm margin, delivered by 46-50 Gy (in 2 Gy daily fractions over a 5-week course. The same dose-adjusted chemotherapy regimen (including anthracyclines, cyclophosphamide and taxol was given to all patients. Six months after radiation therapy, all patients underwent cardiac SPECT for the evaluation of myocardial perfusion. Results: A total of 71 patients with a mean age of 45.3±7.2 years [35 patients with leftsided breast cancer (exposed and 36 patients with right-sided cancer (controls] were enrolled. Dose-volume histogram (DVH [showing the percentage of the heart exposed to >50% of radiation] was significantly higher in patients with left-sided breast cancer. Visual interpretation detected perfusion abnormalities in 42.9% of cases and 16.7% of controls (P=0.02, Odds ratio=1.46. In semiquantitative segmental analysis, only apical (28.6% versus 8.3%, P=0.03 and anterolateral (17.1% versus 2.8%, P=0.049 walls showed significantly reduced myocardial perfusion in the exposed group. Summed Stress Score (SSS of>3 was observed in twelve cases (34.3%, while in five of the controls (13.9%,(Odds ratio=1.3. There was no significant difference between the groups regarding left ventricular ejection fraction. Conclusion: The risk of radiation induced myocardial

  12. Nonlinear effects in the radiation force generated by amplitude-modulated focused beams

    Science.gov (United States)

    González, Nuria; Jiménez, Noé; Redondo, Javier; Roig, Bernardino; Picó, Rubén; Sánchez-Morcillo, Víctor; Konofagou, Elisa E.; Camarena, Francisco

    2012-10-01

    Harmonic Motion Imaging (HMI) uses an amplitude-modulated (AM) beam to induce an oscillatory radiation force before, during and after ablation. In this paper, the findings from a numerical analysis of the effects related with the nonlinear propagation of AM focused ultrasonic beams in water on the radiation force and the location of its maxima will be presented. The numerical modeling is performed using the KZK nonlinear parabolic equation. The radiation force is generated by a focused transducer with a gain of 18, a carrier frequency of 1 MHz and a modulation frequency of 25 kHz. The modulated excitation generates a spatially-invariant force proportional to the intensity. Regarding the nonlinear wave propagation, the force is no longer proportional to the intensity, reaching a factor of eight between the nonlinear and linear estimations. Also, a 9 mm shift in the on-axis force peak occurs when the initial pressure increased from 1 to 300 kPa. This spatial shift, due to the nonlinear effects, becomes dynamic in AM focused beams, as the different signal periods have different amplitudes. This study shows that both the value and the spatial position of the force peak are affected by the nonlinear propagation of the ultrasonic waves.

  13. Radiation processing of natural polymers using low energy electron beam

    International Nuclear Information System (INIS)

    Kume, Tamikazu

    2004-01-01

    Radiation processing is widely used in Japan and the economic scale of radiation application amounted to about 71 b$ (ratio relative to GDP: 1.7%) in total. It consisted of 60 b$ (85%) in industry, 10 b$ (14%) in medicine and 1 b$ (1%) in agriculture. Irradiation using gamma-ray from 60 Co and electron beam is commercially used for the sterilization and modification of materials. Utilization of natural polymers by radiation has been investigated for recycling the natural resources and reducing the environmental pollution. Polysaccharides such as chitosan, sodium alginate, carrageenan, cellulose, pectin were easily degraded by irradiation and induced various kinds of biological activities, i.e. anti-bacterial activity, elicitor activity, plant growth promotion, suppression of environmental stress on plants. Radiation degraded chitosan was effective to enhance the growth of plants in tissue culture. Low energy electron beam (EB) irradiation has a variety of applications and good safety. A self-shielded low energy electron accelerator system needs an initial investment much lower than a 60 Co facility. It was demonstrated that the liquid sample irradiation system using low energy EB was effective not only for the preparation of degraded polysaccharides but also for radiation vulcanization of natural rubber latex (RVNRL). Some carbohydrate derivatives, carboxymethylcellulose (CMC), carboxymethyl-starch and carboxymethyl-chitin/chitosan, can be crosslinked under certain radiation condition and produced the biodegradable hydrogel for medical and agricultural use. Treatment of soybean seeds by low energy EB enhanced the growth and the number of rhizobia on the root. (author)

  14. Prevalence and impact of xerostomia on the quality of life of people living with HIV/AIDS from Brazil.

    Science.gov (United States)

    Busato, Ivana Maria Saes; Thomaz, Mariana; Toda, Alexandre Issamu; Alanis, Danilo Gustavo Pulita; França, Beatriz Helena Sottile; de Lima, Antônio Adilson Soares; Azevedo-Alanis, Luciana Reis

    2013-01-01

    To evaluate the impact of xerostomia on the quality of life (QOL) of people living with HIV/AIDS (PLWHA) from Brazil. A cross-sectional study was performed on 195 PLWHA. Xerostomia was detected by asking a question about the sensation of having "dry mouth," and Oral Health Impact Profile 14 (OHIP-14) was used to measure the impact of xerostomia on QOL. Time of diagnosis of HIV/AIDS was assessed. A total of 78 (40.0%) subjects presented with xerostomia. Xerostomia was associated with female gender, low amount of saliva perceived (p ≤ .01), difficulty in swallowing food (p ≤ .05), and showed to have a negative impact on QOL as measured by OHIP-14 (p ≤ .01). Xerostomia was frequent and showed to have a negative impact on the QOL of PLWHA. ©2012 Special Care Dentistry Association and Wiley Periodicals, Inc.

  15. Treatment Planning Constraints to Avoid Xerostomia in Head-and-Neck Radiotherapy: An Independent Test of QUANTEC Criteria Using a Prospectively Collected Dataset

    Energy Technology Data Exchange (ETDEWEB)

    Moiseenko, Vitali, E-mail: vmoiseenko@bccancer.bc.ca [Department of Medical Physics, Vancouver Cancer Centre, British Columbia Cancer Agency, Vancouver, BC (Canada); Wu, Jonn [Department of Radiation Oncology, Vancouver Cancer Centre, British Columbia Cancer Agency, Vancouver, BC (Canada); Hovan, Allan [Department of Oral Oncology, Vancouver Cancer Centre, British Columbia Cancer Agency, Vancouver, BC (Canada); Saleh, Ziad; Apte, Aditya; Deasy, Joseph O. [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Harrow, Stephen [Department of Radiation Oncology, Vancouver Cancer Centre, British Columbia Cancer Agency, Vancouver, BC (Canada); Rabuka, Carman; Muggli, Adam [Department of Oral Oncology, Vancouver Cancer Centre, British Columbia Cancer Agency, Vancouver, BC (Canada); Thompson, Anna [Department of Radiation Oncology, Vancouver Cancer Centre, British Columbia Cancer Agency, Vancouver, BC (Canada)

    2012-03-01

    Purpose: The severe reduction of salivary function (xerostomia) is a common complication after radiation therapy for head-and-neck cancer. Consequently, guidelines to ensure adequate function based on parotid gland tolerance dose-volume parameters have been suggested by the QUANTEC group and by Ortholan et al. We perform a validation test of these guidelines against a prospectively collected dataset and compared with a previously published dataset. Methods and Materials: Whole-mouth stimulated salivary flow data from 66 head-and-neck cancer patients treated with radiotherapy at the British Columbia Cancer Agency (BCCA) were measured, and treatment planning data were abstracted. Flow measurements were collected from 50 patients at 3 months, and 60 patients at 12-month follow-up. Previously published data from a second institution, Washington University in St. Louis (WUSTL), were used for comparison. A logistic model was used to describe the incidence of Grade 4 xerostomia as a function of the mean dose of the spared parotid gland. The rate of correctly predicting the lack of xerostomia (negative predictive value [NPV]) was computed for both the QUANTEC constraints and Ortholan et al. recommendation to constrain the total volume of both glands receiving more than 40 Gy to less than 33%. Results: Both datasets showed a rate of xerostomia of less than 20% when the mean dose to the least-irradiated parotid gland is kept to less than 20 Gy. Logistic model parameters for the incidence of xerostomia at 12 months after therapy, based on the least-irradiated gland, were D{sub 50} = 32.4 Gy and and {gamma} = 0.97. NPVs for QUANTEC guideline were 94% (BCCA data), and 90% (WUSTL data). For Ortholan et al. guideline NPVs were 85% (BCCA) and 86% (WUSTL). Conclusion: These data confirm that the QUANTEC guideline effectively avoids xerostomia, and this is somewhat more effective than constraints on the volume receiving more than 40 Gy.

  16. Treatment Planning Constraints to Avoid Xerostomia in Head-and-Neck Radiotherapy: An Independent Test of QUANTEC Criteria Using a Prospectively Collected Dataset

    International Nuclear Information System (INIS)

    Moiseenko, Vitali; Wu, Jonn; Hovan, Allan; Saleh, Ziad; Apte, Aditya; Deasy, Joseph O.; Harrow, Stephen; Rabuka, Carman; Muggli, Adam; Thompson, Anna

    2012-01-01

    Purpose: The severe reduction of salivary function (xerostomia) is a common complication after radiation therapy for head-and-neck cancer. Consequently, guidelines to ensure adequate function based on parotid gland tolerance dose–volume parameters have been suggested by the QUANTEC group and by Ortholan et al. We perform a validation test of these guidelines against a prospectively collected dataset and compared with a previously published dataset. Methods and Materials: Whole-mouth stimulated salivary flow data from 66 head-and-neck cancer patients treated with radiotherapy at the British Columbia Cancer Agency (BCCA) were measured, and treatment planning data were abstracted. Flow measurements were collected from 50 patients at 3 months, and 60 patients at 12-month follow-up. Previously published data from a second institution, Washington University in St. Louis (WUSTL), were used for comparison. A logistic model was used to describe the incidence of Grade 4 xerostomia as a function of the mean dose of the spared parotid gland. The rate of correctly predicting the lack of xerostomia (negative predictive value [NPV]) was computed for both the QUANTEC constraints and Ortholan et al. recommendation to constrain the total volume of both glands receiving more than 40 Gy to less than 33%. Results: Both datasets showed a rate of xerostomia of less than 20% when the mean dose to the least-irradiated parotid gland is kept to less than 20 Gy. Logistic model parameters for the incidence of xerostomia at 12 months after therapy, based on the least-irradiated gland, were D 50 = 32.4 Gy and and γ = 0.97. NPVs for QUANTEC guideline were 94% (BCCA data), and 90% (WUSTL data). For Ortholan et al. guideline NPVs were 85% (BCCA) and 86% (WUSTL). Conclusion: These data confirm that the QUANTEC guideline effectively avoids xerostomia, and this is somewhat more effective than constraints on the volume receiving more than 40 Gy.

  17. The presence of subjective feelings of xerostomia in the institutionalized elderly

    OpenAIRE

    Petrovski, Mihajlo; Minovska, Ana; Ivanovski, Kiro

    2014-01-01

    Introduction: The presence of subjective feelings of dry mouth is the most common oral problem in the institutionalized elderly. Purpose: to assess the subjective presence of xerostomia in the institutionalized elderly. Materials and method: Seventy individuals, older than 65 years and institutionalized in a particular nursing home, were evaluated. The subjective presence of xerstomia was determined. To determine the level of expressiveness of xerostomia, a questionnaire recommended b...

  18. Observation of the undulator radiation from the positron beam

    International Nuclear Information System (INIS)

    Maezawa, Hideki.

    1986-02-01

    A spectral measurement of the 1st harmonic of the undulator radiation emitted from positron beam was made on Dec. 21, 1985 during a test operation of the Photon Factory storage ring with the 2.5 GeV positron beam which was stored up to 5.5 mA. In comparison to the same measurement performed with the electron beam, no appreciable difference in the spectral properties of the undulator radiation was found between the two cases under the condition of the low beam current of a few mA. (author)

  19. Biotechnological advances in neuro-electro-stimulation for the treatment of hyposalivation and xerostomia.

    Science.gov (United States)

    Lafaurie, Gloria; Fedele, Stefano; López, Rafael Martín-Granizo; Wolff, Andy; Strietzel, Frank; Porter, Stephen R; Konttinen, Yrjö T

    2009-02-01

    Treatment of xerostomia is a common clinical challenge in the oral medicine practice. Although some treatments have been used to improve the symptoms of xerostomia, none is completely satisfactory for the patients who suffer of this alteration. In the last years non-pharmacological treatments based on electro-stimulation for the treatment of xerostomia have been developed. This review is aimed at presenting new developments for the treatment of xerostomia, applying neuro-electro-stimulation by miniaturized intra-oral electro-stimulators. These devices increase salivary secretion and improve symptoms of oral dryness. Their effect is obtained by means of stimulation of the lingual nerve, in whose proximity the electrodes of the apparatus are placed. The objective of this mechanism is both to directly stimulate the salivary glands controlled by that nerve and to enhance the salivary reflex. Clinical studies have been carried out that have demonstrated the wetting effect of the method described in this article.

  20. [Effects on salivation, xerostomia and halitosis in elders after oral function improvement exercises].

    Science.gov (United States)

    Kim, Young Jin; Park, Kyung Min

    2012-12-01

    The purpose of this study was to investigate effects of Oral Function Improvement Exercises on salivation, xerostomia and halitosis in elderly people. The participants in the study were 48 female community-dwelling elders in D city. The Oral Function Improvement Exercises were given 3 times a week, for a total of 24 times from August to October 2011. Spitting method, Visual Analogue Scale, and halimeter (mBA-21) were used to evaluate the effects of Oral Function Improvement Exercises on salivation, xerostomia, and halitosis. The data were analyzed using χ²-test and t-test with the SPSS program. The experimental group had significantly better salivation, and less xerostomia and halitosis than the control group. The results indicate that Oral Function Improvement Exercises were effective for salivation, xerostomia and halitosis in the elders. Therefore, it was suggested that Oral Function Improvement Exercise are applicable in a community nursing intervention program to improve the quality of life for elders.

  1. Xerostomia in geriatric patients: a burgeoning global concern.

    Science.gov (United States)

    Anil, Sukumaran; Vellappally, Sajith; Hashem, Mohamed; Preethanath, Reghunathan S; Patil, Shankargouda; Samaranayake, Lakshman P

    2016-02-01

    Saliva plays a key role in maintaining oral homeostasis, function, and health. The prevalence of xerostomia and its consequences are rising due to the increasing aging population, the effects of some systemic diseases, medical management, and commonly-prescribed medications that reduce saliva production. When salivary function is diminished, patients are at a greater risk of developing caries, discomfort in wearing dentures, and opportunistic diseases, such as candidiasis. The psychosocial aspects of xerostomia can range from a mild effect on self-rated oral health to frustration, embarrassment, unhappiness, or substantial disruptions in quality of life. This article reviews the clinical features, diagnosis, and prevalence of dry mouth, as well as its treatment strategies. © 2014 Wiley Publishing Asia Pty Ltd.

  2. Development of radiation-induced mutation techniques and functional genomics studies

    International Nuclear Information System (INIS)

    Kim, Dong Sub; Kang, Si Yong; Kim, Jin Baek

    2012-01-01

    This project has been performed to develop plant genetic resources using radiation (gamma-rays, ion-beam, space environments), to conduct functional genomics studies with mutant resources, and to develop new radiation plant breeding techniques using various radiation sources during 3 years. In the first section, we developed flower genetic resources, functional crop resources, and bio-industrial plant resources. In the second section, we cloned several mutated genes and studied mechanisms of gene expression and genetic diversity of mutations induced by gamma-rays. In the third section, we developed new plant breeding techniques using gamma-phytotron, heavy ion-beam, and space environments. Based on these results, a total of 8 cultivars containing Chrysanthemum, Hibiscus, kenaf, rice, and soybean were applied for plant variety protection (PVP) and a total of 4 cultivars were registered for PVP. Also, license agreement for the dwarf type Hibiscus mutant 'Ggoma' was conducted with Supro co. and the manufacturing technology for natural antioxidant pear-grape vinegar was transferred into Enzenic co. Also, 8 gene sequences, such as F3'H and LDOX genes associated with flower color in Chrysanthemum and EPSPS gene from Korean lawn grass, were registered in the database of National Center for Biotechnology Information (NCBI). In the future study, we will develop new radiation mutation breeding techniques through the mutation spectrum induced by various radiation sources, the studies for mechanism of the cellular response to radiation, and the comparative·structural·functional genomics studies for useful traits

  3. Close association between oral Candida species and oral mucosal disorders in patients with xerostomia.

    Science.gov (United States)

    Shinozaki, S; Moriyama, M; Hayashida, J-N; Tanaka, A; Maehara, T; Ieda, S; Nakamura, S

    2012-10-01

    Heightened interest in oral health has lead to an increase in patients complaining of xerostomia, which is associated with various oral mucosal disorders. In this study, we investigated the relationship between Candida species and oral mucosal disorders in patients with xerostomia. We evaluated whole salivary flow rate and presence of oral mucosal disorders in 48 patients with xerostomia and 15 healthy controls. The number of Candida species was measured as colony-forming units after propagation on selective medium. Identification of Candida at the species level was carried out by polymerase chain reaction and restriction fragment length polymorphism analysis. We then examined the relationship between Candida species and oral mucosal symptoms. Compared with controls, patients with xerostomia exhibited significantly decreased whole salivary flow rate, increased rate of oral mucosal symptoms, and higher numbers of Candida. Salivary flow rate negatively correlated with the number Candida. Among patients with oral candidiasis, Candida albicans was isolated from the tongue mucosa and Candida glabrata was isolated from the angle of the mouth. These results suggest that particular Candida species are involved in the pathogenesis of oral mucosal disorders in patients with xerostomia. © 2012 John Wiley & Sons A/S.

  4. Role of minor salivary glands in developing patient-rated xerostomia and sticky saliva during day and night.

    Science.gov (United States)

    Beetz, Ivo; Schilstra, Cornelis; Visink, Arjan; van der Schaaf, Arjen; Bijl, Henk P; van der Laan, Bernard F A M; Steenbakkers, Roel J H M; Langendijk, Johannes A

    2013-11-01

    The purpose of this prospective study was to investigate the relationship between xerostomia during the day (XERday) and night (XERnight) and sticky saliva during the day (STICday) and night (STICnight) and dose distributions in different major and minor salivary glands among head and neck cancer (HNC) patients treated with primary radiotherapy (RT) or chemoradiation (CHRT). The study population was composed of 201 consecutive HNC patients treated with intensity modulated radiotherapy (IMRT) or 3-dimensional conformal radiotherapy (3D-CRT). All patients were included in a standard follow up programme in which acute and late side effects and quality of life (QoL) were prospectively assessed, prior to, during and after treatment. The primary endpoints were XERday, XERnight, STICday, STICnight as assessed by the Groningen Radiotherapy Induced Xerostomia questionnaire (GRIX) six months after completion of treatment. Organs at risk (OARs) potentially involved in salivary function were delineated on planning-CT, including the parotid, submandibular and sublingual glands and the minor glands in the soft palate, buccal mucosa and lips. Patients with moderate-to-severe xerostomia or moderate-to-severe sticky saliva, respectively, at baseline were excluded. In order to determine which salivary glands were most important, a multivariate logistic regression analysis with an extended bootstrapping technique was used. In total, 29% and 19% of the cases suffered from XERday and XERnight, respectively. The multivariate analysis showed that baseline xerostomia and the mean parotid gland dose were the most important predictors for XERday and XERnight. At 6months after (CH)RT, 10% and 12% of the cases reported STICday and STICnight respectively. We were not able to identify prognostic factors related to dose distributions with regard to STICday. The mean submandibular gland dose was associated with STICnight. Baseline xerostomia and sticky saliva scores on the GRIX were associated

  5. Efficacy of Traditional Chinese Medicine in Treatment and Prophylaxis of Radiation-Induced Oral Mucositis in Patients Receiving Radiotherapy: A Randomized Controlled Trial.

    Science.gov (United States)

    Wang, Cong; Wang, Peiguo; Ouyang, Huaqiang; Wang, Jing; Sun, Lining; Li, Yanwei; Liu, Dongying; Jiang, Zhansheng; Wang, Bin; Pan, Zhanyu

    2018-06-01

    To estimate the efficacy of traditional Chinese medicine (Chining decoction, CHIN) for radiation-induced oral mucositis in patients with head and neck cancer. From May 2014 to December 2015, 70 consecutive patients were randomly assigned to receive CHIN (treatment group) or recombinant human epidermal growth factor (rhEGF) spray (control group) at a 1:1 ratio. CHIN was administered to treatment group from the first day of radiotherapy until the completion of radiotherapy. Simultaneously, the rhEGF spray was administered to control group on the oral mucosa of irradiated area. The clinical benefit was determined by gradation of mucositis (Common Terminology Criteria for Adverse Events v4.0), oral pain, and xerostomia (visual analysis scale) for each week during radiotherapy. Body mass index was evaluated before and after radiotherapy. Patients in the treatment group had prominent remission of oral pain and grade of mucositis on each observing point compared with those in control group ( P .05). CHIN presented an obvious advantage in preventing radiation-induced oral mucositis compared with rhEGF spray.

  6. Relationship between xerostomia and salivary flow rates in HIV-infected individuals.

    Science.gov (United States)

    Nittayananta, Wipawee; Chanowanna, Nilnara; Pruphetkaew, Nannapat; Nauntofte, Birgitte

    2013-08-01

    The aim of the present study was to determine the relationship between self-reported xerostomia and salivary flow rates among HIV-infected individuals. A cross-sectional study was performed on 173 individuals (81 HIV-infected individuals, mean age: 32 years, and 92 non-HIV controls, mean age: 30 years). Subjective complaints of dry mouth, based on a self-report of xerostomia questions, and dry mouth, based on a visual analogue scale (VAS), were recorded along with measurements of salivary flow rate of both unstimulated and wax-stimulated whole saliva. The relationship between subjective responses to the xerostomia questions, the VAS of dry mouth, and objective measurements of salivary flow rates were analyzed. Responses to the questions--Do you carry water or a saliva substitute? and Have you had taste disturbance?--were significantly different between HIV-infected and non-HIV individuals (P flow rate. A significant correlation between the VAS of dry mouth and salivary flow rates was observed (P = 0.023). Responses to self-reported xerostomia questions reflects low unstimulated salivary flow rates. Thus, questions concerning dry mouth might be useful tools to identify HIV-infected individuals with hyposalivation, especially at a resting stage. © 2013 Wiley Publishing Asia Pty Ltd.

  7. 21 CFR 892.5710 - Radiation therapy beam-shaping block.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Radiation therapy beam-shaping block. 892.5710 Section 892.5710 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... block. (a) Identification. A radiation therapy beam-shaping block is a device made of a highly...

  8. Evaluation of Xerostomia and salivary flow rate in Hashimoto's Thyroiditis.

    Science.gov (United States)

    Agha-Hosseini, Farzaneh; Shirzad, Nooshin; Moosavi, Mahdieh-Sadat

    2016-01-01

    One of the most common causes of hypothyroidism is Hashimoto's Thyroiditis (HT). Early detection of dry mouth is critical in preserving and promoting systemic and oral health. In this study we have assessed, for the first time, salivary function and xerostomia in HT patients who have not been involved with Sjögren's syndrome. HT was diagnosed in 40 patients based on clinical findings and positive anti-thyroid peroxidase antibodies (anti-TPO). Controls, matched by sex, age and body mass index (BMI), and with no history of thyroid disease, were selected. A questionnaire was used for diagnosis of xerostomia. Saliva samples were taken between 8 a.m. and 9 a.m., and at least 2 hours after the last intake of food or drink. The flow rate was calculated in milliliters per minute. Xerostomia was significantly higher in patients with HT. Unstimulated salivary flow rate was significantly lower in the HT group. Stimulated salivary flow rate was lower in HT group, but the difference was not significant. The patients with HT experienced xerostomia, and their salivary flow rate was diminished. Spitting the saliva then assessing salivary flow rate based on milliliter per minute is non-invasive, fast, and simple for chair-side diagnosis of dry mouth. Autoimmune diseases can be accompanied by salivary gland dysfunction. This may be due to the effect of cytokines in the autoimmune process or because of thyroid hormone dysfunctions.

  9. Xerostomia Quality of Life Scale (XeQoLS) questionnaire: validation of Italian version in head and neck cancer patients.

    Science.gov (United States)

    Lastrucci, Luciana; Bertocci, Silvia; Bini, Vittorio; Borghesi, Simona; De Majo, Roberta; Rampini, Andrea; Gennari, Pietro Giovanni; Pernici, Paola

    2018-01-01

    To translate the Xerostomia Quality-of-Life Scale (XeQoLS) into Italian language (XeQoLS-IT). Xerostomia is the most relevant acute and late toxicity in patients with head and neck cancer treated with radiotherapy (RT). Patient-reported outcome (PRO) instruments are subjective report on patient perception of health status. The XeQoLS consists of 15 items and measures the impact of salivary gland dysfunction and xerostomia on the four major domains of oral health-related QoL. The XeQoLS-IT was created through a linguistic validation multi-step process: forward translation (TF), backward translation (TB) and administration of the questionnaire to 35 Italian patients with head and neck cancer. Translation was independently carried out by two radiation oncologists who were Italian native speakers. The two versions were compared and adapted to obtain a reconciled version, version 1 (V1). V1 was translated back into English by an Italian pro skilled in teaching English. After review of discrepancies and choice of the most appropriate wording for clarity and similarity to the original, version 2 (V2) was reached by consensus. To evaluate version 2, patients completed the XeQoLS-IT questionnaire and also underwent a cognitive debriefing. The questionnaire was considered simple by the patients. The clarity of the instructions and the easiness to answer questions had a mean value of 4.5 (± 0.71) on a scale from 1 to 5. A valid multi-step process led to the creation of the final version of the XeQoLS-IT, a suitable instrument for the perception of xerostomia in patients treated with RT.

  10. Quantum radiation reaction in head-on laser-electron beam interaction

    International Nuclear Information System (INIS)

    Vranic, Marija; Grismayer, Thomas; Fonseca, Ricardo A; Silva, Luis O

    2016-01-01

    In this paper, we investigate the evolution of the energy spread and the divergence of electron beams while they interact with different laser pulses at intensities where quantum effects and radiation reaction are of relevance. The interaction is modelled with a quantum electrodynamic (QED)-PIC code and the results are compared with those obtained using a standard PIC code with a classical radiation reaction module. In addition, an analytical model is presented that estimates the value of the final electron energy spread after the interaction with the laser has finished. While classical radiation reaction is a continuous process, in QED, radiation emission is stochastic. The two pictures reconcile in the limit when the emitted photons energy is small compared to the energy of the emitting electrons. The energy spread of the electron distribution function always tends to decrease with classical radiation reaction, whereas the stochastic QED emission can also enlarge it. These two tendencies compete in the QED-dominated regime. Our analysis, supported by the QED module, reveals an upper limit to the maximal attainable energy spread due to stochasticity that depends on laser intensity and the electron beam average energy. Beyond this limit, the energy spread decreases. These findings are verified for different laser pulse lengths ranging from short ∼30 fs pulses presently available to the long ∼150 fs pulses expected in the near-future laser facilities, and compared with a theoretical model. Our results also show that near future experiments will be able to probe this transition and to demonstrate the competition between enhanced QED induced energy spread and energy spectrum narrowing from classical radiation reaction. (paper)

  11. Characterization of radiation damage induced by swift heavy ions in graphite

    Energy Technology Data Exchange (ETDEWEB)

    Hubert, Christian

    2016-05-15

    Graphite is a classical material in neutron radiation environments, being widely used in nuclear reactors and power plants as a moderator. For high energy particle accelerators, graphite provides ideal material properties because of the low Z of carbon and its corresponding low stopping power, thus when ion projectiles interact with graphite is the energy deposition rather low. This work aims to improve the understanding of how the irradiation with swift heavy ions (SHI) of kinetic energies in the range of MeV to GeV affects the structure of graphite and other carbon-based materials. Special focus of this project is given to beam induced changes of thermo-mechanical properties. For this purpose the Highly oriented pyrolytic graphite (HOPG) and glassy carbon (GC) (both serving as model materials), isotropic high density polycrystalline graphite (PG) and other carbon based materials like carbon fiber carbon composites (CFC), chemically expanded graphite (FG) and molybdenum carbide enhanced graphite composites (MoC) were exposed to different ions ranging from {sup 131}Xe to {sup 238}U provided by the UNILAC accelerator at GSI in Darmstadt, Germany. To investigate structural changes, various in-situ and off-line measurements were performed including Raman spectroscopy, x-ray diffraction and x-ray photo-electron spectroscopy. Thermo-mechanical properties were investigated using the laser-flash-analysis method, differential scanning calorimetry, micro/nano-indentation and 4-point electrical resistivity measurements. Beam induced stresses were investigated using profilometry. Obtained results provided clear evidence that ion beam-induced radiation damage leads to structural changes and degradation of thermal, mechanical and electrical properties of graphite. PG transforms towards a disordered sp2 structure, comparable to GC at high fluences. Irradiation-induced embrittlement is strongly reducing the lifetime of most high-dose exposed accelerator components. For

  12. Electrical nerve stimulation for xerostomia: A meta-analysis of randomised controlled trials

    Directory of Open Access Journals (Sweden)

    Gowri Sivaramakrishnan

    2017-10-01

    Conclusion: To conclude, the current evidence does not support the use of TENS in patients with xerostomia and may be considered as a salivary substitute for symptomatic improvement. However the type, frequency and amplitude of current used needs to be studied in detail. High quality randomized controlled trials with adequate power are required, either to support or refute the use of TENS in xerostomia.

  13. Electron beam induced modification of grafted polyamides

    International Nuclear Information System (INIS)

    Timus, D.M.; Brasoveanu, M.M.; Bradley, D.A.; Popov, A.M.

    1998-01-01

    It is well known that irradiation, when applied on its own or in combination with other physical and chemical treatments, can manifest in radiation damage to materials. Radiation processing technology focuses upon producing favourable modification of materials through use of relatively high dose and dose rates. Current interest is in modifying the thermal and electrical properties of textured polymers in an effort to improve safety and wear comfort of clothing. No less important is the production of textiles which are safe to use, both in homes and offices. Present investigations provide additional data in support of findings which show that polyamides, a particular class of textured polymer, are amenable to radiation processing. Accelerated electron beam irradiation of sheets of polyamide fibre results in induced grafting of acrylic and methacrylic acids. The degree of grafting is critically dependent upon irradiation dose and the extent of monomers dilution. Of particular importance is the high correlation which is found between degree of grafting and a decrease in the softening rate of the modified polyamide. A systematic modification of electrical conductivity is also observed. (author)

  14. Application of controlled radiation-induced degradation in polymers: less exploited aspect of radiation processing of polymers

    International Nuclear Information System (INIS)

    Haji Saeid, M.; Guven, O.

    2007-01-01

    Industrial use of ionizing radiation treatment has been most successful in applications related to polymeric materials. The polymer, plastics and rubber industries have benefited from the unique advantages of ionizing radiation since its inception as an industrial tool to modify their properties and manufacture novel materials with value addition to the end product. The established and emerging applications of electron beam processing of polymers are based on the well known ultimate effects of ionizing radiation on polymers namely, crosslinking, curing, grafting and chain scissioning. Radiation-induced crosslinking dominates most applications, whereas the chain scissioning effect is much less explored and currently limited to radiation-induced degradation of Teflon, cellulose and polypropylene. The controlling of radiation-induced degradation for achieving a target average molecular weight or distribution has been evaluated for some polysaccharides, biopolymers and waste inner tubes whereas mitigation of the degradative effects of radiation has been analyzed from the point of view of using certain stabilizers, copolymers and annealing at an appropriate temperature. Several new or highly specialized techniques such as positron annihilation lifetime spectroscopy. Rutherford backscattering, elastic recoil detection analysis and solid waste NMR spectroscopy and gas chromatography-mass spectroscopy have been applied to the study or radiation-induced degradation. New information has been collected on the morphological changes associated with radiation-induced degradation processes, including chain scission, oxidation and free volume alteration. The IAEA coordinated research project (CRP) on Controlling of Degradation Effects in Radiation Processing of Polymers dealt with the role and importance of using ionizing radiation in controlling properties of natural and synthetic polymers through its degradative effect. This paper provides a summary of most important results

  15. Prior image constrained scatter correction in cone-beam computed tomography image-guided radiation therapy.

    Science.gov (United States)

    Brunner, Stephen; Nett, Brian E; Tolakanahalli, Ranjini; Chen, Guang-Hong

    2011-02-21

    X-ray scatter is a significant problem in cone-beam computed tomography when thicker objects and larger cone angles are used, as scattered radiation can lead to reduced contrast and CT number inaccuracy. Advances have been made in x-ray computed tomography (CT) by incorporating a high quality prior image into the image reconstruction process. In this paper, we extend this idea to correct scatter-induced shading artifacts in cone-beam CT image-guided radiation therapy. Specifically, this paper presents a new scatter correction algorithm which uses a prior image with low scatter artifacts to reduce shading artifacts in cone-beam CT images acquired under conditions of high scatter. The proposed correction algorithm begins with an empirical hypothesis that the target image can be written as a weighted summation of a series of basis images that are generated by raising the raw cone-beam projection data to different powers, and then, reconstructing using the standard filtered backprojection algorithm. The weight for each basis image is calculated by minimizing the difference between the target image and the prior image. The performance of the scatter correction algorithm is qualitatively and quantitatively evaluated through phantom studies using a Varian 2100 EX System with an on-board imager. Results show that the proposed scatter correction algorithm using a prior image with low scatter artifacts can substantially mitigate scatter-induced shading artifacts in both full-fan and half-fan modes.

  16. Electron beam instrumentation techniques using coherent radiation

    International Nuclear Information System (INIS)

    Wang, D.X.

    1997-01-01

    Much progress has been made on coherent radiation research since coherent synchrotron radiation was first observed in 1989. The use of coherent radiation as a bunch length diagnostic tool has been studied by several groups. In this paper, brief introductions to coherent radiation and far-infrared measurement are given, the progress and status of their beam diagnostic application are reviewed, different techniques are described, and their advantages and limitations are discussed

  17. Development of radiation-induced mutation techniques and functional genomics studies

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dong Sub; Kang, Si Yong; Kim, Jin Baek [KAERI, Daejeon (Korea, Republic of); and others

    2012-01-15

    This project has been performed to develop plant genetic resources using radiation (gamma-rays, ion-beam, space environments), to conduct functional genomics studies with mutant resources, and to develop new radiation plant breeding techniques using various radiation sources during 3 years. In the first section, we developed flower genetic resources, functional crop resources, and bio-industrial plant resources. In the second section, we cloned several mutated genes and studied mechanisms of gene expression and genetic diversity of mutations induced by gamma-rays. In the third section, we developed new plant breeding techniques using gamma-phytotron, heavy ion-beam, and space environments. Based on these results, a total of 8 cultivars containing Chrysanthemum, Hibiscus, kenaf, rice, and soybean were applied for plant variety protection (PVP) and a total of 4 cultivars were registered for PVP. Also, license agreement for the dwarf type Hibiscus mutant 'Ggoma' was conducted with Supro co. and the manufacturing technology for natural antioxidant pear-grape vinegar was transferred into Enzenic co. Also, 8 gene sequences, such as F3'H and LDOX genes associated with flower color in Chrysanthemum and EPSPS gene from Korean lawn grass, were registered in the database of National Center for Biotechnology Information (NCBI). In the future study, we will develop new radiation mutation breeding techniques through the mutation spectrum induced by various radiation sources, the studies for mechanism of the cellular response to radiation, and the comparative{center_dot}structural{center_dot}functional genomics studies for useful traits.

  18. High prevalence of thyroid disease and role of salivary gland scintigraphy in patients with xerostomia

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Ji Hoon; Lee, Chang Hee; Son, Seung Hyun; Jeong, Ju Hye; Jeong, Shin Young; Lee, Sang Woo; Lee, Jae Tae; Ahn, Byeong Cheol [Dept. of Nuclear Medicine, Kyungpook National University School of Medicine/Hospital, Daegu (Korea, Republic of)

    2017-06-15

    Although Sjös syndrome (SS) is the most common disease causing xerostomia, autoimmune thyroid diseases can also affect the salivary glands. The aim of our study was to estimate the prevalence of thyroid diseases (TD) in subjects with symptoms of xerostomia and evaluate the efficacy of salivary gland scintigraphy (SGS) in the detection of TD in patients with SS and without SS. We retrospectively reviewed the SGS findings of 173 subjects (men:women, 29:144) with symptoms of xerostomia. Ejection fractions (EF) in the parotid and submandibular glands were calculated. Thyroid disease was diagnosed on the basis of the results of the visual assessment of tracer uptake in the thyroid gland on SGS images as well as serological thyroid function tests. Based on the American-European Criteria, 94 patients were diagnosed with SS. Hashimoto's thyroiditis was diagnosed in 63 patients, subacute thyroiditis in 23, subclinical hypothyroidism in five, and Graves' disease in one. There were significant differences in the EF values of the parotid and submandibular glands between patients with TD and those with undetermined diagnoses. More than half of patients with xerostomia exhibited TD. Thyroid assessment by SGS is feasible, and SGS appears to be useful for the patients with xerostomia caused by TD. SGS may be the first imaging modality capable of evaluating both salivary gland function and thyroid gland status in patients with xerostomia. This strategy would make the requirement for additional workup for thyroid disease.

