WorldWideScience

Sample records for accelerated radiotherapy hart

  1. Hadron accelerators for radiotherapy

    Science.gov (United States)

    Owen, Hywel; MacKay, Ranald; Peach, Ken; Smith, Susan

    2014-04-01

    Over the last twenty years the treatment of cancer with protons and light nuclei such as carbon ions has moved from being the preserve of research laboratories into widespread clinical use. A number of choices now exist for the creation and delivery of these particles, key amongst these being the adoption of pencil beam scanning using a rotating gantry; attention is now being given to what technologies will enable cheaper and more effective treatment in the future. In this article the physics and engineering used in these hadron therapy facilities is presented, and the research areas likely to lead to substantive improvements. The wider use of superconducting magnets is an emerging trend, whilst further ahead novel high-gradient acceleration techniques may enable much smaller treatment systems. Imaging techniques to improve the accuracy of treatment plans must also be developed hand-in-hand with future sources of particles, a notable example of which is proton computed tomography.

  2. Sergiu Hart

    DEFF Research Database (Denmark)

    Hansen, Pelle Guldborg

    2007-01-01

    In this interview Sergiu Hart, President of the Game Theory Society talks about how Robert Aumann got him into doing game theory, chracterizes good game theoretic research, the sure-thing principle of Savage, the limits of rationality and the most important problems in game theory today.......In this interview Sergiu Hart, President of the Game Theory Society talks about how Robert Aumann got him into doing game theory, chracterizes good game theoretic research, the sure-thing principle of Savage, the limits of rationality and the most important problems in game theory today....

  3. Hyperfractionated Accelerated Radiation Therapy (HART) of 70.6 Gy With Concurrent 5-FU/Mitomycin C Is Superior to HART of 77.6 Gy Alone in Locally Advanced Head and Neck Cancer: Long-term Results of the ARO 95-06 Randomized Phase III Trial

    Energy Technology Data Exchange (ETDEWEB)

    Budach, Volker, E-mail: volker.budach@charite.de [Department of Radiation Oncology, Charité Universitätsmedizin Berlin (Germany); Stromberger, Carmen [Department of Radiation Oncology, Charité Universitätsmedizin Berlin (Germany); Poettgen, Christoph [Department of Radiation Oncology, University Hospital of Essen (Germany); Baumann, Michael [Department of Radiation Oncology, University Hospital of Dresden (Germany); Budach, Wilfried [Department of Radiation Oncology, Heinrich Heine Universität Düsseldorf (Germany); Grabenbauer, Gerhard [Department of Radiation Oncology, University Hospitals of Erlangen (Germany); Marnitz, Simone [Department of Radiation Oncology, Charité Universitätsmedizin Berlin (Germany); Olze, Heidi [Department of Head and Neck Surgery, Charité Universitätsmedizin Berlin (Germany); Wernecke, Klaus-Dieter [Sostana GmbH, Berlin (Germany); Ghadjar, Pirus [Department of Radiation Oncology, Charité Universitätsmedizin Berlin (Germany)

    2015-04-01

    Purpose: To report the long-term results of the ARO 95-06 randomized trial comparing hyperfractionated accelerated chemoradiation with mitomycin C/5-fluorouracil (C-HART) with hyperfractionated accelerated radiation therapy (HART) alone in locally advanced head and neck cancer. Patients and Methods: The primary endpoint was locoregional control (LRC). Three hundred eighty-four patients with stage III (6%) and IV (94%) oropharyngeal (59.4%), hypopharyngeal (32.3%), and oral cavity (8.3%) cancer were randomly assigned to 30 Gy/2 Gy daily followed by twice-daily 1.4 Gy to a total of 70.6 Gy concurrently with mitomycin C/5-FU (C-HART) or 16 Gy/2 Gy daily followed by twice-daily 1.4 Gy to a total dose of 77.6 Gy alone (HART). Statistical analyses were done with the log-rank test and univariate and multivariate Cox regression analyses. Results: The median follow-up time was 8.7 years (95% confidence interval [CI]: 7.8-9.7 years). At 10 years, the LRC rates were 38.0% (C-HART) versus 26.0% (HART, P=.002). The cancer-specific survival and overall survival rates were 39% and 10% (C-HART) versus 30.0% and 9% (HART, P=.042 and P=.049), respectively. According to multivariate Cox regression analysis, the combined treatment was associated with improved LRC (hazard ratio [HR]: 0.6 [95% CI: 0.5-0.8; P=.002]). The association between combined treatment arm and increased LRC appeared to be limited to oropharyngeal cancer (P=.003) as compared with hypopharyngeal or oral cavity cancer (P=.264). Conclusions: C-HART remains superior to HART in terms of LRC. However, this effect may be limited to oropharyngeal cancer patients.

  4. Radiotherapy using a laser proton accelerator

    CERN Document Server

    Murakami, Masao; Miyajima, Satoshi; Okazaki, Yoshiko; Sutherland, Kenneth L; Abe, Mitsuyuki; Bulanov, Sergei V; Daido, Hiroyuki; Esirkepov, Timur Zh; Koga, James; Yamagiwa, Mitsuru; Tajima, Toshiki

    2008-01-01

    Laser acceleration promises innovation in particle beam therapy of cancer where an ultra-compact accelerator system for cancer beam therapy can become affordable to a broad range of patients. This is not feasible without the introduction of a technology that is radically different from the conventional accelerator-based approach. The laser acceleration method provides many enhanced capabilities for the radiation oncologist. It reduces the overall system size and weight by more than one order of magnitude. The characteristics of the particle beams (protons) make them suitable for a class of therapy that might not be possible with the conventional accelerator, such as the ease for changing pulse intensity, the focus spread, the pinpointedness, and the dose delivery in general. A compact, uncluttered system allows a PET device to be located in the vicinity of the patient in concert with the compact gantry. The radiation oncologist may be able to irradiate a localized tumor by scanning with a pencil-like particle...

  5. Interview with Keith Hart

    OpenAIRE

    2006-01-01

    One hour interview, filmed and interviewed by Alan Macfarlane, takes the life to 1984... Hopefully to be continued Interview of Keith Hart on 12th April 2006 at the Association of Social Anthropologists Conference at Keele University

  6. Myelopathy following hyperfractionated accelerated radiotherapy for anaplastic thyroid carcinoma.

    Science.gov (United States)

    Wong, C S; Van Dyk, J; Simpson, W J

    1991-01-01

    From 1975 to 1982, 32 patients with a diagnosis of anaplastic carcinoma of the thyroid were entered into a protocol of hyperfractionated accelerated radiotherapy. The tumor dose was 30-45 Gy at 1 Gy per fraction given 4 times a day at 3-h intervals. The results were disappointing with a median survival of less than 6 months. Two patients developed radiation myelopathy at 8 and 13 months, total spinal cord dose being 39.9 and 48.3 Gy, respectively. The risk of spinal cord damage was much higher than expected. The possible radiobiological causes and clinical implications are discussed.

  7. Accelerated Deformable Registration of Repetitive MRI during Radiotherapy in Cervical Cancer

    DEFF Research Database (Denmark)

    Noe, Karsten Østergaard; Tanderup, Kari; Kiritsis, Christian;

    2006-01-01

    Tumour regression and organ deformations during radiotherapy (RT) of cervical cancer represent major challenges regarding accurate conformation and calculation of dose when using image-guided adaptive radiotherapy. Deformable registration algorithms are able to handle organ deformations, which can...... be useful with advanced tools such as auto segmentation of organs and dynamic adaptation of radiotherapy. The aim of this study was to accelerate and validate deformable registration in MRI-based image-guided radiotherapy of cervical cancer.    ...

  8. Fractionated Stereotactic Radiotherapy of Vestibular Schwannomas Accelerates Hearing Loss

    Energy Technology Data Exchange (ETDEWEB)

    Rasmussen, Rune, E-mail: rune333@gmail.com [Department of Neurosurgery, Rigshospitalet, Copenhagen (Denmark); Claesson, Magnus [Department of Neurosurgery, Rigshospitalet, Copenhagen (Denmark); Stangerup, Sven-Eric [Ear, Nose, and Throat Department, Rigshospitalet, Copenhagen (Denmark); Roed, Henrik [Department of Radiation Oncology, Rigshospitalet, Copenhagen (Denmark); Christensen, Ib Jarle [Finsen Laboratory, Rigshospitalet, Copenhagen (Denmark); Caye-Thomasen, Per [Ear, Nose, and Throat Department, Rigshospitalet, Copenhagen (Denmark); Juhler, Marianne [Department of Neurosurgery, Rigshospitalet, Copenhagen (Denmark)

    2012-08-01

    Objective: To evaluate long-term tumor control and hearing preservation rates in patients with vestibular schwannoma treated with fractionated stereotactic radiotherapy (FSRT), comparing hearing preservation rates to an untreated control group. The relationship between radiation dose to the cochlea and hearing preservation was also investigated. Methods and Materials: Forty-two patients receiving FSRT between 1997 and 2008 with a minimum follow-up of 2 years were included. All patients received 54 Gy in 27-30 fractions during 5.5-6.0 weeks. Clinical and audiometry data were collected prospectively. From a 'wait-and-scan' group, 409 patients were selected as control subjects, matched by initial audiometric parameters. Radiation dose to the cochlea was measured using the original treatment plan and then related to changes in acoustic parameters. Results: Actuarial 2-, 4-, and 10-year tumor control rates were 100%, 91.5%, and 85.0%, respectively. Twenty-one patients had serviceable hearing before FSRT, 8 of whom (38%) retained serviceable hearing at 2 years after FSRT. No patients retained serviceable hearing after 10 years. At 2 years, hearing preservation rates in the control group were 1.8 times higher compared with the group receiving FSRT (P=.007). Radiation dose to the cochlea was significantly correlated to deterioration of the speech reception threshold (P=.03) but not to discrimination loss. Conclusion: FSRT accelerates the naturally occurring hearing loss in patients with vestibular schwannoma. Our findings, using fractionation of radiotherapy, parallel results using single-dose radiation. The radiation dose to the cochlea is correlated to hearing loss measured as the speech reception threshold.

  9. Fractionated stereotactic radiotherapy of vestibular schwannomas accelerates hearing loss

    DEFF Research Database (Denmark)

    Rasmussen, Rune; Claesson, Magnus; Stangerup, Sven-Eric

    2012-01-01

    To evaluate long-term tumor control and hearing preservation rates in patients with vestibular schwannoma treated with fractionated stereotactic radiotherapy (FSRT), comparing hearing preservation rates to an untreated control group. The relationship between radiation dose to the cochlea...... and hearing preservation was also investigated....

  10. Prolonged survival when temozolomide is added to accelerated radiotherapy for glioblastoma multiforme

    Energy Technology Data Exchange (ETDEWEB)

    Guckenberger, Matthias; Mayer, Mario; Sweeney, Reinhart A.; Flentje, Michael [University Hospital Wuerzburg (Germany). Dept. of Radiation Oncology; Buttmann, Mathias [University Hospital Wuerzburg (Germany). Dept. of Neurology; Vince, Giles H. [University Hospital Wuerzburg (Germany). Dept. of Neurosurgery

    2011-09-15

    The goal of this study was to evaluate accelerated radiotherapy with and without temozolomide (TMZ) for glioblastoma multiforme (GBM). This retrospective analysis evaluated 86 patients with histologically proven GBM who were treated with accelerated radiotherapy of 1.8 Gy twice daily to a total dose of 54 Gy within 3 weeks. Median age was 62 years and median Karnofsky index was 90. A total of 41 patients received radiotherapy only from 2002-2005 and 45 patients were treated with TMZ concomitantly and after radiotherapy from 2005-2007. Median overall survival (OS) was 12.5 months and 2-year OS was 15.4%. Patient characteristics were well balanced between the two groups except for better performance status (p = 0.05) and higher frequency of retreatment for the first recurrence (p = 0.02) in the TMZ group. Age at diagnosis (HR 2.83) and treatment with TMZ (HR 0.60) were correlated with OS in the multivariate analysis: treatment with and without TMZ resulted in median OS of 16 months and 11.3 months, respectively. Hematological toxicity grade > II was observed in 2/45 patients and 5/37 patients during simultaneous radiochemotherapy and adjuvant TMZ. TMZ added to accelerated radiotherapy for GBM resulted in prolonged overall survival with low rates of severe hematological toxicity. (orig.)

  11. Parodontitis en hart- en vaatziekten

    NARCIS (Netherlands)

    Teeuw, W.J.; Loos, B.G.

    2013-01-01

    Uit verscheidene onderzoeken is gebleken dat er een duidelijke associatie bestaat tussen parodontitis en hart- en vaatziekten. Mogelijke verklaringen hiervoor zijn: (1) het pocketepitheel kan fungeren als porte d’entrée voor bacteriën en zo leiden tot een bacteriëmie, en (2) parodontitis leidt tot e

  12. The HART I augmented electric gun facility

    Energy Technology Data Exchange (ETDEWEB)

    Fikse, D.A.; Ciesar, J.A.; Wehrli, H.A.; Rimersma, H.; Docherty, E.F.; Pipich, C.W. (Westinghouse Science and Technology Center, Pittsburgh, PA (US))

    1991-01-01

    This paper reports on an augmented electric gun system that has been commissioned. This system, called HART I (Hypervelocity Augmented Railgun Test), is built around a double augmented rail arrangement with a 1.27-cm square bore. It is powered by the SUVAC II 5.6-MJ distributed capacitor power supply. This arrangement allows operation in a simple, series augmented, or transaugmented gun system configuration. The objective of this facility is to perform materials research augmentation studies, and armature development in the 10-km/s regime. Armature masses of 2 to 4 g will be accelerated in a 4-m long barrel. Baseline bore materials will begin with conventional G9/GlidCop systems and then move into pyrolytic boron nitride/refractory materials. Hybrids, plasma, and ablation stabilized armature systems are planned. The gun system is instrumented with plasma and rail B-dot probes for inbore velocity measurements. In addition, breech and muzzle voltages, currents, and external velocities are measured. The HART I system is currently performing hypervelocity experiments to verify the augmentation models.

  13. Acceleration of pubertal development following pituitary radiotherapy for Cushing's disease

    Energy Technology Data Exchange (ETDEWEB)

    Nicholl, R.M.; Kirk, J.M.W.; Grossman, A.B.; Plowman, P.N.; Besser, G.M.; Savage, M.O. (Saint Bartholomew' s Hospital, London (United Kingdom))

    1993-01-01

    A 7-year-old boy with pituitary dependent Cushing's disease was treated with pituitary irradiation following unsuccessful microadenomectomy. This led to normalization of the hypercortisolaemia, but was followed by GH deficiency. Two years after radiotherapy he had the onset of pubertal development with testicular enlargement to 8 ml bilaterally. Pubertal regression was induced using the long-acting GnRH analogue goserelin. Acceleration of skeletal maturation was also arrested, resulting in improvement of final height prediction. Irradiation directly to the hypothalamo-pituitary region, as well as whole brain irradiation, may thus be associated with accelerated pubertal development. (author).

  14. Hart, Dworkin e discricionariedade Hart, Dworkin and discretion

    Directory of Open Access Journals (Sweden)

    Daniela R. Ikawa

    2004-01-01

    Full Text Available A questão central discutida neste artigo é a existência ou não de um dever legal do juiz de decidir de uma determinada forma em caso de 'lacuna da lei', termo empregado por H. L. A. Hart, ou em 'casos difíceis', termo adotado por Ronald Dworkin. Este artigo conclui que embora Hart e Dworkin admitam uma forma fraca de discricionariedade judicial, eles adotam visões opostas quanto à existência daquele dever. Ao defender uma noção de completude legal, ao discordar da regra social de reconhecimento e ao incluir princípios não convencionais no conceito de direito, Dworkin fundamenta a existência daquele dever judicial, oferecendo critérios objetivos de decisão mesmo para casos difíceis.The central issue discussed in this article is whether a judge has a legal duty to decide in an specific manner in cases of legal lacunae, to use H. L. A. Hart's expression, or in hard cases, to use Ronald Dworkin's expression. It argues that, though both Hart and Dworkin admit a weak form of judicial discretion, they hold opposite views on the existence of that duty. By adopting a notion of legal completeness, which may disagree with a social rule of recognition, and by including non-conventional principles in the concept of Law, Dworkin offers the justification for that judicial duty. He also offers objective criteria of judicial decision even in hard cases.

  15. Radiotherapy

    Directory of Open Access Journals (Sweden)

    Rema Jyothirmayi

    1999-01-01

    Full Text Available Purpose. Conservative treatment in the form of limited surgery and post-operative radiotherapy is controversial in hand and foot sarcomas, both due to poor radiation tolerance of the palm and sole, and due to technical difficulties in achieving adequate margins.This paper describes the local control and survival of 41 patients with soft tissue sarcoma of the hand or foot treated with conservative surgery and radiotherapy. The acute and late toxicity of megavoltage radiotherapy to the hand and foot are described. The technical issues and details of treatment delivery are discussed. The factors influencing local control after radiotherapy are analysed.

  16. Visual Outcome in Meningiomas Around Anterior Visual Pathways Treated With Linear Accelerator Fractionated Stereotactic Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Stiebel-Kalish, Hadas, E-mail: kalishhadas@gmail.com [Neuro-Ophthalmology Unit, Rabin Medical Center, Petah Tikva (Israel); Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel); Reich, Ehud [Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel); Department of Ophthalmology, Rabin Medical Center, Petah Tikva (Israel); Gal, Lior [Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel); Rappaport, Zvi Harry [Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel); Department of Neurosurgery, Rabin Medical Center, Petah Tikva (Israel); Nissim, Ouzi [Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel); Stereotactic Radiosurgery Unit, Sheba Medical Center, Ramat Gan (Israel); Department of Neurosurgery, Sheba Medical Center, Ramat Gan (Israel); Pfeffer, Raphael [Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel); Stereotactic Radiosurgery Unit, Sheba Medical Center, Ramat Gan (Israel); Spiegelmann, Roberto [Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel); Stereotactic Radiosurgery Unit, Sheba Medical Center, Ramat Gan (Israel); Department of Neurosurgery, Sheba Medical Center, Ramat Gan (Israel)

    2012-02-01

    Purpose: Meningiomas threatening the anterior visual pathways (AVPs) and not amenable for surgery are currently treated with multisession stereotactic radiotherapy. Stereotactic radiotherapy is available with a number of devices. The most ubiquitous include the gamma knife, CyberKnife, tomotherapy, and isocentric linear accelerator systems. The purpose of our study was to describe a case series of AVP meningiomas treated with linear accelerator fractionated stereotactic radiotherapy (FSRT) using the multiple, noncoplanar, dynamic conformal rotation paradigm and to compare the success and complication rates with those reported for other techniques. Patients and Methods: We included all patients with AVP meningiomas followed up at our neuro-ophthalmology unit for a minimum of 12 months after FSRT. We compared the details of the neuro-ophthalmologic examinations and tumor size before and after FSRT and at the end of follow-up. Results: Of 87 patients with AVP meningiomas, 17 had been referred for FSRT. Of the 17 patients, 16 completed >12 months of follow-up (mean 39). Of the 16 patients, 11 had undergone surgery before FSRT and 5 had undergone FSRT as first-line management. Tumor control was achieved in 14 of the 16 patients, with three meningiomas shrinking in size after RT. Two meningiomas progressed, one in an area that was outside the radiation field. The visual function had improved in 6 or stabilized in 8 of the 16 patients (88%) and worsened in 2 (12%). Conclusions: Linear accelerator fractionated RT using the multiple noncoplanar dynamic rotation conformal paradigm can be offered to patients with meningiomas that threaten the anterior visual pathways as an adjunct to surgery or as first-line treatment, with results comparable to those reported for other stereotactic RT techniques.