  19. High prevalence of thyroid disease and role of salivary gland scintigraphy in patients with xerostomia

    International Nuclear Information System (INIS)

    Jung, Ji Hoon; Lee, Chang Hee; Son, Seung Hyun; Jeong, Ju Hye; Jeong, Shin Young; Lee, Sang Woo; Lee, Jae Tae; Ahn, Byeong Cheol

    2017-01-01

    Although Sjös syndrome (SS) is the most common disease causing xerostomia, autoimmune thyroid diseases can also affect the salivary glands. The aim of our study was to estimate the prevalence of thyroid diseases (TD) in subjects with symptoms of xerostomia and evaluate the efficacy of salivary gland scintigraphy (SGS) in the detection of TD in patients with SS and without SS. We retrospectively reviewed the SGS findings of 173 subjects (men:women, 29:144) with symptoms of xerostomia. Ejection fractions (EF) in the parotid and submandibular glands were calculated. Thyroid disease was diagnosed on the basis of the results of the visual assessment of tracer uptake in the thyroid gland on SGS images as well as serological thyroid function tests. Based on the American-European Criteria, 94 patients were diagnosed with SS. Hashimoto's thyroiditis was diagnosed in 63 patients, subacute thyroiditis in 23, subclinical hypothyroidism in five, and Graves' disease in one. There were significant differences in the EF values of the parotid and submandibular glands between patients with TD and those with undetermined diagnoses. More than half of patients with xerostomia exhibited TD. Thyroid assessment by SGS is feasible, and SGS appears to be useful for the patients with xerostomia caused by TD. SGS may be the first imaging modality capable of evaluating both salivary gland function and thyroid gland status in patients with xerostomia. This strategy would make the requirement for additional workup for thyroid disease

  20. Polymers under ionizing radiation: the study of energy transfers to radiation induced defects

    International Nuclear Information System (INIS)

    Ventura, A.

    2013-01-01

    Radiation-induced defects created in polymers submitted to ionizing radiations, under inert atmosphere, present the same trend as a function of the dose. When the absorbed dose increases, their concentrations increase then level off. This behavior can be assigned to energy transfers from the polymer to the previously created macromolecular defects; the latter acting as energy sinks. During this thesis, we aimed to specify the influence of a given defect, namely the trans-vinylene, in the behavior of polyethylene under ionizing radiations. For this purpose, we proposed a new methodology based on the specific insertion, at various concentrations, of trans-vinylene groups in the polyethylene backbone through chemical synthesis. This enables to get rid of the variety of created defects on one hand and on the simultaneity of their creation on the other hand. Modified polyethylenes, containing solely trans-vinylene as odd groups, were irradiated under inert atmosphere, using either low LET beams (gamma, beta) or high LET beams (swift heavy ions). During irradiations, both macromolecular defects and H 2 emission were quantified. According to experimental results, among all defects, the influence of the trans-vinylene on the behavior of polyethylene is predominant. (author) [fr

  1. Ion-beam induced structure modifications in amorphous germanium

    International Nuclear Information System (INIS)

    Steinbach, Tobias

    2012-01-01

    Object of the present thesis was the systematic study of ion-beam induced structure modifications in amorphous germanium (a-Ge) layers due to low- (LEI) and high-energetic (SHI) ion irradiation. The LEI irradiation of crystalline Ge (c-Ge) effects because the dominating nuclear scattering of the ions on the solid-state atoms the formation of a homogeneous a-Ge Layer. Directly on the surface for fluences of two orders of magnitude above the amorphization fluence the formation of stable cavities independently on the irradiation conditions was observed. For the first time for the ion-beam induced cavity formation respectively for the steady expansion of the porous layer forming with growing fluence a linear dependence on the energy ε n deposed in nuclear processes was detected. Furthermore the formation of buried cavities was observed, which shows a dependence on the type of ions. While in the c-Ge samples in the range of the high electronic energy deposition no radiation defects, cavities, or plastic deformations were observed, the high electronic energy transfer in the 3.1 μm thick pre-amorphized a-Ge surface layers leads to the formation of randomly distributed cavities. Basing on the linear connection between cavity-induced vertical volume expansion and the fluence determined for different energy transfers for the first time a material-specific threshold value of ε e HRF =(10.5±1.0) kev nm -1 was determined, above which the ion-beam induced cavity formation in a-Ge sets on. The anisotropic plastic deformation of th a-Ge layer superposed at inclined SHI irradiation on the cavity formation was very well described by an equation derived from the viscoelastic Maxwell model, but modified under regardment of the experimental results. The positive deformation yields determined thereby exhibit above a threshold value for the ion-beam induced plastic deformation ε e S a =(12±2) keV nm -1 for the first time extracted for a Ge the characteristic linear behaviour of the

  2. Self-reported prevalence and severity of xerostomia and its related conditions in individuals attending hospital for general health examinations.

    Science.gov (United States)

    Lee, E; Lee, Y-H; Kim, W; Kho, H-S

    2014-04-01

    The aim of this study was to investigate the prevalence, severity, and relationships between xerostomia and its related symptoms in individuals who attended hospital for general health examinations. Participants included 883 men and 618 women aged between 30 and 60 years. History of symptoms during the previous 6 months, current symptoms, and severity of current symptoms were evaluated using a questionnaire that included questions about xerostomia, burning mouth, taste disturbance, and oral malodor. The prevalence of xerostomia and its related symptoms was 60.2%; the prevalence of oral malodor was 52.3%, xerostomia 33.0%, burning mouth 13.6%, and taste disturbance 12.5%. Men in their 30s and women in their 60s showed significantly higher prevalence and greater severity of xerostomia, burning mouth, and taste disturbance compared with their counterparts. The prevalence of xerostomia, burning mouth, and taste disturbance, and the severity of xerostomia increased significantly with age in women. The prevalence and severity of these four symptoms were significantly related and the association was the highest between burning mouth and taste disturbance. In conclusion, xerostomia and its related symptoms were highly prevalent at all ages. The prevalence and severity of these symptoms were closely related. Copyright © 2013 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  3. Radiation Sialadenitis Induced by High-dose Radioactive Iodine Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Shin Young; Lee, Jaetae [Kyungpook National University Hospital, Daegu (Korea, Republic of)

    2010-06-15

    Radioactive iodine ({sup 131}I) is accumulated in the thyroid tissue and plays an important role in the treatment of differentiated papillary and follicular cancers after thyroidectomy. Simultaneously, {sup 131}I is concentrated in the salivary glands and secreted into the saliva. Dose-related damage to the salivary parenchyma results from the {sup 131}I irradiation. Salivary gland swelling and pain, usually involving the parotid, can be seen. The symptoms may develop immediately after a therapeutic dose of {sup 131}I and/or months later and progress in intensity with time. In conjunction with the radiation sialadenitis, secondary complications reported include xerostomia, taste alterations, infection, increases in caries, facial nerve involvement, candidiasis, and neoplasia. Prevention of {sup 131}I sialadenitis may involve the use of sialogogic agents to hasten the transit time of the radioactive iodine through the salivary glands. However, studies are not available to delineate the efficacy of this approach. Treatment of the varied complications that may develop encompass numerous approaches and include gland massage, sialogogic agents, duct probing, antibiotics, mouthwashes, good oral hygiene, and adequate hydration. Recently interventional sialoendoscopy has been introduced an effective tool for the management of patients with {sup 131}I-induced sialadenitis that is unresponsive to medical treatment.

  4. A relationship between salivary flow rates and Candida counts in patients with xerostomia.

    Science.gov (United States)

    Nadig, Suchetha Devendrappa; Ashwathappa, Deepak Timmasandra; Manjunath, Muniraju; Krishna, Sowmya; Annaji, Araleri Gopalkrishna; Shivaprakash, Praveen Kunigal

    2017-01-01

    Most of the adult population is colonized by Candida in their oral cavity. The process of colonization depends on several factors, including the interaction between Candida and salivary proteins. Therefore, salivary gland hypofunction may alter the oral microbiota and increase the risk for opportunistic infections, such as candidiasis. Hence, it is necessary to evaluate the relationship between salivary flow rates (SFRs) and Candida colony counts in the saliva of patients with xerostomia. This study aims to determine and evaluate the relationship between SFRs and Candida colony forming units (CFUs) in patients with xerostomia. This study was a descriptive study. The study participants were taken from the patients attending outpatient department in a private dental college. Fifty patients, who reported xerostomia in a questionnaire of the symptoms of xerostomia, were selected. Chewing stimulated whole saliva samples were collected from them and their SFRs were assessed. Saliva samples were inoculated in the Sabouraud dextrose agar culture media for 24-48 h, and Candida CFUs were counted. Chi-squared test was used to analyze the data. There was a significant inverse relationship between salivary flow and candida CFUs count when patients with high colony counts were analyzed (cutoff point of 400 or greater CFU/mL). Females had less SFR than males. Most of the patients who had hyposalivation were taking medication for the underlying systemic diseases. Candida albicans was the most frequent species. There was a significantly negative correlation between SFRs and Candida CFUs in the patients with xerostomia.

  5. Salivary flow and xerostomia in older patients with type 2 diabetes mellitus.

    Science.gov (United States)

    Lima, Danilo Lopes Ferreira; Carneiro, Sandro Dias Rocha Mendes; Barbosa, Fladia Taciana de Sousa; Saintrain, Maria Vieira de Lima; Moizan, Jean André Hervé; Doucet, Jean

    2017-01-01

    To assess salivary flow in older patients with type 2 diabetes mellitus (DM2) and its association with xerostomia. Cross-sectional clinical study conducted with older patients diagnosed with type 2 diabetes for at least one year receiving treatment at the Integrated Center for Diabetes and Hypertension of Ceará (CIHD) in the city of Fortaleza, Ceará, Northeastern Brazil. Oral clinical examination was carried out to assess the decayed, missing and filled teeth index (DMFT). Perception of the presence of xerostomia/dry mouth was assessed using the Visual Analogue Scale. Stimulated salivary flow was measured and samples were obtained using an extra-soft silicone device. 120 older patients with diabetes (60 insulin-dependent and 60 non-insulin-dependent) aged 65-91 years, with a mean age of 72.26 ± 6.53 years, were assessed. Of these, 111 (92.5%) presented a decrease in salivary flow while 59 (49.2%) reported moderate to severe xerostomia/dry mouth. The DMFT Index presented a mean of 27.53 ± 4.86 teeth. Reduced salivary flow was found in the group assessed in the present research; however, this finding is not in accordance with the perception of xerostomia/dry mouth reported by the patients.

  6. Salivary flow and xerostomia in older patients with type 2 diabetes mellitus.

    Directory of Open Access Journals (Sweden)

    Danilo Lopes Ferreira Lima

    Full Text Available To assess salivary flow in older patients with type 2 diabetes mellitus (DM2 and its association with xerostomia.Cross-sectional clinical study conducted with older patients diagnosed with type 2 diabetes for at least one year receiving treatment at the Integrated Center for Diabetes and Hypertension of Ceará (CIHD in the city of Fortaleza, Ceará, Northeastern Brazil. Oral clinical examination was carried out to assess the decayed, missing and filled teeth index (DMFT. Perception of the presence of xerostomia/dry mouth was assessed using the Visual Analogue Scale. Stimulated salivary flow was measured and samples were obtained using an extra-soft silicone device.120 older patients with diabetes (60 insulin-dependent and 60 non-insulin-dependent aged 65-91 years, with a mean age of 72.26 ± 6.53 years, were assessed. Of these, 111 (92.5% presented a decrease in salivary flow while 59 (49.2% reported moderate to severe xerostomia/dry mouth. The DMFT Index presented a mean of 27.53 ± 4.86 teeth.Reduced salivary flow was found in the group assessed in the present research; however, this finding is not in accordance with the perception of xerostomia/dry mouth reported by the patients.

  7. Reducing Xerostomia After Chemo-IMRT for Head-and-Neck Cancer: Beyond Sparing the Parotid Glands

    Energy Technology Data Exchange (ETDEWEB)

    Little, Michael [Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States); Schipper, Matthew [Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States); Cancer Center Biostatistics Core, University of Michigan, Ann Arbor, MI (United States); Feng, Felix Y.; Vineberg, Karen [Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States); Cornwall, Craig; Murdoch-Kinch, Carol-Anne [Hospital Dentistry, University of Michigan, Ann Arbor, MI (United States); Eisbruch, Avraham, E-mail: eisbruch@umich.edu [Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States)

    2012-07-01

    Purpose: To assess whether, in addition to sparing the parotid glands (PGs), xerostomia after chemotherapy plus intensity-modulated radiotherapy (chemo-IMRT) for head-and-neck cancer is affected by reducing the dose to the other salivary glands. Patients and Methods: In a prospective study, 78 patients with Stage III-IV oropharynx/nasopharynx cancer underwent chemo-IMRT, with the aim of sparing the parts of the bilateral PGs, oral cavity (OC) containing the minor salivary glands, and contralateral submandibular gland (SMG) outside the target (when contralateral level I was not a target). Before therapy and periodically for 24 months, validated patient-reported xerostomia questionnaire (XQ) scores and observer-graded xerostomia scores were recorded. Also, the stimulated and unstimulated saliva was measured selectively from each of the PGs and SMGs. The mean OC doses served as surrogates of minor salivary gland dysfunction. Regression models assessed the XQ and observer-graded xerostomia predictors. Results: Statistically significant predictors of the XQ score on univariate analysis included the OC, PG, and SMG mean doses and the baseline XQ score, time since RT, and both stimulated and unstimulated PG saliva flow rates. Similar factors were statistically significant predictors of observer-graded xerostomia. The OC, PG, and SMG mean doses were moderately intercorrelated (r = 0.47-0.55). On multivariate analyses, after adjusting for the PG and SMG doses, the OC mean dose (p < .0001), interval from RT (p < .0001), and stimulated PG saliva (p < .0025) were significant predictors of the XQ scores and the OC mean dose and time for observer-graded xerostomia. Although scatter plots showed no thresholds, an OC mean dose of <40 Gy and contralateral SMG mean dose of <50 Gy were each associated with low patient-reported and observer-rated xerostomia at almost all post-therapy points. Conclusion: The PG, SMG, and OC mean doses were significant predictors of both patient

  8. Reducing Xerostomia After Chemo-IMRT for Head-and-Neck Cancer: Beyond Sparing the Parotid Glands

    International Nuclear Information System (INIS)

    Little, Michael; Schipper, Matthew; Feng, Felix Y.; Vineberg, Karen; Cornwall, Craig; Murdoch-Kinch, Carol-Anne; Eisbruch, Avraham

    2012-01-01

    Purpose: To assess whether, in addition to sparing the parotid glands (PGs), xerostomia after chemotherapy plus intensity-modulated radiotherapy (chemo-IMRT) for head-and-neck cancer is affected by reducing the dose to the other salivary glands. Patients and Methods: In a prospective study, 78 patients with Stage III-IV oropharynx/nasopharynx cancer underwent chemo-IMRT, with the aim of sparing the parts of the bilateral PGs, oral cavity (OC) containing the minor salivary glands, and contralateral submandibular gland (SMG) outside the target (when contralateral level I was not a target). Before therapy and periodically for 24 months, validated patient-reported xerostomia questionnaire (XQ) scores and observer-graded xerostomia scores were recorded. Also, the stimulated and unstimulated saliva was measured selectively from each of the PGs and SMGs. The mean OC doses served as surrogates of minor salivary gland dysfunction. Regression models assessed the XQ and observer-graded xerostomia predictors. Results: Statistically significant predictors of the XQ score on univariate analysis included the OC, PG, and SMG mean doses and the baseline XQ score, time since RT, and both stimulated and unstimulated PG saliva flow rates. Similar factors were statistically significant predictors of observer-graded xerostomia. The OC, PG, and SMG mean doses were moderately intercorrelated (r = 0.47–0.55). On multivariate analyses, after adjusting for the PG and SMG doses, the OC mean dose (p < .0001), interval from RT (p < .0001), and stimulated PG saliva (p < .0025) were significant predictors of the XQ scores and the OC mean dose and time for observer-graded xerostomia. Although scatter plots showed no thresholds, an OC mean dose of <40 Gy and contralateral SMG mean dose of <50 Gy were each associated with low patient-reported and observer-rated xerostomia at almost all post-therapy points. Conclusion: The PG, SMG, and OC mean doses were significant predictors of both patient

  9. Dosimetry of beams for negative pi-meson radiation therapy

    International Nuclear Information System (INIS)

    Dicello, J.F.

    1976-01-01

    Several new facilities have been built in the last few years which can produce high intensity beams of pions. As a result, a significant amount of new data related to pion dosimetry is available. Results of beam composition, beam shaping, and collimation are given along with depth dose curves and isodose contours. Experimental data which describe the radiation quality of pion beams and the change in radiation quality with position are presented. Experimental data determining the fraction of the dose resulting from neutrons are discussed. The present techniques used in pion dosimetry are summarized, and those areas of pion dosimetry which require additional effort in order to achieve routine treatment planning for patients are reviewed

  10. PEP radiation shielding tests in SLAC A Beam

    International Nuclear Information System (INIS)

    Ash, W.; DeStaebler, H.; Harris, J.; Jenkins, T.; Murray, J.

    1977-09-01

    Radiation shielding tests designed to simulate possible conditions in and around the PEP experimental halls were conducted. The SLAC A Beam was targeted in the block tunnel at a point about midway between End Station A and Beam Dump East. At that site it was relatively easy to rearrange the concrete block structure to simulate the various shielding configurations under consideration for PEP. Extensive surveys of neutron and ionizing radiation were made. Complete results of the shielding tests are given

  11. Association of Xerostomia and Ultrasonographic Features of the Major Salivary Glands After Radioactive Iodine Ablation for Papillary Thyroid Carcinoma.

    Science.gov (United States)

    Soo Roh, Sang; Wook Kim, Dong; Jin Baek, Hye

    2016-11-01

    The objective of this study is to evaluate the association between xerostomia and sonographic features of the major salivary glands after patients undergo radioactive iodine ablation (RIA) for papillary thyroid carcinoma (PTC). The study included 256 consecutive patients who underwent total thyroidectomy, RIA, and neck ultrasound examinations. Changes in the ultrasound features of the parotid and submandibular glands after RIA were evaluated retrospectively by a single radiologist, on the basis of direct comparison of sonograms obtained before and after RIA. Clinical data, including the presence of xerostomia, were investigated retrospectively by the same radiologist via a review of the electronic medical records. For 111 of the 256 patients (43.4%), ultrasound examination revealed changes in the major salivary glands after RIA. The presence of xerostomia was undetermined in 85 of the 256 patients. Among the remaining 171 patients, the frequency of xerostomia was 36.8% (63/171). When patients with xerostomia were compared with those without xerostomia, no statistically significant differences in patient sex and age, the dose of RIA received, or the number of RIA sessions were noted (p > 0.05). Considering the changes in the ultrasound features of the major salivary glands after RIA, no statistically significant association was found between xerostomia and the number of involved major salivary glands or the presence of an involved submandibular gland (p > 0.05). In this study, ultrasound was unhelpful for evaluating xerostomia after RIA in patients with PTC.

  12. Cherenkov Radiation from a Pseudospark-sourced Electron Beam

    International Nuclear Information System (INIS)

    Phelps, A.D.R.; Yin, H.; Cross, A.W.; He, W.; Ronald, K.

    2003-01-01

    Electron beam generation from a multi-gap pseudospark discharge was investigated. A pseudospark-sourced electron beam has two phases, an initial hollow cathode phase (HCP) beam followed by a conductive phase (CP) beam. The beam brightness was measured by a field-free collimator to be 109 and 1011 Am-2rad-2 for the hollow cathode phase (HCP) beam and the conductive phase (CP) beam respectively. The initial HCP beam from an eight-gap pseudospark discharge was applied in a Cherenkov interaction between the electron beam and the TM01 mode of a 60-cm long alumina-lined waveguide. It was found experimentally that significant microwave radiation was generated only when the dielectric was present in the interaction space. If there was no dielectric in the cylindrical waveguide, then a very small background microwave output was detected even when the guide B-field was absent. This demonstrated, in conjunction with the observation that the microwave output signal was independent of the guide magnetic field over the range 0.13 to 0.26 T, that the radiation from the experiment was due to the Cherenkov interaction mechanism. In addition, two components of the microwave pulse were observed corresponding to the two energy components of the electron beam during the pseudospark discharge breakdown. These results demonstrated that the microwave radiation was generated by Cherenkov amplification of the broadband emission from the pseudospark discharge itself. A background signal level of around 100 W was measured in the frequency range 20 - 50 GHz with a percentage of (2.7 ± 0.6)% in the frequency range 25.5 - 28.6 GHz, when the dielectric lining was removed from the maser. The frequency of the microwave output after the Cherenkov maser interaction was measured to be mainly around 25.5 GHz and the dominating mode was identified as being TM01. The duration of the microwave pulse was approximately 80 ns, with a peak power of around 2 ± 0.2 kW. The gain of this amplifier was measured

  13. Influence of intravenous amifostine on xerostomia, tumor control, and survival after radiotherapy for head-and- neck cancer: 2-year follow-up of a prospective, randomized, phase III trial

    International Nuclear Information System (INIS)

    Wasserman, Todd H.; Brizel, David M.; Henke, Michael; Monnier, Alain; Eschwege, Francois; Sauer, Rolf; Strnad, Vratislav

    2005-01-01

    Purpose: To evaluate chronic xerostomia and tumor control 18 and 24 months after initial treatment with amifostine in a randomized controlled trial of patients with head-and-neck cancer; at 12 months after radiotherapy (RT), amifostine had been shown to reduce xerostomia without changing tumor control. Methods and Materials: Adults with head-and-neck cancer who underwent once-daily RT for 5-7 weeks (total dose, 50-70 Gy) received either open-label amifostine (200 mg/m 2 i.v.) 15-30 min before each fraction of radiation (n = 150) or RT alone (control; n = 153). Results: Amifostine administration was associated with a reduced incidence of Grade ≥2 xerostomia over 2 years of follow-up (p = 0.002), an increase in the proportion of patients with meaningful (>0.1 g) unstimulated saliva production at 24 months (p = 0.011), and reduced mouth dryness scores on a patient benefit questionnaire at 24 months (p < 0.001). Locoregional control rate, progression-free survival, and overall survival were not significantly different between the amifostine group and the control group. Conclusions: Amifostine administration during head-and-neck RT reduces the severity and duration of xerostomia 2 years after treatment and does not seem to compromise locoregional control rates, progression-free survival, or overall survival

  14. Role of minor salivary glands in developing patient-rated xerostomia and sticky saliva during day and night

    International Nuclear Information System (INIS)

    Beetz, Ivo; Schilstra, Cornelis; Visink, Arjan; Schaaf, Arjen van der; Bijl, Henk P.; Laan, Bernard F.A.M. van der; Steenbakkers, Roel J.H.M.; Langendijk, Johannes A.

    2013-01-01

    Purpose: The purpose of this prospective study was to investigate the relationship between xerostomia during the day (XER day ) and night (XER night ) and sticky saliva during the day (STIC day ) and night (STIC night ) and dose distributions in different major and minor salivary glands among head and neck cancer (HNC) patients treated with primary radiotherapy (RT) or chemoradiation (CHRT). Methods and materials: The study population was composed of 201 consecutive HNC patients treated with intensity modulated radiotherapy (IMRT) or 3-dimensional conformal radiotherapy (3D-CRT). All patients were included in a standard follow up programme in which acute and late side effects and quality of life (QoL) were prospectively assessed, prior to, during and after treatment. The primary endpoints were XER day , XER night , STIC day , STIC night as assessed by the Groningen Radiotherapy Induced Xerostomia questionnaire (GRIX) six months after completion of treatment. Organs at risk (OARs) potentially involved in salivary function were delineated on planning-CT, including the parotid, submandibular and sublingual glands and the minor glands in the soft palate, buccal mucosa and lips. Patients with moderate-to-severe xerostomia or moderate-to-severe sticky saliva, respectively, at baseline were excluded. In order to determine which salivary glands were most important, a multivariate logistic regression analysis with an extended bootstrapping technique was used. Results: In total, 29% and 19% of the cases suffered from XER day and XER night , respectively. The multivariate analysis showed that baseline xerostomia and the mean parotid gland dose were the most important predictors for XER day and XER night . At 6 months after (CH)RT, 10% and 12% of the cases reported STIC day and STIC night respectively. We were not able to identify prognostic factors related to dose distributions with regard to STIC day . The mean submandibular gland dose was associated with STIC night

  15. Generation of linearly polarized resonant transition radiation X-ray beam

    International Nuclear Information System (INIS)

    Yajima, Kazuaki; Awata, Takaaki; Ikeda, Mitsuharu; Ikeda, Kenichi; Yogo, Akifumi; Itoh, Akio; Imanishi, Nobutsugu

    2000-01-01

    We have proposed a method to generate almost linearly polarized resonant transition radiation X rays by using a rectangular slit placed on an electron beam axis. Our calculation predicted that the linearity is 93.5% for the resonant transition radiation X-ray beam extracted through a slit of 0.5 mrad long and 0.2 mrad wide in case of 1-GeV electron beam irradiating a 7.5-μm thick Kapton foil stack. (author)

  16. Generation of linearly polarized resonant transition radiation X-ray beam

    Energy Technology Data Exchange (ETDEWEB)

    Yajima, Kazuaki; Awata, Takaaki; Ikeda, Mitsuharu; Ikeda, Kenichi; Yogo, Akifumi; Itoh, Akio; Imanishi, Nobutsugu [Kyoto Univ. (Japan). Dept. of Nuclear Engineering

    2000-03-01

    We have proposed a method to generate almost linearly polarized resonant transition radiation X rays by using a rectangular slit placed on an electron beam axis. Our calculation predicted that the linearity is 93.5% for the resonant transition radiation X-ray beam extracted through a slit of 0.5 mrad long and 0.2 mrad wide in case of 1-GeV electron beam irradiating a 7.5-{mu}m thick Kapton foil stack. (author)

  17. A simple method of dosimetry for E-beam radiation

    International Nuclear Information System (INIS)

    Spencer, D.S.; Thalacker, V.P.; Chasman, J.N.; Siegel, S.

    1985-01-01

    A simple method utilizing a photochromic 'intensity label' for monitoring electron-beam sources was evaluated. The labels exhibit a color change upon exposure to UV or e-beam radiation. A correlation was found between absorbed energy and Gardner Color Index at low electron-beam doses. (author)

  18. Application of electron beam for preparation of membranes

    International Nuclear Information System (INIS)

    Mohamed Mahmoud Nasef

    2004-01-01

    Membranes have generated considerable interest in a number of technologically significant fields, such as chemical, biochemical and biomedical engineering. However, it becomes important to design and develop particular membranes for specific applications. Radiation induced grafting of hydrophilic monomers into polymeric films has been found to be an appealing method for producing various membranes. The method has the flexibility of using various types of radiation, such as γ-rays, electron beam, and plasma, irrespective of the shape and size of the polymer. Of all, electron beam accelerator is an advantageous source of high-energy radiations that can initiate grafting reactions required for preparation of membranes particularly when pilot production and commercial applications are sought. The grafting penetration can be varied from surface to bulk of membranes by applying acceleration energy. This article briefly reviews the use of electron beam radiation to prepare various membranes by radiation induced grafting of vinyl and acrylic monomers onto polymer films. Some basic fundamentals of radiation induced grafting and advantages of electron beam over Co-60 are highlighted. Potential applications of radiation-grafted membranes in various fields are also surveyed. (author)

  19. Disinfestation of agricultural products with electron beams and their radiation tolerance

    International Nuclear Information System (INIS)

    Hayashi, Toru

    1996-01-01

    Some agricultural products contaminated with insect pests are fumigated with methyl bromide for quarantine purposes. However, the use of methyl bromide is preferably restricted because of its ozone depleting effect. Therefore, establishing alternative quarantine techniques is highly desirable; one such technique is exposure to ionizing radiation. Few data are available on the effects of radiation on insect pests other than fruit flies and stored-product insects and on the radiation tolerance of host commodities. Radiation technology as an alternative to methyl bromide fumigation will be used to inactivate not only insects but also mites, spider mites, thrips, nematodes, scales, mealybugs and thrips contaminating fruits, grains, cut flowers, vegetables, timbers, seedlings and seeds. In order to collect data on the effects of irradiation on pests and host commodities, IAEA and FAO have conducted an international project, 'FAO/IAEA Coordinated Research Programme on Irradiation as a Quarantine Treatment of Mites, Nematodes and Insects other than Fruit Fly' since 1992. The project determines the minimum doses necessary to inactivate pests and the maximum doses host commodities tolerate. All pests except nematodes can be inactivated at doses 400Gy or lower. Various varieties of cut flowers and herbs are tolerant to 400Gy of radiation, although some flowers and herbs such as chrysanthemum, rose, lily, calla, anthurium, sweet pea, iris, dill, basil and arugula are intolerant to 200Gy of radiation. Japanese research project on treatment of cut flowers with electron beams carried out mainly by Yokohama Plant Protection Station greatly contributes to these conclusions. Aqueous solution (2%) of sucrose, glucose, fructose or maltose prevents radiation-induced detrimental effects of radiation on chrysanthemums. Sugars reduce radiation-induced physiological deterioration of chrysanthemums. (author)

  20. Radiation-induced apoptosis

    International Nuclear Information System (INIS)

    Ohyama, Harumi

    1995-01-01

    Apoptosis is an active process of gene-directed cellular self-destruction that can be induced in many cell types via numerous physiological and pathological stimuli. We found that interphasedeath of thymocytes is a typical apoptosis showing the characteristic features of apoptosis including cell shrinkage, chromatin condensation and DNA degradation. Moderate dose of radiation induces extensive apoptosis in rapidly proliferating cell population such as the epithelium of intestinal crypt. Recent reports indicate that the ultimate form of radiation-induced mitotic death in several cells is also apoptosis. One of the hallmarks of apoptosis is the enzymatic internucleosomal degradation of chromatin DNA. We identified an endonuclease responsible for the radiation-induced DNA degradation in rat thymocytes. The death-sparing effects of interrupting RNA and protein synthesis suggested a cell genetic program for apoptosis. Apoptosis of thymocytes initiated by DNA damage, such as radiation and radio mimetic substance, absolutely requires the protein of p53 cancer suppresser gene. The cell death induced by glucocorticoid, or aging, has no such requirement. Expression of oncogene bcl-2 rescues cells from the apoptosis. Massive apoptosis in radiosensitive cells induced by higher dose radiation may be fatal. It is suggested that selective apoptotic elimination of cells would play an important role for protection against carcinogenesis and malformation through removal of cells with unrepaired radiation-induced DNA damages. Data to evaluate the significance of apoptosis in the radiation risk are still poor. Further research should be done in order to clarify the roles of the cell death on the acute and late effects of irradiation. (author)

  1. Radiation-beam technologies of structural materials treatment

    International Nuclear Information System (INIS)

    Kalin, B.A.

    2001-01-01

    Considered in the paper are the most advanced and prospective radiation-beam technologies (RBT) for treatment of structural materials, as applied to modifying the structural-phase state in the surface layers of half-finished products and articles with the purpose to improve their service properties. Ion-beam, plasma, and ion-plasma, as well as the technologies based on the use of concentrated fluxes of energy, generated by laser radiation, high-power pulsed electron and ion beams, and high-temperature pulsed plasma fluxes are analysed. As applied to improvement of the corrosion and erosion resistance, breaking strength, friction and wear resistance, and crack resistance, the directions of the choice and the use of RBT have been considered for changes of the surface layer state by applying covers and films, and by a change of the surface topography (relief), surface structure and defects, and the element composition and phase state of materials [ru

  2. Study of hard braking x-ray radiation on the radiation-beam complex ''TEMP''

    International Nuclear Information System (INIS)

    Batrakov, A.B.; Glushko, E.G.; Egorov, A.M.; Zinchenko, A.A.; Litvinenko, V.V.; Lonin, Yu.F.; Ponomarev, A.G.; Rybka, A.V.; Fedotov, S.I.; Uvarov, V.T.

    2015-01-01

    A calculation over of basic parameters of the hard brake x-rayed radiation for the microsecond accelerating of relativistic electronic beam T EMP . Optimization of converters is conducted for these aims. Maximal doses are experimentally got brake x-rayed radiation on beam-radiation complex T EMP . The diagrams of orientation of the brake x-rayed radiation are taken off depending on energies of bunches and forms of electrodes.

  3. A randomized, double-blind, placebo-controlled trial of a traditional herbal formula, Yukmijihwang-tang in elderly subjects with xerostomia.

    Science.gov (United States)

    Han, Gajin; Ko, Seok-Jae; Kim, Juyeon; Oh, Ja-Young; Park, Jae-Woo; Kim, Jinsung

    2016-04-22

    Yukmijihwang-tang (YMJ) is a typical herbal formula to treat Yin-deficiency (YD) syndrome by enriching the fluid-humor of the body. YMJ has been used to treat dry mouth symptoms for hundreds of years in traditional East Asian medicine. Xerostomia, a subjective oral dryness, is common in the elderly and results in impaired quality of life. Many conventional treatments for xerostomia provide only temporary symptom relief, and have side effects. The aim of this study is to investigate the efficacy and safety of YMJ for the treatment of xerostomia in the elderly. This study was designed as a randomized, placebo-controlled, double-blinded, two center trial. Ninety-six subjects aged 60-80 years who had experienced xerostomia for at least 3 months and presented with score>40 on the visual analog scale (VAS) for subjective oral dryness were recruited and randomly allocated to YMJ and placebo groups. YMJ or placebo was administered to each group for 8 weeks (3g of YMJ or placebo, three times per day). The primary outcome was change of VAS for xerostomia from 0 to 8 weeks. VAS for xerostomia was decreased by 22.04±22.76 in the YMJ group and 23.58±23.04 in the placebo group. YMJ had no effect on xerostomia. However, participants with BMIs lower than 29.37kg/m(2) showed improvement of xerostomia after 8 weeks of treatment with YMJ compared to placebo. In addition, YMJ improved oral moisture, which is associated with subjective oral dryness in the YMJ group, and the relationship between VAS for xerostomia and YD was significant. A trend was observed in which YMJ improved oral moisture status and subjective oral dryness in elderly subjects with lower BMI and greater tendency toward YD. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  4. A case of xerostomia caused by exposure to radioactive iodine

    International Nuclear Information System (INIS)

    Kusafuka, Yuji; Kamata, Takahiro; Nakanishi, Yoshitaka; Kurita, Hiroshi; Sakai, Hironori

    2012-01-01

    Oral radioiodine ( 131 I) therapy is known to be an effective treatment for differentiated thyroid carcinoma, but it can cause salivary gland impairment. We report a case of xerostomia caused by oral radioiodine therapy for thyroid cancer. A 47-year-old woman consulted our hospital because of tongue pain accompanied by xerostomia. The patient had a history of receiving radioiodine therapy for metastatic thyroid carcinoma 3 times (total 9,990 MBq). Clinical examination demonstrated oral dryness and reduced salivary gland function. On the gum test, the salivary flow was 2 ml in 6 minutes. It was hard to continue chewing for more than 6 minutes because of irritation. A computed tomographic scan showed atrophic changes of both parotid glands. On radioiodine whole-body imaging, uptake of radioiodine was evident in both the parotid and submandibular glands. Based on these findings, xerostomia caused by salivary gland injury due to radioiodine therapy was clinically diagnosed. The salivary gland injury was irreversible, and the patient received symptomatic therapy and pilocarpine hydrochoride. Early intervention to avoid salivary gland injury is important in patients who receive radioactive iodine therapy. (author)

  5. Design, construction and characterization of special ionization chambers for X radiation beams monitoring

    International Nuclear Information System (INIS)

    Yoshizumi, Maira Tiemi

    2010-01-01

    X radiation equipment may show fluctuations in the radiation beam intensity, as they are connected to the power net. These intensity variations can, in turn, modify the air kerma rate produced by this radiation beam. In a calibration laboratory, where radiation detectors (from clinics and hospital services) are calibrated, variations in the radiation beam intensity may cause an error in the absorbed dose determination. The monitor ionization chambers are used to verify the radiation beam intensity constancy, and to provide a correction for possible fluctuations. In this work, monitor ionization chambers for X radiation beams were designed, assembled and characterized. The developed ionization chambers have an innovative design, ring-shaped, with aluminium or graphite electrodes. These ring-shaped ionization chambers have the advantage of not interfering in the direct radiation beams. A double-volume ionization chamber with graphite electrodes was also developed. This ionization chamber is similar to the commercial monitor ionization chamber used in the Calibration Laboratory of the Instituto de Pesquisas Energeticas e Nucleares. All developed ionization chambers were tested in several standardized radiation beams and their performances were compared with those of commercial ionization chambers. The results show that two of the four ionization chambers developed showed performance comparable to that of the commercial ionization chambers tested. Besides presenting good results, the ionization chambers were designed and manufactured using low cost materials, which are easily found on the Brazilian market. (author)

  6. Oral health Status, Medical History, Xerostomia dan Quality of Life of elderly In Luwu Timur, Sulawesi Selatan

    OpenAIRE

    Samad, Rasmidar

    2013-01-01

    Xerostomia is a common condition in elderly people which may result in permanent impairtment that would be one risk factor for decreased quality of life Objective the aim of this study is to determine the relathionship of sociodemographic status, medical history, xerostomia, tooth loss and caries status with quality of life of elderly in luwu timur Xerostomia is a common condition in elderly people which may result in permanent impairtment that would be one risk factor for decreased qua...

  7. Radiation processing of carrageenan using electron beam

    International Nuclear Information System (INIS)

    Abad, L.V.; Aranilla, C.T.; Relleve, L.; Dela Rosa, A.M.

    2005-01-01

    Electron beam accelerator has been widely employed in the modification of natural polymers for the development of materials used in biomedical and agricultural applications. The carrageenans are among these materials that show a vast potential for these types of applications. Previous studies at the Philippine Nuclear Research Institute focused on the utilization of gamma radiation to modify the carrageenans. Radiation degradation of carrageenan found valuable use as plant growth promoter. Hydrogels for burn dressing using blends of carrageenan and synthetic polymers have also been made using gamma radiation. While previous studies have been focused on the use of gamma radiation to modify the carrageenans, recent studies expanded the technology to electron beam. Concretely, researches are along the following two areas: a) Degradation studies of aqueous carrageenan using the LEEB and b) Preparation of blend polysaccharide derivatives such as carboxymethylcellulose (CMC), and hydroxypropylcellulose (HPC) with kappa-carrageenan (KC) by EB radiation. These works were done at the Takasaki Radiation Chemistry Research Establishment (TRCRE) by two PNRI colleagues under the nuclear researcher exchange program of the Japan Ministry of Education, Culture, Sports, Science and Technology (MEXT). The first area had already been reported and discussed in the last project meeting held in Malaysia. (author)

  8. Beam induced rf cavity transient voltage

    International Nuclear Information System (INIS)

    Kramer, S.L.; Wang, J.M.