  17. Vertical mammaplasty associated with accelerated partial breast radiotherapy: how oncoplastic surgery techniques associated with modern techniques of radiotherapy can improve the aesthetic outcome in selected patients

    Energy Technology Data Exchange (ETDEWEB)

    Couto, Henrique Lima, E-mail: enriquecouto@hotmail.com [Santa Fe Women' s and Maternity Hospital, Belo Horizonte, MG (Brazil); Amorim, Washington Cancado; Guimaraes, Rodrigo [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Hospital Geral; Ramires, Leandro Cruz; Castilho, Marcus Simoes [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Fac. de Medicina; Dominguez, Lorena Lima Coto [Universidade Estacio de Sa (UNESA), Rio de Janeiro, EJ (Brazil)

    2014-07-15

    Breast cancer is the second most common type of cancer in the world, being the most common among women, responsible for 22% of new cases each year. It's surgical and radiation treatment evolved from radical procedures (Halsted radical mastectomy and total external breast radiotherapy) to less radical and more conservative procedures. With the use of modern oncoplastic surgery techniques and accelerated partial breast radiotherapy, selected patients can benefit with better aesthetic results, fewer side effects, and more comfortable and brief treatments. (author)

  18. Hartebeesthoek Radio Astronomy Observatory (HartRAO)

    Science.gov (United States)

    Nickola, Marisa; Gaylard, Mike; Quick, Jonathan; Combrinck, Ludwig

    2013-01-01

    HartRAO provides the only fiducial geodetic site in Africa, and it participates in global networks for VLBI, GNSS, SLR, and DORIS. This report provides an overview of geodetic VLBI activities at HartRAO during 2012, including the conversion of a 15-m alt-az radio telescope to an operational geodetic VLBI antenna.

  19. Acute toxicity profile and compliance to accelerated radiotherapy plus carbogen and nicotinamide for clinical stage T2-4 laryngeal cancer: results of a phase III randomized trial.

    NARCIS (Netherlands)

    Janssens, G.O.R.J.; Terhaard, C.H.J.; Doornaert, P.A.; Bijl, H.P.; Ende, P. van den; Chin, A.; Pop, L.A.M.; Kaanders, J.H.A.M.

    2012-01-01

    PURPOSE: To report the acute toxicity profile and compliance from a randomized Phase III trial comparing accelerated radiotherapy (AR) with accelerated radiotherapy plus carbogen and nicotinamide (ARCON) in laryngeal cancer. METHODS AND MATERIALS: From April 2001 to February 2008, 345 patients with

  20. ACUTE TOXICITY PROFILE AND COMPLIANCE TO ACCELERATED RADIOTHERAPY PLUS CARBOGEN AND NICOTINAMIDE FOR CLINICAL STAGE T2-4 LARYNGEAL CANCER : RESULTS OF A PHASE III RANDOMIZED TRIAL

    NARCIS (Netherlands)

    Janssens, Geert O.; Terhaard, Chris H.; Doornaert, Patricia A.; Bijl, Hendrik P.; van den Ende, Piet; Chin, Alim; Pop, Lucas A.; Kaanders, Johannes H.

    2012-01-01

    Purpose: To report the acute toxicity profile and compliance from a randomized Phase III trial comparing accelerated radiotherapy (AR) with accelerated radiotherapy plus carbogen and nicotinamide (ARCON) in laryngeal cancer. Methods and Materials: From April 2001 to February 2008, 345 patients with

  1. Toxicity and cosmetic outcome of three-dimensional conformal radiotherapy for accelerated partial breast irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Gatti, M.; Bresciani, S.; Ponzone, R.; Panaia, R.; Salatino, A.; Stasi, M.; Gabriele, P. [IRCC, Candiolo (Italy)

    2011-10-15

    Full text of publication follows: Purpose.- To analyse the incidence and severity of acute and late normal tissue toxicity and cosmetic outcome using three - dimensional conformal radiotherapy to deliver accelerated partial breast irradiation. Patients and Methods.- 70 patients with stage I disease were treated with three-dimensional conformal radiotherapy for accelerated partial breast irradiation, in an approved protocol. The prescribed dose was 34 Gy in all patients delivered in 10 fractions over 5 consecutive days. On all CT scans gross tumor volume (GTV ) was defined around surgical clips. A 1.5 cm margin was added in order to account for clinical target volume (CTV) . A margin of 1 cm was added to CTI to define the planning target volume (PTV). The dose-volume constraints were followed in accordance with the specifications as dictated in the NSABP/RTOG protocol. After treatment, patients underwent a clinical and cosmetic evaluation every 3 months. Late toxicity was evaluated according to the RTOG grading schema. The cosmetic assessment was performed by the physicians using the controlateral untreated breast as the reference (Harvard scale). Results.- Median patient age was 66 years (range 51-80). Median follow-up was 15 months (range 6-46). Tumor size was < 10 mm in 33 patients (53%) and > 2 cm in 4(6%). The mean value of the ratio between the PTV and the whole ipsilateral breast volume was 38 % and the median percentage whole breast volume that received 95 % of prescribed dose was 34% (range 16%-55%). The rate of G1 and G2 acute skin toxicity was 28% and 2% respectively and the late toxicity was 17% (G1). G2 or greater toxicities were not observed. The most pronounced G1 late toxicity was subcutaneous fibrosis, developed in 3 patients. The cosmetic outcome was excellent in 83% and good in 17%. Conclusion.- Accelerated partial breast irradiation using three-dimensional conformal radiotherapy is technically feasible with very low acute and late toxicity. Long

  2. Correlation between egfr expression and accelerated proliferation during radiotherapy of head and neck squamous cell carcinoma

    Directory of Open Access Journals (Sweden)

    Pedicini Piernicola

    2012-08-01

    Full Text Available Abstract Purpose To investigate the correlation between the expression of Epidermal Growth Factor receptor (EGFr and the reduction of the effective doubling time (TD during radiotherapy treatment and also to determine the dose per fraction to be taken into account when the overall treatment time (OTT is reduced in accelerated radiotherapy of head and neck squamous cell carcinoma (HNSCC. Methods A survey of the published papers comparing 3-years of local regional control rate (LCR for a total of 2162 patients treated with conventional and accelerated radiotherapy and with a pretreatment assessment of EGFr expression, was made. Different values of TD were obtained by a model incorporating the overall time corrected biologically effective dose (BED and a 3-year clinical LCR for high and low EGFr groups of patients (HEGFr and LEGFr, respectively. By obtaining the TD from the above analysis and the sub-sites’ potential doubling time (Tpot from flow cytometry and immunohistochemical methods, we were able to estimate the average TD for each sub-site included in the analysis. Moreover, the dose that would be required to offset the modified proliferation occurring in one day (Dprolif, was estimated. Results The averages of TD were 77 (27-9095% days in LEGFr and 8.8 (7.3-11.095% days in HEGFr, if an onset of accelerated proliferation TK at day 21 was assumed. The correspondent HEGFr sub-sites’ TD were 5.9 (6.6, 5.9 (6.6, 4.6 (6.1, 14.3 (12.9 days, with respect to literature immunohistochemical (flow cytometry data of Tpot for Oral-Cavity, Oro-pharynx, Hypo-pharynx, and Larynx respectively. The Dprolif for the HEGFr groups were 0.33 (0.29, 0.33 (0.29, 0.42 (0.31, 0.14 (0.15 Gy/day if α = 0.3 Gy-1 and α/β = 10 Gy were assumed. Conclusions A higher expression of the EGFr leads to enhanced proliferation. This study allowed to quantify the extent of the effect which EGFr expression has in terms of reduced TD and Dprolif for each head and neck

  3. Concurrent hyperfractionated accelerated radiotherapy with 5-FU and once weekly cisplatin in locally advanced head and neck cancer. The 10-year results of a prospective phase II trial

    Energy Technology Data Exchange (ETDEWEB)

    Budach, V.; Boehmer, D.; Badakhshi, H.; Jahn, U.; Stromberger, C. [Campus Virchow Klinikum, Charite Universitaetsmedizin Berlin, Department for Radiooncology, Clinic for Radiooncology, Berlin (Germany); Becker, E.T. [Charite Universitaetsmedizin, Department of Otorhinolaryngology, Berlin (Germany); Wernecke, K.D. [Sostana Statistics GmbH, Charite Universitaetsmedizin Berlin, Berlin (Germany)

    2014-03-15

    In this study, the acute toxicity and long-term outcome of a hyperfractionated accelerated chemoradiation regimen with cisplatin/5-fluorouracil (5-FU) in patients with locally advanced squamous cell carcinomas of head and neck were evaluated. From 2000-2002, 38 patients with stage III (5.3 %) and stage IV (94.7 %) head and neck cancer were enrolled in a phase II study. Patients received hyperfractionated-accelerated radiotherapy with 72 Gy in 15 fractions of 2 Gy followed by 1.4 Gy twice daily with concurrent, continuous infusion 5-FU of 600 mg/m{sup 2} on days 1-5 and 6 cycles of weekly cisplatin (30 mg/m{sup 2}). Acute toxicities (CTCAEv2.0), locoregional control (LRC), metastases-free (MFS), and overall survival (OS) were analyzed and exploratively compared with the ARO 95-06 trial. Median follow-up was 11.4 years (95 % CI 8.6-14.2) and mean dose 71.6 Gy. Of the patients, 82 % had 6 (n = 15) or 5 (n = 16) cycles of cisplatin, 5 and 2 patients received 4 and 3 cycles, respectively. Grade 3 anemia, leukopenia, and thrombocytopenia were observed in 15.8, 15.8, and 2.6 %, respectively. Grade 3 mucositis in 50 %, grade 3 and 4 dysphagia in 55 and 13 %. The 2-, 5-, and 10-year LRC was 65, 53.6, and 48.2 %, the MFS was 77.5, 66.7, and 57.2 % and the OS 59.6, 29.2, and 15 %, respectively. Chemoradiation with 5-FU and cisplatin seems feasible and superior in terms of LRC and OS to the ARO 95-06C-HART arm at 2 years. However, this did not persist at the 5- and 10-year follow-ups. (orig.) [German] Untersuchung der Akuttoxizitaet und des Langzeitueberlebens einer hyperfraktioniert-akzelerierten simultanen Radiochemotherapie mit Cisplatin/5-Fluorouracil (5-FU) bei Patienten mit lokal fortgeschrittenen Kopf-Hals-Tumoren. Von 2000 bis 2002 wurden 38 Patienten mit Plattenepithelkarzinomen der Kopf-Hals-Region im Stadium III (5,3 %) und IV (94,7 %) eingeschlossen. Es erfolgte eine simultane hyperfraktionierte akzelerierte Radiochemotherapie mit 72 Gy in 15 Fraktionen a 2 Gy

  4. Short treatment time and excellent treatment outcome in accelerated hyperfractionated radiotherapy for T1 glottic cancer.

    Science.gov (United States)

    Tamaki, Yukihisa; Hieda, Yoko; Yoshida, Rika; Yoshizako, Takeshi; Fuchiwaki, Takafumi; Aoi, Noriaki; Sekihara, Kazumasa; Kitajima, Kazuhiro; Kawauchi, Hideyuki; Kitagaki, Hajime; Sasaki, Ryohei; Inomata, Taisuke

    2015-11-01

    Accelerated hyperfractionated radiotherapy was performed as treatment for patients with T1 glottic cancer, and its utility was evaluated based on treatment outcomes and adverse effects. Fifty-eight men who had undergone radiotherapy were retrospectively reviewed. Tumor classification was Tis in 4 patients, T1a in 38, and T1b in 16. Histological examination revealed squamous cell carcinoma in 55 patients. Travel time from home to hospital was 0-1 hour for 24 patients, 1-2 hours for 9, and >2 hours for 25. Laser vaporization was performed prior to radiotherapy in 38 patients, and 19 patients received concurrent chemotherapy with an agent such as S-1. Patients were irradiated twice daily using an irradiation container. Most patients received a dose of 1.5 Gy/fraction up to a total of 60 Gy. The median overall treatment time was 30 days, with a median observation period of 59.6 months. A complete response was observed in all patients. The 5-year overall survival, disease-free survival, and local control rates were 97.2%, 93.2%, and 97.8%, respectively. Although grade 3 pharyngeal mucositis was observed in 2 patients, there were no other grade 3 or higher acute adverse events. As late toxicity, grade 2 laryngeal edema and grade 1 laryngeal hemorrhage were observed in 1 patient each, but no serious events such as laryngeal necrosis or laryngeal stenosis were observed. In conclusion, this treatment method brings excellent outcome and will substantially reduce the treatment duration among patients who need to stay at nearby hotels while undergoing treatment at hospitals in rural areas.

  5. Cost-benefit analysis on radiotherapy services for cancer treatment, with LINAC type equipments (linear accelerators

    Directory of Open Access Journals (Sweden)

    Luiz Alberto Blois

    2014-12-01

    Full Text Available This work consists in analyzing the economic feasibility of the investment to implement a Radiotherapy sector for radiological of cancer treatment by type linear accelerators equipments, based on the case of a public hospital in São Paulo. From technical and financial details of the project and the survey reference values for health care to their procedures, the statistical outcome of treatment on patients' life expectancy and average income indicators of the state's population, were estimated to income (private and social and expenses of this health service and other elements that make up the flow of the investment project box. From these estimates we evaluated public and private investment return, ie, if it fits only on the public sector or if private sector could also implement this projects geared exclusively to free admittance.

  6. An intercomparison of neutron measurments for a 25 MV x-ray radiotherapy accelerator.

    Science.gov (United States)

    Nath, R; Price, K W; Holeman, G R

    1980-01-01

    High-energy x-ray radiotherapy machines produce neutrons by photonuclear reactions which present a potential radiation hazard to the personnel and patient. A series of measurements of the neutron flux from a 25 MV x-ray linear accelerator, inside and outside the treatment room, have been performed using a multisphere spectrometer, Nemo dosimeter, and activation detectors. These results are compared with other mixed photon-neutron field measurements for the same machine performed using an argon/propane ionization chamber, silicon diode, track-etching detectors, and Monte Carlo calculations. It is found that these measurements agree with each other within a factor of two except for silicon diode measurements in the photon beam. Measured neutron spectra at various locations in the treatment room are also compared with the results of Monte Carlo transport calculations.

  7. Five Year Outcome of 145 Patients With Ductal Carcinoma In Situ (DCIS) After Accelerated Breast Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Ciervide, Raquel [Department of Radiation Oncology, New York University School of Medicine, NYU Langone Medical Center, New York, New York (United States); Dhage, Shubhada; Guth, Amber; Shapiro, Richard L.; Axelrod, Deborah M.; Roses, Daniel F. [Department of Surgery, New York University School of Medicine, NYU Langone Medical Center, New York, New York (United States); Formenti, Silvia C., E-mail: silvia.formenti@nyumc.org [Department of Radiation Oncology, New York University School of Medicine, NYU Langone Medical Center, New York, New York (United States)

    2012-06-01

    Background: Accelerated whole-breast radiotherapy (RT) with tumor bed boost in the treatment of early invasive breast cancer has demonstrated equivalent local control and cosmesis when compared with standard RT. Its efficacy in the treatment of ductal carcinoma in situ (DCIS) remains unknown. Methods and Materials: Patients treated for DCIS with lumpectomy and negative margins were eligible for 2 consecutive hypofractionated whole-breast RT clinical trials. The first trial (New York University [NYU] 01-51) prescribed to the whole breast 42 Gy (2.8 Gy in 15 fractions) and the second trial (NYU 05-181) 40.5 Gy (2.7 Gy in 15 fractions) with an additional daily boost of 0.5 Gy to the surgical cavity. Results: Between 2002 and 2009, 145 DCIS patients accrued, 59 to the first protocol and 86 to the second trial. Median age was 56 years and 65% were postmenopausal at the time of treatment. Based on optimal sparing of normal tissue, 79% of the patients were planned and treated prone and 21% supine. At 5 years' median follow-up (60 months; range 2.6-105.5 months), 6 patients (4.1%) experienced an ipsilateral breast recurrence in all cases of DCIS histology. In 3/6 patients, recurrence occurred at the original site of DCIS and in the remaining 3 cases outside the original tumor bed. New contralateral breast cancers arose in 3 cases (1 DCIS and 2 invasive carcinomas). Cosmetic self-assessment at least 2 years after treatment is available in 125 patients: 91% reported good-to-excellent and 9% reported fair-to-poor outcomes. Conclusions: With a median follow-up of 5 years, the ipsilateral local recurrence rate is 4.1%, comparable to that reported from the NSABP (National Surgical Adjuvant Breast and Bowel Project) trials that employed 50 Gy in 25 fractions of radiotherapy for DCIS. There were no invasive recurrences. These results provide preliminary evidence that accelerated hypofractionated external beam radiotherapy is a viable option for DCIS.

  8. Sheldon-Hart - High Desert Weed Management

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — (1)Treat 500 acres of previously mapped invasive weeds on Hart Mountain; followup monitoring and spot treatment where needed, (2)treat 110 acres of invasive weeds...

  9. Does accelerated hypofractionated adjuvant whole-breast radiotherapy increase mammographic density or change mammographic features?