    1998-10-01

    The authors calculate the transient voltage induced in a radio frequency cavity by the injection of a relativistic bunched beam into a circular accelerator. A simplified model of the beam induced voltage, using a single tone current signal, is generated and compared with the voltage induced by a more realistic model of a point-like bunched beam. The high Q limit of the bunched beam model is shown to be related simply to the simplified model. Both models are shown to induce voltages at the resonant frequency ω r of the cavity and at an integer multiple of the bunch revolution frequency (i.e. the accelerating frequency for powered cavity operation) hω ο . The presence of two nearby frequencies in the cavity leads to a modulation of the carrier wave exp(hω ο t). A special emphasis is placed in this paper on studying the modulation function. These models prove useful for computing the transient voltage induced in superconducting rf cavities, which was the motivation behind this research. The modulation of the transient cavity voltage discussed in this paper is the physical basis of the recently observed and explained new kinds of longitudinal rigid dipole mode which differs from the conventional Robinson mode

  9. Imaging and characterization of primary and secondary radiation in ion beam therapy

    Energy Technology Data Exchange (ETDEWEB)

    Granja, Carlos, E-mail: carlos.granja@utef.cvut.cz; Opalka, Lukas [Institute of Experimental and Applied Physics, Czech Technical University in Prague (Czech Republic); Martisikova, Maria; Gwosch, Klaus [German Cancer Research Center, Heidelberg (Germany); Jakubek, Jan [Advacam, Prague (Czech Republic)

    2016-07-07

    Imaging in ion beam therapy is an essential and increasingly significant tool for treatment planning and radiation and dose deposition verification. Efforts aim at providing precise radiation field characterization and online monitoring of radiation dose distribution. A review is given of the research and methodology of quantum-imaging, composition, spectral and directional characterization of the mixed-radiation fields in proton and light ion beam therapy developed by the IEAP CTU Prague and HIT Heidelberg group. Results include non-invasive imaging of dose deposition and primary beam online monitoring.

  10. Influence of beam divergence on form-factor in X-ray diffraction radiation

    International Nuclear Information System (INIS)

    Sergeeva, D.Yu.; Tishchenko, A.A.; Strikhanov, M.N.

    2015-01-01

    Diffraction radiation from divergent beam is considered in terms of radiation in UV and X-ray range. Scedastic form of Gaussian distribution of the particle in the bunch, i.e. Gaussian distribution with changing dispersion has been used, which is more adequate for description of divergent beams than often used Gaussian distribution with constant dispersion. Both coherent and incoherent form-factors are taken into account. The conical diffraction effect in diffraction radiation is proved to make essential contribution in spectral-angular characteristics of radiation from a divergent beam

  11. Imaging and characterization of primary and secondary radiation in ion beam therapy

    International Nuclear Information System (INIS)

    Granja, Carlos; Opalka, Lukas; Martisikova, Maria; Gwosch, Klaus; Jakubek, Jan

    2016-01-01

    Imaging in ion beam therapy is an essential and increasingly significant tool for treatment planning and radiation and dose deposition verification. Efforts aim at providing precise radiation field characterization and online monitoring of radiation dose distribution. A review is given of the research and methodology of quantum-imaging, composition, spectral and directional characterization of the mixed-radiation fields in proton and light ion beam therapy developed by the IEAP CTU Prague and HIT Heidelberg group. Results include non-invasive imaging of dose deposition and primary beam online monitoring.

  12. [Xerostomia and its impact on oral health-related quality of life].

    Science.gov (United States)

    Herrmann, Gianna; Müller, Karolina; Behr, Michael; Hahnel, Sebastian

    2017-02-01

    Dry mouth is a frequently occurrence in elderly people and causes numerous clinical and social problems. To investigate the quality of life in geriatric patients living in nursing homes depending on the subjective sensation of dry mouth and associated oral parameters. A total of 62 male and female elderly patients living in 7 cooperating nursing homes were interviewed employing questionnaires with regard to their oral health-related quality of life (GOHAI) and their subjective perception of dry mouth (sXI-D). Dental status, drinking habits and current medication were documented. The mean GOHAI score was 53.6 and the mean sXI-D score was 7.9. Oral health-related quality of life was significantly influenced by the subjective sensation of dry mouth (p Xerostomia was significantly influenced by the number of medications consumed (p = 0.039). Xerostomia has a significant impact on the oral health-related quality of life of elderly people living in nursing homes. Thus, dental treatment should focus on the alleviation of xerostomia to improve the oral health-related quality of life in the elderly population.

  13. ALICE Transition Radiation Detector (TRD), test beam.

    CERN Multimedia

    2003-01-01

    Electrons and positrons can be discriminated from other charged particles using the emission of transition radiation - X-rays emitted when the particles cross many layers of thin materials. To develop such a Transition Radiation Detector(TRD) for ALICE many detector prototypes were tested in mixed beams of pions and electrons, as in the example shown here.

  14. [Dynamic observation on the short-term change of xerostomia after intensity-modulated radiotherapy for patients with nasopharyngeal carcinoma].

    Science.gov (United States)

    Li, Yanjie; Zhao, Changqing

    2015-01-01

    To dynamically analyze the change of xerostomia in patients with nasopharyngeal carcinoma after radiotherapy by DW MRI. Twenty-three nasopharyngeal carcinoma patients confirmed by pathology were enrolled. Male/Female: 19/4. The age was from 37 to 69 years. The patients were divided into two groups: G1, Dmeanxerostomia was assessed. SPSS 13.0 and SAS 8.2 software were used to analyze the data. At the end of IMRT, the change tendency of ADC in parotid and submandibular glands value was different in patients with different degree of xerostomia (F = 11.52, P xerostomia could be found in patients within different irradiation dose groups (Z = -3.622, P xerostomia for patients at the end of IMRT (Z value was -0.791, -0.949, 2.488, all P > 0.05). A significant difference of xerostomia degree in patients was found at the various follow-up time after IMRT (χ(2) = 19.59, P xerostomia in patients with nasopharyngeal carcinoma after radiotherapy. The degrees of salivary gland function and dry mouth in patients with nasopharyngeal carcinoma damage evaluate with illuminated dose increases. The function of salivary gland gradually restored and the degree of dry mouth gradually reduce with the extension of time after radiotherapy.

  15. The role of adjuvant external beam radiation therapy for papillary thyroid carcinoma invading the trachea

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Suk; Choi, Jae Hyuck; Kim, Kwang Sik [Jeju National University Hospital, Jeju National University School of Medicine, Jeju (Korea, Republic of); and others

    2017-06-15

    To evaluate the effect of adjuvant external beam radiation therapy (EBRT) on local failure-free survival rate (LFFS) for papillary thyroid cancer (PTC) invading the trachea. Fifty-six patients with locally advanced PTC invading the trachea were treated with surgical resection. After surgery, 21 patients received adjuvant EBRT and radioactive iodine therapy (EBRT group) and 35 patients were treated with radioactive iodine therapy (control group). The age range was 26–87 years (median, 56 years). The median follow-up period was 43 months (range, 4 to 145 months). EBRT doses ranged from 50.4 to 66 Gy (median, 60 Gy). Esophagus invasion and gross residual disease was more frequent in the EBRT group. In the control group, local recurrence developed in 9 (9/35, 26%) and new distant metastasis in 2 (2/35, 6%) patients, occurring 4 to 68 months (median, 37 months) and 53 to 68 months (median, 60 months) after surgery, respectively. Two patients had simultaneous local recurrence and new distant metastasis. There was one local failure in the EBRT group at 18 months after surgery (1/21, 5%). The 5-year LFFS was 95% in the EBRT group and 63% in the control group (p = 0.103). In the EBRT group, one late grade 2 xerostomia was developed. Although, EBRT group had a higher incidence of esophagus invasion and gross residual disease, EBRT group showed a better 5-year LFFS. Adjuvant EBRT may have contributed to the better LFFS in these patients.

  16. Impact of clinical status and salivary conditions on xerostomia and oral health-related quality of life of adolescents with type 1 diabetes mellitus.

    Science.gov (United States)

    Busato, Ivana Maria Saes; Ignácio, Sérgio Aparecido; Brancher, João Armando; Moysés, Simone Tetu; Azevedo-Alanis, Luciana Reis

    2012-02-01

    To investigate the influence of clinical status and salivary conditions on the presence of xerostomia on adolescents with and without type 1 diabetes mellitus (DM1), and further to investigate the influence of clinical status, salivary conditions and xerostomia on oral health-related quality of life (OHQoL) of those with DM1. A cross-sectional study was performed on 102 adolescents, 51 with DM1 and 51 nondiabetics. Xerostomia was detected by asking a question about the sensation of having 'dry mouth', and Oral Health Impact Profile-14 was used to measure the impact of xerostomia on OHQoL. The clinical status was assessed by using decayed, missing or filled and Community Periodontal indices, and by evaluating oral manifestations; and the following salivary conditions were evaluated: stimulated salivary flow, pH, buffer capacity, total protein, amylase, urea, calcium, and glucose salivary concentrations. Multiple logistic regression analysis was used to evaluate the influence of clinical status and salivary conditions on xerostomia and the impact of xerostomia on the OHQoL of adolescents with DM1. Clinical status and salivary conditions was shown to have no influence on the presence of xerostomia. Bivariate (P = 0.00) and logistic regression (P = 0.01) analysis showed a significant association between DM1 and xerostomia. Logistic regression analysis showed association between xerostomia (P = 0.00) and OHQoL, and caries experience (P = 0.03) and OHQoL. DM1 showed to be predictive of a high prevalence of xerostomia in adolescents. Caries experience and xerostomia showed to have a negative impact on the OHQoL of adolescents with DM1. © 2011 John Wiley & Sons A/S.

  17. Type 1 diabetes mellitus, xerostomia, and salivary flow rates.

    Science.gov (United States)

    Moore, P A; Guggenheimer, J; Etzel, K R; Weyant, R J; Orchard, T

    2001-09-01

    The Oral Health Science Institute at the University of Pittsburgh has completed a cross-sectional epidemiologic study of 406 subjects with type 1 diabetes and 268 control subjects without diabetes that assessed the associations between oral health and diabetes. This report describes the prevalence of dry-mouth symptoms (xerostomia), the prevalence of hyposalivation in this population, and the possible interrelationships between salivary dysfunction and diabetic complications. The subjects with diabetes were participants in the Pittsburgh Epidemiology of Diabetes Complications study who were enrolled in an oral health substudy. Control subjects were spouses or best friends of participants or persons recruited from the community through advertisements in local newspapers. Assessments of salivary function included self-reported xerostomia measures and quantification of resting and stimulated whole saliva flow rates. Subjects with diabetes reported symptoms of dry mouth more frequently than did control subjects. Salivary flow rates were also impaired in the subjects with diabetes. Regression models of potential predictor variables were created for the 3 self-reported xerostomia measures and 4 salivary flow rate variables. Of the medical diabetic complications studied (ie, retinopathy, peripheral and autonomic neuropathy, nephropathy, and peripheral vascular disease), only neuropathy was found to be associated with xerostomia and decreased salivary flow measures. A report of dry-mouth symptoms was associated with current use of cigarettes, dysgeusia (report of a bad taste), and more frequent snacking behavior. Xerogenic medications and elevated fasting blood glucose concentrations were significantly associated with decreased salivary flow. Resting salivary flow rates less than 0.01 mL/min were associated with a slightly higher prevalence of dental caries. Subjects who reported higher levels of alcohol consumption were less likely to have lower rates of stimulated

  18. Impurity radiation from a beam-plasma neutron source

    International Nuclear Information System (INIS)

    Molvik, A.W.

    1995-01-01

    Impurity radiation, in a worst case evaluation for a beam-plasma neutron source (BPNS), does not limit performance. Impurities originate from four sources: (a) sputtering from walls by charge exchange or alpha particle bombardment, (b) sputtering from limiters, (c) plasma desorption of gas from walls and (d) injection with neutral beams. Sources (c) and (d) are negligible; adsorbed gas on the walls of the confinement chamber and the neutral beam sources is removed by the steady state discharge. Source (b) is negligible for impinging ion energies below the sputtering threshold (T i ≤ 0.025 keV on tungsten) and for power densities to the limiter within the capabilities of water cooling (30-40 MW/m 2 ); both conditions can be satisfied in the BPNS. Source (a) radiates 0.025 MW/m 2 to the neutron irradiation samples, compared with 5 to 10 MW/m 2 of neutrons; and radiates a total of 0.08 MW from the plasma column, compared with 60 MW of injected power. The particle bombardment that yields source (a) deposits an average of 2.7 MW/m 2 on the samples, within the capabilities of helium gas cooling (10 MW/m 2 ). An additional worst case for source (d) is evaluated for present day 2 to 5 s pulsed neutral beams with 0.1% impurity density and is benchmarked against 2XIIB. The total radiation would increase a factor of 1.5 to ≤ 0.12 MW, supporting the conclusion that impurities will not have a significant impact on a BPN. (author). 61 refs, 7 figs, 2 tabs

  19. Prevalence and factors associated with xerostomia and hyposalivation among community-dwelling older people in Japan.

    Science.gov (United States)

    Ohara, Yuki; Hirano, Hirohiko; Yoshida, Hideyo; Obuchi, Shuichi; Ihara, Kazushige; Fujiwara, Yoshinori; Mataki, Shiro

    2016-03-01

    This study investigated the prevalence and factors associated with xerostomia and hyposalivation among community-dwelling older people. Xerostomia and hyposalivation are common symptoms in the older population. This study included with 894 community-dwelling, Japanese older people (355 men, 539 women; age 65-84 years) who participated in a comprehensive geriatric health examination, which included questionnaires and interviews regarding medical history, medications, Tokyo Metropolitan Institute of Gerontology Index of Competence (TMIG-IC), depressive condition. The Zung Self-Rating Depression Scale (SDS) was used to evaluate depression. Resting salivary flow rate was evaluated by the modified cotton roll method. In this study, 34.8% of the participants (mean age, 73.5 ± 5.0 years) complained about xerostomia, while the prevalence of hyposalivation was 11.5%. Multiple regression analysis revealed hypnotics use [odds ratio (OR) = 1.71, 95% confidence interval (CI) = 1.13-2.61], SDS (OR = 1.05, CI = 1.04-1.07) and TMIG-IC total points (OR = 0.87, CI = 0.76-0.99) to be significantly associated with xerostomia. In contrast, female gender (OR = 2.59, CI = 1.55-4.31) and the use of agents affecting digestive organs (OR = 1.78, CI = 1.11-2.86) were associated with hyposalivation. Our findings showed that the prevalence of xerostomia and hyposalivation were approximately 1 in 3 and 1 in 10 respectively. The factors associated with psychological factors and high-level functional competence, while hyposalivation was associated with medications and gender, as well as systemic and/or metabolic differences. It is important to consider these multidimensional factors associated with xerostomia and hyposalivation. © 2013 John Wiley & Sons A/S and The Gerodontology Society. Published by John Wiley & Sons Ltd.

  20. Prevalence of xerostomia on type 2 diabetes mellitus in Hajj Hospital Surabaya

    Directory of Open Access Journals (Sweden)

    Kus Harijanti

    2007-09-01

    Full Text Available Diabetes Mellitus (DM is a chronic disorder of carbohydrate, fat and protein metabolism. A defective or deficient of the insulin secretory, which is translated into impaired carbohydrate (glucose use, is characteristic feature of DM, as the resultant is hyperglycemia. There is variability among patients, however, morphologic changes are likely found in arteries (atherosclerosis, basement membrane of the blood vessel wall tissues (micro angiopathy, kidneys (diabetic nephropathy, retina (retinopathy, nerves (neuropathy and other tissues. If it involves salivary glands, the clinical sign is xerostomia. The type 2 of DM is caused by a combination of peripheral resistance to insulin action and an inadequate secretory response of the pancreatic b-cell. Approximately 80% to 90% of patients have type 2 diabetes. The purpose of this study was to determine the prevalence of xerostomia and its relation with level of blood glucose in type 2 DM. The data was taken using cross sectional method on the diabetic patients of Internal Medicine clinic, Hajj Hospital Surabaya from February to March 2006. The result that showed among 50 samples of the type 2 DM, the prevalence of xerostomia were 38 patients (76%. Most of the patients (32 patients = 84% on bad regulation of DM with level of fasting glucose ≥ 126 mg/dl and level of post prandial glucose ≥ 180 mg/dl. The study showed that bad regulation of type 2 DM could develop complication on salivary glands, with xerostomia as the clinical sign.

  1. Salivary flow rate and xerostomia in patients with type I and II diabetes mellitus.

    Science.gov (United States)

    Hoseini, Amineh; Mirzapour, Ali; Bijani, Ali; Shirzad, Atena

    2017-09-01

    Diabetes mellitus is one of the most prevalent metabolic diseases, with complications such as decreased salivary flow rate and xerostomia. This study aimed to determine the salivary flow rate and xerostomia in type I and II diabetic patients in comparison with healthy controls. This case-control study was performed on diabetic patients of a private office in Babol, Iran, between May 2015 and October 2016. This study involved two study groups (type I and II diabetes, with 40 in each group) and two control groups (control I and II, with 35 in each group) which were age- and sex-matched with the related study groups. They were all selected through simple sampling. Unstimulated whole saliva was collected through Navazesh method and the salivary flow rate was measured (ml/min). Xerostomia was evaluated via Fox's test. Moreover, the patients' data were recorded including age, sex, disease duration, type of diabetes, fasting blood glucose (FBG) and HbA1C. The obtained data were statistically analyzed by using SPSS version 17. Independent-samples t-test, Chi-square, Pearson correlation and multiple comparison post-hoc tests were employed as appropriated. psalivary flow rate in type I diabetics (0.35±0.11 ml/min) was lower than that in control I (0.50±0.07 ml/min) (p=0.01). The same difference was observed between type II diabetics (0.37±0.13 ml/min) and control II groups (0.47±0.11 ml/min) (p=0.01). No significant difference was observed in the salivary flow rate between type I and II diabetics (p=0.345). Furthermore, xerostomia was higher in type I (2.70±2.50, 1.17±1.60) and II (2.65±2.20-1.62±1.50) diabetics compared with the related control groups (p=0.01), (p=0.02). Type I, II diabetic patients revealed lower salivary flow rate and higher xerostomia compared with healthy controls. The salivary flow rate and xerostomia had inverse correlation.

  2. Radiation-Induced Prompt Photocurrents in Microelectronics Physics

    CERN Document Server

    Dodd, P E; Buller, D L; Doyle, B L; Vizkelethy, G; Walsh, D S

    2003-01-01

    The effects of photocurrents in nuclear weapons induced by proximal nuclear detonations are well known and remain a serious hostile environment threat for the US stockpile. This report describes the final results of an LDRD study of the physical phenomena underlying prompt photocurrents in microelectronic devices and circuits. The goals of this project were to obtain an improved understanding of these phenomena, and to incorporate improved models of photocurrent effects into simulation codes to assist designers in meeting hostile radiation requirements with minimum build and test cycles. We have also developed a new capability on the ion microbeam accelerator in Sandia's Ion Beam Materials Research Laboratory (the Transient Radiation Microscope, or TRM) to supply ionizing radiation in selected micro-regions of a device. The dose rates achieved in this new facility approach those possible with conventional large-scale dose-rate sources at Sandia such as HERMES III and Saturn. It is now possible to test the phy...

  3. Factors determining radiation-induced mixing at interfaces

    International Nuclear Information System (INIS)

    Collins, R.

    1986-01-01

    A review is given of the principal mechanisms contributing to atomic mixing produced by ion beams at initially well-defined interfaces between solid phases. Their relative importance is discussed in the light of available experimental evidence, and a critical survey is given of current mathematical models. The case of a thin interior implant layer is included. Those aspects of surface sputtering of direct relevance to the construction of the mixing equations are examined. Mixing mechanisms considered are ballistic relocation, diffusion, radiation-induced segregation, and drifts induced by chemical affinities of the elements concerned, together with constraints on all these from packing (Kirkendall) effects. Ballistic terms are subdivided into direct-recoil and cascade contributions. A brief review is given of the established methods of modelling them by using relocation integral cross-sections, and also the limitations and advantages of their approximation by differential equations of Fokker-Planck (diffusion) type. Genuinely diffusive mechanisms involved are thermal and radiation-enhanced diffusion; the question of the most appropriate form of Fick's law to use in each case is considered. The packing effects may be modelled either as a lattice relaxation to be imposed following each radiation dose increment, or as a continuously computed reversed collective current of atoms. These two approaches are discussed. (author)

  4. Electron-beam-induced conduction in dielectrics

    Energy Technology Data Exchange (ETDEWEB)

    Acris, F C; Davies, P M; Lewis, T J [University Coll. of North Wales, Bangor (UK). School of Electronic Engineering Science

    1976-03-14

    A model for the enhanced conduction induced in dielectric films under electron bombardment while electrically stressed is discussed. It is assumed that the beam produces a virtual electrode at the end of its range in the dielectric and, as a consequence, the induced conduction is shown to depend on the properties of that part of the dielectric beyond the range of the beam. This model has also been discussed recently by Nunes de Oliviera and Gross. In the present treatment, it is shown how the model permits investigation of beam scattering and carrier generation and recombination processes. Experiments on electron-bombardment-induced conduction of thin (72 to 360 nm) films of anodic tantalum oxide are reported and it is shown that the theoretical model provides a very satisfactory explanation of all features of the results including the apparent threshold energy for enhanced conduction.

  5. Yukmijihwang-tang for the treatment of xerostomia in the elderly: study protocol for a randomized, double-blind, placebo-controlled, two-center trial.

    Science.gov (United States)

    Han, Gajin; Park, Jae-Woo; Ko, Seok-Jae; Son, Jihee; Seon, Jongki; Kim, Juyeon; Kim, Seulki; Yeo, Inkwon; Ryu, Bongha; Kim, Jinsung

    2013-09-03

    Xerostomia, a subjective sense of dry mouth, is not generally regarded a disease despite its high prevalence among the elderly, and therefore continues to impair affected patients' quality of life. In traditional Korean medicine, 'Yin-Deficiency' has been implicated in the pathogenesis of xerostomia among the elderly. Yukmijihwang-tang is a famous herbal prescription used to relieve 'Yin-Deficiency', and reportedly has antioxidant effects; therefore, it is postulated that Yukmijihwang-tang can be used to treat xerostomia in the elderly. However, to our knowledge, no clinical trial has been conducted on the effects of Yukmijihwang-tang on xerostomia. Thus, we designed a randomized clinical trial to investigate the effects and safety of Yukmijihwang-tang on xerostomia in the elderly. In addition, we will clarify the aforementioned assumption that 'Yin-Deficiency' is the major cause of xerostomia in the elderly by identifying a correlation between xerostomia and 'Yin-Deficiency'. This randomized, double-blind, placebo-controlled trial will be carried out at two centers: Kyung Hee University Korean Medicine Hospital and Kyung Hee University Hospital at Gangdong. We will recruit 96 subjects aged 60-80 years who have experienced xerostomia for 3 months prior to participation. Subjects who present with score >40 on the visual analogue scale for xerostomia and unstimulated salivary flow rate under 0.3mL/min will be included and the randomization will be carried out by an independent statistician by using a random number creation program. The subjects and all researchers except the statistician will be blinded to the group assignment. Yukmijihwang-tang or placebo will be administered to each group for 8 weeks. The primary outcome is change in the scores for the visual analogue scale for xerostomia and the dry mouth symptom questionnaire from 0 to 8 weeks. It will be assessed whether Yukmijihwang-tang can be used as a new herbal treatment for xerostomia in the elderly by

  6. Performance of a pencil ionization chamber in various radiation beams

    International Nuclear Information System (INIS)

    Maia, A.F.; Caldas, L.V.E.

    2003-01-01

    Pencil ionization chambers were recommended for use exclusively in the computed tomography (CT) dosimetry, and, from the start, they were developed only with this application in view. In this work, we studied the behavior of a pencil ionization chamber in various radiation beams with the objective of extending its application. Stability tests were performed, and calibration coefficients were obtained for several standard radiation qualities of the therapeutical and diagnostic levels. The results show that the pencil ionization chamber can be used in several radiation beams other than those used in CT

  7. Localized surface grafting reactions on carbon nanofibers induced by gamma and e-beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Evora, M.C., E-mail: cecilia@ieav.cta.br [Institute for Advanced Studies-IEAV/DCTA, Av. Cel Jose Alberto Albano do Amarante, 1-Putim, 12228-001 São Jose dos Campos, SP (Brazil); Araujo, J.R., E-mail: jraraujo@inmetro.gov.br [Instituto Nacional de Metrologia, Qualidade e Tecnologia, Av. Nossa Sra. das Graças, 50, 25250-020 Duque de Caxias, RJ (Brazil); Ferreira, E.H.M. [Instituto Nacional de Metrologia, Qualidade e Tecnologia, Av. Nossa Sra. das Graças, 50, 25250-020 Duque de Caxias, RJ (Brazil); Strohmeier, B.R. [Thermo Fisher Scientific, 5225 Verona Road, Madison, WI 53711 (United States); Silva, L.G.A., E-mail: lgasilva@ipen.br [Institute for Nuclear and Energy Research- IPEN, Av. Prof lineu Prestes, 2242- Cidade Universitaria, 05508-000 SP (Brazil); Achete, C.A. [Instituto Nacional de Metrologia, Qualidade e Tecnologia, Av. Nossa Sra. das Graças, 50, 25250-020 Duque de Caxias, RJ (Brazil)

    2015-04-30

    Graphical abstract: - Highlights: • Methodology for the functionalization of carbon nanofibers was investigated. • Two radiation sources were used to promote grafting reactions: gamma and electron beam. • We report the optimum inhibitor concentration to achieve the functionalization. • Surface of carbon nanofibers showed an increase of oxygen content after irradiation. • The radiation-induced graphitization did not damage the overall sp{sup 2} structure. - Abstract: Electron beam and gamma-ray irradiation have potential application to modify the carbon fiber nanostructures in order to produce useful defects in the graphitic structure and create reactive sites. In this study, the methodology to functionalize carbon nanofiber (CNF), via a radiation process and using acrylic acid as a source of oxygen functional groups, was investigated. The samples were submitted to a direct grafting radiation process with electron beam and gamma-ray source. Several parameters were changed such as: acrylic acid concentration, radiation dose and percentage of inhibitor necessary to achieve functionalization, with higher percentage of oxygen functional groups on CNF surface, and better dispersion. The better results achieved were when mixing CNF in a solution of acrylic acid with 6% of inhibitor (FeSO{sub 4}·7H{sub 2}O) and irradiated at 100 kGy. The samples were characterized by X-ray photoelectron spectroscopy and the surface composition (atomic%) showed a significant increase of oxygen content for the samples after irradiation. Also, the dispersion of the functionalized CNF in water was stable during months which may be a good indication that the functionalization process of CNF via ionizing radiation was successful.

  8. Localized surface grafting reactions on carbon nanofibers induced by gamma and e-beam irradiation

    International Nuclear Information System (INIS)

    Evora, M.C.; Araujo, J.R.; Ferreira, E.H.M.; Strohmeier, B.R.; Silva, L.G.A.; Achete, C.A.

    2015-01-01

    Graphical abstract: - Highlights: • Methodology for the functionalization of carbon nanofibers was investigated. • Two radiation sources were used to promote grafting reactions: gamma and electron beam. • We report the optimum inhibitor concentration to achieve the functionalization. • Surface of carbon nanofibers showed an increase of oxygen content after irradiation. • The radiation-induced graphitization did not damage the overall sp 2 structure. - Abstract: Electron beam and gamma-ray irradiation have potential application to modify the carbon fiber nanostructures in order to produce useful defects in the graphitic structure and create reactive sites. In this study, the methodology to functionalize carbon nanofiber (CNF), via a radiation process and using acrylic acid as a source of oxygen functional groups, was investigated. The samples were submitted to a direct grafting radiation process with electron beam and gamma-ray source. Several parameters were changed such as: acrylic acid concentration, radiation dose and percentage of inhibitor necessary to achieve functionalization, with higher percentage of oxygen functional groups on CNF surface, and better dispersion. The better results achieved were when mixing CNF in a solution of acrylic acid with 6% of inhibitor (FeSO 4 ·7H 2 O) and irradiated at 100 kGy. The samples were characterized by X-ray photoelectron spectroscopy and the surface composition (atomic%) showed a significant increase of oxygen content for the samples after irradiation. Also, the dispersion of the functionalized CNF in water was stable during months which may be a good indication that the functionalization process of CNF via ionizing radiation was successful

  9. Beam Size Measurement by Optical Diffraction Radiation and Laser System for Compton Polarimeter

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Chuyu [Peking Univ., Beijing (China)

    2012-12-31

    Beam diagnostics is an essential constituent of any accelerator, so that it is named as "organs of sense" or "eyes of the accelerator." Beam diagnostics is a rich field. A great variety of physical effects or physical principles are made use of in this field. Some devices are based on electro-magnetic influence by moving charges, such as faraday cups, beam transformers, pick-ups; Some are related to Coulomb interaction of charged particles with matter, such as scintillators, viewing screens, ionization chambers; Nuclear or elementary particle physics interactions happen in some other devices, like beam loss monitors, polarimeters, luminosity monitors; Some measure photons emitted by moving charges, such as transition radiation, synchrotron radiation monitors and diffraction radiation-which is the topic of the first part of this thesis; Also, some make use of interaction of particles with photons, such as laser wire and Compton polarimeters-which is the second part of my thesis. Diagnostics let us perceive what properties a beam has and how it behaves in a machine, give us guideline for commissioning, controlling the machine and indispensable parameters vital to physics experiments. In the next two decades, the research highlight will be colliders (TESLA, CLIC, JLC) and fourth-generation light sources (TESLA FEL, LCLS, Spring 8 FEL) based on linear accelerator. These machines require a new generation of accelerator with smaller beam, better stability and greater efficiency. Compared with those existing linear accelerators, the performance of next generation linear accelerator will be doubled in all aspects, such as 10 times smaller horizontal beam size, more than 10 times smaller vertical beam size and a few or more times higher peak power. Furthermore, some special positions in the accelerator have even more stringent requirements, such as the interaction point of colliders and wigglor of free electron lasers. Higher performance of these accelerators increases the

  10. Beam Size Measurement by Optical Diffraction Radiation and Laser System for Compton Polarimeter

    International Nuclear Information System (INIS)

    Liu, Chuyu

    2012-01-01

    Beam diagnostics is an essential constituent of any accelerator, so that it is named as 'organs of sense' or 'eyes of the accelerator.' Beam diagnostics is a rich field. A great variety of physical effects or physical principles are made use of in this field. Some devices are based on electro-magnetic influence by moving charges, such as faraday cups, beam transformers, pick-ups; Some are related to Coulomb interaction of charged particles with matter, such as scintillators, viewing screens, ionization chambers; Nuclear or elementary particle physics interactions happen in some other devices, like beam loss monitors, polarimeters, luminosity monitors; Some measure photons emitted by moving charges, such as transition radiation, synchrotron radiation monitors and diffraction radiation-which is the topic of the first part of this thesis; Also, some make use of interaction of particles with photons, such as laser wire and Compton polarimeters-which is the second part of my thesis. Diagnostics let us perceive what properties a beam has and how it behaves in a machine, give us guideline for commissioning, controlling the machine and indispensable parameters vital to physics experiments. In the next two decades, the research highlight will be colliders (TESLA, CLIC, JLC) and fourth-generation light sources (TESLA FEL, LCLS, Spring 8 FEL) based on linear accelerator. These machines require a new generation of accelerator with smaller beam, better stability and greater efficiency. Compared with those existing linear accelerators, the performance of next generation linear accelerator will be doubled in all aspects, such as 10 times smaller horizontal beam size, more than 10 times smaller vertical beam size and a few or more times higher peak power. Furthermore, some special positions in the accelerator have even more stringent requirements, such as the interaction point of colliders and wigglor of free electron lasers. Higher performance of these accelerators increases the

  11. Relationship among perceived stress, xerostomia, and salivary flow rate in patients visiting a saliva clinic.

    Science.gov (United States)

    Bulthuis, Marjolein S; Jan Jager, Derk H; Brand, Henk S

    2018-03-09

    This aimed to assess the potential role of chronic stress in saliva secretion, xerostomia, and oral health in a population attending a saliva clinic. Data of 114 patients who met the inclusion criteria and completed all questionnaires were analyzed in this study. Participants completed several validated questionnaires, including the Perceived Stress Scale, the Oral Health Impact Profile (OHIP-14), Xerostomia Inventory (XI), and Bother xerostomia Index (BI). Subsequently, the unstimulated, chewing-stimulated, and citric acid-stimulated saliva secretion rates were determined gravimetrically. Data were evaluated using Spearman's correlation analysis and the Mann-Whitney U test. A significant correlation was observed between perceived stress and XI score (r = 0.312, p = 0.001), as well as between perceived stress and BI score (r = 0.334, p = 0.001). Stress levels also were significantly associated with OHIP-14 scores (r = 0.420, p stress and salivary flow rate could not be established. In this population, perceived chronic stress seems to be related to several aspects of dry mouth, including the perception of dry mouth, suffering from dry mouth, and the impact on quality of life. These effects were independent of the use of psychotropic medication. No actual reduction in salivary flow was found. Further studies to explore the causal linkage of stress with xerostomia seem warranted. Perceived chronic stress seems to be related with several aspects of dry mouth. This finding might be relevant in future prevention and treatment of xerostomia.

  12. Derivation of quantitative parameters from salivary scintigraphy and their utility in the diagnosis of xerostomia

    International Nuclear Information System (INIS)

    Booker, J.A.; Sutherland, D.C.; Howarth, D.M.; Taylor, L.; Tan, P.

    2002-01-01

    Full text: Xerostomia may be due to salivary dysfunction from a variety of causes and can be clinically variable ranging from halitosis to overt xerostomia. Semi-quantitative indices may be derived from salivary scintigraphy and may aid both clinical diagnosis and response to treatment. The objective of this study was to determine whether semi-quantitative indices were able to distinguish normal from abnormal salivary function and to be clinically useful. 56 consecutive patients with xerostomia (including a subset of 10 patients with clinical Sjogrens syndrome) and 25 healthy volunteers underwent salivary scintigraphy. Semi-quantitative analysis of time activity curves was performed deriving 6 different indices for each of the four major salivary glands. These indices included percent uptake (%UP), uptake ratios(UR),maximum accumulation (MA), pre-stimulatory oral radioactivity index (PRI), post-stimulatory oral radioactivity index (POI) and ejection fraction (EF). The 95% confidence interval around the mean values was used to compare normal volunteers and xerostomia patients. Wide reference limits were obtained for all indices derived from normal volunteers. No significant difference was found between normal volunteers and patients using any of the six indices. UR and EF showed the greatest difference between the groups. Allowing for Type Two (Beta) error, none of the above indices allow patients with xerostomia who have salivary dysfunction to be distinguished from normal subjects. Copyright (2002) The Australian and New Zealand Society of Nuclear Medicine Inc

  13. Parotid gland shrinkage during IMRT predicts the time to Xerostomia resolution.

    Science.gov (United States)

    Sanguineti, Giuseppe; Ricchetti, Francesco; Wu, Binbin; McNutt, Todd; Fiorino, Claudio

    2015-01-17

    To assess the impact of mid-treatment parotid gland shrinkage on long term xerostomia during IMRT for oropharyngeal SCC. All patients treated with IMRT at a single Institution from November 2007 to June 2010 and undergoing weekly CT scans were selected. Parotid glands were contoured retrospectively on the mid treatment CT scan. For each parotid gland, the percent change relative to the planning volume was calculated and combined as weighted average. Patients were considered to be xerostomic if developed GR2+ dry mouth according to CTCAE v3.0. Predictors of the time to xerostomia resolution or downgrade to 1 were investigated at both uni- and multivariate analysis. 85 patients were selected. With a median follow up of 35.8 months (range: 2.4-62.6 months), the actuarial rate of xerostomia is 26.2% (SD: 5.3%) and 15.9% (SD: 5.3%) at 2 and 3 yrs, respectively. At multivariate analysis, mid-treatment shrink along with weighted average mean parotid dose at planning and body mass index are independent predictors of the time to xerostomia resolution. Patients were pooled in 4 groups based on median values of both mid-treatment shrink (cut-off: 19.6%) and mean WA parotid pl-D (cut-off: 35.7 Gy). Patients with a higher than median parotid dose at planning and who showed poor shrinkage at mid treatment are the ones with the outcome significantly worse (3-yr rate of xerostomia ≈ 50%) than the other three subgroups (3-yr rate of xerostomia ≈ 10%). For a given planned dose, patients whose parotids significantly shrink during IMRT are less likely to be long-term supplemental fluids dependent.

  14. Characterization of ion beam induced nanostructures

    International Nuclear Information System (INIS)

    Ghatak, J.; Satpati, B.; Umananda, M.; Kabiraj, D.; Som, T.; Dev, B.N.; Akimoto, K.; Ito, K.; Emoto, T.; Satyam, P.V.