    Science.gov (United States)

    Milanesio, Luisella; Brachet Cota, Piero B; Berrino, Carla; Cataldi, Aldo; Gatti, Giovanni; Mondini, Guido; Paino, Ovidio; Comello, Erika G; Orlassino, Renzo; Pasquino, Massimo; Cante, Domenico; La Porta, Maria R; Patania, Sebastiano; La Valle, Giovanni

    2015-01-01

    Objective: To compare mammographic features before and after accelerated hypofractionated adjuvant whole-breast radiotherapy (AWB-RT) and to evaluate possible appearance of modifications. Methods: A retrospective review of 177 females before and after an AWB-RT treatment (follow-up ranging from 5 to 9 years) was performed by four radiologists focused in breast imaging who independently evaluated diffuse mammographic density patterns and reported on possible onset of focal alterations; modifications in density and fibrosis with parenchymal distortion were deemed as indicators of AWB-RT treatment impact in breast imaging. Results: Prevalent mammographic density (D) patterns in the 177 females evaluated were according to the American College of Radiology–Breast Imaging Reporting and Data System (ACR-BIRADS): D1, fibroadipose density (score percentage from 55.9% to 43.5%); and D2, scattered fibroglandular density (from 42.9% to 32.7%). No change in diffuse mammographic density and no significant difference in mammographic breast parenchymal structure were observed. “No change” was reported with score percentage from 87% to 79.6%. Appearance of fibrosis with parenchymal distortion was reported by all radiologists in only two cases (1.1%, p = 0.3); dystrophic calcification was identified with percentage score from 2.2% to 3.3% (small type) and from 9.6% to 12.9% (coarse type). Conclusion: No statistically significant changes in follow-up mammographies 5–9 years after AWB-RT were detected, justifying large-scale selection of AWB-RT treatment with no risk of altering radiological breast parameters of common use in tumour recurrence detection. Advances in knowledge: The hypofractionated radiotherapy (AWB-RT treatment) is a new proven, safe and effective modality in post-operative patients with early breast cancer with excellent local control and survival. In our study, the absence of changes in mammographic density patterns and in breast imaging before and after

  10. Short-course radiotherapy in elderly patients with glioblastoma. Feasibility and efficacy of results from a single centre

    Energy Technology Data Exchange (ETDEWEB)

    Fariselli, L.; Pinzi, V.; Milanesi, I.; Marchetti, M. [Neurological Carlo Besta Institute Foundation, Milan (Italy). Dept. of Neurosurgery; Silvani, A.; Salmaggi, A. [Neurological Carlo Besta Institute Foundation, Milan (Italy). Div. of Neurooncology; Farinotti, M. [Neurological Carlo Besta Institute Foundation, Milan (Italy). Epidemiology Unit

    2013-06-15

    Background: The incidence of glioblastoma (GBM) in the elderly population is currently increasing, with a peak seen between 65 and 84 years. The optimal treatment in terms of both efficacy and quality of life still remains a relevant and debated issue today. The purpose of our study was to evaluate the feasibility of short-course hypofractionated accelerated radiotherapy (HART) in GBM patients aged over 70 years and with a good Karnofsky performance score (KPS). Methods: A review of medical records at the 'Istituto Neurologico C. Besta' was undertaken; patients aged {>=} 70 years who had undergone adjuvant HART for GBM between January 2000 and January 2004 were included in the study. HART was administered to a total dose of 45 Gy, 2.5 Gy/fraction, in three daily fractions for three consecutive days/cycle fractions each, delivered in two cycles (split 15 days). Results: A total of 33 patients were evaluable for the current analysis. Median follow-up was 10 months. According to CTCAE (version 3.0) criteria, none of the patients developed radiation-induced neurological status deterioration or necrosis. KPS evaluation after HART was found to be stable in 73 % of patients, improved in 24 %, and worse in 3 %. The median overall survival time of the entire study population was 8 months (range 2-24). Conclusions: Our findings suggest that a hypofractionated accelerated schedule can be a safe and effective option in the treatment of GBM in the elderly. (orig.)

  11. Can pure accelerated radiotherapy given as six fractions weekly be an option in locally advanced carcinoma cervix: Results of a prospective randomized phase III trial

    Directory of Open Access Journals (Sweden)

    Mukesh Sharma

    2016-01-01

    Conclusions: Accelerated radiotherapy given as six fractions per week is an effective alternative to concomitant chemoradiation in locally advanced carcinoma cervix and has shown lesser toxicities in our study.

  12. Theoretical aspects of implementation of kilovoltage cone-beam CT onboard linear accelerator for image-guided radiotherapy.

    Science.gov (United States)

    Rodríguez Cordón, Marta; Ferrer Albiach, Carlos

    2009-08-01

    The main objective of image-guided radiation therapy (IGRT) equipment is to reduce and correct inherent errors in external radiotherapy processes. At the present time, there are different IGRT systems available, but here we will refer exclusively to the kilovoltage cone-beam CT onboard linear accelerator (CBkVCT) and the different aspects that, from a clinical point of view, should be taken into consideration before the implementation of this equipment.

  13. Retrospective study on therapy options of brain metastases surgery versus stereotactic radiotherapy with the linear accelerator

    CERN Document Server

    Fortunati, M K S

    2001-01-01

    Background: in the therapy of brain metastases there has been a great progress in the last years. It was shown, that more aggressive therapies can not only extend the survival of the patients, but also improve quality of life. The major question of this study was, whether surgery or stereotactic radiotherapy with the linear accelerator show better results in behalf of the survival. Beside this major question many parameters regarding the patient or his primary cancer were examined. Methods: from the 1st of January 1995 until the 30th of June 2000 233 patients with one or more brain metastases have been treated in the Wagner Jauregg Landesnervenkrankenhaus Oberoesterreich (WJ LNKH OeO). The LINAC has been established on the 1st of July 1997. The patients have been distributed in three groups: 1. LINAC-group: 81 patients have been treated from the 1st of July 1997 until the 30th of June 2000 with the LINAC. 2. Surgery-group: 81 patients have been operated from the 1st of July 1997 until the 30th June 2000. 3 Co...

  14. Short-Course Accelerated Radiotherapy in Palliative Treatment of Advanced Pelvic Malignancies: A Phase I Study

    Energy Technology Data Exchange (ETDEWEB)

    Caravatta, Luciana [Department of Radiation Oncology, Fondazione di Ricercae Cura ' Giovanni Paolo II,' Universita Cattolica del S. Cuore, Campobasso (Italy); Padula, Gilbert D.A. [Department of Radiation Oncology, Lacks Cancer Center Saint Mary' s Health Care, Grand Rapids, MI (United States); Macchia, Gabriella, E-mail: gmacchia@rm.unicatt.it [Department of Radiation Oncology, Fondazione di Ricercae Cura ' Giovanni Paolo II,' Universita Cattolica del S. Cuore, Campobasso (Italy); Ferrandina, Gabriella [Department of Gynecologic Oncology, Fondazione di Ricercae Cura ' Giovanni Paolo II,' Universita Cattolica del S. Cuore, Campobasso (Italy); Bonomo, Pierluigi; Deodato, Francesco; Massaccesi, Mariangela [Department of Radiation Oncology, Fondazione di Ricercae Cura ' Giovanni Paolo II,' Universita Cattolica del S. Cuore, Campobasso (Italy); Mignogna, Samantha; Tambaro, Rosa [Department of Palliative Therapies, Fondazione di Ricercae Cura ' Giovanni Paolo II,' Universita Cattolica del S. Cuore, Campobasso (Italy); Rossi, Marco [Department of Anaesthesia, Intensive Care, and Pain Medicine, Fondazione di Ricercae Cura ' Giovanni Paolo II,' Universita Cattolica del S. Cuore, Campobasso (Italy); Flocco, Mariano [' Madre Teresa di Calcutta' Hospice, Larino (Italy); Scapati, Andrea [Department of Radiation Oncology, ' San Francesco' Hospital, Nuoro (Italy); and others

    2012-08-01

    Purpose: To define the maximum tolerated dose of a conformal short-course accelerated radiotherapy in patients with symptomatic advanced pelvic cancer. Methods and Materials: A phase I trial in 3 dose-escalation steps was designed: 14 Gy (3.5-Gy fractions), 16 Gy (4-Gy fractions), and 18 Gy (4.5-Gy fractions). The eligibility criteria included locally advanced and/or metastatic pelvic cancer and Eastern Cooperative Oncology Group performance status of {<=}3. Treatment was delivered in 2 days with twice-daily fractionation and at least an 8-hour interval. Patients were treated in cohorts of 6-12 to define the maximum tolerated dose. The dose-limiting toxicity was defined as any acute toxicity of grade 3 or greater, using the Radiation Therapy Oncology Group scale. Pain was recorded using a visual analog scale. The effect on quality of life was evaluated according to Cancer Linear Analog Scale (CLAS). Results: Of the 27 enrolled patients, 11 were male and 16 were female, with a median age of 72 years (range 47-86). The primary tumor sites were gynecologic (48%), colorectal (33.5%), and genitourinary (18.5%). The most frequent baseline symptoms were bleeding (48%) and pain (33%). Only grade 1-2 acute toxicities were recorded. No patients experienced dose-limiting toxicity. With a median follow-up time of 6 months (range 3-28), no late toxicities were observed. The overall (complete plus partial) symptom remission was 88.9% (95% confidence interval 66.0%-97.8%). Five patients (41.7%) had complete pain relief, and six (50%) showed >30% visual analog scale reduction. The overall response rate for pain was 91.67% (95% confidence interval 52.4%-99.9%). Conclusions: Conformal short course radiotherapy in twice-daily fractions for 2 consecutive days was well tolerated up to a total dose of 18 Gy. A phase II study is ongoing to confirm the efficacy on symptom control and quality of life indexes.

  15. Development and Dosimetric Characterization of a Tissue Substitute (Bolus) For Use in Linear Accelerator Electron Radiotherapy

    Science.gov (United States)

    Estrada Trujillo, Jorge; Villaseñor Navarro, Luis Felipe; Mitsoura, Eleni

    2003-09-01

    We propose the design of a new custom made material, to be used as a tissue substitute in external beam electron radiotherapy, based on cotton fabric and beeswax. Due to its inexpensive, easy preparation, constant thickness, flexibility, uniform density and physical properties similar to those of soft tissue, this bolus will insure personalized optimal dose build up and dose distribution in irregular treatment regions. Materials and Methods: We used commercial Campeche beeswax and 100% cotton fabric to prepare the bolus. Beeswax's physical characteristics were determined by thermal and density analysis. Its chemical properties are to be determined by electronic microcopy. We performed quality control tests and calibration of the Varian 2100C linear accelerator. The tissue equivalence of the material is established for a range of electron energies (6, 9, 12, 16, 20 MeV) using a water equivalent solid phantom (PTW; Freiburg, Germany) and a plane parallel ionization chamber (PTW) associated to a PTW electrometer. Results: Beeswax's absolute density was found to be 0.9181g/ml at 21°C, with a melting point of 45°C. For the bolus elaboration, the cotton fabric was soaked in liquid beeswax and thin sheets of approximately 1 mm were obtained. These presented high flexibility, physical stability (color, texture, thickness) and homogeneity. Determination of this dosimetric characteristics and equivalent thickness are still in process. Discussion and conclusions: Our preliminary results suggest that the tissue substitute is easily made, inexpensive to produce, molds well to the treatment area and its positioning is easy and reproducible over the course of the treatment. So we consider that it's a good alternative to the commercial bolus.

  16. Hart et le positivisme postmoderne en droit international

    NARCIS (Netherlands)

    J. d' Aspremont

    2009-01-01

    This article argues that, in the context of international law, Hart can really be considered a post-modern positivist. Hart has not only refined the source thesis of Hobbes, Bentham and Austin by shedding the command-based understanding of law. Hart has also overcome the difficulties of Kelsen’s hyp

  17. Output trends, characteristics, and measurements of three megavoltage radiotherapy linear accelerators.

    Science.gov (United States)

    Hossain, Murshed

    2014-07-08

    The purpose of this study is to characterize and understand the long-term behavior of the output from megavoltage radiotherapy linear accelerators. Output trends of nine beams from three linear accelerators over a period of more than three years are reported and analyzed. Output, taken during daily warm-up, forms the basis of this study. The output is measured using devices having ion chambers. These are not calibrated by accredited dosimetry laboratory, but are baseline-compared against monthly output which is measured using calibrated ion chambers. We consider the output from the daily check devices as it is, and sometimes normalized it by the actual output measured during the monthly calibration of the linacs. The data show noisy quasi-periodic behavior. The output variation, if normalized by monthly measured "real' output, is bounded between ± 3%. Beams of different energies from the same linac are correlated with a correlation coefficient as high as 0.97, for one particular linac, and as low as 0.44 for another. These maximum and minimum correlations drop to 0.78 and 0.25 when daily output is normalized by the monthly measurements. These results suggest that the origin of these correlations is both the linacs and the daily output check devices. Beams from different linacs, independent of their energies, have lower correlation coefficient, with a maximum of about 0.50 and a minimum of almost zero. The maximum correlation drops to almost zero if the output is normalized by the monthly measured output. Some scatter plots of pairs of beam output from the same linac show band-like structures. These structures are blurred when the output is normalized by the monthly calibrated output. Fourier decomposition of the quasi-periodic output is consistent with a 1/f power law. The output variation appears to come from a distorted normal distribution with a mean of slightly greater than unity. The quasi-periodic behavior is manifested in the seasonally averaged output

  18. Results on accelerator production of innovative radionuclides for metabolic radiotherapy and PET and on related nuclear data

    Energy Technology Data Exchange (ETDEWEB)

    Groppi, Flavia [LASA, Radiochemistry Laboratory, Universita degli Studi di Milano and INFN-Milano, via F.lli Cervi 201, I-20090 Segrate, Milan (Italy)]. E-mail: Flavia.Groppi@mi.infn.it; Bonardi, Mauro L. [LASA, Radiochemistry Laboratory, Universita degli Studi di Milano and INFN-Milano, via F.lli Cervi 201, I-20090 Segrate, Milan (Italy); Menapace, Enzo [ENEA, Division for Advanced Physics Technologies, Via Don Fiammelli 2, I-40128 Bologna (Italy); Morzenti, Sabrina [LASA, Radiochemistry Laboratory, Universita degli Studi di Milano and INFN-Milano, via F.lli Cervi 201, I-20090 Segrate, Milan (Italy); Zona, Cristiano [LASA, Radiochemistry Laboratory, Universita degli Studi di Milano and INFN-Milano, via F.lli Cervi 201, I-20090 Segrate, Milan (Italy); Canella, Lea [LASA, Radiochemistry Laboratory, Universita degli Studi di Milano and INFN-Milano, via F.lli Cervi 201, I-20090 Segrate, Milan (Italy); Alfassi, Zeev B. [Department Nuclear Engineering, Ben Gurion University, Beer Sheva (Israel)

    2006-06-23

    A range of high specific activity accelerator-produced radionuclides in no-carrier-added (NCA) form, for uses in metabolic radiotherapy and for PET, has been investigated. To this aim it was necessary optimizing the irradiation parameters by determining the excitation functions of the nuclear reactions involved, as needed for the following selective radiochemical separations of the radionuclides of interest. For the NCA radionuclides investigated, the spectrometry measurements, done at LASA-INFN on {gamma}, X and on {alpha} spectra are discussed together with the measurements of radionuclidic, radiochemical and chemical purities by analytical and radioanalytical techniques.

  19. Maarten’t Hart bestaat niet

    Directory of Open Access Journals (Sweden)

    H. Werhnan

    1992-05-01

    Full Text Available Maarten 't Hart werd in 1944 geboren in het Nederlandse stadje Maasshuis. Daar spelen verscheidene van zijn autobiografische romans, een teken dat hij verknocht is aan zijn geboortegrond. In zijn eerste romans Stenen voor een ransuil (1971 en Ik had een wapenbroeder (1973 staat het thema van de homoseksualiteit centraal. In zijn latere werk spelen de liefde tussen man en vrouw en de liefde voor de natuur en de muziek een grote rol. Veel van zijn werk, vooral zijn beroemdste roman Een vlucht regenwulpen, staat in het teken van de gewenste eenzaamheid. Behalve zeventien romans en verhalenbundels (de meest recente roman Onder de korenmaat verscheen in 1991 publiceerde Maarten 't Hart een tienlal boeken met populair-welenschappelijke studies en essays. In Ratten (1973 gaat het over zijn voorliefde voor een gediscrimineerd dier, in De som van misverstanden (1978 beschrijfl hij zijn liefde voor de literatuur, in De vrouw bestaat niel trekt hij len strijde tegen het feminisme en in Een dasspeld uit Toela (1990 rekent hij af met de literatuurcritici. Maarten't Hart is een uitnemend en gevoelig verteller Waarschijnlijk is het aan zijn nogal slordige stijl en zijn afkeer van het experiment in de romankunst te wijten dal hij na de Multatuliprijs-1975 voor zijn verhalenbundel Het vrome volk (1974 geen enkele lileraire prijs meer heeft gekregen. Wei halen zijn boeken hoge oplagen en is hij ereburger van Maasshuis.

  20. Targeted Alpha Therapy: The US DOE Tri-Lab (ORNL, BNL, LANL) Research Effort to Provide Accelerator-Produced 225Ac for Radiotherapy

    Science.gov (United States)

    John, Kevin

    2017-01-01

    Targeted radiotherapy is an emerging discipline of cancer therapy that exploits the biochemical differences between normal cells and cancer cells to selectively deliver a lethal dose of radiation to cancer cells, while leaving healthy cells relatively unperturbed. A broad overview of targeted alpha therapy including isotope production methods, and associated isotope production facility needs, will be provided. A more general overview of the US Department of Energy Isotope Program's Tri-Lab (ORNL, BNL, LANL) Research Effort to Provide Accelerator-Produced 225Ac for Radiotherapy will also be presented focusing on the accelerator-production of 225Ac and final product isolation methodologies for medical applications.

  1. Evolution of Hypofractionated Accelerated Radiotherapy for Prostate Cancer – The Sunnybrook Experience

    Directory of Open Access Journals (Sweden)

    Hima Bindu Musunuru

    2014-11-01

    Full Text Available Stereotactic Ablative Body Radiotherapy (SABR is a newer method of ultra hypo fractionated radiotherapy that uses combination of image guided radiotherapy (IGRT and intensity modulated radiotherapy(IMRT or volumetric modulated arc therapy(VMAT, to deliver high doses of radiation in a few fractions to a target, at the same time sparing the surrounding organs at risk(OAR.SABR is ideal for treating small volumes of disease and has been introduced in a number of disease sites including brain, lung, liver, spine and prostate. Given the radiobiological advantages of treating prostate cancer with high doses per fraction, SABR is becoming a standard of care for low and intermediate risk prostate cancer patients based upon the results from Sunny Brook and also the US-based prostate SABR consortium. This review examines the development of moderate and ultra hypo fractionation schedules at the Odette Cancer centre, Sunnybrook Health Sciences. Moderate hypo fractionation protocol was first developed in 2001 for intermediate risk prostate cancer and from there on different treatment schedules including SABR evolved for all risk groups.