    2006-01-01

    Tailoring of nanostructures with energetic ion beams has become an active area of research leading to the fundamental understanding of ion-solid interactions at nanoscale regime and with possible applications in the near future. Rutherford backscattering spectrometry (RBS), high resolution transmission electron microscopy (HRTEM) and asymmetric X-ray Bragg-rocking curve experimental methods have been used to characterize ion-induced effects in nanostructures. The possibility of surface and sub-surface/interface alloying at nano-scale regime, ion-beam induced embedding, crater formation, sputtering yield variations for systems with isolated nanoislands, semi-continuous and continuous films of noble metals (Au, Ag) deposited on single crystalline silicon will be reviewed. MeV-ion induced changes in specified Au-nanoislands on silicon substrate are tracked as a function of ion fluence using ex situ TEM. Strain induced in the bulk silicon substrate surface due to 1.5 MeV Au 2+ and C 2+ ion beam irradiation is determined by using HRTEM and asymmetric Bragg X-ray rocking curve methods. Preliminary results on 1.5 MeV Au 2+ ion-induced effects in nanoislands of Co deposited on silicon substrate will be discussed

  15. Significance and Implications of Patient-reported Xerostomia in Sjögren's Syndrome: Findings From the National Institutes of Health Cohort.

    Science.gov (United States)

    Billings, Monisha; Dye, Bruce A; Iafolla, Timothy; Baer, Alan N; Grisius, Margaret; Alevizos, Ilias

    2016-10-01

    Xerostomia is a chief complaint of patients with Sjögren's syndrome (SS). However, newer proposals for SS classification remove xerostomia and hyposalivation from the criteria list. Given these developments and the importance of patient-centered research outcomes, we sought to evaluate the utility of patient-reported xerostomia with implications for classification criteria, and clinical trials targeting SS treatment modalities. A nested case-control study was designed within The National Institute of Dental and Craniofacial Research/National Institutes of Health (NIDCR/NIH) SS Cohort - one of the largest SS cohorts in the US. Clinical characteristics of those with and without xerostomia in SS and other salivary gland dysfunctions were compared. Several analytical methods were employed, including multivariable logistic regression modeling. The NIDCR/NIH Sjögren's Syndrome Clinic has an open cohort with ongoing enrollment since 1984. This open cohort comprised of 2046 participants by August 27, 2015. Baseline data of 701 SS, 355 Sicca, and 247 ISS participants within the source cohort were analyzed. Xerostomia was highest among SS participants (87.4%, 95% CI: 84.8%-89.8%) compared to Sicca (72.4%, 95% CI: 67.4%-77.0%, pxerostomia were more likely to have SS than Sicca/ISS (OR=4.98, 95% CI: 3.78-6.56). The ability of xerostomia to screen for SS among those with salivary gland dysfunction was higher than screening for Sicca/ISS. Screening diagnostics of xerostomia were of greater utility compared to hyposalivation. After adjusting for confounding in multivariable modeling, SS participants with xerostomia were more likely to be White (Black/African Americans (OR: 0.40, 95% CI: 0.23-0.68, p-value=0.001) and Asians (OR: 0.49, 95% CI: 0.25-0.96, p-value=0.038) were less likely to have xerostomia compared to Whites), have dry eye symptoms for >3months (OR: 5.80, 95% CI: 3.62-9.28, p-value 2 (OR: 1.92, 95% CI: 1.20-3.09, p-value=0.007), and salivary gland swelling (OR: 49

  16. Radiation induced degradation of dyes-An overview

    International Nuclear Information System (INIS)

    Rauf, M.A.; Ashraf, S. Salman

    2009-01-01

    Synthetic dyes are a major part of our life. Products ranging from clothes to leather accessories to furniture all depend on extensive use of organic dyes. An unfortunate side effect of extensive use of these chemicals is that huge amounts of these potentially carcinogenic compounds enter our water supplies. Various advanced oxidation processes (AOPs) including the use of high-energy radiation have been developed to degrade these compounds. In this review, dye decoloration and degradation as a result of its exposure to high energy radiation such as gamma radiation and pulsed electron beam are discussed in detail. The role of various transient species such as ·H, ·OH and e aq - are taken into account as reported by various researchers. Literature citations in this area show that e aq - is very effective in decolorization but is less active in the further degradation of the products formed. The degradation of the dyes is initiated exclusively by ·OH attack on electron-rich sites of the dye molecules. Additionally, various parameters that affect the efficiency of radiation induced degradation of dyes, such as effect of radiation dose, oxygen, pH, hydrogen peroxide, added ions and dye classes are also reviewed and summarized. Lastly, pilot plant application of radiation for wastewater treatment is briefly discussed.

  17. Optical remote diagnostics of atmospheric propagating beams of ionizing radiation

    Science.gov (United States)

    Karl JR., Robert R.

    1990-03-06

    Data is obtained for use in diagnosing the characteristics of a beam of ionizing radiation, such as charged particle beams, neutral particle beams, and gamma ray beams. In one embodiment the beam is emitted through the atmosphere and produces nitrogen fluorescence during passage through air. The nitrogen fluorescence is detected along the beam path to provide an intensity from which various beam characteristics can be calculated from known tabulations. Optical detecting equipment is preferably located orthogonal to the beam path at a distance effective to include the entire beam path in the equipment field of view.

  18. Optical breakdown of helium in Bessel laser radiation beams

    International Nuclear Information System (INIS)

    Andreev, N E; Pleshanov, I V; Margolin, L Ya; Pyatnitskii, Lev N

    1998-01-01

    Numerical simulation is used to investigate the dynamics of formation of a helium plasma in Bessel beams, shaped by an axicon and a phase converter from a laser radiation pulse with Gaussian temporal and radial intensity profiles. The beam intensities at the breakdown threshold are determined as a function of the pulse duration for various radial field distributions in a beam characterised by Bessel functions of order m (m = 0 - 5). It is shown that in the investigated range of parameters the threshold intensity is independent of m. The temporal and spatial evolution of the resultant plasma, and the dependence of the plasma characteristics on the pulse parameters are considered. Conditions are found for the formation of tubular plasma channels in beams of orders m≥1. The adopted model of the optical breakdown of helium is shown to be satisfactory because of a good agreement between the results of calculations of the moment of breakdown in a zeroth-order Bessel beam and experimental results. (interaction of laser radiation with matter. laser plasma)

  19. Calibration methodology for instruments utilized in X radiation beams, diagnostic level

    International Nuclear Information System (INIS)

    Penha, M. da; Potiens, A.; Caldas, L.V.E.

    2004-01-01

    Methodologies for the calibration of diagnostic radiology instruments were established at the Calibration Laboratory of IPEN. The methods may be used in the calibration procedures of survey meters used in radiation protection measurements (scattered radiation), instruments used in direct beams (attenuated and non attenuated beams) and quality control instruments. The established qualities are recommended by the international standards IEC 1267 and ISO 4037-3. Two ionization chambers were used as reference systems, one with a volume of 30 cm 3 for radiation protection measurements, and the other with a volume of 1 cm 3 for direct beam measurements. Both are traceable to the German Primary Laboratory of Physikalisch-Technische Bundesanstalt (PTB). In the case of calibration of quality control instruments, a non-invasive method using the measurement of the spectrum endpoint was established with a portable gamma and X-ray Intertechnique spectrometer system. The methods were applied to survey meters (radiation protection measurements), ionization chambers (direct beam measurements) and k Vp meters (invasive and non-invasive instruments). (Author)

  20. Calibration methodology for instruments utilized in X radiation beams, diagnostic level

    Energy Technology Data Exchange (ETDEWEB)

    Penha, M. da; Potiens, A.; Caldas, L.V.E. [Instituto de Pesquisas Energeticas e Nucleares, Comissao Nacional de Energia Nuclear, Sao Paulo (Brazil)]. E-mail: mppalbu@ipen.br

    2004-07-01

    Methodologies for the calibration of diagnostic radiology instruments were established at the Calibration Laboratory of IPEN. The methods may be used in the calibration procedures of survey meters used in radiation protection measurements (scattered radiation), instruments used in direct beams (attenuated and non attenuated beams) and quality control instruments. The established qualities are recommended by the international standards IEC 1267 and ISO 4037-3. Two ionization chambers were used as reference systems, one with a volume of 30 cm{sup 3} for radiation protection measurements, and the other with a volume of 1 cm{sup 3} for direct beam measurements. Both are traceable to the German Primary Laboratory of Physikalisch-Technische Bundesanstalt (PTB). In the case of calibration of quality control instruments, a non-invasive method using the measurement of the spectrum endpoint was established with a portable gamma and X-ray Intertechnique spectrometer system. The methods were applied to survey meters (radiation protection measurements), ionization chambers (direct beam measurements) and k Vp meters (invasive and non-invasive instruments). (Author)

  1. The Theory of Coherent Radiation by Intense Electron Beams

    CERN Document Server

    Buts, Vyacheslav A; Kurilko, V.I

    2006-01-01

    Spurred by the development of high-current, high-energy relativistic electron beams this books delves into the foundations of a device and geometry independent theoretical treatment of a large collection of interacting and radiating electron bunches. Part I deals with the basics of the radiation emission of a single charged particle, paying particular attention to the effect of radiation reaction and dwelling on the corresponding well-known paradoxes. Part II investigates the collective behaviour of a high-density electron bunch where both discrete and continous beam modelling is explored. Part III treats the application to modern systems while still keeping the treatment as general as possible. This book will be mandatory reading for anyone working on the foundations of modern devices such as free electron lasers, plasma accelerators, synchroton sources and other modern sources of bright, coherent radiation with high spectral density.

  2. Induced radioactivity of materials by stray radiation fields at an electron accelerator

    CERN Document Server

    Rokni, S H; Gwise, T; Liu, J C; Roesler, S

    2002-01-01

    Samples of soil, water, aluminum, copper and iron were irradiated in the stray radiation field generated by the interaction of a 28.5 GeV electron beam in a copper-dump in the Beam Dump East facility at the Stanford Linear Accelerator Center. The specific activity induced in the samples was measured by gamma spectroscopy and other techniques. In addition, the isotope production in the samples was calculated with detailed Monte Carlo simulations using the FLUKA code. The calculated activities are compared to the experimental values and differences are discussed.

  3. Occurrence and impact of xerostomia among dentate adult New Zealanders: findings from a national survey.

    Science.gov (United States)

    Benn, A M L; Broadbent, J M; Thomson, W M

    2015-09-01

    We investigated the prevalence, associations and impact of xerostomia in a nationally representative sample of dentate adult community-dwelling New Zealanders aged 18 years and over. The data were collected from a representative sample of 2209 adults, as part of the 2009 New Zealand Oral Health Survey (NZOHS). Data were collected using face-to-face interviews, dental examinations and the short-form Oral Health Impact Profile (OHIP-14). Data analysis used appropriate weighting for all procedures to account for the complex survey design. The overall prevalence estimate for xerostomia was 13.1% (95% CI 11.7, 14.7), and it was more common among females. Those in the 75+  and 25-34 age groups were more likely (odds ratios of 6.5 and 4.0, respectively) to have xerostomia. After controlling for sociodemographic characteristics and clinical oral disease, the mean OHIP-14 score among xerostomics was 50% higher than among those who did not have the condition. These data indicate that xerostomia is a common condition which can affect quality of life among people of all ages. © 2015 Australian Dental Association.

  4. A new non intercepting beam size diagnostics using diffraction radiation from a Slit

    International Nuclear Information System (INIS)

    Castellano, M.

    1996-09-01

    A new non interpreting beam size diagnostic for high charge electron beams is presented. This diagnostics is based on the analysis of the angular distribution of the 'diffracted' transition radiation emitted by the beam when crossing a slit cut in metallic foil. It allows a resolution better then the radiation transverse formation zone. Numerical results based on the parameters of the TTF FEL beam are given as example

  5. Seeing the invisible: direct visualization of therapeutic radiation beams using air scintillation.

    Science.gov (United States)

    Fahimian, Benjamin; Ceballos, Andrew; Türkcan, Silvan; Kapp, Daniel S; Pratx, Guillem

    2014-01-01

    To assess whether air scintillation produced during standard radiation treatments can be visualized and used to monitor a beam in a nonperturbing manner. Air scintillation is caused by the excitation of nitrogen gas by ionizing radiation. This weak emission occurs predominantly in the 300-430 nm range. An electron-multiplication charge-coupled device camera, outfitted with an f/0.95 lens, was used to capture air scintillation produced by kilovoltage photon beams and megavoltage electron beams used in radiation therapy. The treatment rooms were prepared to block background light and a short-pass filter was utilized to block light above 440 nm. Air scintillation from an orthovoltage unit (50 kVp, 30 mA) was visualized with a relatively short exposure time (10 s) and showed an inverse falloff (r(2) = 0.89). Electron beams were also imaged. For a fixed exposure time (100 s), air scintillation was proportional to dose rate (r(2) = 0.9998). As energy increased, the divergence of the electron beam decreased and the penumbra improved. By irradiating a transparent phantom, the authors also showed that Cherenkov luminescence did not interfere with the detection of air scintillation. In a final illustration of the capabilities of this new technique, the authors visualized air scintillation produced during a total skin irradiation treatment. Air scintillation can be measured to monitor a radiation beam in an inexpensive and nonperturbing manner. This physical phenomenon could be useful for dosimetry of therapeutic radiation beams or for online detection of gross errors during fractionated treatments.

  6. Seeing the invisible: Direct visualization of therapeutic radiation beams using air scintillation

    Energy Technology Data Exchange (ETDEWEB)

    Fahimian, Benjamin; Türkcan, Silvan; Kapp, Daniel S.; Pratx, Guillem, E-mail: pratx@stanford.edu [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California 94305 (United States); Ceballos, Andrew [Department of Electrical Engineering, Stanford University, Stanford, California 94305 (United States)

    2014-01-15

    Purpose: To assess whether air scintillation produced during standard radiation treatments can be visualized and used to monitor a beam in a nonperturbing manner. Methods: Air scintillation is caused by the excitation of nitrogen gas by ionizing radiation. This weak emission occurs predominantly in the 300–430 nm range. An electron-multiplication charge-coupled device camera, outfitted with an f/0.95 lens, was used to capture air scintillation produced by kilovoltage photon beams and megavoltage electron beams used in radiation therapy. The treatment rooms were prepared to block background light and a short-pass filter was utilized to block light above 440 nm. Results: Air scintillation from an orthovoltage unit (50 kVp, 30 mA) was visualized with a relatively short exposure time (10 s) and showed an inverse falloff (r{sup 2} = 0.89). Electron beams were also imaged. For a fixed exposure time (100 s), air scintillation was proportional to dose rate (r{sup 2} = 0.9998). As energy increased, the divergence of the electron beam decreased and the penumbra improved. By irradiating a transparent phantom, the authors also showed that Cherenkov luminescence did not interfere with the detection of air scintillation. In a final illustration of the capabilities of this new technique, the authors visualized air scintillation produced during a total skin irradiation treatment. Conclusions: Air scintillation can be measured to monitor a radiation beam in an inexpensive and nonperturbing manner. This physical phenomenon could be useful for dosimetry of therapeutic radiation beams or for online detection of gross errors during fractionated treatments.

  7. Impact of xerostomia on dysphagia after chemotherapy-intensity-modulated radiotherapy for oropharyngeal cancer: Prospective longitudinal study.

    Science.gov (United States)

    Vainshtein, Jeffrey M; Samuels, Stuart; Tao, Yebin; Lyden, Teresa; Haxer, Marc; Spector, Matthew; Schipper, Matthew; Eisbruch, Avraham

    2016-04-01

    The purpose of this study was to assess how xerostomia affects dysphagia. Prospective longitudinal studies of 93 patients with oropharyngeal cancer treated with definitive chemotherapy-intensity-modulated radiotherapy (IMRT). Observer-rated dysphagia (ORD), patient-reported dysphagia (PRD), and patient-reported xerostomia (PRX) assessment of the swallowing mechanics by videofluoroscopy (videofluoroscopy score), and salivary flow rates, were prospectively assessed from pretherapy through 2 years. ORD grades ≥2 were rare and therefore not modeled. Of patients with no/mild videofluoroscopy abnormalities, a substantial proportion had PRD that peaked 3 months posttherapy and subsequently improved. Through 2 years, highly significant correlations were observed between PRX and PRD scores for all patients, including those with no/mild videofluoroscopy abnormalities. Both PRX and videofluoroscopy scores were highly significantly associated with PRD. On multivariate analysis, PRX score was a stronger predictor of PRD than the videofluoroscopy score. Xerostomia contributes significantly to PRD. Efforts to further decrease xerostomia, in addition to sparing parotid glands, may translate into improvements in PRD. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1605-E1612, 2016. © 2015 Wiley Periodicals, Inc.

  8. Electron-beam-induced structure transformation of the quasicrystalline phases of the Al 62Cu 20Co 15Si 3 alloy

    Science.gov (United States)

    Reyes-Gasga, J.; R. Garcia, G.; Jose-Yacaman, M.

    1995-02-01

    Some details on the phase transformation experienced by the quasicrystalline phases of the Al 62Cu 20Co 15Si 3 alloy under a 400 kV electron beam are given. The transition is observed in situ with a high resolution electron microscope and recorded on video tape. The results show that the electron beam radiation produces a sequence of changes similar to the ones observed in an ion-beam-induced amorphization process. Considering electron radiation damage analysis, the results agree well with the "flip-flop" model [Coddens, Bellisent, Calvayrac and Ambroise (1991) Europhys. Lett.16, 271] where the transition from a quasicrystalline phase to a crystalline phase is produced by atomic displacements but not in a cascade way.

  9. Dose-response relationship for chromosomal aberrations induced in human lymphocytes by 18 MeV electron beam irradiation

    International Nuclear Information System (INIS)

    Lashin, E.A.; Elaasar, E.M.; Moustafa, H.F.; Bakir, Y.Y.; Al Zenki, S.D.

    1990-01-01

    Dose response curves for lymphocyte chromosome aberration frequencies using X- and gamma radiation became an important and reliable indicator as biological dosimeter especially in radiation accidents and occupational over exposures. Nowadays electron beam therapy is frequently used for their advantages in cases of tumours under or near to the body surface. Dose-response curves for these electron beams are rarely published. Human peripheral blood lymphocytes were in vitro irradiated with various low and high doses (0.1 Gy to 4.9 Gy) of 18 MeV electron beams to utilize such a dose-response curve using chromosomal aberration frequencies as a biological indicator. Then we compared the biological curve with physically obtained curves normally used in planning for radiotherapy treatment. It is interesting to find a significant difference between both of them. The biological curve is generally higher in value and the aberrations induced by 93% of a dose is significantly higher and deeper in site than those aberrations induced by the 100% dose calculated physically. If the above observation is confirmed by detailed studies, it would be of importance to the radiotherapist to plan for isodose curves according to biological determinations. (author)

  10. Schemes of Superradiant Emission from Electron Beams and "Spin-Flip Emission of Radiation"

    CERN Document Server

    Gover, A

    2005-01-01

    A unified analysis for Superradiant emission from bunched electron beams in various kinds of radiation scheme is presented. Radiation schemes that can be described by the formulation include Pre-bunched FEL (PB-FEL), Coherent Synchrotron Radiation (CSR), Smith-Purcell Radiation, Cerenkov-Radiation, Transition-Radiation and more. The theory is based on mode excitation formulation - either discrete or continuous (the latter - in open structures). The discrete mode formulation permits simple evaluation of the spatially coherent power and spectral power of the source. These figures of merit of the radiation source are useful for characterizing and comparing the performance of different radiation schemes. When the bunched electron beam emits superradiantly, these parameters scale like the square of the number of electrons, orders of magnitude more than spontaneous emission. The formulation applies to emission from single electron bunches, periodically bunched beams, or emission from a finite number of bunches in a...

  11. Oral care of the cancer patient receiving radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Holtzhausen, T [Medical Univ. of Southern Africa, Pretoria (South Africa). Dept. of Community Dentistry

    1982-07-01

    Radiation therapy is frequently being used for the patient with oral cancer. The survival rate is increasing, due to more effective treatment technique. The question of whether any teeth should be extracted, the mode of therapy and the side effects of radiation like Xerostomia, caries, stomatitis, trismus and osteo-radionecrosis and also post radiation care are discussed.

  12. Proton-beam radiation therapy dosimetry standardization

    International Nuclear Information System (INIS)

    Gall, K.P.

    1995-01-01

    Beams of protons have been used for radiation therapy applications for over 40 years. In the last decade the number of facilities treating patients and the total number of patients being treated has begun go grow rapidly. Due to the limited and experimental nature of the early programs, dosimetry protocols tended to be locally defined. With the publication of the AAPM Task Group 20 report open-quotes Protocol for Dosimetry of Heavy Charged Particlesclose quotes and the open-quotes European Code of Practice for Proton-Beam Dosimetryclose quotes the practice of determining dose in proton-beam therapy was somewhat unified. The ICRU has also recently commissioned a report on recommendations for proton-beam dosimetry. There have been three main methods of determining proton dose; the Faraday cup technique, the ionization chamber technique, and the calorimeter technique. For practical reasons the ionization chamber technique has become the most widely used. However, due to large errors in basic parameters (e.g., W-value) is also has a large uncertainty for absolute dose. It has been proposed that the development of water calorimeter absorbed dose standards would reduce the uncertainty in absolute proton dose as well as the relative dose between megavoltage X-ray beams and proton beams. The advantages and disadvantages are discussed

  13. Theoretical and experimental study of an energy-reinforced braking radiation photon beam

    International Nuclear Information System (INIS)

    Bertin, Pierre-Yves

    1966-01-01

    This research thesis reports the theoretical study of a photon beam raised towards high energies, its experimental implementation, the definition of a gamma spectrometry method which aimed at checking various hypotheses used in the beam theoretical study. After a presentation of the theory of phenomena of electron braking radiation, of materialisation of photons into positon-negaton pair, and of issues related to multiple Coulomb diffusion, the author reports the study of the different solutions which allow a photon beam to be obtained. A braking radiation of mono-kinetic electron has been used. This braking radiation is reinforced by absorption of low energy protons in a column of lithium hydride. The author describes how the beam is built up, and the experimental approach. He describes how raw data are processed to get rid of the influence of the multiple Coulomb diffusion and of the braking radiation. Experimental results are compared with those obtained by convolution of photon spectra and differential cross section

  14. An analysis of whistler mode radiation from a 100 mA electron beam

    International Nuclear Information System (INIS)

    Goerke, R.T.; Kellogg, P.J.; Monson, S.J.

    1990-01-01

    Observations of whistler mode radiation generated by 2-, 4-, and 8-keV electron beams with a current of 100 mA, are analyzed. The electron accelerator was carried to ionospheric heights by a Nike Black Brant V rocket (National Research Council of Canada NVB-06). The instability causing the whistler mode radiation is investigated. Spectral measurements (0.1-13.0 MHz), from a sweeping receiver located on the ejected forward payload, are used to determine the nature of the instability. The sweeping receiver was connected alternatively to an electric or a magnetic dipole antenna. Most of the whistler mode radiation detected was consistent with Cerenkov radiation. The radiation fields observed were too large (cB ∼ 0.1 μV/m Hz 1/2 ) to be explained by incoherent processes. If electrostatic bunching in the beam at the plasma frequency is responsible for the whistler radiation, there would be a correlation between the plasma frequency radiation, and the whistler mode radiation for electron beams that are fired toward the detector. The observed correlation is minimal. Hence no evidence was found to support the hypothesis that electrostatic bunching at the plasma frequency was responsible for the enhancement of the whistler mode radiation produced by the NVB-06 electron beam

  15. Salivary gland dysplasia in fgf10 heterozygous mice:A new mouse model of xerostomia

    OpenAIRE

    May, A. J.; Chatzeli, L.; Proctor, G. B.; Tucker, A. S.

    2015-01-01

    Xerostomia, or chronic dry mouth, is a common syndrome caused by a lack of saliva that can lead to severe eating difficulties, dental caries and oral candida infections. The prevalence of xerostomia increases with age and affects approximately 30% of people aged 65 or older. Given the large numbers of sufferers, and the potential increase in incidence given our aging population, it is important to understand the complex mechanisms that drive hyposalivation and the consequences for the dentiti...

  16. Study of radiation detectors response in standard X, gamma and beta radiation standard beams

    International Nuclear Information System (INIS)

    Nonato, Fernanda Beatrice Conceicao

    2010-01-01

    The response of 76 Geiger-Mueller detectors, 4 semiconductor detectors and 34 ionization chambers were studied. Many of them were calibrated with gamma radiation beams ( 37 Cs and 60 Co), and some of them were tested in beta radiation ( 90 Sr+ 9' 0Y e 204 Tl) and X radiation (N-60, N-80, N-100, N-150) beams. For all three types of radiation, the calibration factors of the instruments were obtained, and the energy and angular dependences were studied. For beta and gamma radiation, the angular dependence was studied for incident radiation angles of 0 deg and +- 45 deg. The curves of the response of the instruments were obtained over an angle interval of 0 deg to +- 90 deg, for gamma, beta and X radiations. The calibration factors obtained for beta radiation were compared to those obtained for gamma radiation. For gamma radiation, 24 of the 66 tested Geiger-Mueller detectors presented results for the energy dependence according to international recommendation of ISO 4037-2 and 56 were in accordance with the Brazilian ABNT 10011 recommendation. The ionization chambers and semiconductors were in accordance to national and international recommendations. All instruments showed angular dependence less than 40%. For beta radiation, the instruments showed unsatisfactory results for the energy dependence and angular dependence. For X radiation, the ionization chambers presented results for energy dependence according to the national recommendation, and the angular dependence was less than 40%. (author)

  17. Radiation-Induced Leukemia at Doses Relevant to Radiation Therapy: Modeling Mechanisms and Estimating Risks

    Science.gov (United States)

    Shuryak, Igor; Sachs, Rainer K.; Hlatky, Lynn; Mark P. Little; Hahnfeldt, Philip; Brenner, David J.

    2006-01-01

    Because many cancer patients are diagnosed earlier and live longer than in the past, second cancers induced by radiation therapy have become a clinically significant issue. An earlier biologically based model that was designed to estimate risks of high-dose radiation induced solid cancers included initiation of stem cells to a premalignant state, inactivation of stem cells at high radiation doses, and proliferation of stem cells during cellular repopulation after inactivation. This earlier model predicted the risks of solid tumors induced by radiation therapy but overestimated the corresponding leukemia risks. Methods: To extend the model to radiation-induced leukemias, we analyzed in addition to cellular initiation, inactivation, and proliferation a repopulation mechanism specific to the hematopoietic system: long-range migration through the blood stream of hematopoietic stem cells (HSCs) from distant locations. Parameters for the model were derived from HSC biologic data in the literature and from leukemia risks among atomic bomb survivors v^ ho were subjected to much lower radiation doses. Results: Proliferating HSCs that migrate from sites distant from the high-dose region include few preleukemic HSCs, thus decreasing the high-dose leukemia risk. The extended model for leukemia provides risk estimates that are consistent with epidemiologic data for leukemia risk associated with radiation therapy over a wide dose range. For example, when applied to an earlier case-control study of 110000 women undergoing radiotherapy for uterine cancer, the model predicted an excess relative risk (ERR) of 1.9 for leukemia among women who received a large inhomogeneous fractionated external beam dose to the bone marrow (mean = 14.9 Gy), consistent with the measured ERR (2.0, 95% confidence interval [CI] = 0.2 to 6.4; from 3.6 cases expected and 11 cases observed). As a corresponding example for brachytherapy, the predicted ERR of 0.80 among women who received an inhomogeneous low

  18. Verification of Radiation Isocenter on Linac Beam 6 MV using Computed Radiography

    Science.gov (United States)

    Irsal, Muhammad; Hidayanto, Eko; Sutanto, Heri

    2017-06-01

    Radiation isocenter is more important part of quality assurance for the linear accelerator (Linac) due to radiation isocenter is a main location in irradiation radiotherapy, isocenter can shift when the gantry and collimator rotation. In general, the radiation isocenter verification using a special film. This research was conducted radiation isocenter verification using computed radiography with digital image processing techniques. Image acquisition was done using the modalities of Linac 6 MV with star shot method is star-shaped beam due to rotation of the collimator, gantry and couch. Then do the delineation on each beam to determine the centroid and beam diameter. By the results of verification of radiation isocenter performed on collimator and the couch, it shows that the size diameter for rotational collimator is 0.632 mm and 0.458 mm for the couch. Based on AAPM report 40 about the size of the Linac radiation isocenter diameter used in this study is still in good condition and worth to be operated because the value of the radiation isocenter diameter is below 2 mm.

  19. Verification of Radiation Isocenter on Linac Beam 6 MV using Computed Radiography

    International Nuclear Information System (INIS)

    Irsal, Muhammad; Hidayanto, Eko; Sutanto, Heri

    2017-01-01

    Radiation isocenter is more important part of quality assurance for the linear accelerator (Linac) due to radiation isocenter is a main location in irradiation radiotherapy, isocenter can shift when the gantry and collimator rotation. In general, the radiation isocenter verification using a special film. This research was conducted radiation isocenter verification using computed radiography with digital image processing techniques. Image acquisition was done using the modalities of Linac 6 MV with star shot method is star-shaped beam due to rotation of the collimator, gantry and couch. Then do the delineation on each beam to determine the centroid and beam diameter. By the results of verification of radiation isocenter performed on collimator and the couch, it shows that the size diameter for rotational collimator is 0.632 mm and 0.458 mm for the couch. Based on AAPM report 40 about the size of the Linac radiation isocenter diameter used in this study is still in good condition and worth to be operated because the value of the radiation isocenter diameter is below 2 mm. (paper)

  20. Radiation-induced erectile dysfunction: Recent advances and future directions

    Directory of Open Access Journals (Sweden)

    Javed Mahmood, PhD

    2016-07-01

    Full Text Available Prostate cancer is one of the most prevalent cancers and the second leading cause of cancer-related deaths in men in the United States. A large number of patients undergo radiation therapy (RT as a standard care of treatment; however, RT causes erectile dysfunction (radiation-induced erectile dysfunction; RiED because of late side effects after RT that significantly affects quality of life of prostate cancer patients. Within 5 years of RT, approximately 50% of patients could develop RiED. Based on the past and current research findings and number of publications from our group, the precise mechanism of RiED is under exploration in detail. Recent investigations have shown prostate RT induces significant morphologic arterial damage with aberrant alterations in internal pudendal arterial tone. Prostatic RT also reduces motor function in the cavernous nerve which may attribute to axonal degeneration may contributing to RiED. Furthermore, the advances in radiogenomics such as radiation induced somatic mutation identification, copy number variation and genome-wide association studies has significantly facilitated identification of biomarkers that could be used to monitoring radiation-induced late toxicity and damage to the nerves; thus, genomic- and proteomic-based biomarkers could greatly improve treatment and minimize arterial tissue and nerve damage. Further, advanced technologies such as proton beam therapy that precisely target tumor and significantly reduce off-target damage to vital organs and healthy tissues. In this review, we summarize recent advances in RiED research and novel treatment modalities for RiED. We also discuss the possible molecular mechanism involved in the development of RiED in prostate cancer patients. Further, we discuss various readily available methods as well as novel strategies such as stem cell therapies, shockwave therapy, nerve grafting with tissue engineering, and nutritional supplementations might be used to

  1. In situ beam analysis of radiation damage kinetics in MgTiO3 single crystals at 170-470 K

    International Nuclear Information System (INIS)

    Yu, Ning; Mitchell, J.N.; Sickafus, K.E.; Nastasi, M.

    1995-01-01

    Radiation damage kinetics in synthetic MgTiO 3 (geikielite) single crystals have been studied using the in situ ion beam facility at Los Alamos National Laboratory. The geikielite samples were irradiated at temperatures of 170, 300, and 470 K with 400 keV xenon ions and the radiation damage was sequentially measured with Rutherford backscattering using a 2 MeV He ion beam along a channeling direction. Threshold doses of I and 5x l0 15 Xe/cm 2 were determined for the crystalline-to-amorphous transformation induced by Xe ion irradiation at 170 and 300 K, respectively. However, geikielite retained its crystallinity up to a dose of 2.5xl0 16 Xe/cm 2 at the irradiation temperature of 470 K. This study has shown that MgTiO 3 , which has a corundum derivative structure, is another radiation resistant material that has the potential for use in radiation environments

  2. Magnetic resonance sialography for investigating major salivary gland duct system after intensity-modulated radiotherapy of nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Ou Dan; He Xiayun; Zhang Yunyan

    2013-01-01

    We investigated the value of magnetic resonance sialography for evaluating xerostomia induced by intensity-modulated radiotherapy for nasopharyngeal carcinoma. Fourteen patients with nasopharyngeal carcinoma were treated with intensity-modulated radiotherapy. Salivary function was assessed by magnetic resonance sialography and subjective evaluation criteria pre-treatment, 1 week and 1 year post-radiotherapy. A magnetic resonance sialography categorical scoring system was used to compare the visibility of salivary ducts. The average mean dose was 38.93 Gy to the parotid glands and 59.34 Gy to the submandibular glands. Before radiotherapy, the visibility scores of both the parotid and submandibular ducts increased after secretion stimulation. The scores decreased and the response to stimulation was attenuated 1 week post-radiotherapy. For most of the parotid ducts, the visibility score improved at 1 year post-radiotherapy both at rest and under stimulation, but not for the submandibular ducts. With a median follow-up of 12.3 months, 8/12 patients had grade 1 xerostomia and 4/12 had grade 2 xerostomia. Magnetic resonance sialography allows non-invasive evaluation of radiation-induced ductal changes in the major salivary glands and enables reliable prediction of radiation-induced xerostomia. (author)

  3. Prevalence of Candida spp., xerostomia, and hyposalivation in oral lichen planus--a controlled study.

    Science.gov (United States)

    Artico, G; Freitas, R S; Santos Filho, A M; Benard, G; Romiti, R; Migliari, D A

    2014-04-01

    To determine the frequency of Candida spp., xerostomia, and salivary flow rate (SFR) in three different groups: patients with OLP (OLP group), patients with oral mucosal lesions other than OLP (non-OLP group), and subjects without oral mucosal lesions (control group). Xerostomia as well as SFR was investigated in the three groups. Samples for isolation of Candida spp. were collected from OLP lesions (38 patients), non-OLP lesions (28 patients), and healthy subjects (32 subjects). There was no statistically significant difference regarding the frequency of xerostomia and hyposalivation among the three groups (P > 0.05). A higher prevalence for colonization by Candida spp. was found in the healthy subject as compared to that of patients with OLP (P = 0.03) and non-OLP (P = 0.02) groups. Low SFR was not a factor for colonization by Candida spp. Xerostomia and hyposalivation occur with similar frequency in subjects with and without oral lesions; also, the presence of oral lesions does not increase the susceptibility to colonization by Candida spp. It seems that any study implicating Candida spp. in the malignant transformation of oral lesions should be carried out mostly on a biochemical basis, that is, by testing the capability of Candida spp. to produce carcinogenic enzyme. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. Thermoacoustic emission induced by deeply-penetrating radiation and its application to biomedical imaging

    International Nuclear Information System (INIS)

    Liew, Soo Chin.

    1989-01-01

    Thermoacoustic emissions induced by 2450 MHz microwave pulses in water, tissue-simulating phantoms and dog kidneys have been detected. The analytic signal magnitude has been employed in generating A-mode images with excellent depth resolution. Thermoacoustic emissions have also been detected from the dose-gradient at the beam edges of a 4 MeV x-ray beam in water. These results establish the feasibility of employing thermoacoustic signals in generating diagnostic images, and in locating x-ray beam edges during radiation therapy. A theoretical model for thermoacoustic imaging using a directional transducer has been developed, which may be used in the design of future thermoacoustic imaging system, and in facilitating comparisons with other types of imaging systems. A method of characterizing biological tissues has been proposed, which relates the power spectrum of the detected thermoacoustic signals to the autocorrelation function of the thermoacoustic source distribution in the tissues. The temperature dependence of acoustic signals induced by microwave pulses in water has been investigated. A microwave-induced thermoacoustic source capable of launching large aperture, unipolar ultrasonic plane wave pulses in water has been constructed

  5. Radiation induced time dependent attenuation in a fiber

    International Nuclear Information System (INIS)

    Kelly, R.E.; Lyons, P.B.; Looney, L.D.

    1985-01-01

    Characteristics describing the time dependent attenuation coefficient of an optical fiber during and following a very short and intense radiation pulse are analyzed. This problem is important for transmission applications when the fiber is subjected to gamma, electron, or neutron beams. Besides time, the attenuation coefficient is a function of temperature, dose rate, dose, nature of the radiation (n, e, γ), fiber composition and purity, pre-existing solid state defects, and wavelength of the transmitted signal. The peak attenuation for a given fiber is mainly determined by the dose rate and pulse length, but temperature and strain (or athermal) annealing also contribute to a partial recovery during the pulse duration. The peak attenuation per unit dose appears to be smaller at high doses, perhaps caused by particle track overlap, which produces a saturation effect. After pulse termination, the attenuation coefficient tends to recover towards its pre-radiation value at different rates, depending upon the factors mentioned above. In particular, ionized electrons relax back to the positive lattice ions at a rate which depends upon initial separation distance and temperature. The initial separation distance is a function of beam energy. Some electrons will encounter a trap in the lattice and may recombine by quantum mechanical tunneling or be removed by photons (hence, absorption). Besides ionization, radiation may induce lattice displacements which in turn produce additional absorption centers. The displacement contribution has a different time constant than that associated with ionization. These topics, as they influence fiber characteristics, are discussed, along with supporting experimental data

  6. Two-Year and Lifetime Cost-Effectiveness of Intensity Modulated Radiation Therapy Versus 3-Dimensional Conformal Radiation Therapy for Head-and-Neck Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Kohler, Racquel E. [Department of Health Policy and Management, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina (United States); Sheets, Nathan C. [Department of Radiation Oncology, University of North Carolina Hospitals, Chapel Hill, North Carolina (United States); Wheeler, Stephanie B. [Department of Health Policy and Management, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina (United States); Nutting, Chris [Royal Marsden Hospital, London, United Kindom (United Kingdom); Hall, Emma [Clinical Trials and Statistics Unit, Division of Clinical Studies, Institute of Cancer Research, London (United Kingdom); Chera, Bhishamjit S., E-mail: bchera@med.unc.edu [Department of Radiation Oncology, University of North Carolina Hospitals, Chapel Hill, North Carolina (United States)

    2013-11-15

    Purpose: To assess the cost-effectiveness of intensity modulated radiation therapy (IMRT) versus 3-dimensional conformal radiation therapy (3D-CRT) in the treatment of head-and neck-cancer (HNC). Methods and Materials: We used a Markov model to simulate radiation therapy-induced xerostomia and dysphagia in a hypothetical cohort of 65-year-old HNC patients. Model input parameters were derived from PARSPORT (CRUK/03/005) patient-level trial data and quality-of-life and Medicare cost data from published literature. We calculated average incremental cost-effectiveness ratios (ICERs) from the US health care perspective as cost per quality-adjusted life-year (QALY) gained and compared our ICERs with current cost-effectiveness standards whereby treatment comparators less than $50,000 per QALY gained are considered cost-effective. Results: In the first 2 years after initial treatment, IMRT is not cost-effective compared with 3D-CRT, given an average ICER of $101,100 per QALY gained. However, over 15 years (remaining lifetime on the basis of average life expectancy of a 65-year-old), IMRT is more cost-effective at $34,523 per QALY gained. Conclusion: Although HNC patients receiving IMRT will likely experience reduced xerostomia and dysphagia symptoms, the small quality-of-life benefit associated with IMRT is not cost-effective in the short term but may be cost-effective over a patient's lifetime, assuming benefits persist over time and patients are healthy and likely to live for a sustained period. Additional data quantifying the long-term benefits of IMRT, however, are needed.