  2. Accelerated partial breast irradiation with external beam radiotherapy. First results of the German phase 2 trial

    Energy Technology Data Exchange (ETDEWEB)

    Ott, Oliver J.; Strnad, Vratislav; Stillkrieg, Wilhelm; Fietkau, Rainer [University Hospital Erlangen, Department of Radiation Oncology, Erlangen (Germany); Uter, Wolfgang [University Erlangen-Nuremberg, Dept. of Medical Informatics, Biometry and Epidemiology, Erlangen (Germany); Beckmann, Matthias W. [University Hospital Erlangen, Dept. of Gynecology, Erlangen (Germany)

    2017-01-15

    To evaluate the feasibility and efficacy of external beam three-dimensional (3D) conformal accelerated partial breast irradiation (APBI) for selected patients with early breast cancer. Between 2011 and 2016, 72 patients were recruited for this prospective phase 2 trial. Patients were eligible for APBI if they had histologically confirmed breast cancer or pure ductal carcinoma in situ (DCIS), a tumor diameter ≤3 cm, clear resection margins ≥2 mm, no axillary lymph node involvement, no distant metastases, tumor bed clips, and were aged ≥50 years. Patients were excluded if mammography showed a multicentric invasive growth pattern, or if they had residual diffuse microcalcifications postoperatively, an extensive intraductal component, or vessel invasion. Patients received 3D conformal external beam APBI with a total dose of 38 Gy in 10 fractions in 1-2 weeks. The trial had been registered at the German Clinical Trials Register, DRKS-ID: DRKS00004417. Median follow-up was 25.5 months (range 1-61 months). Local control was maintained in 71 of 72 patients. The 3-year local recurrence rate was 2.1% (95% confidence interval, CI: 0-6.1%). Early toxicity (grade 1 radiodermatitis) was seen in 34.7% (25/72). Late side effects ≥ grade 3 did not occur. Cosmetic results were rated as excellent/good in 96.7% (59/61). APBI with external beam radiotherapy techniques is feasible with low toxicity and, according to the results of the present and other studies, on the way to becoming a standard treatment option for a selected subgroup of patients. (orig.) [German] Untersuchung der Vertraeglichkeit und Sicherheit der externen, 3-D-konformalen akzelerierten Teilbrustbestrahlung (APBI) fuer ausgewaehlte Patientinnen mit einem fruehen Mammakarzinom. Von 2011 bis 2016 wurden 72 Patientinnen in diese prospektive Phase-2-Studie eingebracht. Einschlusskriterien waren ein histologisch gesichertes Mammakarzinom oder DCIS, ein Tumordurchmesser ≤ 3 cm, tumorfreie Resektionsraender ≥ 2

  3. Prospective randomized trial to compare accelerated (six fractions a week radiotherapy against concurrent chemoradiotherapy (using conventional fractionation in locally advanced head and neck cancers

    Directory of Open Access Journals (Sweden)

    Manoj Gupta

    2015-01-01

    Full Text Available Background: Concurrent chemoradiation (CCRT is currently considered to be the standard of care in locally advanced head and neck cancer. The optimum radiotherapy schedule for best local control and acceptable toxicity is not yet clear. We aimed at shortening of treatment time by using accelerated radiation, thereby comparing the disease response, loco-regional tumor control and tolerability of accelerated radiation (six fractions per week against CCRT in locally advanced head and neck cancer. Materials and Methods: We conducted the prospective randomized study for a period of 2 years from June 2011 to May 2013 in 133 untreated patients of histologically confirmed squamous cell carcinoma of head and neck. Study group (66 patients received accelerated radiotherapy with 6 fractions per week (66Gy/33#/5½ weeks. Control group (67 patients received CCRT with 5 fractions per week radiation (66 Gy/33#/6½ weeks along with intravenous cisplatin 30 mg/m 2 weekly. Tumor control, survival, acute and late toxicities were assessed. Results: Median overall treatment time was 38 days and 45 days in the accelerated radiotherapy and concurrent chemoradiation arm, respectively. At a median follow up of 12 months, 41 patients (62.1% in the accelerated radiotherapy arm and 47 patients (70.1% in the CCRT arm were disease free (P = 0.402. Local disease control was comparable in both the arms. Acute toxicities were significantly higher in the CCRT arm as compared with accelerated radiotherapy arm. There was no difference in late toxicities between the two arms. Conclusion: We can achieve, same or near to the same local control, with lower toxicities with accelerated six fractions per week radiation compared with CCRT especially for Indian population.

  4. The Nano-X Linear Accelerator: A Compact and Economical Cancer Radiotherapy System Incorporating Patient Rotation.

    Science.gov (United States)

    Eslick, Enid M; Keall, Paul J

    2015-10-01

    Rapid technological improvements in radiotherapy delivery results in improved outcomes to patients, yet current commercial systems with these technologies on board are costly. The aim of this study was to develop a state-of-the-art cancer radiotherapy system that is economical and space efficient fitting with current world demands. The Nano-X system is a compact design that is light weight combining a patient rotation system with a vertical 6 MV fixed beam. In this paper, we present the Nano-X system design configuration, an estimate of the system dimensions and its potential impact on shielding cost reductions. We provide an assessment of implementing such a radiotherapy system clinically, its advantages and disadvantages compared to a compact conventional gantry rotating linac. The Nano-X system has several differentiating features from current radiotherapy systems, it is [1] compact and therefore can fit into small vaults, [2] light weight, and [3] engineering efficient, i.e., it rotates a relatively light component and the main treatment delivery components are not under rotation (e.g., DMLCs). All these features can have an impact on reducing the costs of the system. In terms of shielding requirements, leakage radiation was found to be the dominant contributor to the Nano-X vault and as such no primary shielding was necessary. For a low leakage design, the Nano-X vault footprint and concrete volume required is 17 m2 and 35 m3 respectively, compared to 54 m2 and 102 m3 for a conventional compact linac vault, resulting in decreased costs in shielding. Key issues to be investigated in future work are the possible patient comfort concerns associated with the patient rotation system, as well as the magnitude of deformation and subsequent adaptation requirements.

  5. Positivismo e Obediência em Herbert Hart / Positivism and obedience in Herbert Hart

    Directory of Open Access Journals (Sweden)

    Luana Renostro Heinen

    2010-12-01

    Full Text Available O tema do respeito à legalidade sempre serviu como ponto de acusação aos adversários do Positivismo Jurídico. O presente artigo objetiva investigar o tema da obediência às leis no pensamento do Herbert Hart, um dos juristas mais importantes do século XX, filiado à corrente denominada de Positivismo Jurídico. Veremos como Hart desenvolve uma sofisticada argumentação visando manter a separação entre direito e moral, característica diferenciadora do Positivismo Jurídico, respondendo assim às críticas de que tal correntereferendaria ordens jurídicas marcadas por situações de flagrante injustiça.AbstractThe issue of respect for legality has always served as a point of complaint to the opponents of legal positivism. This articleaims to investigate the theme of obedience to the laws in the thinking of Herbert Hart, one of the most important jurists of the twentieth century, affiliated to the current called legal positivism.We’ll see how Hart developed a sophisticated argumentation in order to maintain the separation between law and morality, distinguishingcharacteristic of legal positivism, responding to critics that say that such current would ratify legal orders marked by situationsof injustice.

  6. Hyperfractionated or accelerated radiotherapy in head and neck cancer: a meta-analysis

    DEFF Research Database (Denmark)

    Bourhis, J.; Overgaard, Jens; Audry, H.

    2006-01-01

    -specified categories: hyperfractionated, accelerated, and accelerated with total dose reduction. FINDINGS: 15 trials with 6515 patients were included. The median follow-up was 6 years. Tumours sites were mostly oropharynx and larynx; 5221 (74%) patients had stage III-IV disease (International Union Against Cancer...

  7. Technologies of image guidance and the development of advanced linear accelerator systems for radiotherapy.

    Science.gov (United States)

    Wu, Vincent W C; Law, Maria Y Y; Star-Lack, Josh; Cheung, Fion W K; Ling, C Clifton

    2011-01-01

    As advanced radiotherapy approaches for targeting the tumor and sparing the normal tissues have been developed, the image guidance of therapy has become essential to directing and confirming treatment accuracy. To approach these goals, image guidance devices now include kV on-board imagers, kV/MV cone-beam CT systems, CT-on-rails, and mobile and in-room radiographic/fluoroscopic systems. Nonionizing sources, such as ultrasound and optical systems, and electromagnetic devices have been introduced to monitor or track the patient and/or tumor positions during treatment. In addition, devices have been designed specifically for monitoring and/or controlling respiratory motion. Optimally, image-guided radiation therapy systems should possess 3 essential elements: (1) 3D imaging of soft tissues and tumors, (2) efficient acquisition and comparison of the 3D images, and (3) an efficacious process for clinically meaningful intervention. Understanding and using these tools effectively is central to current radiotherapy practice. The implementation and integration of these devices continue to carry practical challenges, which emphasize the need for further development of the technologies and their clinical applications.