  7. Cryopump behavior in the presence of beam or nuclear radiation

    International Nuclear Information System (INIS)

    Law, P.K.

    1977-12-01

    Cryocondensation pumping has been proposed to be the method of gas removal for neutral-beam refueled fusion reactors. A cryocondensation pumping unit has been constructed to test design concepts and compatibility with conditions under actual beam operation and nuclear radiation environment. Various operating parameters for this test pumping unit have been measured, including pumping speeds for various gases and beam desorption effects. An experiment has been planned at the Berkeley Research Reactor to measure the desorption effects of high energy neutrons and gamma radiation. A foil activation method has been devised to accurately assess the energy spectrum of this neutron source, which is expected to be comparable to that of the Tokamak Fusion Test Reactor

  8. Sedative load and salivary secretion and xerostomia in community-dwelling older people.

    Science.gov (United States)

    Tiisanoja, Antti; Syrjälä, Anna-Maija; Komulainen, Kaija; Hartikainen, Sirpa; Taipale, Heidi; Knuuttila, Matti; Ylöstalo, Pekka

    2016-06-01

    The aim was to investigate how sedative load and the total number of drugs used are related to hyposalivation and xerostomia among 75-year-old or older dentate, non-smoking, community-dwelling people. The study population consisted of 152 older people from the Oral Health GeMS study. The data were collected by interviews and clinical examinations during 2004-2005. Sedative load, which measures the cumulative effect of taking multiple drugs with sedative properties, was calculated using the Sedative Load Model. The results showed that participants with a sedative load of either 1-2 or ≥3 had an increased likelihood of having low stimulated salivary flow (xerostomia (OR: 2.5, CI: 0.5-12) compared with participants without a sedative load. The results showed that the association between the total number of drugs and hyposalivation was weaker than the association between sedative load and hyposalivation. Sedative load is strongly related to hyposalivation and to a lesser extent with xerostomia. The adverse effects of drugs on saliva secretion are specifically related to drugs with sedative properties. © 2014 John Wiley & Sons A/S and The Gerodontology Association. Published by John Wiley & Sons Ltd.

  9. The technology and economics of treating waste water with electron beam radiation

    International Nuclear Information System (INIS)

    Cleland, M.R.

    1976-01-01

    The use of ionizing radiation from electron beam accelerators is considered in this paper for the disinfection of waste water. Combinations of radiation with oxygen, chlorine, heat and retention media are discussed as possible methods to reduce the dosage requirements and the treatment costs. The production of ozone by the irradiation of oxygen is also evaluated as an alternative method of using this form of energy. The capital and operating costs for large electron beam facilities are analyzed to show the favorable trends with rising power levels. Cost comparisons between conventional disinfection processes and two radiation processes are presented and discussed. The results of these cost analyses support the premise that electron beam radiation should be evaluated as a likely competitor to ozonation or carbon filtration for large sewage treatment plants. (author)

  10. The technology and economics of treating waste water with electron beam radiation

    International Nuclear Information System (INIS)

    Cleland, M.R.

    1976-01-01

    The use of ionizing radiation from electron beam accelerators is considered in this paper for the disinfection of waste water. Combinations of radiation with oxygen, chlorine, heat and retention media are discussed as possible methods to reduce the dosage requirements and the treatment costs. The production of ozone by the irradiation of oxygen is also evaluated as an alternative method of using this form of energy. The capital and operating costs for large electron beam facilities are analyzed to show the favorable trends with rising power levels. Cost comparisons between 'conventional' disinfection processes and two radiation processes are presented and discussed. The results of these cost analyses support the premise that electron beam radiation should be evaluated as a likely competitor to ozonation or carbon filtration for large sewage treatment plants. (orig.) [de

  11. Successful beam tests for ALICE Transition Radiation Detector

    CERN Multimedia

    2002-01-01

    Another round of beam tests of prototypes for the Transition Radiation Detector (TRD) for ALICE has been completed and there are already some good results. Mass production of the components of the detector will start early next year.   Top view of the setup for the Transition Radiation Detector prototype tests at CERN.On the left, can be seen the full-scale TRD prototype together with four smaller versions. These are busy days for the TRD (Transition Radiation Detector) team of ALICE. Twenty people - mainly from Germany, but also from Russia and Japan - were working hard during the beam tests this autumn at CERN to assess the performance of their detector prototypes. Analysis of the data shows that the TRD can achieve the desired physics goal even for the highest conceivable multiplicities in lead-lead collisions at the LHC. In its final configuration in the ALICE experiment, the TRD will greatly help in identifying high-momentum electrons, which are 'needles in a haystack' that consists mostly of...

  12. Development of NTCP models for head and neck cancer patients treated with three-dimensional conformal radiotherapy for xerostomia and sticky saliva: The role of dosimetric and clinical factors

    International Nuclear Information System (INIS)

    Beetz, Ivo; Schilstra, Cornelis; Burlage, Fred R.; Koken, Phil W.; Doornaert, Patricia; Bijl, Henk P.; Chouvalova, Olga; Leemans, C. René; Bock, Geertruida H. de; Christianen, Miranda E.M.C.; Laan, Bernard F.A.M. van der; Vissink, Arjan; Steenbakkers, Roel J.H.M.; Langendijk, Johannes A.

    2012-01-01

    Purpose: The purpose of this multicentre prospective study was to investigate the significance of the radiation dose in the major and minor salivary glands, and other pre-treatment and treatment factors, with regard to the development of patient-rated xerostomia and sticky saliva among head and neck cancer (HNC) patients treated with primary (chemo-) radiotherapy ((CH)RT). Methods and materials: The study population was composed of 167 consecutive HNC patients treated with three-dimensional conformal (3D-CRT) (CH) RT. The primary endpoint was moderate to severe xerostomia (XER6m) as assessed by the EORTC QLQ-H and N35 at 6 months after completing (CH)RT. The secondary endpoint was moderate to severe sticky saliva at 6 months (STIC6 m). All organs at risk (OARs) potentially involved in salivary function were delineated on planning-CT, including the parotid, submandibular and sublingual glands and the minor glands in the soft palate, cheeks and lips. Patients with moderate to severe xerostomia or sticky saliva at baseline were excluded. The optimum number of variables for a multivariate logistic regression model was determined using a bootstrapping method. Results: The multivariate analysis showed the mean parotid dose, age and baseline xerostomia (none versus a bit) to be the most important predictors for XER6m. The risk of developing xerostomia increased with age and was higher when minor baseline xerostomia was present in comparison with patients without any xerostomia complaints at baseline. Model performance was good with an area under the curve (AUC) of 0.82. For STIC6m, the mean submandibular dose, age, the mean sublingual dose and baseline sticky saliva (none versus a bit) were most predictive for sticky saliva. The risk of developing STIC6 m increased with age and was higher when minor baseline sticky saliva was present in comparison with patients without any sticky saliva complaints at baseline. Model performance was good with an AUC of 0.84. Conclusions

  13. Electron beam induced conductivity in 'PET' and 'FEP'

    International Nuclear Information System (INIS)

    Walzade, S.J.; Jog, J.P.; Dake, S.B.; Bhoraskar, S.V.

    1983-01-01

    Electron Beam Induced Conductivity (EBIC), classified into EBIC (bulk) and EBIC (surface) have been measured in PET and FEP respectively. The peculiar oscillatory nature of the induced gain versus beam energy variations is explained in terms of the spatial distributions of the trapping centres near the surface of the polymers. (author)

  14. Radiation optic neuropathy after external beam radiation therapy for acromegaly: report of two cases

    International Nuclear Information System (INIS)

    Bergh, Alfons C.M. van den; Hoving, Marjanke A.; Links, Thera P.; Dullaart, Robin P.F.; Ranchor, Adelita V.; Weeme, Cees A. ter; Canrinus, Alof A.; Szabo, Ben G.; Pott, Jan-Willem R.

    2003-01-01

    For diagnosing radiation optic neuropathy (RON) ophthalmological and imaging data were evaluated from 63 acromegalic patients, irradiated between 1967 and 1998. Two patients developed RON: one patient in one optic nerve 10 years and another patient in both optic nerves 5 months after radiation therapy. RON is a rare complication after external beam radiation therapy for acromegaly, which can occur after a considerable latency period

  15. Radiation-induced refraction artifacts in the optical CT readout of polymer gel dosimeters

    International Nuclear Information System (INIS)

    Campbell, Warren G.; Jirasek, Andrew; Wells, Derek M.

    2014-01-01

    Purpose: The objective of this work is to demonstrate imaging artifacts that can occur during the optical computed tomography (CT) scanning of polymer gel dosimeters due to radiation-induced refractive index (RI) changes in polyacrylamide gels. Methods: A 1 L cylindrical polyacrylamide gel dosimeter was irradiated with 3 × 3 cm 2 square beams of 6 MV photons. A prototype fan-beam optical CT scanner was used to image the dosimeter. Investigative optical CT scans were performed to examine two types of rayline bending: (i) bending within the plane of the fan-beam and (ii) bending out the plane of the fan-beam. To address structured errors, an iterative Savitzky–Golay (ISG) filtering routine was designed to filter 2D projections in sinogram space. For comparison, 2D projections were alternatively filtered using an adaptive-mean (AM) filter. Results: In-plane rayline bending was most notably observed in optical CT projections where rays of the fan-beam confronted a sustained dose gradient that was perpendicular to their trajectory but within the fan-beam plane. These errors caused distinct streaking artifacts in image reconstructions due to the refraction of higher intensity rays toward more opaque regions of the dosimeter. Out-of-plane rayline bending was observed in slices of the dosimeter that featured dose gradients perpendicular to the plane of the fan-beam. These errors caused widespread, severe overestimations of dose in image reconstructions due to the higher-than-actual opacity that is perceived by the scanner when light is bent off of the detector array. The ISG filtering routine outperformed AM filtering for both in-plane and out-of-plane rayline errors caused by radiation-induced RI changes. For in-plane rayline errors, streaks in an irradiated region (>7 Gy) were as high as 49% for unfiltered data, 14% for AM, and 6% for ISG. For out-of-plane rayline errors, overestimations of dose in a low-dose region (∼50 cGy) were as high as 13 Gy for unfiltered

  16. Stabilization of synchrotron radiation x-ray beam by MOSTAB

    CERN Document Server

    Kudo, T P; Tanida, H; Furukawa, Y; Hirono, T; Ishikawa, T; Nishino, Y

    2003-01-01

    Monochromator stabilization (MOSTAB) is a feedback control system to stabilize an x-ray beam of synchrotron radiation. It applies a feedback voltage to a piezo electric transducer attached to a double-crystal monochromator. We developed MOSTAB modules and examined their performances using SPring-8 beamlines. The x-ray beam position stabilization using MOSTAB was realized simultaneously with the x-ray beam intensity stabilization. As an example of its application, we performed EXAFS measurement with MOSTAB. (author)

  17. Radiation-related caries. Etiology and possible preventive strategies. What should the radiotherapist know?

    International Nuclear Information System (INIS)

    Schweyen, R.; Hey, J.; Fraenzel, W.; Vordermark, D.; Hildebrandt, G.; Kuhnt, T.

    2012-01-01

    After radiation treatment of head-and-neck cancer, the impairment of patient's quality of life still remains an issue. After completion of the treatment course, a substantial number of patients develop so-called radiation caries. In addition, almost 50% of all cases of infectious osteoradionecrosis (iORN) of the jaws are directly associated with radiation caries. This review addresses our current knowledge on the etiology and pathogenesis of radiation caries including possible preventive strategies. Materials and methods A PubMed search using the terms ''radiation caries'' (''radiation related caries'', ''radiation related damage to dentition'') and ''radiogenic caries'' (''postradiation caries'', ''dental complications and radiotherapy'') was performed. The analysis of its content focused on the etiology, the pathogenesis, and the available knowledge on prophylaxis as well as treatment of radiation caries. Results For this review, 60 publications were selected. As main causal factors for radiogenic caries, either indirect impairment, resulting from alterations in the oral environment (e.g., radiation-induced xerostomia) or direct radiation-induced damage in teeth hard tissues are discussed. Radiation caries remains a lifelong threat and, therefore, requires permanent prevention programs. Conclusion To enable optimal medical care of the patients during the time course of radiotherapy as well as afterwards, close interdisciplinary cooperation between radiotherapists, oral surgeons, otorhinolaryngologists, and dentists is absolutely essential. (orig.)

  18. Betatron radiation based diagnostics for plasma wakefield accelerated electron beams at the SPARC-LAB test facility

    Energy Technology Data Exchange (ETDEWEB)

    Shpakov, V.; Anania, M.P.; Biagioni, A.; Chiadroni, E. [INFN - LNF, via Enrico Fermi 40, 00044 Frascati (Italy); Cianchi, A. [INFN - LNF, via Enrico Fermi 40, 00044 Frascati (Italy); “Tor Vergata” University, via della Ricerca Scientifica 1, 00133 Rome (Italy); Curcio, A. [INFN - LNF, via Enrico Fermi 40, 00044 Frascati (Italy); Dabagov, S. [INFN - LNF, via Enrico Fermi 40, 00044 Frascati (Italy); P.N. Lebedev Physical Institute RAS, Leninskiy Prospekt 53, 119991 Moscow (Russian Federation); NRNU “MEPhI”, Kashirskoe highway 31, 115409 Moscow (Russian Federation); Ferrario, M.; Filippi, F. [INFN - LNF, via Enrico Fermi 40, 00044 Frascati (Italy); Marocchino, A. [Dipartimento SBAI Universitá di Roma ‘La Sapienza’, via Antonio Scarpa 14/16, 00161 Rome (Italy); Paroli, B. [INFN - MI, via Celoria 16, 20133 Milan (Italy); Pompili, R. [INFN - LNF, via Enrico Fermi 40, 00044 Frascati (Italy); Rossi, A.R. [INFN - MI, via Celoria 16, 20133 Milan (Italy); Zigler, A. [Racah Institute of Physics Hebrew University of Jerusalem (Israel)

    2016-09-01

    Recent progress with wake-field acceleration has shown a great potential in providing high gradient acceleration fields, while the quality of the beams remains relatively poor. Precise knowledge of the beam size at the exit from the plasma and matching conditions for the externally injected beams are the key for improvement of beam quality. Betatron radiation emitted by the beam during acceleration in the plasma is a powerful tool for the transverse beam size measurement, being also non-intercepting. In this work we report on the technical solutions chosen at SPARC-LAB for such diagnostics tool, along with expected parameters of betatron radiation. - Highlights: • The betatron radiation parameters in SPARC-LAB wakefiled experiments were studied. • The differences with betatron radiation in other wake-field experiments were highlighted. • The solution for betatron radiation detection was investigated.

  19. Betatron radiation based diagnostics for plasma wakefield accelerated electron beams at the SPARC-LAB test facility

    International Nuclear Information System (INIS)

    Shpakov, V.; Anania, M.P.; Biagioni, A.; Chiadroni, E.; Cianchi, A.; Curcio, A.; Dabagov, S.; Ferrario, M.; Filippi, F.; Marocchino, A.; Paroli, B.; Pompili, R.; Rossi, A.R.; Zigler, A.

    2016-01-01

    Recent progress with wake-field acceleration has shown a great potential in providing high gradient acceleration fields, while the quality of the beams remains relatively poor. Precise knowledge of the beam size at the exit from the plasma and matching conditions for the externally injected beams are the key for improvement of beam quality. Betatron radiation emitted by the beam during acceleration in the plasma is a powerful tool for the transverse beam size measurement, being also non-intercepting. In this work we report on the technical solutions chosen at SPARC-LAB for such diagnostics tool, along with expected parameters of betatron radiation. - Highlights: • The betatron radiation parameters in SPARC-LAB wakefiled experiments were studied. • The differences with betatron radiation in other wake-field experiments were highlighted. • The solution for betatron radiation detection was investigated.

  20. Measurement of microwave radiation from electron beam in the atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Ohta, I.S.; Akimune, H. [Faculty of Science and Engineering, Konan University, Kobe 658-8501 (Japan); Fukushima, M.; Ikeda, D. [Institute of Cosmic Ray Research, University of Tokyo, Kashiwa, Chiba 277-8582 (Japan); Inome, Y. [Faculty of Science and Engineering, Konan University, Kobe 658-8501 (Japan); Matthews, J.N. [University of Utah, Salt Lake City, UT 4112-0830 (United States); Ogio, S. [Graduate School of Science, Osaka City University, Osaka 558-8585 (Japan); Sagawa, H. [Institute of Cosmic Ray Research, University of Tokyo, Kashiwa, Chiba 277-8582 (Japan); Sako, T. [Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya 464-8601 (Japan); Shibata, T. [High Energy Accelerator Research Organization (KEK), Tsukuba 305-0801 (Japan); Yamamoto, T., E-mail: tokonatu@konan-u.ac.jp [Faculty of Science and Engineering, Konan University, Kobe 658-8501 (Japan)

    2016-02-21

    We report the use of an electron light source (ELS) located at the Telescope Array Observatory in Utah, USA, to measure the isotropic microwave radiation from air showers. To simulate extensive air showers, the ELS emits an electron beam into the atmosphere and a parabola antenna system for the satellite communication is used to measure the microwave radiation from the electron beam. Based on this measurement, an upper limit on the intensity of a 12.5 GHz microwave radiation at 0.5 m from a 10{sup 18} eV air shower was estimated to be 3.96×10{sup −16} W m{sup −2} Hz{sup −1} with a 95% confidence level.

  1. Measurement of secondary radiation during ion beam therapy with the pixel detector Timepix

    Science.gov (United States)

    Martišíková, Mária; Jakubek, Jan; Granja, Carlos; Hartmann, Bernadette; Opálka, Lukáš; Pospíšil, Stanislav; Jäkel, Oliver

    2011-11-01

    In ion beam therapy the finite range of the ion beams in tissue and the presence of the Bragg-peak are exploited. Unpredictable changes in the patient`s condition can alter the range of the ion beam in the body. Therefore it is desired to verify the actual ion range during the treatment, preferably in a non-invasive way. Positron emission tomography (PET) has been used successfully to monitor the applied dose distributions. This method however suffers from limited applicability and low detection efficiency. In order to increase the detection efficiency and to decrease the uncertainties, in this study we investigate the possibility to measure secondary charged particles emerging from the patient during irradiation. An initial experimental study to register the particle radiation coming out of a patient phantom during the therapy was performed at the Heidelberg Ion Beam Therapy Center (HIT) in Germany. A static narrowly-focused beam of carbon ions was directed into a head phantom. The emerging secondary radiation was measured with the position-sensitive Timepix detector outside of the phantom. The detector, developed by the Medipix Collaboration, consists of a silicon sensor bump bonded to a pixelated readout chip (256 × 256 pixels with 55 μm pitch). Together with the USB-based readout interface, Timepix can operate as an active nuclear emulsion registering single particles online with 2D-track visualization. In this contribution we measured the signal behind the head phantom and investigated its dependence on the beam energy (corresponding to beam range in water 2-30 cm). Furthermore, the response was measured at four angles between 0 and 90 degrees. At all investigated energies some signal was registered. Its pattern corresponds to ions. Differences in the total amount of signal for different beam energies were observed. The time-structure of the signal is correlated with that of the incoming beam, showing that we register products of prompt processes. Such

  2. Measurement of secondary radiation during ion beam therapy with the pixel detector Timepix

    International Nuclear Information System (INIS)

    Martišíková, Mária; Hartmann, Bernadette; Jäkel, Oliver; Jakubek, Jan; Granja, Carlos; Opálka, Lukáš; Pospíšil, Stanislav

    2011-01-01

    In ion beam therapy the finite range of the ion beams in tissue and the presence of the Bragg-peak are exploited. Unpredictable changes in the patient's condition can alter the range of the ion beam in the body. Therefore it is desired to verify the actual ion range during the treatment, preferably in a non-invasive way. Positron emission tomography (PET) has been used successfully to monitor the applied dose distributions. This method however suffers from limited applicability and low detection efficiency. In order to increase the detection efficiency and to decrease the uncertainties, in this study we investigate the possibility to measure secondary charged particles emerging from the patient during irradiation. An initial experimental study to register the particle radiation coming out of a patient phantom during the therapy was performed at the Heidelberg Ion Beam Therapy Center (HIT) in Germany. A static narrowly-focused beam of carbon ions was directed into a head phantom. The emerging secondary radiation was measured with the position-sensitive Timepix detector outside of the phantom. The detector, developed by the Medipix Collaboration, consists of a silicon sensor bump bonded to a pixelated readout chip (256 × 256 pixels with 55 μm pitch). Together with the USB-based readout interface, Timepix can operate as an active nuclear emulsion registering single particles online with 2D-track visualization. In this contribution we measured the signal behind the head phantom and investigated its dependence on the beam energy (corresponding to beam range in water 2–30 cm). Furthermore, the response was measured at four angles between 0 and 90 degrees. At all investigated energies some signal was registered. Its pattern corresponds to ions. Differences in the total amount of signal for different beam energies were observed. The time-structure of the signal is correlated with that of the incoming beam, showing that we register products of prompt processes. Such

  3. Effect of heme oxygenase-1 on radiation-induced skin injury

    International Nuclear Information System (INIS)

    Song Chuanjun; Meng Xingjun; Xie Ling; Chen Qing; Zhou Jundong; Zhang Shuyu; Wu Jinchang

    2012-01-01

    Objective: To investigate the effect of heme oxygenase-1 (HO-1) on the acute radiation-induced skin injury by gene transfer. Methods: Thirty-three male SD rats were randomly divided into three groups as PBS-injected group, Ad-EGFP-injected group and Ad-HO-1-injected group (n=11). In each group, three rats were used for determining the expression of target gene and the other rats were irradiated on the buttock skin with 40 Gy electron beam generated by a linear accelerator. Immediately after irradiation, rats were administered with a subcutaneous injection of PBS, Ad-EGFP or Ad-HO-1, respectively. Subsequently, the skin reactions were measured twice a week using the semi-quantitative skin injury scale. Results: The strong positive expression of HO-1 was observed in subcutaneous dermal tissue after injection of Ad-HO-1. Compared to the PBS-injected group or the Ad-EGFP-injected group, a significant mitigation of skin injury was observed in Ad-HO-1-injected mice 14 d after irradiation (q=0.000-0.030, P<0.05). Conclusions: HO-1 could significantly mitigate radiation-induced acute skin injury and Ad-HO-1 could be used to treat radiation-induced skin injury. (authors)

  4. Radiation Induced Grafting of Acrylate onto Waste Rubber: The Effect of Monomer Type

    Directory of Open Access Journals (Sweden)

    Shirajuddin Siti Salwa M.

    2017-01-01

    Full Text Available The effect of three different acrylate group monomers, namely n-butyl acrylate, methacrylic acid and tripropylene glycol diacrylate of radiation induced grafting onto waste rubber was studied. The electron beam accelerator operated at voltage of 2MeV was used to irradiate the waste rubber at 10 kGy and 100 kGy absorbed radiation dose, respectively. The formation of grafting was observed from the increase in the grafting yield and confirmed by Transformed Infra-Red Spectroscopy results. According to the result obtained, only tripropylene glycol diacrylate was selected to graft onto waste rubber. The carbonyl bond from acrylate groups was seen at 1726 cm-1 band which confirmed the presence of TPGDA in the polymer matrix. This indicates the successful preparation of the TPGDA-grafted waste rubber via radiation induced grafting techniques.

  5. Scattered radiation in fan beam imaging systems

    International Nuclear Information System (INIS)

    Johns, P.C.; Yaffe, M.

    1982-01-01

    Scatter-to-primary energy fluence ratios (S/P) have been studied for fan x-ray beams as used in CT scanners and slit projection radiography systems. The dependence of S/P on phantom diameter, distance from phantom to image receptor, and kilovoltage is presented. An empirical equation is given that predicts S/P over a wide range of fan beam imaging configurations. For CT body scans on a 4th-generation machine, S/P is approximately 5%. Scattered radiation can produce a significant cupping artefact in CT images which is similar to that due to beam hardening. When multiple slices are used in scanned slit radiography, they can be arranged such that the increase in S/P is negligible. Calculations of scatter-to-primary ratios for first order scattering showed that for fan beams the contribution of coherent scatter is comparable to or greater than that of incoherent first scatter

  6. Behavioral changes induced by single and multiple electron beam pulses

    International Nuclear Information System (INIS)

    Pease, V.P.; McNulty, P.J.

    1985-01-01

    The effects of single, and low-dose, high-dose-rate and multiple electron beam pulses on passive avoidance behavior in mice were studied. Passive avoidance was measured by recording the time that an animal took to enter a chamber from a narrow platform. There were four conditions in the experiment: (1) no shock no radiation-control, (2) radiation only, (3) shock only, and (4) radiation plus shock. Forty animals were run for each data point. Dose rate was held constant at 9 x 10/sup 7/ rads/sec. Average doses for the two single pulses were 7.18 and 8.72 rads. The average total dose for a 25 pulse per second condition was 324.0 rads. The differences between the single versus multiple pulse radiation-only conditions were significant with longer avoidance latencies in the multiple pulse condition. Avoidance latencies were also significantly longer in the shock plus radiation condition for the multiple beam pulse than the single pulse. It is concluded that single and multiple electron beam pulses significantly effect behavior, in this case producing avoidance

  7. Radiation-induced thermoacoustic imaging

    International Nuclear Information System (INIS)

    Bowen, T.

    1984-01-01

    This invention provides a new technique for obtaining information non-invasively on the composition and structures of a material or body by detecting radiation-induced thermoacoustic image features. This is accomplished by utilizing the acoustic wave generated by sudden thermal stress. The sudden thermal stress is induced by a pulse of radiation which deposits energy causing a rapid, but very small, rise of temperature (typically, ΔT approximately 10sup(-6) - 10sup(-5) deg C). The radiation may be ionizing radiation, such as high energy electrons, photons (x-rays), neutrons, or other charged particles or it may be non-ionizing radiation, such as R.F. and microwave electromagnetic radiation and ultrasonic radiation. The choice of radiation depends on the nature of the body to be imaged and the type of information desired

  8. Delayed damage after radiation therapy for head and neck cancer

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, Yoshiyuki [Osaka Dental Univ., Hirakata (Japan)

    2000-03-01

    I investigated radiation damage, including osteoradionecrosis, arising from tooth extraction in fields that had received radiation therapy for head and neck cancer, and evaluated the effectiveness of pilocarpine for xerostomia. Between January 1990 and April 1996, I examined 30 patients for bone changes after tooth extraction in fields irradiated at the Department of Oral Radiology, Osaka Dental University Hospital. Nineteen of the patients had been treated for nasopharyngeal cancer and 11 for oropharyngeal cancer. Between January and April 1996, 4 additional patients were given pilocarpine hydrochloride (3-mg, 6-mg and 9-mg of KSS-694 orally three times a day) for 12 weeks and evaluated every 4 weeks as a base line. One had been treated for nasopharyngeal carcinoma, two for cancer of the cheek and one for an unknown carcinoma. Eighteen of the patients (11 with nasopharyngeal carcinoma and 7 with oropharyngeal carcinoma) had extractions. Use of preoperative and postoperative radiographs indicated that damage to the bone following tooth extraction after radiation exposure was related to whether antibiotics were administered the day before the extraction, whether forceps or elevators were used, and whether the tooth was in the field of radiation. Xerostomia improved in all 4 of the patients who received 6-mg or 9-mg of pilocarpine. It improved saliva production and relieved the symptoms of xerostomia after radiation therapy for head and neck cancer, although there were minor side effects such as fever. This information can be used to improve the oral environment of patients who have received radiation therapy for head and neck cancer, and to better understand their oral environment. (author)

  9. Delayed damage after radiation therapy for head and neck cancer

    International Nuclear Information System (INIS)

    Matsumoto, Yoshiyuki

    2000-01-01

    I investigated radiation damage, including osteoradionecrosis, arising from tooth extraction in fields that had received radiation therapy for head and neck cancer, and evaluated the effectiveness of pilocarpine for xerostomia. Between January 1990 and April 1996, I examined 30 patients for bone changes after tooth extraction in fields irradiated at the Department of Oral Radiology, Osaka Dental University Hospital. Nineteen of the patients had been treated for nasopharyngeal cancer and 11 for oropharyngeal cancer. Between January and April 1996, 4 additional patients were given pilocarpine hydrochloride (3-mg, 6-mg and 9-mg of KSS-694 orally three times a day) for 12 weeks and evaluated every 4 weeks as a base line. One had been treated for nasopharyngeal carcinoma, two for cancer of the cheek and one for an unknown carcinoma. Eighteen of the patients (11 with nasopharyngeal carcinoma and 7 with oropharyngeal carcinoma) had extractions. Use of preoperative and postoperative radiographs indicated that damage to the bone following tooth extraction after radiation exposure was related to whether antibiotics were administered the day before the extraction, whether forceps or elevators were used, and whether the tooth was in the field of radiation. Xerostomia improved in all 4 of the patients who received 6-mg or 9-mg of pilocarpine. It improved saliva production and relieved the symptoms of xerostomia after radiation therapy for head and neck cancer, although there were minor side effects such as fever. This information can be used to improve the oral environment of patients who have received radiation therapy for head and neck cancer, and to better understand their oral environment. (author)

  10. Cell killing and chromosomal aberration induced by heavy-ion beams in cultured human tumor cells

    International Nuclear Information System (INIS)

    Takakura, K.; Funada, A.; Mohri, M.; Lee, R.; Aoki, M.; Furusawa, Y.; Gotoh, E.

    2003-01-01

    Full text: To clarify the relation between cell death and chromosomal aberration in cultured human tumor cells irradaited with heavy-ion beams. The analyses were carried out on the basis of the linear energy transfer (LET) values of heavy ion beams as radiation source. Exponentially growing human tumor cells, Human Salivary Gland Tumor cells (HSG cells), were irradiated with various high energy heavy ions, such as 13 keV/micrometer carbon (C) ions as low LET charged particle radiation source, 120 keV/ micrometer carbon (C) ions and 440 keV/micrometer iron (Fe) ions as high LET charged particle radiation sources.The cell death was analysed by the colony formation method, and the chromosomal aberration and its repairing kinetics was analysed by prematurely chromosome condensation method (PCC method) using calyculin A. Chromatid-type breaks, isochromatid breaks and exchanges were scored for the samples from the cells keeping with various incubation time after irradiation. The LET dependence of the cell death was similar to that of the chromosome exchange formation after 12 hours incubation. A maximum peak was around 120 keV/micrometer. However it was not similar to the LET dependence of isochromatid breaks or chromatid breaks after 12 hours incubation. These results suggest that the exchanges formed in chromosome after irradiation should be one of essential causes to lead the cell death. The different quality of induced chromosome damage between high-LET and low-LET radiation was also shown. About 89 % and 88 % chromatid breaks induced by X rays and 13 keV/micrometer C ions were rejoined within 12 hours of post-irradiation, though only 71% and 58 % of chromatid breaks induced by 120 keV/micrometer C ions and 440 keV/micrometer Fe ions were rejoined within 12 hours of post-irradiation

  11. Radiation-induced segregation in model alloys

    Science.gov (United States)

    Ezawa, T.; Wakai, E.; Oshima, R.

    2000-12-01

    The dependence of the size factor of solutes on radiation-induced segregation (RIS) was studied. Ni-Si, Ni-Co, Ni-Cu, Ni-Mn, Ni-Pd, and Ni-Nb binary solid solution alloys were irradiated with electrons in a high voltage electron microscope at the same irradiation conditions. A focused beam and a grain boundary were utilized to generate a flow of point defects to cause RIS. From the concentration profile obtained by an energy dispersive X-ray analysis, the amount of RIS was calculated. The amount of RIS decreased as the size of the solute increased up to about 10%. However, as the size increased further, the amount of RIS increased. This result shows that RIS is not simply determined by the size effect rule.

  12. Dose–response analysis of parotid gland function: What is the best measure of xerostomia?

    International Nuclear Information System (INIS)

    Miah, Aisha B.; Gulliford, Sarah L.; Clark, Catharine H.; Bhide, Shreerang A.; Zaidi, Shane H.; Newbold, Kate L.; Harrington, Kevin J.; Nutting, Christopher M.

    2013-01-01

    Purpose: To describe the dose–response relationships for the different measures of salivary gland recovery following radical radiotherapy for locally advanced head and neck squamous cell cancers (LA-HNSCC). Methods and materials: Dosimetric analysis of data from the PARSPORT trial, a Phase III study of conventional RT (RT) and intensity modulated radiotherapy (IMRT) for LA-HNSCC was undertaken to determine the relationship between parotid gland mean dose and toxicity endpoints: high-grade subjective and objective xerostomia and xerostomia-related quality of life scores. LKB-NTCP parameters (TD50, m and n) were generated and tolerance doses (D50) reported using non-linear logistic regression analysis. Results: Data were available on 63 patients from the PARSPORT trial. Parotid saliva flow rate provided the strongest association between mean dose and recovery, D50 = 23.4 Gy (20.6–26.2) and k = 3.2 (1.9–4.5), R 2 = 0.85. Corresponding LKB parameters were TD50 = 26.3 Gy (95% CI: 24.0–30.1), m = 0.25 (0.18–1.0 and n = 1). LENTSOMA subjective xerostomia also demonstrated a strong association D50 = 33.3 Gy (26.7–39.8), k = 2.8 (91.4–4.4), R 2 = 0.77). Conclusion: We recommend using the LENT SOMA subjective xerostomia score to predict recovery of salivation due to its strong association with dosimetry and ease of recording

  13. Salivary Gland Dysplasia in Fgf10 Heterozygous Mice: A New Mouse Model of Xerostomia

    Science.gov (United States)

    May, A.J.; Chatzeli, L.; Proctor, G.B.; Tucker, A.S.

    2017-01-01

    Xerostomia, or chronic dry mouth, is a common syndrome caused by a lack of saliva that can lead to severe eating difficulties, dental caries and oral candida infections. The prevalence of xerostomia increases with age and affects approximately 30% of people aged 65 or older. Given the large numbers of sufferers, and the potential increase in incidence given our aging population, it is important to understand the complex mechanisms that drive hyposalivation and the consequences for the dentition and oral mucosa. From this study we propose the Fgf10 +/- mouse as a model to investigate xerostomia. By following embryonic salivary gland development, in vivo and in vitro, we show that a reduction in Fgf10 causes a delay in branching of salivary glands. This leads to hypoplasia of the glands, a phenotype that is not rescued postnatally or by adulthood in both male and female Fgf10 +/- mice. Histological analysis of the glands showed no obvious defect in cellular differentiation or acini/ductal arrangements, however there was a significant reduction in their size and weight. Analysis of saliva secretion showed that hypoplasia of the glands led to a significant reduction in saliva production in Fgf10 +/- adults, giving rise to a reduced saliva pellicle in the oral cavity of these mice. Mature mice were shown to drink more and in many cases had severe tooth wear. The Fgf10 +/- mouse is therefore a useful model to explore the causes and effects of xerostomia. PMID:26321752

  14. Dose-response analysis of parotid gland function: what is the best measure of xerostomia?

    Science.gov (United States)

    Miah, Aisha B; Gulliford, Sarah L; Clark, Catharine H; Bhide, Shreerang A; Zaidi, Shane H; Newbold, Kate L; Harrington, Kevin J; Nutting, Christopher M

    2013-03-01

    To describe the dose-response relationships for the different measures of salivary gland recovery following radical radiotherapy for locally advanced head and neck squamous cell cancers (LA-HNSCC). Dosimetric analysis of data from the PARSPORT trial, a Phase III study of conventional RT (RT) and intensity modulated radiotherapy (IMRT) for LA-HNSCC was undertaken to determine the relationship between parotid gland mean dose and toxicity endpoints: high-grade subjective and objective xerostomia and xerostomia-related quality of life scores. LKB-NTCP parameters (TD50, m and n) were generated and tolerance doses (D50) reported using non-linear logistic regression analysis. Data were available on 63 patients from the PARSPORT trial. Parotid saliva flow rate provided the strongest association between mean dose and recovery, D50=23.4 Gy (20.6-26.2) and k=3.2 (1.9-4.5), R(2)=0.85. Corresponding LKB parameters were TD50=26.3 Gy (95% CI: 24.0-30.1), m=0.25 (0.18-1.0 and n=1). LENTSOMA subjective xerostomia also demonstrated a strong association D50=33.3 Gy (26.7-39.8), k=2.8 (91.4-4.4), R(2)=0.77). We recommend using the LENT SOMA subjective xerostomia score to predict recovery of salivation due to its strong association with dosimetry and ease of recording. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  15. Salivary Gland Dysplasia in Fgf10 Heterozygous Mice: A New Mouse Model of Xerostomia.

    Science.gov (United States)

    May, A J; Chatzeli, L; Proctor, G B; Tucker, A S

    2015-01-01

    Xerostomia, or chronic dry mouth, is a common syndrome caused by a lack of saliva that can lead to severe eating difficulties, dental caries and oral candida infections. The prevalence of xerostomia increases with age and affects approximately 30% of people aged 65 or older. Given the large numbers of sufferers, and the potential increase in incidence given our aging population, it is important to understand the complex mechanisms that drive hyposalivation and the consequences for the dentition and oral mucosa. From this study we propose the Fgf10 +/- mouse as a model to investigate xerostomia. By following embryonic salivary gland development, in vivo and in vitro, we show that a reduction in Fgf10 causes a delay in branching of salivary glands. This leads to hypoplasia of the glands, a phenotype that is not rescued postnatally or by adulthood in both male and female Fgf10 +/- mice. Histological analysis of the glands showed no obvious defect in cellular differentiation or acini/ductal arrangements, however there was a significant reduction in their size and weight. Analysis of saliva secretion showed that hypoplasia of the glands led to a significant reduction in saliva production in Fgf10 +/- adults, giving rise to a reduced saliva pellicle in the oral cavity of these mice. Mature mice were shown to drink more and in many cases had severe tooth wear. The Fgf10 +/- mouse is therefore a useful model to explore the causes and effects of xerostomia.

  16. The management of xerostomia in patients on haemodialysis: comparison of artificial saliva and chewing gum.

    Science.gov (United States)

    Bots, Casper P; Brand, Henk S; Veerman, Enno C I; Valentijn-Benz, Marianne; Van Amerongen, Barbara M; Nieuw Amerongen, Arie V; Valentijn, Robert M; Vos, Pieter F; Bijlsma, Joost A; Bezemer, Pieter D; ter Wee, Piet M

    2005-04-01

    Many patients on haemodialysis (HD) therapy suffer from a dry mouth and xerostomia. This can be relieved by mechanical and gustatory stimulation or palliative care. The aim of this crossover study was to investigate the effect and preferences of a sugar-free chewing gum (Freedent White) and a xanthan gum-based artificial saliva (Xialine) in the management of xerostomia in chronic HD patients. Sixty-five HD patients participated in a 6-week crossover trial. The artificial saliva was rated significantly lower than the chewing gum for effectiveness, taste and a global assessment. No preference differences were found for gender and age, although older subjects rated the artificial saliva with a higher mark. Thirty-nine subjects (60%) preferred chewing gum, 15% (n=10) preferred the artificial saliva. Therefore, both chewing gum and artificial saliva could play an important role in the palliative care of xerostomia in HD patients.

  17. Effects of mouthwash interventions on xerostomia and unstimulated whole saliva flow rate among hemodialysis patients: A randomized controlled study.

    Science.gov (United States)

    Yu, I-Chen; Tsai, Yun-Fang; Fang, Ji-Tseng; Yeh, Mei-Ming; Fang, Jia-You; Liu, Chieh-Yu

    2016-11-01

    Dry mouth (xerostomia) is a common symptom in hemodialysis patients, which is associated with a reduced salivary flow. Xerostomia affects patients' oral health and quality of life. The aim of this study was to investigate using a mouthwash as a means to reduce xerostomia and improve saliva flow rates in hemodialysis patients. A randomized controlled trial. Three dialysis centers in Northern Taiwan served as the study sites. Patients were purposively sampled from three hemodialysis centers in Taiwan and randomly assigned to one of three groups: pure water mouthwash; n=41, licorice mouthwash; n=44, or no mouthwash (control); n=37. The Summated Xerostomia Inventory, and unstimulated whole salivary flow rate measured dry mouth and salivary flow, respectively. Data was collected at baseline, dialysis Day 5 and Day 10. One hundred twenty-two patients participated in this study. Baselines were adjusted for any imbalances in variables and generalized estimating equations analysed the data. Compared to control, a pure water mouthwash resulted in an increase in the unstimulated salivary flow rate of 25.85×10 -3 mL/min and 25.78×10 -3 mL/min (pXerostomia Inventory scores. The licorice mouthwash also significantly improved the unstimulated salivary flow rates to 114.92×10 -3 mL/min, and 131.61×10 -3 mL/min at Day 5 and Day 10, respectively (pXerostomia Inventory (pxerostomia. This suggests the use of a licorice mouthwash may effectively relieve feelings of dry mouth in hemodialysis patients. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Analysis of late toxicity in nasopharyngeal carcinoma patients treated with intensity modulated radiation therapy

    International Nuclear Information System (INIS)

    Zheng, YingJie; Han, Fei; Xiao, WeiWei; Xiang, YanQun; Lu, LiXia; Deng, XiaoWu; Cui, NianJi; Zhao, Chong

    2015-01-01

    To observe the late toxicities in nasopharyngeal carcinoma (NPC) patients who achieved long-term survival after intensity modulated radiation therapy (IMRT). 208 untreated NPC patients who received IMRT and survived more than five years with locoregional disease control and no metastasis were evaluated in this study. The prescription dose to the gross target volume of nasopharynx (GTVnx), positive neck lymph nodes (GTVnd), clinical target volume 1 (CTV1) and 2 (CTV2) was 68Gy/30f, 60-66Gy/30f, 60 Gy/30f and 54Gy/30f, respectively. The nasopharynx and upper neck targets were irradiated using IMRT, and the lower neck and supraclavicular fossae targets were irradiated using the half-beam technique with conventional irradiation. The late toxicities were evaluated according to the LENT/SOMA criteria of 1995. The median follow-up time was 78 months (60–96 months). The occurrence rates of cervical subcutaneous fibrosis, hearing loss, skin dystrophy, xerostomia, trismus, temporal lobe injury, cranial nerve damage, cataract, and brain stem injury induced by radiotherapy were 89.9%, 67.8%, 47.6%, 40.9%, 7.21%, 4.33%, 2.88%, 1.44%, and 0.48%, respectively. No spinal cord injury and mandible damage were found. Grade 3–4 late injuries were observed as follows: 1 (0.48%) skin dystrophy, 4 (1.92%) cervical subcutaneous fibrosis, 2 (0.96%) hearing loss, 2 (0.96%) cranial nerve palsy, and 1 (0.48%) temporal lobe necrosis. No grade 3–4 late injuries occurred in parotid, temporomandibular joints and eyes. Xerostomia decreased gradually over time and then showed only slight changes after 4 years. The change in the incisor distance stabilised by 1 year after RT, however, the incidence of hearing loss, skin dystrophy, subcutaneous fibrosis and nervous system injuries increased over time after RT. The late injuries in most NPC patients who had long-term survivals after IMRT are alleviated. Within the 5 years of follow-up, we found xerostomia decreased gradually; The change in the

  19. Beam-Induced Damage Mechanisms and their Calculation

    CERN Document Server

    Bertarelli, A

    2016-01-01

    The rapid interaction of highly energetic particle beams with matter induces dynamic responses in the impacted component. If the beam pulse is sufficiently intense, extreme conditions can be reached, such as very high pressures, changes of material density, phase transitions, intense stress waves, material fragmentation and explosions. Even at lower intensities and longer time-scales, significant effects may be induced, such as vibrations, large oscillations, and permanent deformation of the impacted components. These lectures provide an introduction to the mechanisms that govern the thermomechanical phenomena induced by the interaction between particle beams and solids and to the analytical and numerical methods that are available for assessing the response of impacted components. An overview of the design principles of such devices is also provided, along with descriptions of material selection guidelines and the experimental tests that are required to validate materials and components exposed to interactio...

  20. Spontaneous and stimulated emission induced by an electron, electron bunch, and electron beam in a plasma

    International Nuclear Information System (INIS)

    Kuzelev, M V; Rukhadze, A A

    2008-01-01

    Two fundamental mechanisms - the Cherenkov effect and anomalous Doppler effect - underlying the emission by an electron during its superluminal motion in medium are considered. Cherenkov emission induced by a single electron and a small electron bunch is spontaneous. In the course of spontaneous Cherenkov emission, the translational motion of an electron is slowed down and the radiation energy grows linearly with time. As the number of radiating electrons increases, Cherenkov emission becomes stimulated. Stimulated Cherenkov emission represents a resonance beam instability. This emission process is accompanied by longitudinal electron bunching in the beam or by the breaking of an electron bunch into smaller bunches, in which case the radiation energy grows exponentially with time. In terms of the longitudinal size L e of the electron bunch there is a transition region λ e 0 -1 between the spontaneous and stimulated Cherenkov effects, where λ is the average radiation wavelength, and δ 0 is the dimensionless (in units of the radiation frequency) growth rate of the Cherenkov beam instability. The range to the left of this region is dominated by spontaneous emission, whereas the range to the right of this region is dominated by stimulated emission. In contrast to the Vavilov-Cherenkov effect, the anomalous Doppler effect should always (even for a single electron) be considered as stimulated, because it can only be explained by accounting for the reverse action of the radiation field on the moving electron. During stimulated emission in conditions where anomalous Doppler effect shows itself, an electron is slowed down and spins up; in this case, the radiation energy grows exponentially with time. (reviews of topical problems)

  1. Intense heavy ion beam-induced effects in carbon-based stripper foils

    Energy Technology Data Exchange (ETDEWEB)

    Kupka, Katharina

    2016-08-15

    Amorphous carbon or carbon-based stripper foils are commonly applied in accelerator technology for electron stripping of ions. At the planned facility for antiproton and ion research (FAIR) at the Helmholtzzentrum fuer Schwerionenforschung (GSI), Darmstadt, thin carbon stripper foils provide an option for directly delivering ions of intermediate charge states to the heavy ion synchrotron, SIS 18, in order to mitigate space charge limitations during high-intensity operation. In case of desired high end-energies in the synchrotron, a second stripping process by a thicker carbon foil provides ions of higher charge states for injection into the SIS18. High beam intensities and a pulsed beam structure as foreseen at FAIR pose new challenges to the stripper foils which experience enhanced degradation by radiation damage, thermal effects, and stress waves. In order to ensure reliable accelerator operation, radiation-hard stripper foils are required. This thesis aims to a better understanding of processes leading to degradation of carbon-based thin foils. Special focus is placed on ion-beam induced structure and physical property changes and on the influence of different beam parameters. Irradiation experiments were performed at the M3-beamline of the universal linear accelerator (UNILAC) at GSI, using swift heavy ion beams with different pulse lengths and repetition rates. Tested carbon foils were standard amorphous carbon stripper foils produced by the GSI target laboratory, as well as commercial amorphous and diamond-like carbon foils and buckypaper foils. Microstructural changes were investigated with various methods such as optical microscopy, scanning electron microscopy (SEM), profilometry and chromatic aberration measurements. For the investigation of structural changes X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, high resolution transmission electron microscopy (HRTEM), in-situ Fourier-transform infrared spectroscopy (FTIR) and small angle X

  2. Intense heavy ion beam-induced effects in carbon-based stripper foils

    International Nuclear Information System (INIS)

    Kupka, Katharina

    2016-08-01

    Amorphous carbon or carbon-based stripper foils are commonly applied in accelerator technology for electron stripping of ions. At the planned facility for antiproton and ion research (FAIR) at the Helmholtzzentrum fuer Schwerionenforschung (GSI), Darmstadt, thin carbon stripper foils provide an option for directly delivering ions of intermediate charge states to the heavy ion synchrotron, SIS 18, in order to mitigate space charge limitations during high-intensity operation. In case of desired high end-energies in the synchrotron, a second stripping process by a thicker carbon foil provides ions of higher charge states for injection into the SIS18. High beam intensities and a pulsed beam structure as foreseen at FAIR pose new challenges to the stripper foils which experience enhanced degradation by radiation damage, thermal effects, and stress waves. In order to ensure reliable accelerator operation, radiation-hard stripper foils are required. This thesis aims to a better understanding of processes leading to degradation of carbon-based thin foils. Special focus is placed on ion-beam induced structure and physical property changes and on the influence of different beam parameters. Irradiation experiments were performed at the M3-beamline of the universal linear accelerator (UNILAC) at GSI, using swift heavy ion beams with different pulse lengths and repetition rates. Tested carbon foils were standard amorphous carbon stripper foils produced by the GSI target laboratory, as well as commercial amorphous and diamond-like carbon foils and buckypaper foils. Microstructural changes were investigated with various methods such as optical microscopy, scanning electron microscopy (SEM), profilometry and chromatic aberration measurements. For the investigation of structural changes X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, high resolution transmission electron microscopy (HRTEM), in-situ Fourier-transform infrared spectroscopy (FTIR) and small angle X

  3. Topics in radiation at accelerators: Radiation physics for personnel and environmental protection

    International Nuclear Information System (INIS)

    Cossairt, J.D.

    1996-10-01

    In the first chapter, terminology, physical and radiological quantities, and units of measurement used to describe the properties of accelerator radiation fields are reviewed. The general considerations of primary radiation fields pertinent to accelerators are discussed. The primary radiation fields produced by electron beams are described qualitatively and quantitatively. In the same manner the primary radiation fields produced by proton and ion beams are described. Subsequent chapters describe: shielding of electrons and photons at accelerators; shielding of proton and ion accelerators; low energy prompt radiation phenomena; induced radioactivity at accelerators; topics in radiation protection instrumentation at accelerators; and accelerator radiation protection program elements

  4. Ion beam induced stress formation and relaxation in germanium

    Energy Technology Data Exchange (ETDEWEB)

    Steinbach, T., E-mail: Tobias.Steinbach@uni-jena.de [Institut für Festkörperphysik, Friedrich-Schiller-Universität Jena, Max-Wien-Platz 1, D-07743 Jena (Germany); Reupert, A.; Schmidt, E.; Wesch, W. [Institut für Festkörperphysik, Friedrich-Schiller-Universität Jena, Max-Wien-Platz 1, D-07743 Jena (Germany)

    2013-07-15

    Ion irradiation of crystalline solids leads not only to defect formation and amorphization but also to mechanical stress. In the past, many investigations in various materials were performed focusing on the ion beam induced damage formation but only several experiments were done to investigate the ion beam induced stress evolution. Especially in microelectronic devices, mechanical stress leads to several unwanted effects like cracking and peeling of surface layers as well as changing physical properties and anomalous diffusion of dopants. To study the stress formation and relaxation process in semiconductors, crystalline and amorphous germanium samples were irradiated with 3 MeV iodine ions at different ion fluence rates. The irradiation induced stress evolution was measured in situ with a laser reflection technique as a function of ion fluence, whereas the damage formation was investigated by means of Rutherford backscattering spectrometry. The investigations show that mechanical stress builds up at low ion fluences as a direct consequence of ion beam induced point defect formation. However, further ion irradiation causes a stress relaxation which is attributed to the accumulation of point defects and therefore the creation of amorphous regions. A constant stress state is reached at high ion fluences if a homogeneous amorphous surface layer was formed and no further ion beam induced phase transition took place. Based on the results, we can conclude that the ion beam induced stress evolution seems to be mainly dominated by the creation and accumulation of irradiation induced structural modification.

  5. Intraoperative electron beam radiation therapy (IOEBRT) for carcinoma of the exocrine pancreas

    International Nuclear Information System (INIS)

    Dobelbower, R.R. Jr.; Konski, A.A.; Merrick, H.W. III; Bronn, D.G.; Schifeling, D.; Kamen, C.

    1991-01-01

    The abdominal cavities of 50 patients were explored in a specially constructed intraoperative radiotherapy operating amphitheater at the Medical College of Ohio. Twenty-six patients were treated with intraoperative and postoperative precision high dose external beam therapy, 12 with intraoperative irradiation but no external beam therapy, and 12 with palliative surgery alone. All but two patients completed the postoperative external beam radiation therapy as initially prescribed. The median survival time for patients treated with palliative surgery alone was 4 months, and that for patients treated with intraoperative radiotherapy without external beam therapy was 3.5 months. Patients undergoing intraoperative irradiation and external beam radiation therapy had a median survival time of 10.5 months. Four patients died within 30 days of surgery and two patients died of gastrointestinal hemorrhage 5 months posttreatment

  6. Charged particle beam monitoring by means of synchrotron radiation

    International Nuclear Information System (INIS)

    Panasyuk, V.S.; Anevskij, S.I.

    1984-01-01

    Optical methods for monitoring the number of accelerated electrons and electron energy by means of beam synchrotron radiation (SR) as well as peculiarities of SR characteristics of beams with a small radius of the orbit are considered. Optical methods for charged particle beam monitoring are shown to ensure operative and precise monitoring the number of particles and particle energy. SR sources with large axial dimensions of an electron beam have specific spectral angular and polarization characteristics. If electron angular distribution at deflection from the median plane is noticeably wider than angular distribution of SR of a certain electron, relative SR characteristics of these soUrces are calculated with high accuracy

  7. Radiation induced degradation of DNA in photodynamic therapy of cancer

    International Nuclear Information System (INIS)

    Ion, Rodica; Scarlat, F.; Niculescu, V.I.R.; Scarlat, Fl.; Gunaydin, Keriman

    2001-01-01

    DNA is a critical cellular target for oxidative processes induced by physical and chemical stresses. It is known that the direct effect of ionizing radiation on DNA results mainly in base ionization and may lead to mutation, carcinogenesis and cell death. The degradation of DNA induced by laser and ionizing radiation (electron and photon beam) is analyzed in this paper. The ionizing radiation degradation of DNA is a radical process. A series of lesions among the major base degradation product has been measured in isolated DNA exposed to gamma radiation in aerated aqueous solution. Degradation can be accounted for by the formation of hydroxyl radicals upon radiolysis of water (indirect effect). The production of DNA damage by ionizing radiation involves two mechanisms, direct and indirect effects. Direct effect leads to ionization and excitation of DNA molecules, while indirect effect is due to the interaction of reactive species, in particular of OH radicals produced by water radiolysis, with targets in DNA. The relative contribution of the two mechanisms in damaging DNA depends on the type of radiation. Single strand breaks and base damage seem to be mainly produced by the attack of hydroxyl radicals on DNA, whereas double strand breaks result predominantly of direct energy deposition. The four bases are degraded in high yield. Direct effect has been mimicked by photo-induced electron abstraction from the bases producing their radical cation. The base damage may also occur from the formation of radical cation of purine and pyrimidine components. When DNA is irradiated in solution, single strand breaks are mainly due to the abstraction of an H atom from the 4 ' position of 2 ' -deoxyribose by the attack of OH radicals produced by water radiolysis. Quantification of the modified bases showed the guanine is the preferential target. Ionizing radiation induces several types of DNA modifications, including chain breaks, DNA-protein cross-links, oxidized DNA bases

  8. Protective Effect of HSP25 on Radiation Induced Tissue Damage

    International Nuclear Information System (INIS)

    Lee, Hae-June; Lee, Yoon-Jin; Kwon, Hee-Choong; Bae, Sang-Woo; Lee, Yun-Sil; Kim, Sung Ho

    2007-01-01

    Control of cancer by irradiation therapy alone or in conjunction with combination chemotherapy is often limited by organ specific toxicity. Ionizing irradiation toxicity is initiated by damage to normal tissue near the tumor target and within the transit volume of radiotherapy beams. Irradiation-induced cellular, tissue, and organ damage is mediated by acute effects, which can be dose limiting. A latent period follows recovery from the acute reaction, then chronic irradiation fibrosis (late effects) pose a second cause of organ failure. HSP25/27 has been suggested to protect cells against apoptotic cell death triggered by hyperthermia, ionizing radiation, oxidative stress, Fas ligand, and cytotoxic drugs. And several mechanisms have been proposed to account for HSP27-mediated apoptotic protection. However radioprotective effect of HSP25/27 in vivo system has not yet been evaluated. The aim of this study was to evaluate the potential of exogenous HSP25 expression, as delivered by adenoviral vectors, to protect animal from radiation induced tissue damage

  9. Salivary flow and xerostomia in patients with type 2 diabetes.

    Science.gov (United States)

    Carramolino-Cuéllar, Esther; Lauritano, Dorina; Silvestre, Francisco-Javier; Carinci, Francesco; Lucchese, Alberta; Silvestre-Rangil, Javier

    2018-05-01

    Saliva is secreted by the major and minor salivary glands. There are a number of physiological factors that can reduce this secretion such as age, sex, body weight, number of teeth present in the mouth or time of day. This decrease may also be caused by the use of certain drugs, radiotherapy for head and neck cancer, chronic rheumatic diseases such as Sjögren's syndrome and other systemic disorders such as diabetes mellitus (DM). Objective of this study was to investigate the effect of type 2 DM on salivary secretion and its relation to the sensation of xerostomia. Forty-seven patients with type 2 DM and 46 healthy individuals, aged 40-80, participated in the study. Samples of saliva were collected, at rest and after stimulation, at baseline and after the administration of a meal. A questionnaire of 10 items was used to define the patients' sensations of xerostomia. For statistical analysis, the Mann-Whitney test was used to assess the difference in salivary flow between the two groups and the relationship between the response to each of the questions and salivary flow levels. The degree of the patients' sensation of xerostomia was analysed by the Fisher test. There was a significant decrease in total saliva levels at rest in patients with type 2 DM compared to the control group. The study group also experienced higher levels of dryness at night and on waking as well as a greater sensation of lingual burning compared to the control group. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. Radioprotective Effect of Lidocaine on Function and Ultrastructure of Salivary Glands Receiving Fractionated Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Hakim, Samer George, E-mail: samer.hakim@mkg-chir.mu-luebeck.de [Department of Oral and Maxillofacial Surgery, University of Luebeck, Luebeck (Germany); Benedek, Geza Attila [Department of Oral and Maxillofacial Surgery, University of Luebeck, Luebeck (Germany); Su Yuxiong [Department of Oral and Maxillofacial Surgery, University of Luebeck, Luebeck (Germany); Department of Oral and Maxillofacial Surgery, Sun Yat-Sen University, Guanghua School of Stomatology, Guanghua (China); Jacobsen, Hans Christian [Department of Oral and Maxillofacial Surgery, University of Luebeck, Luebeck (Germany); Klinger, Matthias [Institute of Anatomy, University of Luebeck, Luebeck (Germany); Dendorfer, Andreas [Institute of Experimental and Clinical Pharmacology and Toxicology, University of Luebeck, Luebeck (Germany); Hemmelmann, Claudia [Institute of Medical Biometry and Statistics, University of Luebeck, Luebeck (Germany); Meller, Birgit [Department of Radiology and Nuclear Medicine, University of Luebeck, Luebeck (Germany); Nadrowitz, Roger; Rades, Dirk [Department of Radiation Oncology, University of Luebeck, Luebeck (Germany); Sieg, Peter [Department of Oral and Maxillofacial Surgery, University of Luebeck, Luebeck (Germany)

    2012-03-15

    Purpose: Radiation-induced xerostomia still represents a common side effect after radiotherapy for head-and-neck malignancies. The aim of the present study was to examine the radioprotective effect of lidocaine hydrochloride during fractionated radiation in an experimental animal model. Methods and Materials: To evaluate the influence of different radiation doses on salivary gland function and the radioprotective effect of lidocaine, rabbits were irradiated with 15, 25, 30, and 35 Gy (equivalent doses in 2-Gy fractions equivalent to 24, 40, 48, and 56 Gy, respectively). Lidocaine hydrochloride (10 and 12 mg/kg) was administered before every radiation fraction in the treatment groups. Salivary gland function was assessed by flow sialometry and sialoscintigraphy, and the morphologic changes were evaluated using transmission electron microscopy. Results: Functional impairment was first observed after 35 Gy and pretreatment with lidocaine improved radiation tolerance of both parotid and submandibular glands. The use of 12 mg/kg lidocaine was superior and displayed significant radioprotection with regard to flow sialometry and sialoscintigraphy. The ultrastructure was largely preserved after pretreatment with both lidocaine doses. Conclusions: Lidocaine represents an effective radioprotective agent and a promising approach for clinical application to avoid radiation-induced functional impairment of salivary glands.

  11. Radioprotective Effect of Lidocaine on Function and Ultrastructure of Salivary Glands Receiving Fractionated Radiation

    International Nuclear Information System (INIS)

    Hakim, Samer George; Benedek, Gèza Attila; Su Yuxiong; Jacobsen, Hans Christian; Klinger, Matthias; Dendorfer, Andreas; Hemmelmann, Claudia; Meller, Birgit; Nadrowitz, Roger; Rades, Dirk; Sieg, Peter

    2012-01-01

    Purpose: Radiation-induced xerostomia still represents a common side effect after radiotherapy for head-and-neck malignancies. The aim of the present study was to examine the radioprotective effect of lidocaine hydrochloride during fractionated radiation in an experimental animal model. Methods and Materials: To evaluate the influence of different radiation doses on salivary gland function and the radioprotective effect of lidocaine, rabbits were irradiated with 15, 25, 30, and 35 Gy (equivalent doses in 2-Gy fractions equivalent to 24, 40, 48, and 56 Gy, respectively). Lidocaine hydrochloride (10 and 12 mg/kg) was administered before every radiation fraction in the treatment groups. Salivary gland function was assessed by flow sialometry and sialoscintigraphy, and the morphologic changes were evaluated using transmission electron microscopy. Results: Functional impairment was first observed after 35 Gy and pretreatment with lidocaine improved radiation tolerance of both parotid and submandibular glands. The use of 12 mg/kg lidocaine was superior and displayed significant radioprotection with regard to flow sialometry and sialoscintigraphy. The ultrastructure was largely preserved after pretreatment with both lidocaine doses. Conclusions: Lidocaine represents an effective radioprotective agent and a promising approach for clinical application to avoid radiation-induced functional impairment of salivary glands.

  12. A detector for localizing diverging beams of ionizing radiations

    International Nuclear Information System (INIS)

    Allemand, Robert.

    1974-01-01

    Description is given of a detector for localizing diverging radiation beams, adapted to provide the angular distribution of nuclear events. That detector comprises a casing filled with a fluid adapted to produce electric charges under radiations and provided with a front-side and a rear-side, means for generating an electric field at right angles to portions of parallel surfaces of revolution having in common an axis of revolution contained in the place of symmetry, and a plane unit for localizing electric charges mounted at the rear of said means, the initial portion of the beam being on the axis of revolution. This can be applied to X-ray diffraction and to neutron diffraction [fr

  13. Radiation protection commissioning of neutron beam instruments at the OPAL research reactor

    International Nuclear Information System (INIS)

    Parkes, Alison; Saratsopoulos, John; Deura, Michael; Kenny, Pat

    2008-01-01

    The neutron beam facilities at the 20 MW OPAL Research Reactor were commissioned in 2007 and 2008. The initial suite of eight neutron beam instruments on two thermal neutron guides, two cold neutron guides and one thermal beam port located at the reactor face, together with their associated shielding were progressively installed and commissioned according to their individual project plans. Radiation surveys were systematically conducted as reactor power was raised in a step-wise manner to 20 MW in order to validate instrument shielding design and performance. The performance of each neutron guide was assessed by neutron energy spectrum and flux measurements. The activation of beam line components, decay times assessments and access procedures for Bragg Institute beam instrument scientists were established. The multiple configurations for each instrument and the influence of operating more than one instrument or beamline simultaneously were also tested. Areas of interest were the shielding around the secondary shutters, guide shield and bunker shield interfaces and monochromator doors. The shielding performance, safety interlock checks, improvements, radiation exposures and related radiation protection challenges are discussed. This paper discusses the health physics experience of commissioning the OPAL Research Reactor neutron beam facilities and describes health physics results, actions taken and lessons learned during commissioning. (author)

  14. Instrumentation for beam radiation and luminosity measurement in the CMS experiment using novel detector technologies

    CERN Document Server

    Guthoff, Moritz

    2017-01-01

    The higher energy and luminosity of the LHC initiated the development of dedicated technologies for radiation monitoring and luminosity measurement. A pixelated luminosity detector counts coincidences in several three layer telescopes of silicon pixel detectors to measure the luminosity for each colliding LHC bunch pair. In addition, charged particle tracking allows to monitor the location of the collision point.The upgraded fast beam conditions monitor measures the particle flux using 24 two pad single crystalline diamond sensors, equipped with a fast front-end ASIC produced in 130 nm CMOS technology. The excellent time resolution is used to separate collision products from machine induced background.A new beam-halo monitor at larger radius exploits Cerenkov light produced by relativistic charged particles in fused quartz crystals to provide direction sensitivity and time resolution to separate incoming and outgoing particles. The back-end electronics of the beam monitoring systems includes dedicated modules...

  15. Radiation-induced centers in inorganic glasses

    International Nuclear Information System (INIS)

    Brekhovskikh, S.M.; Tyul'nin, V.A.

    1988-01-01

    The nature, structure and formation mechanisms of radiation-induced colour centers, EPR, luminescence, generated ionizing radiation in nonorganic oxide glasses are considered. Experimental material covering both fundamental aspects of radiation physics and glass chemistry, and aspects intimately connected with the creation of new materials with the given radiation-spectral characteristics, with possibilities to prepare radiation-stable and radiation-sensitive glasses is systematized and generalized. Considerable attention is paid to the detection of radiation-induced center binding with composition, glass structures redox conditions for their synthesis. Some new possibilities of practical application of glasses with radiation-induced centers, in particular, to record optical information are reflected in the paper

  16. Method and apparatus to monitor a beam of ionizing radiation

    Science.gov (United States)

    Blackburn, Brandon W.; Chichester, David L.; Watson, Scott M.; Johnson, James T.; Kinlaw, Mathew T.

    2015-06-02

    Methods and apparatus to capture images of fluorescence generated by ionizing radiation and determine a position of a beam of ionizing radiation generating the fluorescence from the captured images. In one embodiment, the fluorescence is the result of ionization and recombination of nitrogen in air.

  17. Effect of radiation-induced amorphization on smectite dissolution.

    Science.gov (United States)

    Fourdrin, C; Allard, T; Monnet, I; Menguy, N; Benedetti, M; Calas, G

    2010-04-01

    Effects of radiation-induced amorphization of smectite were investigated using artificial irradiation. Beams of 925 MeV Xenon ions with radiation dose reaching 73 MGy were used to simulate the effects generated by alpha recoil nuclei or fission products in the context of high level nuclear waste repository. Amorphization was controlled by X-ray diffraction, transmission electron microscopy, and Fourier transform infrared spectroscopy. An important coalescence of the smectite sheets was observed which lead to a loss of interparticle porosity. The amorphization is revealed by a loss of long-range structure and accompanied by dehydroxylation. The dissolution rate far-from-equilibrium shows that the amount of silica in solution is two times larger in the amorphous sample than in the reference clay, a value which may be enhanced by orders of magnitude when considering the relative surface area of the samples. Irradiation-induced amorphization thus facilitates dissolution of the clay-derived material. This has to be taken into account for the safety assessment of high level nuclear waste repository, particularly in a scenario of leakage of the waste package which would deliver alpha emitters able to amorphize smectite after a limited period of time.

  18. Beam, vacuum and walls, a 3-body interaction

    International Nuclear Information System (INIS)

    Arianer, J.

    2002-11-01

    The interactions between beams of accelerated particles, residual gas and walls involve complex physical processes. In most cases these interactions affect the quality of the vacuum and the value of the pressure. This course reviews all these interactions in a pedagogical and practical way that may be useful for any user of devices involving beams of particles. This document is made up of 6 chapters: 1) basic notions (Maxwell-Boltzmann distribution, kinematics of charged particles, collisions, excitation and ionization), 2) properties of beams (emittance, local effects, and synchrotron radiation), 3) interactions between residual gas and particle beams (Bremsstrahlung radiation, energy loss due to ionization, charge shift of ion beams, photo-absorption and photo-ionization, and slowing-down in a plasma), 4) surface properties (crystal structure, and interaction between surface and the residual gas), 5) interaction between the beam and walls (reflection and diffraction of electrons, secondary emission of electrons, desorption induced by electron and ion impacts, photon production, ion-wall interaction, sputtering, ion penetration, surface ionization and thermal-ionization), and 6) radiation-wall interaction (diffusion, damping, photo-electric effect, desorption induced by photons, pair production and laser-surface interaction). (A.C.)

  19. An electron beam induced current study of gallium nitride and diamond materials

    International Nuclear Information System (INIS)

    Cropper, A.D.; Moore, D.J.; Scott, C.S.; Green, R.

    1995-01-01

    The continual need for microelectronic devices that operate under severe electronic and environmental conditions (high temperature, high frequency, high power, and radiation tolerance) has sustained research in wide bandgap semiconductor materials. The properties suggest these wide-bandgap semiconductor materials have tremendous potential for military and commercial applications. High frequency bipolar transistors and field effect transistors, diodes, and short wavelength optical devices have been proposed using these materials. Although research efforts involving the study of transport properties in Gallium Nitride (GaN) and Diamond have made significant advances, much work is still needed to improve the material quality so that the electrophysical behavior of device structures can be further understood and exploited. Electron beam induced current (EBIC) measurements can provide a method of understanding the transport properties in Gallium Nitride (GaN) and Diamond. This technique basically consists of measuring the current or voltage transient response to the drift and diffusion of carriers created by a short-duration pulse of radiation. This method differs from other experimental techniques because it is based on a fast transient electron beam probe created from a high speed, laser pulsed photoemission system

  20. Performance and perspectives of the diamond based Beam Condition Monitor for beam loss monitoring at CMS

    CERN Document Server

    AUTHOR|(CDS)2080862

    2015-01-01

    At CMS, a beam loss monitoring system is operated to protect the silicon detectors from high particle rates, arising from intense beam loss events. As detectors, poly-crystalline CVD diamond sensors are placed around the beam pipe at several locations inside CMS. In case of extremely high detector currents, the LHC beams are automatically extracted from the LHC rings.Diamond is the detector material of choice due to its radiation hardness. Predictions of the detector lifetime were made based on FLUKA monte-carlo simulations and irradiation test results from the RD42 collaboration, which attested no significant radiation damage over several years.During the LHC operational Run1 (2010 â?? 2013), the detector efficiencies were monitored. A signal decrease of about 50 times stronger than expectations was observed in the in-situ radiation environment. Electric field deformations due to charge carriers, trapped in radiation induced lattice defects, are responsible for this signal decrease. This so-called polarizat...

  1. The impact of xerostomia on oral-health-related quality of life among younger adults

    Science.gov (United States)

    Thomson, W Murray; Lawrence, Herenia P; Broadbent, Jonathan M; Poulton, Richie

    2006-01-01

    Background Recent research has suggested that chronic dry mouth affects the day-to-day lives of older people living in institutions. The condition has usually been considered to be a feature of old age, but recent work by our team produced the somewhat surprising finding that 10% of people in their early thirties are affected. This raises the issue of whether dry mouth is a trivial condition or a more substantial threat to quality of life among younger people. The objective of this study was to examine the association between xerostomia and oral-health-related quality of life among young adults while controlling for clinical oral health status and other potential confounding factors. Methods Cross-sectional analysis of data from a longstanding prospective observational study of a Dunedin (New Zealand) birth cohort: clinical dental examinations and questionnaires were used at age 32. The main measures were xerostomia (the subjective feeling of dry mouth, measured with a single question) and oral-health-related quality of life (OHRQoL) measured using the short-form Oral Health Impact Profile (OHIP-14). Results Of the 923 participants (48.9% female), one in ten were categorised as 'xerostomic', with no apparent gender difference. There was a strong association between xerostomia and OHRQoL (across all OHIP-14 domains) which persisted after multivariate analysis to control for clinical characteristics, gender, smoking status and personality characteristics (negative emotionality and positive emotionality). Conclusion Xerostomia is not a trivial condition; it appears to have marked and consistent effects on sufferers' day-to-day lives. PMID:17090332

  2. Xerostomia after radiotherapy. What matters - mean total dose or dose to each parotid gland?

    International Nuclear Information System (INIS)

    Tribius, S.; Sommer, J.; Prosch, C.; Bajrovic, A.; Kruell, A.; Petersen, C.; Muenscher, A.; Blessmann, M.; Todorovic, M.; Tennstedt, P.

    2013-01-01

    Purpose: Xerostomia is a debilitating side effect of radiotherapy in patients with head and neck cancer. We undertook a prospective study of the effect on xerostomia and outcomes of sparing one or both parotid glands during radiotherapy for patients with squamous cell carcinoma of the head and neck. Methods and materials: Patients with locally advanced squamous cell carcinoma of the head and neck received definitive (70 Gy in 2 Gy fractions) or adjuvant (60-66 Gy in 2 Gy fractions) curative-intent radiotherapy using helical tomotherapy with concurrent chemotherapy if appropriate. Group A received < 26 Gy to the left and right parotids and group B received < 26 Gy to either parotid. Results: The study included 126 patients; 114 (55 in group A and 59 in group B) had follow-up data. There were no statistically significant differences between groups in disease stage. Xerostomia was significantly reduced in group A vs. group B (p = 0.0381). Patients in group A also had significantly less dysphagia. Relapse-free and overall survival were not compromised in group A: 2-year relapse-free survival was 86% vs. 72% in group B (p = 0.361); 2-year overall survival was 88% and 76%, respectively (p = 0.251). Conclusion: This analysis suggests that reducing radiotherapy doses to both parotid glands to < 26 Gy can reduce xerostomia and dysphagia significantly without compromising survival. Sparing both parotids while maintaining target volume coverage and clinical outcome should be the treatment goal and reporting radiotherapy doses delivered to the individual parotids should be standard practice. (orig.)

  3. The impact of xerostomia on oral-health-related quality of life among younger adults

    Directory of Open Access Journals (Sweden)

    Broadbent Jonathan M

    2006-11-01

    Full Text Available Abstract Background Recent research has suggested that chronic dry mouth affects the day-to-day lives of older people living in institutions. The condition has usually been considered to be a feature of old age, but recent work by our team produced the somewhat surprising finding that 10% of people in their early thirties are affected. This raises the issue of whether dry mouth is a trivial condition or a more substantial threat to quality of life among younger people. The objective of this study was to examine the association between xerostomia and oral-health-related quality of life among young adults while controlling for clinical oral health status and other potential confounding factors. Methods Cross-sectional analysis of data from a longstanding prospective observational study of a Dunedin (New Zealand birth cohort: clinical dental examinations and questionnaires were used at age 32. The main measures were xerostomia (the subjective feeling of dry mouth, measured with a single question and oral-health-related quality of life (OHRQoL measured using the short-form Oral Health Impact Profile (OHIP-14. Results Of the 923 participants (48.9% female, one in ten were categorised as 'xerostomic', with no apparent gender difference. There was a strong association between xerostomia and OHRQoL (across all OHIP-14 domains which persisted after multivariate analysis to control for clinical characteristics, gender, smoking status and personality characteristics (negative emotionality and positive emotionality. Conclusion Xerostomia is not a trivial condition; it appears to have marked and consistent effects on sufferers' day-to-day lives.

  4. Xerostomia after radiotherapy. What matters - mean total dose or dose to each parotid gland?

    Energy Technology Data Exchange (ETDEWEB)

    Tribius, S.; Sommer, J.; Prosch, C.; Bajrovic, A.; Kruell, A.; Petersen, C. [University Medical Center Hamburg-Eppendorf, Hamburg (Germany). Dept. of Radiation Oncology; Muenscher, A. [University Medical Center Hamburg-Eppendorf, Hamburg (Germany). Dept. of Otorhinolaryngology and Head and Neck Surgery; Blessmann, M. [University Medical Center Hamburg-Eppendorf, Hamburg (Germany). Dept. of Oral and Maxillofacial Surgery; Todorovic, M. [University Medical Center Hamburg-Eppendorf, Hamburg (Germany). Dept. of Medical Physics; Tennstedt, P. [University Medical Center Hamburg-Eppendorf, Hamburg (Germany). Martini-Clinic, Prostate Cancer Center

    2013-03-15

    Purpose: Xerostomia is a debilitating side effect of radiotherapy in patients with head and neck cancer. We undertook a prospective study of the effect on xerostomia and outcomes of sparing one or both parotid glands during radiotherapy for patients with squamous cell carcinoma of the head and neck. Methods and materials: Patients with locally advanced squamous cell carcinoma of the head and neck received definitive (70 Gy in 2 Gy fractions) or adjuvant (60-66 Gy in 2 Gy fractions) curative-intent radiotherapy using helical tomotherapy with concurrent chemotherapy if appropriate. Group A received < 26 Gy to the left and right parotids and group B received < 26 Gy to either parotid. Results: The study included 126 patients; 114 (55 in group A and 59 in group B) had follow-up data. There were no statistically significant differences between groups in disease stage. Xerostomia was significantly reduced in group A vs. group B (p = 0.0381). Patients in group A also had significantly less dysphagia. Relapse-free and overall survival were not compromised in group A: 2-year relapse-free survival was 86% vs. 72% in group B (p = 0.361); 2-year overall survival was 88% and 76%, respectively (p = 0.251). Conclusion: This analysis suggests that reducing radiotherapy doses to both parotid glands to < 26 Gy can reduce xerostomia and dysphagia significantly without compromising survival. Sparing both parotids while maintaining target volume coverage and clinical outcome should be the treatment goal and reporting radiotherapy doses delivered to the individual parotids should be standard practice. (orig.)

  5. Internal and external generalizability of temporal dose-response relationships for xerostomia following IMRT for head and neck cancer.

    Science.gov (United States)

    Thor, Maria; Owosho, Adepitan A; Clark, Haley D; Oh, Jung Hun; Riaz, Nadeem; Hovan, Allan; Tsai, Jillian; Thomas, Steven D; Yom, Sae Hee K; Wu, Jonn S; Huryn, Joseph M; Moiseenko, Vitali; Lee, Nancy Y; Estilo, Cherry L; Deasy, Joseph O

    2017-02-01

    To study internal and external generalizability of temporal dose-response relationships for xerostomia after intensity-modulated radiotherapy (IMRT) for head and neck cancer, and to investigate potential amendments of the QUANTEC guidelines. Objective xerostomia was assessed in 121 patients (n Cohort1 =55; n Cohort2 =66) treated to 70Gy@2Gy in 2006-2015. Univariate and multivariate analyses (UVA, MVA with 1000 bootstrap populations) were conducted in Cohort1, and generalizability of the best-performing MVA model was investigated in Cohort2 (performance: AUC, p-values, and Hosmer-Lemeshow p-values (p HL )). Ultimately and for clinical guidance, minimum mean dose thresholds to the contralateral and the ipsilateral parotid glands (Dmean contra , Dmean ipsi ) were estimated from the generated dose-response curves. The observed xerostomia rate was 38%/47% (3months) and 19%/23% (11-12months) in Cohort1/Cohort2. Risk of xerostomia at 3months increased for higher Dmean contra and Dmean ipsi (Cohort1: 0.17·Dmean contra +0.11·Dmean ipsi -8.13; AUC=0.90±0.05; p=0.0002±0.002; p HL =0.22±0.23; Cohort2: AUC=0.81; pxerostomia following IMRT. Our results also suggest decreasing Dmean contra to below 20Gy, while keeping Dmean ipsi to around 25Gy. Long-term xerostomia was less frequent, and no dose-response relationship was established for this follow-up time. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  6. Radiation damage in the diamond based beam condition monitors of the CMS experiment at the Large Hadron Collider (LHC) at CERN

    Science.gov (United States)

    Guthoff, Moritz; Afanaciev, Konstantin; Dabrowski, Anne; de Boer, Wim; Lange, Wolfgang; Lohmann, Wolfgang; Stickland, David

    2013-12-01

    The Beam Condition Monitor (BCM) of the CMS detector at the LHC is a protection device similar to the LHC Beam Loss Monitor system. While the electronics used is the same, poly-crystalline Chemical Vapor Deposition (pCVD) diamonds are used instead of ionization chambers as the BCM sensor material. The main purpose of the system is the protection of the silicon Pixel and Strip tracking detectors by inducing a beam dump, if the beam losses are too high in the CMS detector. By comparing the detector current with the instantaneous luminosity, the BCM detector efficiency can be monitored. The number of radiation-induced defects in the diamond, reduces the charge collection distance, and hence lowers the signal. The number of these induced defects can be simulated using the FLUKA Monte Carlo simulation. The cross-section for creating defects increases with decreasing energies of the impinging particles. This explains, why diamond sensors mounted close to heavy calorimeters experience more radiation damage, because of the high number of low energy neutrons in these regions. The signal decrease was stronger than expected from the number of simulated defects. Here polarization from trapped charge carriers in the defects is a likely candidate for explaining the difference, as suggested by Transient Current Technique (TCT) measurements. A single-crystalline (sCVD) diamond sensor shows a faster relative signal decrease than a pCVD sensor mounted at the same location. This is expected, since the relative increase in the number of defects is larger in sCVD than in pCVD sensors.

  7. Xerostomia After Treatment for Oral and Oropharyngeal Cancer Using the University of Washington Saliva Domain and a Xerostomia-Related Quality-of-Life Scale

    International Nuclear Information System (INIS)

    Rogers, Simon N.; Johnson, Ian A.; Lowe, Derek

    2010-01-01

    Purpose: The first aim of this study was to identify which clinical factors are associated with xerostomia in patients after treatment for oral and oropharyngeal squamous cell carcinoma, using the Xerostomia-Related Quality-of-Life Scale (XeQoLS) and the University of Washington Quality-of-Life Questionnaire Version 4 dry mouth item (UW-QOL v4). The second aim was to compare these two questionnaires and postulate a cutoff in the UW-QOL below which patients are doing sufficient badly to warrant further evaluation and support. Methods and Materials: In all, 371 patients alive and disease free treated between 1992 and 2005 were sent the survey, of whom 250 (67%) responded. Various clinical factors correlated with xerostomia, particularly adjuvant radiotherapy and Pstage. Results: In logistic regression analyses to predict three or more problems on the XeQoLS, only adjuvant radiotherapy (p < 0.001) was significant at the 5% level. There were significant (p < 0.001) correlations between the XeQoLS scores (total average and domain) with all the UW-QOL domain scores, the strongest with swallowing (-0.69), taste (-0.64), chewing (-0.64), mood (-0.60), and saliva (-0.59) domains. Patients scoring <70 (i.e., 0 or 30) on the UW-QOL could be used as a screening cutoff because it formed 1 in 5 of all patients (49/242) but accounted for half (299/566) of the significant problems generated by the XeQoLS. This also identified 13/21 patients with 10 or more problems. Conclusion: The UW-QOL saliva domain seems to be a suitable means of screening for dry mouth in head-and-neck clinics and could be used to trigger interventions.

  8. Beam size measurement at high radiation levels

    International Nuclear Information System (INIS)

    Decker, F.J.

    1991-05-01

    At the end of the Stanford Linear Accelerator the high energy electron and positron beams are quite small. Beam sizes below 100 μm (σ) as well as the transverse distribution, especially tails, have to be determined. Fluorescent screens observed by TV cameras provide a quick two-dimensional picture, which can be analyzed by digitization. For running the SLAC Linear Collider (SLC) with low backgrounds at the interaction point, collimators are installed at the end of the linac. This causes a high radiation level so that the nearby cameras die within two weeks and so-called ''radiation hard'' cameras within two months. Therefore an optical system has been built, which guides a 5 mm wide picture with a resolution of about 30 μm over a distance of 12 m to an accessible region. The overall resolution is limited by the screen thickness, optical diffraction and the line resolution of the camera. Vibration, chromatic effects or air fluctuations play a much less important role. The pictures are colored to get fast information about the beam current, size and tails. Beside the emittance, more information about the tail size and betatron phase is obtained by using four screens. This will help to develop tail compensation schemes to decrease the emittance growth in the linac at high currents. 4 refs., 2 figs

  9. Echo-enabled tunable terahertz radiation generation with a laser-modulated relativistic electron beam

    Directory of Open Access Journals (Sweden)

    Zhen Wang

    2014-09-01

    Full Text Available A new scheme to generate narrow-band tunable terahertz (THz radiation using a variant of the echo-enabled harmonic generation is analyzed. We show that by using an energy chirped beam, THz density modulation in the beam phase space can be produced with two lasers having the same wavelength. This removes the need for an optical parametric amplifier system to provide a wavelength-tunable laser to vary the central frequency of the THz radiation. The practical feasibility and applications of this scheme are demonstrated numerically with a start-to-end simulation using the beam parameters at the Shanghai Deep Ultraviolet Free-Electron Laser facility (SDUV. The central frequency of the density modulation can be continuously tuned by either varying the chirp of the beam or the momentum compactions of the chicanes. The influence of nonlinear rf chirp and longitudinal space charge effect have also been studied in our article. The methods to generate the THz radiation in SDUV with the new scheme and the estimation of the radiation power are also discussed briefly.

  10. Effectiveness of Cepharanthin in decreasing interruptions during radiation therapy for oral cancer

    International Nuclear Information System (INIS)

    Uchiyama, Yuka; Murakami, Shumei; Kamimoto, Naoya; Nakatani, Atsutoshi; Furukawa, Souhei

    2005-01-01

    The objectives of this study was to examine the effectiveness of Cepharanthin (Kakensyoyaku, Tokyo, Japan) at decreasing side effects during radiation therapy for oral cancer and thereby allowing the completion of radiation therapy without interruption. Two hundred fifteen patients diagnosed with oral cancers were assigned to either Cepharanthin or control groups and underwent external beam irradiation. The completion of the course of radiation therapy and the occurrence of side effects such as mucositis, dysgeusia, and xerostomia during the radiation therapy were evaluated and compared. The completion rate was 87.4% for the Cepharanthin group versus 67.0% for the control group, and the difference was statistically significant (P<0.01). Mucositis did not appear in 58 of 127 cases (45.7%) in the Cepharanthin group or in 21 of 88 cases (23.9%) in the control group. Mucositis developed in 24.6% of the Cepharanthin group and 53.7% of the control group within 2 weeks of irradiation. There were significant relationships between the use of Cepharanthin and the development and timing of mucositis (both P<0.01). Cepharanthin improved the completion of radiation therapy without interruption and reduced or delayed the development of mucositis during radiation therapy for oral cancer. (author)

  11. Measured Radiation and Background Levels During Transmission of Megawatt Electron Beams Through Millimeter Apertures

    Energy Technology Data Exchange (ETDEWEB)

    Alarcon, Ricardo [Arizona State University, Glendale, AZ (United States); Balascuta, S. [Arizona State University, Glendale, AZ (United States); Benson, Stephen V. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Bertozzi, William [Massachusetts Institute of Technology, Cambridge, MA (United States); Boyce, James R. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Cowan, Ray [Massachusetts Institute of Technology, Cambridge, MA (United States); Douglas, David R. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Evtushenko, Pavel [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Fisher, P. [Massachusetts Institute of Technology, Cambridge, MA (United States); Ihloff, Ernest E. [Hampton University, Hampton, VA (United States); Kalantarians, Narbe [Hampton University, Hampton, VA (United States); Kelleher, Aidan Michael [Massachusetts Institute of Technology, Cambridge, MA (United States); Krossler, W. J. [William and Mary College, Williamsburg, VA (United States); Legg, Robert A. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Long, Elena [University of New Hampshire, Durham, NH (United States); Milner, Richard [Massachusetts Institute of Technology, Cambridge, MA (United States); Neil, George R. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Ou, Longwu [Massachusetts Institute of Technology, Cambridge, MA (United States); Schmookler, Barack Abraham [Massachusetts Institute of Technology, Cambridge, MA (United States); Tennant, Christopher D. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Tschalar, C. [Massachusetts Institute of Technology, Cambridge, MA (United States); Williams, Gwyn P. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Zhang, Shukui [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

    2013-11-01

    We report measurements of photon and neutron radiation levels observed while transmitting a 0.43 MW electron beam through millimeter-sized apertures and during beam-off, but accelerating gradient RF-on, operation. These measurements were conducted at the Free-Electron Laser (FEL) facility of the Jefferson National Accelerator Laboratory (JLab) using a 100 MeV electron beam from an energy-recovery linear accelerator. The beam was directed successively through 6 mm, 4 mm, and 2 mm diameter apertures of length 127 mm in aluminum at a maximum current of 4.3 mA (430 kW beam power). This study was conducted to characterize radiation levels for experiments that need to operate in this environment, such as the proposed DarkLight Experiment. We find that sustained transmission of a 430 kW continuous-wave (CW) beam through a 2 mm aperture is feasible with manageable beam-related backgrounds. We also find that during beam-off, RF-on operation, multipactoring inside the niobium cavities of the accelerator cryomodules is the primary source of ambient radiation when the machine is tuned for 130 MeV operation.

  12. Mutation induction by ion beams in arabidopsis

    International Nuclear Information System (INIS)

    Tanaka, Atsushi

    1999-01-01

    An investigation was made on characteristics of ion beams for the biological effects and the induction of mutation using Arabidopsis plant as a model plant for the molecular genetics. Here, the characteristics of mutation at the molecular level as well as new mutants induced by ion beams were described. The ast and sep1 were obtained from the offspring of 1488 carbon ion-irradiated seeds respectively. The uvi1-uvi4 mutants were also induced from 1280 M 1 lines. Thus, ion beams can induce not only known mutants such as tt, gl and hy but also novel mutants with high frequency. Even in the tt phenotype, two new mutant loci other than known loci were found. In chrysanthemum, several kinds of single, complex or stripped flower-color mutants that have been never induced by γirradiation, indicating that ion beams could produce a variety of mutants with the same phenotype. In conclusion, ion beams for the mutation induction are characterized by 1) to induce mutants with high frequency, 2) to show broad mutation spectrum and 3) to produce novel mutants. For these reasons, chemical mutagens such as EMS and low LET ionizing radiation such as X-rays and γ-rays will predominantly induce many but small modifications or DNA damages on the DNA strands. As the result, several point mutations will be produced on the genome. On the contrary, ion beams as a high LET ionizing radiation will not cause so many but large and irreparable DNA damage locally, resulting in production of limited number of null mutation. (M.N.)

  13. Mutation induction by ion beams in arabidopsis

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Atsushi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    1999-07-01

    An investigation was made on characteristics of ion beams for the biological effects and the induction of mutation using Arabidopsis plant as a model plant for the molecular genetics. Here, the characteristics of mutation at the molecular level as well as new mutants induced by ion beams were described. The ast and sep1 were obtained from the offspring of 1488 carbon ion-irradiated seeds respectively. The uvi1-uvi4 mutants were also induced from 1280 M{sub 1} lines. Thus, ion beams can induce not only known mutants such as tt, gl and hy but also novel mutants with high frequency. Even in the tt phenotype, two new mutant loci other than known loci were found. In chrysanthemum, several kinds of single, complex or stripped flower-color mutants that have been never induced by {gamma}irradiation, indicating that ion beams could produce a variety of mutants with the same phenotype. In conclusion, ion beams for the mutation induction are characterized by 1) to induce mutants with high frequency, 2) to show broad mutation spectrum and 3) to produce novel mutants. For these reasons, chemical mutagens such as EMS and low LET ionizing radiation such as X-rays and {gamma}-rays will predominantly induce many but small modifications or DNA damages on the DNA strands. As the result, several point mutations will be produced on the genome. On the contrary, ion beams as a high LET ionizing radiation will not cause so many but large and irreparable DNA damage locally, resulting in production of limited number of null mutation. (M.N.)

  14. INFLUENCE OF INCUBATION TIME, GAMMA RAYS AND ELECTRON BEAM ON RADIATION RESISTANCE OF SOME SELECTED PATHOGENS

    International Nuclear Information System (INIS)

    EL-HIFNAWI, H.N.; EL-TABLAWY, S.Y.

    2009-01-01

    The effect of different growth phases on the radiation resistance, antibiotic susceptibility and pathogenicity of certain selected pathogens (Escherichia coli, Candida albicans and Staphylococcus aureus) was studied in mice. The obtained results showed that Escherichia coli was slightly more resistant to gamma radiation in 18 h than 24 h or 48 h but it was relatively more resistant to electron beam in 24 h and 48 h than 18 h. Candida albicans showed radiation resistance nearly the same in all incubation times in the case of gamma radiation while for electron beam, its radiation resistance was slightly more in 24 h and 48 h than in 18 h. On the other hand, Staphylococcus aureus recorded much more resistance to gamma radiation in the 48 h than in 24 h or 18 h whereas in the case of electron beam, it was slightly more resistant in 18 h than in 24 h and 48 h.The antibiotic susceptibility of Escherichia coli reported that the exposure to gamma radiation at 3 kGy and electron beam at 6 kGy increase the susceptibility to the nalidixic acid and nitrofurantoin. When Candida albicans was exposed to 3 kGy gamma radiation and 6 kGy electron beam, the same sensitivity to nystatin was observed in comparison with the unexposed one while the sensitivity of Staphylococcus aureus to some antibiotics (amoxicillin, nitrofurantoin and tetracycline) was decreased after exposure to gamma radiation at 0.75 and 2 kGy and electron beam at 6 kGy, but for other antibiotics (trimethoprim/ sulfamethoxazole), the sensitivity was increased at 6 kGy electron beam.The lethality percent recorded after the oral ingestion of the mice with the unexposed Escherichia coli and Candida albicans were 25% and 100%, respectively, and for 6 kGy exposure to electron beam was 0% . The cotaneous disease and abscesses caused by the intradermal injection of the mice with unexposed Staphylococcus aureus was 75% and for 6 kGy exposure to electron beam was 25%.

  15. Radiation-induced camptocormia and dropped head syndrome. Review and case report of radiation-induced movement disorders

    International Nuclear Information System (INIS)

    Seidel, Clemens; Kuhnt, Thomas; Kortmann, Rolf-Dieter; Hering, Kathrin

    2015-01-01

    In recent years, camptocormia and dropped head syndrome (DHS) have gained attention as particular forms of movement disorders. Camptocormia presents with involuntary forward flexion of the thoracolumbar spine that typically increases during walking or standing and may severely impede walking ability. DHS is characterized by weakness of the neck extensors and a consecutive inability to extend the neck; in severe cases the head is fixed in a ''chin to chest position.'' Many diseases may underlie these conditions, and there have been some reports about radiation-induced camptocormia and DHS. A PubMed search with the keywords ''camptocormia,'' ''dropped head syndrome,'' ''radiation-induced myopathy,'' ''radiation-induced neuropathy,'' and ''radiation-induced movement disorder'' was carried out to better characterize radiation-induced movement disorders and the radiation techniques involved. In addition, the case of a patient developing camptocormia 23 years after radiation therapy of a non-Hodgkin's lymphoma of the abdomen is described. In total, nine case series of radiation-induced DHS (n = 45 patients) and - including our case - three case reports (n = 3 patients) about radiogenic camptocormia were retrieved. Most cases (40/45 patients) occurred less than 15 years after radiotherapy involving extended fields for Hodgkin's disease. The use of wide radiation fields including many spinal segments with paraspinal muscles may lead to radiation-induced movement disorders. If paraspinal muscles and the thoracolumbar spine are involved, the clinical presentation can be that of camptocormia. DHS may result if there is involvement of the cervical spine. To prevent these disorders, sparing of the spine and paraspinal muscles is desirable. (orig.) [de

  16. Grading xerostomia by physicians or by patients after intensity-modulated radiotherapy of head-and-neck cancer

    International Nuclear Information System (INIS)

    Meirovitz, Amichay; Murdoch-Kinch, Carol Anne; Schipper, Mathew; Pan, Charlie; Eisbruch, Avraham

    2006-01-01

    Purpose: To assess observer-based vs. patient self-reported scoring of xerostomia after intensity-modulated radiotherapy (IMRT) of head-and-neck (HN) cancer. Methods: A total of 38 patients who had received IMRT for HN cancer underwent xerostomia evaluations 6 to 24 months after completion of therapy using three methods each time: (1) Grading by 3 observers according to the Radiotherapy Oncology Group/European Organization for Research and Therapy of Cancer (RTOG/EORTC) system; (2) patient self-reported validated xerostomia questionnaire (XQ); and (3) major salivary gland flow measurements. Results: The interobserver agreement regarding the RTOG/EORTC grades was moderate: κ-coefficient 0.54 (95% CI = 0.31-0.76). The correlations between the average RTOG/EORTC grades and the salivary flow rates were not statistically significant. A trend for significant correlation was observed between these grades and the percent (relative to the pretherapy) nonstimulated salivary flow rates (p = 0.07), but not with the percent stimulated flow rates. Better correlations were found between grading made more than the median time (15 min) after the last liquid sipping and the nonstimulated (but not the stimulated) flows compared with grading made shortly after sipping. In contrast, significant correlations were found between the XQ scores and the nonstimulated (p < 0.005) and the stimulated (p < 0.005) salivary flow rates, as well as with the percentages of the corresponding pretherapy values (p = 0.002 and 0.038, respectively). No significant correlation was found between the RTOG/EORTC grades and the XQ scores. The observer-based grades underestimated the severity of xerostomia compared with the patient self-reported scores. Conclusions: Patient self-reported, rather than physician-assessed scores, should be the main end points in evaluating xerostomia

  17. A beam radiation monitor based on CVD diamonds for SuperB

    Science.gov (United States)

    Cardarelli, R.; Di Ciaccio, A.

    2013-08-01

    Chemical Vapor Deposition (CVD) diamond particle detectors are in use in the CERN experiments at LHC and at particle accelerator laboratories in Europe, USA and Japan mainly as beam monitors. Nowadays it is considered a proven technology with a very fast signal read-out and a very high radiation tolerance suitable for measurements in high radiation environment zones i.e. near the accelerators beam pipes. The specific properties of CVD diamonds make them a prime candidate for measuring single particles as well as high-intensity particle cascades, for timing measurements on the sub-nanosecond scale and for beam protection systems in hostile environments. A single-crystalline CVD (scCVD) diamond sensor, read out with a new generation of fast and high transition frequency SiGe bipolar transistor amplifiers, has been tested for an application as radiation monitor to safeguard the silicon vertex tracker in the SuperB detector from excessive radiation damage, cumulative dose and instantaneous dose rates. Test results with 5.5 MeV alpha particles from a 241Am radioactive source and from electrons from a 90Sr radioactive source are presented in this paper.

  18. Contribution of radiation-induced, nitric oxide-mediated bystander effect to radiation-induced adaptive response.

    Science.gov (United States)

    Matsumoto, H.; Ohnishi, T.

    There has been a recent upsurge of interest in radiation-induced adaptive response and bystander effect which are specific modes in stress response to low-dose low-dose rate radiation Recently we found that the accumulation of inducible nitric oxide NO synthase iNOS in wt p53 cells was induced by chronic irradiation with gamma rays followed by acute irradiation with X-rays but not by each one resulting in an increase in nitrite concentrations of medium It is suggested that the accumulation of iNOS may be due to the depression of acute irradiation-induced p53 functions by pre-chronic irradiation In addition we found that the radiosensitivity of wt p53 cells against acute irradiation with X-rays was reduced after chronic irradiation with gamma rays This reduction of radiosensitivity of wt p53 cells was nearly completely suppressed by the addition of NO scavenger carboxy-PTIO to the medium This reduction of radiosensitivity of wt p53 cells is just radiation-induced adaptive response suggesting that NO-mediated bystander effect may considerably contribute to adaptive response induced by radiation

  19. Treating Radiation Induced Skin Injury and Fibrosis Using Small Molecule Thiol Modifying Agents

    Science.gov (United States)

    2016-10-01

    necrosis after the animals were sacrificed 1 week postop. Findings confirmed RTA-408 when delivered during radiation resulted in significant...irradiation induces extensive flap necrosis at the distal end of the skin flap 5 . In all experiments irradiation was performed using external beam...collagen deposition, vascular density, and mRNA expression of mediators of chronic inflammation and fibrosis. Figure1: A) Initial wound at

  20. Erythrocyte stiffness during morphological remodeling induced by carbon ion radiation.

    Directory of Open Access Journals (Sweden)

    Baoping Zhang

    Full Text Available The adverse effect induced by carbon ion radiation (CIR is still an unavoidable hazard to the treatment object. Thus, evaluation of its adverse effects on the body is a critical problem with respect to radiation therapy. We aimed to investigate the change between the configuration and mechanical properties of erythrocytes induced by radiation and found differences in both the configuration and the mechanical properties with involving in morphological remodeling process. Syrian hamsters were subjected to whole-body irradiation with carbon ion beams (1, 2, 4, and 6 Gy or X-rays (2, 4, 6, and 12 Gy for 3, 14 and 28 days. Erythrocytes in peripheral blood and bone marrow were collected for cytomorphological analysis. The mechanical properties of the erythrocytes were determined using atomic force microscopy, and the expression of the cytoskeletal protein spectrin-α1 was analyzed via western blotting. The results showed that dynamic changes were evident in erythrocytes exposed to different doses of carbon ion beams compared with X-rays and the control (0 Gy. The magnitude of impairment of the cell number and cellular morphology manifested the subtle variation according to the irradiation dose. In particular, the differences in the size, shape and mechanical properties of the erythrocytes were well exhibited. Furthermore, immunoblot data showed that the expression of the cytoskeletal protein spectrin-α1 was changed after irradiation, and there was a common pattern among its substantive characteristics in the irradiated group. Based on these findings, the present study concluded that CIR could induce a change in mechanical properties during morphological remodeling of erythrocytes. According to the unique characteristics of the biomechanical categories, we deduce that changes in cytomorphology and mechanical properties can be measured to evaluate the adverse effects generated by tumor radiotherapy. Additionally, for the first time, the current study

  1. Power plant by deuteron beams using indirect-driven target

    International Nuclear Information System (INIS)

    Niu, Keishiro

    1989-01-01

    An indirect-driven target is proposed to be used for 6-beam nonuniform irradiation of deuteron particles. The target consists of 5 layers; tamper, radiator, smoother (radiation gap), absorber (pusher) and solid DT fuel. The fluctuation comes from nonuniform energy deposition in the radiator layer. Through the smoother layer, radiative energy transport from the radiator layer to the absorber layer is expected to smooth out the temperature fluctuation in the absorber layer. The total beam energy of 12 MJ is launched to the target by 6 beams. In order to delete the charge of the front edge of the propagating deuteron beam, the electron beam is proposed to be launched to the target with the same velocity and with the same number density at the same time of the deuteron extraction form the diode. To stabilize the beam propagation, the electron beam has a rotation velocity which induces the magnetic field in the propagation direction. The construction of the power supply system whose total stored energy is 12 MJ seems to be not difficult and to be economical. (author)

  2. Acoustical and optical radiation pressure and the development of single beam acoustical tweezers

    International Nuclear Information System (INIS)

    Thomas, Jean-Louis; Marchiano, Régis; Baresch, Diego

    2017-01-01

    Studies on radiation pressure in acoustics and optics have enriched one another and have a long common history. Acoustic radiation pressure is used for metrology, levitation, particle trapping and actuation. However, the dexterity and selectivity of single-beam optical tweezers are still to be matched with acoustical devices. Optical tweezers can trap, move and position micron size particles, biological samples or even atoms with subnanometer accuracy in three dimensions. One limitation of optical tweezers is the weak force that can be applied without thermal damage due to optical absorption. Acoustical tweezers overcome this limitation since the radiation pressure scales as the field intensity divided by the speed of propagation of the wave. However, the feasibility of single beam acoustical tweezers was demonstrated only recently. In this paper, we propose a historical review of the strong similarities but also the specificities of acoustical and optical radiation pressures, from the expression of the force to the development of single-beam acoustical tweezers. - Highlights: • Studies on radiation pressure in acoustics and optics have enriched one another and have a long common history. • Acoustic radiation pressure is used for metrology, levitation, particle trapping and actuation. • However, the dexterity and selectivity of single-beam optical tweezers are still to be matched with acoustical devices. • Optical tweezers can trap, move and positioned micron size particles with subnanometer accuracy in three dimensions. • One limitation of optical tweezers is the weak force that can be applied without thermal damage due to optical absorption. • Acoustical tweezers overcome this limitation since the force scales as the field intensity divided by its propagation speed. • However, the feasibility of single beam acoustical tweezers was demonstrated only recently. • We propose a review of the strong similarities but also the specificities of acoustical

  3. Nonlinear thermally induced distortions of a laser beam in a cryogenic disk amplifier

    International Nuclear Information System (INIS)

    Vyatkin, A G; Khazanov, Efim A

    2009-01-01

    Taking into account the temperature dependences of the heat conductivity, the refractive index, and the thermal expansion coefficient, we calculated the temperature, elastic stresses, a thermally induced lens and depolarisation of a beam in a cryogenic disk amplifier (an Yb:YAG disk placed between a copper cylinder and a sapphire disk cooled by liquid nitrogen). When the active element (the thickness is 0.6 mm, the orientation is [001], the atomic concentration of Yb is 10%) is pumped by radiation from a diode laser (the beam diameter is 6 mm), the temperature does not exceed 140 K for the heat release power of 100 W. In this case, elastic stresses in the active element are six times lower than the maximum permissible value. The focal distance of the thermally induced lens is 5.5 m and the depolarisation rate is 0.038% per two passes through the active element. Although the heat conductivity of the active element rapidly decreases with temperature, the thermal load can be increased by 1.5-2 times when the dimensions of the active element remain constant. (active media)

  4. Radiation-induced instability of human genome

    International Nuclear Information System (INIS)

    Ryabchenko, N.N.; Demina, Eh.A.

    2014-01-01

    A brief review is dedicated to the phenomenon of radiation-induced genomic instability where the increased level of genomic changes in the offspring of irradiated cells is characteristic. Particular attention is paid to the problems of genomic instability induced by the low-dose radiation, role of the bystander effect in formation of radiation-induced instability, and its relationship with individual radiosensitivity. We believe that in accordance with the paradigm of modern radiobiology the increased human individual radiosensitivity can be formed due to the genome instability onset and is a significant risk factor for radiation-induced cancer

  5. Modelling radiation fields of ion beams in tissue-like materials

    International Nuclear Information System (INIS)

    Burigo, Lucas Norberto

    2014-01-01

    Fast nuclei are ionizing radiation which can cause deleterious effects to irradiated cells. The modelling of the interactions of such ions with matter and the related effects are very important to physics, radiobiology, medicine and space science and technology. A powerful method to study the interactions of ionizing radiation with biological systems was developed in the field of microdosimetry. Microdosimetry spectra characterize the energy deposition to objects of cellular size, i.e., a few micrometers. In the present thesis the interaction of ions with tissue-like media was investigated using the Monte Carlo model for Heavy-Ion Therapy (MCHIT) developed at the Frankfurt Institute for Advanced Studies. MCHIT is a Geant4-based application intended to benchmark the physical models of Geant4 and investigate the physical properties of therapeutic ion beams. We have implemented new features in MCHIT in order to calculate microdosimetric quantities characterizing the radiation fields of accelerated nucleons and nuclei. The results of our Monte Carlo simulations were compared with recent experimental microdosimetry data. In addition to microdosimetry calculations with MCHIT, we also investigated the biological properties of ion beams, e.g. their relative biological effectiveness (RBE), by means of the modified Microdosimetric-Kinetic model (MKM). The MKM uses microdosimetry spectra in describing cell response to radiation. MCHIT+MKM allowed us to study the physical and biological properties of ion beams. The main results of the thesis are as follows: MCHIT is able to describe the spatial distribution of the physical dose in tissue-like media and microdosimetry spectra for ions with energies relevant to space research and ion-beam cancer therapy; MCHIT+MKM predicts a reduction of the biological effectiveness of ions propagating in extended medium due to nuclear fragmentation reactions; We predicted favourable biological dose-depth profiles for monoenergetic helium and

  6. Aerosol nucleation induced by a high energy particle beam

    DEFF Research Database (Denmark)

    Enghoff, Martin Andreas Bødker; Pedersen, Jens Olaf Pepke; Uggerhøj, Ulrik I.

    2011-01-01

    We have studied sulfuric acid aerosol nucleation in an atmospheric pressure reaction chamber using a 580 MeV electron beam to ionize the volume of the reaction chamber. We find a clear contribution from ion-induced nucleation and consider this to be the first unambiguous observation of the ion......-effect on aerosol nucleation using a particle beam under conditions that resemble the Earth's atmosphere. By comparison with ionization using a gamma source we further show that the nature of the ionizing particles is not important for the ion-induced component of the nucleation. This implies that inexpensive...... ionization sources - as opposed to expensive accelerator beams - can be used for investigations of ion-induced nucleation....

  7. Radioprotective effect of Tamarindus indica pod extract in Swiss albino mice exposed to whole body electron beam radiation

    International Nuclear Information System (INIS)

    Nandini, S.; Suchetha Kumari, N.; Ganesh Sanjeev; D'sa, Prima

    2013-01-01

    The objective of the study was to investigate the radioprotective effect of Tamarindus indica pod extract against radiation induced damage.The effect of 100 mg of hydroalcoholic extract of Tamarindus indica pod was studied in Swiss albino mice exposed to 6 Gy whole body electron beam radiation. Treatment of mice with extract for 15 days before irradiation reduced the symptoms of radiation sickness when compared with the untreated irradiated group. The irradiated animals showed an elevation in lipid peroxidation and reduction in glutathione, total antioxidants and antioxidant enzymes such as glutathione peroxidase and catalase activities. Radiation induced mice has shown micronucleus in the bone marrow cells. Treatment of mice with Tamarindus indica pod extract before irradiation caused a significant reduction in lipid peroxidation followed by significant elevation in reduced glutathione, total antioxidants, glutathione peroxidase and catalase activity. It also showed a reduction in the micronucleus formation in bone marrow cells. Results indicate that the radioprotective activity of Tamarindus indica pod extract may be due to free radical scavenging attributed as a result of increased antioxidant level in mice. (author)

  8. Testing beam-induced quench levels of LHC superconducting magnets

    CERN Document Server

    Auchmann, B.; Bednarek, M.; Bellodi, G.; Bracco, C.; Bruce, R.; Cerutti, F.; Chetvertkova, V.; Dehning, B.; Granieri, P.P.; Hofle, W.; Holzer, E.B.; Lechner, A.; Del Busto, E. Nebot; Priebe, A.; Redaelli, S.; Salvachua, B.; Sapinski, M.; Schmidt, R.; Shetty, N.; Skordis, E.; Solfaroli, M.; Steckert, J.; Valuch, D.; Verweij, A.; Wenninger, J.; Wollmann, D.; Zerlauth, M.

    2015-06-25

    In the years 2009-2013 the Large Hadron Collider (LHC) has been operated with the top beam energies of 3.5 TeV and 4 TeV per proton (from 2012) instead of the nominal 7 TeV. The currents in the superconducting magnets were reduced accordingly. To date only seventeen beam-induced quenches have occurred; eight of them during specially designed quench tests, the others during injection. There has not been a single beam- induced quench during normal collider operation with stored beam. The conditions, however, are expected to become much more challenging after the long LHC shutdown. The magnets will be operating at near nominal currents, and in the presence of high energy and high intensity beams with a stored energy of up to 362 MJ per beam. In this paper we summarize our efforts to understand the quench levels of LHC superconducting magnets. We describe beam-loss events and dedicated experiments with beam, as well as the simulation methods used to reproduce the observable signals. The simulated energy depositio...

  9. High-power beam-based coherently enhanced THz radiation source

    Directory of Open Access Journals (Sweden)

    Yuelin Li (李跃林

    2008-08-01

    Full Text Available We propose a compact Smith-Purcell radiation device that can potentially generate high average power THz radiation with high conversion efficiency. The source is based on a train of short electron bunches from an rf photoemission gun at an energy of a few MeV. Particle tracking simulation and analysis show that, with a beam current of 1 mA, it is feasible to generate hundreds of watts of narrow-band THz radiation at a repetition rate of 1 MHz.

  10. LIPAc personnel protection system for realizing radiation licensing conditions on injector commissioning with deuteron beam

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Hiroki, E-mail: takahashi.hiroki@jaea.go.jp [IFMIF/EVEDA Accelerator Group, Japan Atomic Energy Agency (JAEA), Rokkasho, Aomori (Japan); Narita, Takahiro; Kasugai, Atsushi [IFMIF/EVEDA Accelerator Group, Japan Atomic Energy Agency (JAEA), Rokkasho, Aomori (Japan); Kojima, Toshiyuki [Gitec Co. Ltd., Hachinohe, Aomori (Japan); Marqueta, Alvaro; Nishiyama, Koichi [IFMIF/EVEDA Project Team, Rokkasho, Aomori (Japan); Sakaki, Hironao [Quantum Beam Science Center, JAEA, Kizu, Kyoto (Japan); Gobin, Raphael [Commissariat à l’Energie Atomique et aux Energies Alternatives, CEA/Saclay, DSM/IRFU, Gif/Yvette (France)

    2016-11-01

    Highlights: • Personnel Protection System (PPS) is developed to adapt the radiation licensing. • PPS achieves the target performance to secure the personnel safety. • Pulse Duty Management System (PDMS) is developed to manage the beam-operation-time. • Satisfying performance of PDMS is confirmed by injector operation with H+ beam. • By the result of PPS and PDMS tests, the radiation license was successfully obtained. - Abstract: The performance validation of the Linear IFMIF Prototype Accelerator (LIPAc), up to the energy of 9 MeV deuteron beam with 125 mA continuous wave (CW), is planned in Rokkasho, Japan. There are three main phases of LIPAc performance validation: Injector commissioning, RFQ commissioning and LIPAc commissioning. Injector commissioning was started by H{sup +} and D{sup +} beam. To apply the radiation licensing for the Injector commissioning, the entering/leaving to/from accelerator vault should be under control, and access to the accelerator vault has to be prohibited for any person during the beam operation. The Personnel Protection System (PPS) was developed to adapt the radiation licensing conditions. The licensing requests that PPS must manage the accumulated D{sup +} current. So, to manage the overall D{sup +} beam time during injector operation, Pulse Duty Management System (PDMS) was developed as a configurable subsystem as part of the PPS. The PDMS was tested during H{sup +} beam (as simulated D{sup +}) operation, to confirm that it can handle the beam inhibit from Injector before the beam accumulation is above the threshold value specified in the radiation licensing condition. In this paper, the design and configuration of these systems and the result of the tests are presented.

  11. Laser-Driven Very High Energy Electron/Photon Beam Radiation Therapy in Conjunction with a Robotic System

    Directory of Open Access Journals (Sweden)

    Kazuhisa Nakajima

    2014-12-01

    Full Text Available We present a new external-beam radiation therapy system using very-high-energy (VHE electron/photon beams generated by a centimeter-scale laser plasma accelerator built in a robotic system. Most types of external-beam radiation therapy are delivered using a machine called a medical linear accelerator driven by radio frequency (RF power amplifiers, producing electron beams with an energy range of 6–20 MeV, in conjunction with modern radiation therapy technologies for effective shaping of three-dimensional dose distributions and spatially accurate dose delivery with imaging verification. However, the limited penetration depth and low quality of the transverse penumbra at such electron beams delivered from the present RF linear accelerators prevent the implementation of advanced modalities in current cancer treatments. These drawbacks can be overcome if the electron energy is increased to above 50 MeV. To overcome the disadvantages of the present RF-based medical accelerators, harnessing recent advancement of laser-driven plasma accelerators capable of producing 1-GeV electron beams in a 1-cm gas cell, we propose a new embodiment of the external-beam radiation therapy robotic system delivering very high-energy electron/photon beams with an energy of 50–250 MeV; it is more compact, less expensive, and has a simpler operation and higher performance in comparison with the current radiation therapy system.

  12. Evaluation of the efficacy of a topical sialogogue spray containing malic acid 1% in elderly people with xerostomia: a double-blind, randomized clinical trial.

    Science.gov (United States)

    Gómez-Moreno, Gerardo; Cabrera-Ayala, Maribel; Aguilar-Salvatierra, Antonio; Guardia, Javier; Ramírez-Fernández, María Piedad; González-Jaranay, Maximino; Calvo-Guirado, José Luis

    2014-12-01

    The aim of this study was to evaluate the clinical efficacy of a topical sialogogue spray containing 1% malic acid for elderly people affected by xerostomia. This research took the form of a double-blind, randomized clinical trial. Forty-one individuals (mean age: 78.7 years) with xerostomia were divided into two groups: for the first 'intervention group' (21 subjects) a topical sialogogue spray (1% malic acid) was applied, while for the second 'control group' (20 subjects), a placebo spray was applied; for both groups, the sprays were applied on demand during 2 weeks. The Xerostomia Inventory (XI) was used to evaluate xerostomia levels before and after product/placebo application. Unstimulated and stimulated salivary flows rates, before and after spray application, were measured. XI scores decreased significantly (clinically meaningful) from 36.4 ± 7.3 points to 29.1 ± 7.1 (p xerostomia in an elderly population and increased unstimulated and stimulated salivary flows rates. © 2013 The Gerodontology Society and John Wiley & Sons A/S.

  13. Responses of diode detectors to radiation beams from teletherapy machines

    International Nuclear Information System (INIS)

    Malinda, Lora; Nasukha

    2003-01-01

    Responses of diode detectors to radiation beams from teletherapy machines. It has been carried out responses to two sets of diode detector by using the beams of teletherapy Co-60 and medical linear accelerator. Each set of consist of 8 diode detectors was irradiated by using gamma beams from teletherapy Co-60 machines and 6 MV and 10 MV foron beams from medical linear accelerator and 6.9.12.16. and 20 MeV electron beams from medical linear accelerator. The detectors were positioned on the phantom circularly and radially and electronic equilibrium condition for all type and energy beams. It was found that every detectors had own individual response and it is not to be uniformity, since the fluctuation in between 16.6 % to 30.9 %. All detectors responses are linear to gamma and foron beams, and also for energy above 6 MeV for electron beams. Nonlinearity response occurs for 6 MeV electron beam, it is probably from the assumption of electronic equilibrium

  14. Scattered radiation from applicators in clinical electron beams.

    NARCIS (Netherlands)

    Battum, L.J. van; Zee, W. van der; Huizenga, H.

    2003-01-01

    In radiotherapy with high-energy (4-25 MeV) electron beams, scattered radiation from the electron applicator influences the dose distribution in the patient. In most currently available treatment planning systems for radiotherapy this component is not explicitly included and handled only by a slight

  15. Image-guided small animal radiation research platform: calibration of treatment beam alignment

    International Nuclear Information System (INIS)

    Matinfar, Mohammad; Iordachita, Iulian; Kazanzides, Peter; Ford, Eric; Wong, John

    2009-01-01

    Small animal research allows detailed study of biological processes, disease progression and response to therapy with the potential to provide a natural bridge to the clinical environment. The small animal radiation research platform (SARRP) is a portable system for precision irradiation with beam sizes down to approximately 0.5 mm and optimally planned radiation with on-board cone-beam CT (CBCT) guidance. This paper focuses on the geometric calibration of the system for high-precision irradiation. A novel technique for the calibration of the treatment beam is presented, which employs an x-ray camera whose precise positioning need not be known. Using the camera system we acquired a digitally reconstructed 3D 'star shot' for gantry calibration and then developed a technique to align each beam to a common isocenter with the robotic animal positioning stages. The calibration incorporates localization by cone-beam CT guidance. Uncorrected offsets of the beams with respect to the calibration origin ranged from 0.4 mm to 5.2 mm. With corrections, these alignment errors can be reduced to the sub-millimeter range. The calibration technique was used to deliver a stereotactic-like arc treatment to a phantom constructed with EBT Gafchromic films. All beams were shown to intersect at a common isocenter with a measured beam (FWHM) of approximately 1.07 mm using the 0.5 mm collimated beam. The desired positioning accuracy of the SARRP is 0.25 mm and the results indicate an accuracy of 0.2 mm. To fully realize the radiation localization capabilities of the SARRP, precise geometric calibration is required, as with any such system. The x-ray camera-based technique presented here provides a straightforward and semi-automatic method for system calibration.

  16. Liposomal treatment of xerostomia, odor, and taste abnormalities in patients with head and neck cancer.

    Science.gov (United States)

    Heiser, Clemens; Hofauer, Benedikt; Scherer, Elias; Schukraft, Johannes; Knopf, Andreas

    2016-04-01

    Smell and taste disorders, sicca symptoms, can be detected in patients with head and neck cancer. The purpose of this study was to assess the utility of local liposomal application in the treatment of patients with head and neck cancers. Ninety-eight patients with head and neck cancer were included in this study. The groups were defined as: group 1 = only surgery; group 2 = surgery + adjuvant radiochemotherapy; and group 3 = primarily radiochemotherapy. All patients had finished cancer treatment and received liposomal sprays for the nose and mouth for 2 months (LipoNasal, LipoSaliva; Optima Pharmaceutical GmbH, Germany) and suffered from taste and smell disorders. We performed tests with "Sniffin' Sticks," "Taste Strips," and a xerostomia questionnaire before and after treatment. After application of liposomes, patients demonstrated a statistically significant increase in smell and taste, and reduced xerostomia. Our results demonstrate that using nonpharmaceutical liposomal sprays improve smell, taste, and symptoms of xerostomia in patients with head and neck cancer. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1232-E1237, 2016. © 2015 Wiley Periodicals, Inc.

  17. Detection of coherent X-ray transition radiation and its application to beam diagnostics

    International Nuclear Information System (INIS)

    Piestrup, M.A.; Boyers, D.G.; Pincus, C.I.; Li Qiang; Moran, M.J.; Bergstrom, J.C.; Caplan, H.S.; Silzer, R.M.; Skopik, D.M.; Rothbart, G.B.

    1989-01-01

    We investigate the use of coherent X-ray transition radiation to measure the energy of ultra-relativistic charged particles. This can be used for beam diagnostics for both high-repetition-rate and single-pulse, high-current accelerators. The research also has possible applications for the detection and identification of these particles. By selecting foil thickness and spacing, it is possible to design radiators whose angle of emission varies radically over a range of charged particle energies. We have constructed three coherent radiators and tested them at two accelerators using electron beam energies ranging from 50 to 228 MeV. Soft X-ray emission (1-3 keV) was emitted in a circularly symmetrical annulus with half-angle divergence of 2.5-9.0 mrad. The angle of peak emission was found to increase with electron-beam energy, in contrast to the incoherent case for which the angle of emission varies inversely with electron-beam energy. (orig.)

  18. Measurement of NdFeB permanent magnets demagnetization induced by high energy electron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Temnykh, Alexander B. [Wilson Lab, Cornell University, LEPP, Ithaca, NY 14850 (United States)], E-mail: abt6@cornell.edu

    2008-03-11

    Demagnetization of NdFeB permanent magnets has been measured as function of radiation dose induced by high energy electrons. The magnet samples were of different intrinsic coercive forces, {approx_equal}12 and {approx_equal}20KOe, dimensions and direction of magnetization. 5 GeV electron beam from 12 GeV Cornell Synchrotron was used as a radiation source. A calorimetric technique was employed for radiation dose measurement. Results indicated that depending on the sample intrinsic coercive force, shape and direction of magnetization the radiation dose causing 1% of demagnetization of the sample varies from 0.0765{+-}0.005Mrad to 11.3{+-}3.0Mrad, i.e., by more than a factor of 100. Experimental data analysis revealed that demagnetization of the given sample induced by radiation is strongly correlated with the sample demagnetizing temperature. This correlation was approximated by an exponential function with two parameters obtained from the data fitting. The function can be used to predict the critical radiation dose for permanent magnet assemblies like undulator magnets based on its demagnetizing temperature. The latter (demagnetization temperature) can be determined at the design stage from 3-D magnetic modeling and permanent magnet material properties.

  19. Impact of the Wiggler Coherent Synchrotron Radiation Impedance on the Beam Instability

    International Nuclear Information System (INIS)

    Wu, Juhao

    2003-01-01

    Coherent Synchrotron Radiation (CSR) can play an important role by not only increasing the energy spread and emittance of a beam, but also leading to a potential instability. Previous studies of the CSR induced longitudinal instability were carried out for the CSR impedance due to dipole magnets. However, many storage rings include long wigglers where a large fraction of the synchrotron radiation is emitted. This includes high-luminosity factories such as DAPHNE, PEP-II, KEK-B, and CESR-C as well as the damping rings of future linear colliders. In this paper, the instability due to the CSR impedance from a wiggler is studied assuming a large wiggler parameter K. The primary consideration is a low frequency microwave-like instability, which arises near the pipe cut-off frequency. Detailed results are presented on the growth rate and threshold for the damping rings of several linear collider designs. Finally, the optimization of the relative fraction of damping due to the wiggler systems is discussed for the damping rings

  20. Managing xerostomia and salivary gland hypofunction: executive summary of a report from the American Dental Association Council on Scientific Affairs.

    Science.gov (United States)

    Plemons, Jacqueline M; Al-Hashimi, Ibtisam; Marek, Cindy L

    2014-08-01

    Xerostomia, also known as "dry mouth," is a common but frequently overlooked condition that is typically associated with salivary gland hypofunction, which is the objective measurement of reduced salivary flow. Patients with dry mouth exhibit symptoms of variable severity that are commonly attributed to medication use, chronic disease and medical treatment, such as radiotherapy to the head and neck region. Chronic xerostomia significantly increases the risk of experiencing dental caries, demineralization, tooth sensitivity, candidiasis and other oral diseases that may affect quality of life negatively. This article presents a multidisciplinary approach to the clinical management of xerostomia, consistent with the findings of published systematic reviews on this key clinical issue. Initial evaluation of patients with dry mouth should include a detailed health history to facilitate early detection and identify underlying causes. Comprehensive evaluation, diagnostic testing and periodic assessment of salivary flow, followed by corrective actions, may help prevent significant oral disease. A systematic approach to xerostomia management can facilitate interdisciplinary patient care, including collaboration with physicians regarding systemic conditions and medication use. Comprehensive management of xerostomia and hyposalivation should emphasize patient education and lifestyle modifications. It also should focus on various palliative and preventive measures, including pharmacological treatment with salivary stimulants, topical fluoride interventions and the use of sugar-free chewing gum to relieve dry-mouth symptoms and improve the patient's quality of life.

  1. Lack of Prophylactic Effects of Aloe Vera Gel on Radiation Induced Dermatitis in Breast Cancer Patients

    OpenAIRE

    Ahmadloo, Niloofar; Kadkhodaei, Behnam; Omidvari, Shapour; Mosalaei, Ahmad; Ansari, Mansour; Nasrollahi, Hamid; Hamedi, Sayed Hasan; Mohammadianpanah, Mohammad

    2017-01-01

    Purpose: Radiotherapy induced dermatitis is a common and sometimes serious side effect. We conducted a randomized study to understand whether the adjunctive use of aloe vera gel might reduce the prevalence and/or severity of radiotherapy induced dermatitis. Methods: One hundred patients with newly diagnosed breast cancer were randomized to receive aloe vera gel or nothing during adjuvant radiotherapy consisting of conventional external beam radiation using 6 MV mega voltage linear accelerator...

  2. Radiation degradation of marine polysaccharides by low energy electron beam

    International Nuclear Information System (INIS)

    Yoshii, Fumio; Nagasawa, Naotsugu; Kume, Tamikazu

    2003-01-01

    The radiation degradations of marine polysaccharides by both gamma Co-60 and electron beam irradiations are investigated. Polysaccharides and oligosaccharides can be produced by degradation of corresponding polysaccharides including marine polysaccharides such as alginates, chitin chitosan and carrageenan. The viscosity of alginate, chitosan and carrageenan solution decreases markedly with increase of the low energy electron beam irradiation time and the beam current. Furthermore, the viscosity is reduced sharply in short time for polysaccharide solution with low concentration, for instance carrageenan solution of 1%. (author)

  3. Solving radiation problems at particle accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Nikolai V. Mokhov

    2001-12-11

    At high-intensity high-energy particle accelerators, consequences of a beam-induced radiation impact on machine and detector components, people, environment and complex performance can range from negligible to severe. The specifics, general approach and tools used at such machines for radiation analysis are described. In particular, the world leader Fermilab accelerator complex is considered, with its fixed target and collider experiments, as well as new challenging projects such as LHC, VLHC, muon collider and neutrino factory. The emphasis is on mitigation of deleterious beam-induced radiation effects and on the key role of effective computer simulations.

  4. Solving radiation problems at particle accelerators

    International Nuclear Information System (INIS)

    Mokhov, N.V.

    2001-01-01

    At high-intensity high-energy particle accelerators, consequences of a beam-induced radiation impact on machine and detector components, people, environment and complex performance can range from negligible to severe. The specifics, general approach and tools used at such machines for radiation analysis are described. In particular, the world leader Fermilab accelerator complex is considered, with its fixed target and collider experiments, as well as new challenging projects such as LHC, VLHC, muon collider and neutrino factory. The emphasis is on mitigation of deleterious beam-induced radiation effects and on the key role of effective computer simulations

  5. Translation and validation of a Spanish version of the xerostomia inventory.

    Science.gov (United States)

    Serrano, Carlos; Fariña, María P; Pérez, Cristhian; Fernández, Marcos; Forman, Katherine; Carrasco, Mauricio

    2016-12-01

    The aim of this study was to validate a Spanish cross-cultural adaptation of the xerostomia inventory (XI). The original English version of XI was translated into Spanish, cross-culturally adapted and field tested. The Spanish version of XI (XI-Sp) was tested with a sample of 41 patients with xerostomia. The reliability of the XI-Sp was determined through internal consistency and test-retest methods. The construct validity of XI-Sp was determined by means of correlation between XI-Sp scores and salivary flow measurements. Overall XI-Sp scores were 40.8 (SD = 10) for the first application and 40.2 (SD = 9.5) for the second. Cronbach's alpha value for the XI-Sp was 0.89 and 0.87, respectively, while interitem correlation averages were r = 0.44 and r = 0.39 for each application. Interitem correlation and corrected total was r c ≥0.30. The test-retest intraclass correlation coefficient value for the XI-Sp score was 0.59 and 0.91. Convergent validity for construct validity correlation with salivary flow showed a medium effect size (r 2  = 0.10) for the first application but did not make a statistically significant prediction for the second (r 2  = 0.7). This study provides evidence concerning the reliability of the XI-Sp, showing that it may be a useful tool for Spanish-speaking xerostomia patients for both clinical and epidemiologic research. © 2015 John Wiley & Sons A/S and The Gerodontology Association. Published by John Wiley & Sons Ltd.

  6. Prevalence of xerostomia and the salivary flow rate in diabetic patients.

    Science.gov (United States)

    Malicka, Barbara; Kaczmarek, Urszula; Skośkiewicz-Malinowska, Katarzyna

    2014-01-01

    Diabetes is a metabolic disease characterized by hyperglycemia, which results from relative or absolute insulin deficiency. One of the first oral symptoms of diabetes is xerostomia. The aim of the study was to determine the prevalence of the xerostomia symptoms and salivary flow rate in diabetic patients according to the type of diabetes, the level of metabolic control and the duration of the disease. The study involved 156 adult patients of both sexes including 34 patients with diabetes type 1 (group C1), 59 with diabetes type 2 (group C2), and 63 generally healthy individuals as two control groups, sex- and age-matched to the diabetic group. The patients suffering from both types of diabetes were additionally subdivided according to the level of metabolic control and the duration of the disease. Xerostomia was diagnosed with the use of a specially prepared questionnaire and Fox's test. Moreover, the salivary flow rate of resting mixed saliva was measured. In type 1 diabetics, a significantly lower salivary flow rate in comparison to the age-matched control group (0.38 ± 0.19 mL/min vs. 0.53 ± 0.20 mL/min, p diabetics, a slight lower salivary flow rate was noticed (on average, 20% lower). Dry mouth was far more frequently diagnosed in type 1 diabetics than in the control group. In type 1 diabetics, in comparison to healthy subjects, a significantly lower resting flow rate of saliva and significantly higher prevalence of xerosomia were observed, but in type 2 diabetics, only a trend of such variability was observed.

  7. Characterization of a Cs-137 radiation beam for dosimeter calibrations in the CRCN-CO

    International Nuclear Information System (INIS)

    Baptista Neto, Annibal T.; Soares, Carlos M. de A.; Silva, Teogenes A. da; Correa, Rosangela da S.

    2009-01-01

    The Centro Regional de Ciencias Nucleares do Centro Oeste (CRCN-CO) has played an important role in the environmental radiation monitoring program in Goiania city. The reduce its dependence of others monitoring laboratories, the CRCN-CO acquired a model 28 JL Shepherd and Associates irradiation system with a 137 Cs source for calibrations and frequent quality control checks of radiation dosimeters. A characterization of the irradiation system was carried out with the reference standard dosimeters that are maintained by the Centro de Desenvolvimento da Tecnologia Nuclear (CDTN). The laboratory surrounding areas were monitored to demonstrate the adequate radiation protection conditions and parameters as the radiation field size, beam uniformity and the level of the scatter radiation were investigated. Dosimetry of the 137 Cs radiation beam in terms of air kerma rate was carried out at many source-detector distances with 4 (four) different beam lead attenuators. Results demonstrated that in spite of the radiation shutter automation is strongly recommended, the irradiation system is adequate and it complies with the requirements to be used for dosimeter irradiations and calibrations for the purpose of radiation protection. (author)

  8. Tolerance doses of cutaneous and mucosal tissues in ring-necked parakeets (Psittacula krameri) for external beam megavoltage radiation.

    Science.gov (United States)

    Barron, Heather W; Roberts, Royce E; Latimer, Kenneth S; Hernandez-Divers, Stephen; Northrup, Nicole C

    2009-03-01

    Currently used dosages for external-beam megavoltage radiation therapy in birds have been extrapolated from mammalian patients and often appear to provide inadequate doses of radiation for effective tumor control. To determine the tolerance doses of cutaneous and mucosal tissues of normal birds in order to provide more effective radiation treatment for tumors that have been shown to be radiation responsive in other species, ingluvial mucosa and the skin over the ingluvies of 9 ring-necked parakeets (Psittacula krameri) were irradiated in 4-Gy fractions to a total dose of either 48, 60, or 72 Gy using an isocentric cobalt-60 teletherapy unit. Minimal radiation-induced epidermal changes were present in the high-dose group histologically. Neither dose-related acute nor chronic radiation effects could be detected in any group grossly in cutaneous or mucosal tissue over a 9-month period. Radiation doses of 72 Gy in 4-Gy fractions were well tolerated in the small number of ring-necked parakeets in this initial tolerance dose study.

  9. Radiation-induced heart injury

    International Nuclear Information System (INIS)

    Suzuki, Yoshihiko; Niibe, Hideo

    1975-01-01

    In order to identify radiation-induced heart injury and to differentiate it from heart disease, an attempt was made to clarify post-irradiation heart injury by investigating the histological changes which occur during the internal between the irradiation and the time of demonstrable histological changes. A study was made of 83 autopsies in which most of the primary neoplasms were breast cancers, lung cancers and mediastinal tumors. In 43 of these autopsies the heart had been irradiated. Sixty eight dd-strain mice were also used for microautoradiographic study. Histological changes in the heart were observed in 27 of the 43 cases receiving irradiation. The limit of the tolerance dose to the heart for indicating histological changes was 1220 ret in humans. The latent period without histological changes was 2.7 months after initiation of radiation therapy. Greater heart injury was observed after re-irradiation or after the combined therapy of radiation and chemotherapy especially mitomycin (MMC). The histological findings after treatment with MMC were similar to those of radiation-induced heart injury. Results of the study indicate that the damage is secondary to radiation-induced changes of the vascula connective tissue. (Evans, G.)

  10. Testing beam-induced quench levels of LHC superconducting magnets

    Directory of Open Access Journals (Sweden)

    B. Auchmann

    2015-06-01

    Full Text Available In the years 2009–2013 the Large Hadron Collider (LHC has been operated with the top beam energies of 3.5 and 4 TeV per proton (from 2012 instead of the nominal 7 TeV. The currents in the superconducting magnets were reduced accordingly. To date only seventeen beam-induced quenches have occurred; eight of them during specially designed quench tests, the others during injection. There has not been a single beam-induced quench during normal collider operation with stored beam. The conditions, however, are expected to become much more challenging after the long LHC shutdown. The magnets will be operating at near nominal currents, and in the presence of high energy and high intensity beams with a stored energy of up to 362 MJ per beam. In this paper we summarize our efforts to understand the quench levels of LHC superconducting magnets. We describe beam-loss events and dedicated experiments with beam, as well as the simulation methods used to reproduce the observable signals. The simulated energy deposition in the coils is compared to the quench levels predicted by electrothermal models, thus allowing one to validate and improve the models which are used to set beam-dump thresholds on beam-loss monitors for run 2.

  11. Testing beam-induced quench levels of LHC superconducting magnets

    Science.gov (United States)

    Auchmann, B.; Baer, T.; Bednarek, M.; Bellodi, G.; Bracco, C.; Bruce, R.; Cerutti, F.; Chetvertkova, V.; Dehning, B.; Granieri, P. P.; Hofle, W.; Holzer, E. B.; Lechner, A.; Nebot Del Busto, E.; Priebe, A.; Redaelli, S.; Salvachua, B.; Sapinski, M.; Schmidt, R.; Shetty, N.; Skordis, E.; Solfaroli, M.; Steckert, J.; Valuch, D.; Verweij, A.; Wenninger, J.; Wollmann, D.; Zerlauth, M.

    2015-06-01

    In the years 2009-2013 the Large Hadron Collider (LHC) has been operated with the top beam energies of 3.5 and 4 TeV per proton (from 2012) instead of the nominal 7 TeV. The currents in the superconducting magnets were reduced accordingly. To date only seventeen beam-induced quenches have occurred; eight of them during specially designed quench tests, the others during injection. There has not been a single beam-induced quench during normal collider operation with stored beam. The conditions, however, are expected to become much more challenging after the long LHC shutdown. The magnets will be operating at near nominal currents, and in the presence of high energy and high intensity beams with a stored energy of up to 362 MJ per beam. In this paper we summarize our efforts to understand the quench levels of LHC superconducting magnets. We describe beam-loss events and dedicated experiments with beam, as well as the simulation methods used to reproduce the observable signals. The simulated energy deposition in the coils is compared to the quench levels predicted by electrothermal models, thus allowing one to validate and improve the models which are used to set beam-dump thresholds on beam-loss monitors for run 2.

  12. POWER BEAMING LEAKAGE RADIATION AS A SETI OBSERVABLE

    Energy Technology Data Exchange (ETDEWEB)

    Benford, James N. [Microwave Sciences, 1041 Los Arabis Lane, Lafayette, CA 94549 (United States); Benford, Dominic J., E-mail: jimbenford@gmail.com [NASA’s Goddard Space Flight Center, Observational Cosmology Laboratory, Greenbelt, MD 20771 (United States)

    2016-07-10

    The most observable leakage radiation from an advanced civilization may well be from the use of power beaming to transfer energy and accelerate spacecraft. Applications suggested for power beaming involve launching spacecraft to orbit, raising satellites to a higher orbit, and interplanetary concepts involving space-to-space transfers of cargo or passengers. We also quantify beam-driven launch to the outer solar system, interstellar precursors, and ultimately starships. We estimate the principal observable parameters of power beaming leakage. Extraterrestrial civilizations would know their power beams could be observed, and so could put a message on the power beam and broadcast it for our receipt at little additional energy or cost. By observing leakage from power beams we may find a message embedded on the beam. Recent observations of the anomalous star KIC 8462852 by the Allen Telescope Array (ATA) set some limits on extraterrestrial power beaming in that system. We show that most power beaming applications commensurate with those suggested for our solar system would be detectable if using the frequency range monitored by the ATA, and so the lack of detection is a meaningful, if modest, constraint on extraterrestrial power beaming in that system. Until more extensive observations are made, the limited observation time and frequency coverage are not sufficiently broad in frequency and duration to produce firm conclusions. Such beams would be visible over large interstellar distances. This implies a new approach to the SETI search: instead of focusing on narrowband beacon transmissions generated by another civilization, look for more powerful beams with much wider bandwidth. This requires a new approach for their discovery by telescopes on Earth. Further studies of power beaming applications should be performed, potentially broadening the parameter space of the observable features that we have discussed here.

  13. Underling modification in ion beam induced Si wafers

    International Nuclear Information System (INIS)

    Hazra, S.; Chini, T.K.; Sanyal, M.K.; Grenzer, J.; Pietsch, U.

    2005-01-01

    Subsurface (amorphous-crystalline interface) structure of keV ion beam modified Si(001) wafers was studied for the first time using non-destructive technique and compared with that of the top one. Ion-beam modifications of the Si samples were done using state-of-art high-current ion implanter facility at Saha Institute of Nuclear Physics by changing energy, dose and angle of incidence of the Ar + ion beam. To bring out the underlying modification depth-resolved x-ray grazing incidence diffraction has been carried out using synchrotron radiation facility, while the structure of the top surface was studied through atomic force microscopy

  14. Amelioration of radiation stress by antioxidants and prooxidants: role of redox transcription factors

    International Nuclear Information System (INIS)

    Sandur, Santosh Kumar

    2011-01-01

    The development of radiation countermeasures has emerged as a major area of research in radiation biology as ionizing radiation is finding wide applications in power generation, agriculture, food processing, disease diagnosis and therapy. Chemical agents used to alter tissue toxicity of radiation can be broadly divided into three categories based on the time of intervention in relation to radiation. These are: radioprotectors, mitigators, and therapeutic agents. Radiation causes injury to normal tissue by a dynamic process involving generation of reactive oxygen species (ROS), their interactions with bio-molecules, intracellular signaling, cell-to-cell communication, inflammatory responses, tissue repair and cell death. Most of the radiation-induced damage to bio-molecules is caused by the formation of free radicals resulting from the radiolysis of water. However, antioxidants that neutralize free radicals failed to reach clinic. At present, no agent, approved by the U.S. Food and Drug Administration, is available for the treatment of acute radiation syndrome (ARS), although amifostine is approved for prophylaxis of dry mouth (xerostomia) from radiotherapy of head and neck cancers. Therefore, researchers are employing new approaches to ameliorate radiation induced injury. Some of these include use of cytokines, NF-κB (Nuclear factor κB) activators, agents that induce G1 arrest, antibiotics and inhibitors of P53. We have used pro-oxidants to upregulate cytoprotective pathways as a novel strategy to protect against radiation induced hematopoietic syndrome. Different prooxidants including hydrogen peroxide, diethylmaleate, t-butylhydroperoxide and naphthoquinone and its derivatives protected lymphocytes against radiation induced cell death. Further studies were carried out with 1,4-naphthoquinone (NQ) to explore the molecular mechanism of the observed protection. Thiol containing antioxidants abrogated NQ mediated radioprotection in lymphocytes. Addition of NQ to

  15. Acoustical and optical radiation pressure and the development of single beam acoustical tweezers

    Science.gov (United States)

    Thomas, Jean-Louis; Marchiano, Régis; Baresch, Diego

    2017-07-01

    Studies on radiation pressure in acoustics and optics have enriched one another and have a long common history. Acoustic radiation pressure is used for metrology, levitation, particle trapping and actuation. However, the dexterity and selectivity of single-beam optical tweezers are still to be matched with acoustical devices. Optical tweezers can trap, move and position micron size particles, biological samples or even atoms with subnanometer accuracy in three dimensions. One limitation of optical tweezers is the weak force that can be applied without thermal damage due to optical absorption. Acoustical tweezers overcome this limitation since the radiation pressure scales as the field intensity divided by the speed of propagation of the wave. However, the feasibility of single beam acoustical tweezers was demonstrated only recently. In this paper, we propose a historical review of the strong similarities but also the specificities of acoustical and optical radiation pressures, from the expression of the force to the development of single-beam acoustical tweezers.

  16. Visible-light beam size monitors using synchrotron radiation at CESR

    Energy Technology Data Exchange (ETDEWEB)

    Wang, S.T., E-mail: sw565@cornell.edu [Cornell Laboratory for Accelerator-Based Science and Education, Cornell University, Ithaca, NY 14853 (United States); Rubin, D.L.; Conway, J.; Palmer, M.; Hartill, D. [Cornell Laboratory for Accelerator-Based Science and Education, Cornell University, Ithaca, NY 14853 (United States); Campbell, R.; Holtzapple, R. [Physics Department, California Polytechnic State University, San Luis Obispo, CA 93407 (United States)

    2013-03-01

    A beam profile monitor utilizing visible synchrotron radiation (SR) from a bending magnet has been designed and installed in Cornell Electron-Positron Storage Ring (CESR). The monitor employs a double-slit interferometer to measure both the horizontal and vertical beam sizes over a wide range of beam currents. By varying the separation of the slits, beam sizes ranging from 50 to 500 μm can be measured with a resolution of approximately 5 μm. To measure larger beam size (>500 μm), direct imaging can be employed by rotating the double slits away from SR beam path. By imaging the π-polarized component of SR, a small vertical beam size (∼70 μm) was measured during an undulator test run in CESR, which was consistent with the interferometer measurement. To measure the bunch length, a beam splitter is inserted to direct a fraction of light into a streak camera setup. This beam size monitor measures the transverse and longitudinal beam sizes simultaneously, which is successfully used for intrabeam scattering studies. Detailed error analysis is discussed.

  17. Acoustical radiation torque and force for spheres and Bessel beam extinction efficiency

    Science.gov (United States)

    Marston, Philip L.; Zhang, Likun

    2014-11-01

    The scattering of optical and acoustical beams is relevant to the levitation and manipulation of drops. Here we examine theoretical developments in the acoustical case. We previously showed how the optical theorem for extinction can be extended to invariant beams. The example of a sphere in a Bessel beam facilitates the direct comparison with a circular disc computed using Babinet's principle and the Kirchhoff approximation. In related work, by considering traveling or standing wave first-order vortex beams we previously showed that the radiation torque is the ratio of the absorbed power and the radian acoustic frequency. By modifying the scattering to account for the viscosity of the surrounding fluid in the analysis of the absorbed power, approximations for radiation torque and force are obtained at long wavelengths in special cases and these can be compared with results published elsewhere.

  18. Radionuclides in radiation-induced bystander effect; may it share in radionuclide therapy?

    Science.gov (United States)

    Widel, M

    2017-01-01

    For many years in radiobiology and radiotherapy predominated the conviction that cellular DNA is the main target for ionizing radiation, however, the view has changed in the past 20 years. Nowadays, it is assumed that not only directed (targeted) radiation effect, but also an indirect (non-targeted) effect may contribute to the result of radiation treatment. Non-targeted effect is relatively well recognized after external beam irradiation in vitro and in vivo, and comprises such phenomena like radiation-induced bystander effect (RIBE), genomic instability, adaptive response and abscopal (out of field) effect. These stress-induced and molecular signaling mediated phenomena appear in non-targeted cells as variety responses resembling that observed in directly hit cells. Bystander effects can be both detrimental and beneficial in dependence on dose, dose-rate, cell type, genetic status and experimental condition. Less is known about radionuclide-induced non-targeted effects in radionuclide therapy, although, based on characteristics of the radionuclide radiation, on experiments in vitro utilizing classical and 3-D cell cultures, and preclinical study on animals it seems obvious that exposure to radionuclide is accompanied by various bystander effects, mostly damaging, less often protective. This review summarizes existing data on radionuclide induced bystander effects comprising radionuclides emitting beta- and alpha-particles and Auger electrons used in tumor radiotherapy and diagnostics. So far, separation of the direct effect of radionuclide decay from crossfire and bystander effects in clinical targeted radionuclide therapy is impossible because of the lack of methods to assess whether, and to what extent bystander effect is involved in human organism. Considerations on this topic are also included.

  19. Radiation-induced gene expression in human subcutaneous fibroblasts is predictive of radiation-induced fibrosis

    DEFF Research Database (Denmark)

    Rødningen, Olaug Kristin; Børresen-Dale, Anne-Lise; Alsner, Jan

    2008-01-01

    BACKGROUND AND PURPOSE: Breast cancer patients show a large variation in normal tissue reactions after ionizing radiation (IR) therapy. One of the most common long-term adverse effects of ionizing radiotherapy is radiation-induced fibrosis (RIF), and several attempts have been made over the last...... years to develop predictive assays for RIF. Our aim was to identify basal and radiation-induced transcriptional profiles in fibroblasts from breast cancer patients that might be related to the individual risk of RIF in these patients. MATERIALS AND METHODS: Fibroblast cell lines from 31 individuals......-treated fibroblasts. Transcriptional differences in basal and radiation-induced gene expression profiles were investigated using 15K cDNA microarrays, and results analyzed by both SAM and PAM. RESULTS: Sixty differentially expressed genes were identified by applying SAM on 10 patients with the highest risk of RIF...

  20. Application of radiation-induced apoptosis in radiation oncology and radiation protection

    International Nuclear Information System (INIS)

    Crompton, N.E.A.; Emery, G.C.; Ozsahin, M.; Menz, R.; Knesplova, L.; Larsson, B.

    1997-01-01

    A rapid assay of the ability of lymphocytes to respond to radiation-induced damage is presented. Age and genetic dependence of radiation response have been quantified. The assay is sensitive to low doses of radiation. Its ability to assess the cytotoxic response of blood capillaries to radiation has been evaluated. (author)