  8. Implementation of intraoperative radiotherapy in a linear accelerator Varian 21EX; Implementacao da radioterapia intraoperatoria em um acelerador linear VARIAN 21EX

    Energy Technology Data Exchange (ETDEWEB)

    Piriz, Gustavo H.; Lozano, Enrique; Banguero, Yolma; Varon, Carlos Fernando; Mancilla, Claudio S. [Instituto Nacional del Cancer, Santiago (Chile). Radioterapia; Parra, Cristian [Universidad de la Frontera, Temuco (Chile); Pacheco, P. [Universidad Nacional Mayor de San Marcos, Lima (Peru)

    2011-07-01

    The aim of this paper is to present the experience on intraoperative radiotherapy, which has as the reference center the network of radiotherapy in Chile. It is detailed the construction of a system of applicators with an easy coupling on a linear accelerator collimator. It is also detailed the cost and the measurements set up with their corresponding percentage depth dose and isodose curves. This technique was implemented in a Varian Clinac 21EX for beams with 6, 9 and 12 MeV electron energy. The coupling system provides a good dose distribution both laterally and in depth for different energies. This provides a good coverage of treatment planning volume. (author)

  9. Laser-driven particle acceleration for radiobiology and radiotherapy: where we are and where we are going

    Science.gov (United States)

    Giulietti, Antonio

    2017-05-01

    Radiation therapy of tumors progresses continuously and so do devices, sharing a global market of about $ 4 billions, growing at an annual rate exceeding 5%. Most of the progress involves tumor targeting, multi-beam irradiation, reduction of damage on healthy tissues and critical organs, dose fractioning. This fast-evolving scenario is the moving benchmark for the progress of the laser-based accelerators towards clinical uses. As for electrons, both energy and dose requested by radiotherapy are available with plasma accelerators driven by lasers in the power range of tens of TW but several issues have still to be faced before getting a prototype device for clinical tests. They include capability of varying electron energy, stability of the process, reliability for medical users. On the other side hadron therapy, presently applied to a small fraction of cases but within an exponential growth, is a primary option for the future. With such a strong motivation, research on laser-based proton/ion acceleration has been supported in the last decade in order to get performances suitable to clinical standards. None of these performances has been achieved so far with laser techniques. In the meantime a rich crop of data have been obtained in radiobiological experiments performed with beams of particles produced with laser techniques. It is quite significant however that most of the experiments have been performed moving bio samples to laser labs, rather moving laser equipment to bio labs or clinical contexts. This give us the measure that laser community cannot so far provide practical devices usable by non-laser people.

  10. Continuous hyperfractionated accelerated radiotherapy with/without mitomycin C in head and neck cancer

    NARCIS (Netherlands)

    Dobrowsky, W; Naude, J; Widder, J; Dobrowsky, E; Millesi, W; Pavelka, R; Grasl, C; Reichel, M

    1998-01-01

    Purpose: To evaluate the effect of mitomycin C to an accelerated hyperfractionated radiation therapy. The aim was to test a very short schedule with/without mitomycin C (MMC) with conventional fractionation in histologically verified squamous cell carinoma of the head and neck region. Methods and Ma

  11. GPU-accelerated automatic identification of robust beam setups for proton and carbon-ion radiotherapy

    Science.gov (United States)

    Ammazzalorso, F.; Bednarz, T.; Jelen, U.

    2014-03-01

    We demonstrate acceleration on graphic processing units (GPU) of automatic identification of robust particle therapy beam setups, minimizing negative dosimetric effects of Bragg peak displacement caused by treatment-time patient positioning errors. Our particle therapy research toolkit, RobuR, was extended with OpenCL support and used to implement calculation on GPU of the Port Homogeneity Index, a metric scoring irradiation port robustness through analysis of tissue density patterns prior to dose optimization and computation. Results were benchmarked against an independent native CPU implementation. Numerical results were in agreement between the GPU implementation and native CPU implementation. For 10 skull base cases, the GPU-accelerated implementation was employed to select beam setups for proton and carbon ion treatment plans, which proved to be dosimetrically robust, when recomputed in presence of various simulated positioning errors. From the point of view of performance, average running time on the GPU decreased by at least one order of magnitude compared to the CPU, rendering the GPU-accelerated analysis a feasible step in a clinical treatment planning interactive session. In conclusion, selection of robust particle therapy beam setups can be effectively accelerated on a GPU and become an unintrusive part of the particle therapy treatment planning workflow. Additionally, the speed gain opens new usage scenarios, like interactive analysis manipulation (e.g. constraining of some setup) and re-execution. Finally, through OpenCL portable parallelism, the new implementation is suitable also for CPU-only use, taking advantage of multiple cores, and can potentially exploit types of accelerators other than GPUs.

  12. Accelerated partial breast irradiation using 3D conformal radiotherapy: initial clinical experience

    Energy Technology Data Exchange (ETDEWEB)

    Gatti, M.; Madeddu, A.; Malinverni, G.; Delmastro, E.; Bona, C.; Gabriele, P. [IRCC-Radiotherapy, Candiolo, TO (Italy); Baiotto, B.; Stasi, M. [IRCC-Medical Physics, Candiolo, TO (Italy); Ponzone, R.; Siatis, D. [IRCC-Surgery, Candiolo, TO (Italy)

    2006-11-15

    Accelerated partial breast irradiation using 3D-C.R.T. is technically sophisticate but feasible and acute toxicity to date has been minimal. A C.T.V.-to-P.T.V. margin of 10 mm seems to provide coverage for analyzed patients. However, more patients and additional studies will be needed to validate the accuracy of this margin, and longer follow-up will be needed to assess acute and chronic toxicity, tumor control, and cosmetic results. (author)

  13. Fractionated stereotactic radiotherapy with linear accelerator for uveal melanoma - preliminary Vienna results

    Energy Technology Data Exchange (ETDEWEB)

    Zehetmayer, M.; Ruhswurm, I.; Georgopoulos, M. [Dept. of Ophthalmology, Vienna Univ. (Austria); Dieckmann, K.; Kren, G.; Poetter, R. [Dept. of Radiotherapy and Radiobiology, Vienna Univ (Austria); Kitz, K. [Dept. of Neurosurgery, Vienna Univ. (Austria)

    1999-06-01

    Between June 1997 and February 1998, 21 patients suffering from uveal melanomas have been treated with a sterotactic 6 MeV LINAC (Saturne 43 {sup trademark}, General Electric, France) in conjunction with a stereotactic frame system (BrainLAB {sup trademark}, Germany). Immobilization of the eye was ensured with an optical fixation system which was proven reliable. During radiotherapy, movements of the irradiated eye were controlled on a monitor and documented by video recording. All patients co-operated very well with the optical fixation system. In 1164 measurements, the median value of horizontal deviation of the diseased eye during treatment was 0.3 mm (range: 0 to 1.3 mm). Median vertical deviation was 0.2 mm (range: 0 to 1.2 mm). For all patients, mean tumor prominence before treatment was 6.0{+-}2.2 mm. In 20 patients, the total dose of 70 Gy (at 80%) was delivered in 5 fractions within 10 days. In one patient with a ciliary body tumor, the total dose of 70 Gy was divided into 7 fractions for better sparing of the anterior eye segment. Results: After a follow-up of at least 6 months, local tumor control was seen in all eyes. Mean tumor thickness reduction after 3, 6 and 9 months was 7%, 13% and 31%, respectively. Up to now, only mild subacute side-effects located in the anterior eye segment have been noticed. (orig.)

  14. Image guided, adaptive, accelerated, high dose brachytherapy as model for advanced small volume radiotherapy.

    Science.gov (United States)

    Haie-Meder, Christine; Siebert, Frank-André; Pötter, Richard

    2011-09-01

    Brachytherapy has consistently provided a very conformal radiation therapy modality. Over the last two decades this has been associated with significant improvements in imaging for brachytherapy applications (prostate, gynecology), resulting in many positive advances in treatment planning, application techniques and clinical outcome. This is emphasized by the increased use of brachytherapy in Europe with gynecology as continuous basis and prostate and breast as more recently growing fields. Image guidance enables exact knowledge of the applicator together with improved visualization of tumor and target volumes as well as of organs at risk providing the basis for very individualized 3D and 4D treatment planning. In this commentary the most important recent developments in prostate, gynecological and breast brachytherapy are reviewed, with a focus on European recent and current research aiming at the definition of areas for important future research. Moreover the positive impact of GEC-ESTRO recommendations and the highlights of brachytherapy physics are discussed what altogether presents a full overview of modern image guided brachytherapy. An overview is finally provided on past and current international brachytherapy publications focusing on "Radiotherapy and Oncology". These data show tremendous increase in almost all research areas over the last three decades strongly influenced recently by translational research in regard to imaging and technology. In order to provide high level clinical evidence for future brachytherapy practice the strong need for comprehensive prospective clinical research addressing brachytherapy issues is high-lighted. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  15. Accelerated radiotherapy with concomitant boost technique (69.5 Gy/5 weeks). An alternative in the treatment of locally advanced head and neck cancer

    Energy Technology Data Exchange (ETDEWEB)

    Kubes, Jiri; Vondracek, Vladimir; Pala, Miloslav [Prague Univ., Prag (Czech Republic). Inst. of Radiation Oncology; Cvek, Jakub; Feltl, David [Faculty Hospital Ostrava (Czech Republic). Dept. of Oncology

    2011-10-15

    To present the feasibility and results of accelerated radiotherapy with concomitant boost technique (69.5 Gy/5 weeks) in the treatment of locally advanced head and neck cancer. A total of 65 patients were treated between June 2006 and August 2009. The distribution of clinical stages was as follows: II 11%, III 23%, IV 61%, and not defined 5%. The median follow-up was 30.5 months. The treatment plan was completed in 94% of patients. Patients were treated using the conformal or intensity-modulated radiotherapy (IMRT) technique. The median overall treatment time was 37 days (13-45 days). The mean radiotherapy dose was 68.4 Gy (16-74 Gy). Overall survival was 69% after 2 years. Disease-free survival was 62% after 2 years. Acute toxicity {>=} grade 3(RTOG scale) included mucositis (grade 3: 42.6%), pharynx (grade 3: 42.3%), skin (grade 3: 9.5%), larynx (grade 3: 4%), while late toxicity affected skin (grade 3: 6.25%) and salivary glands (grade 3: 3.7%). Accelerated radiotherapy with concomitant boost technique is feasible in patients with locally advanced head and neck cancer, has an acceptable toxicity profile, and yields promising treatment results.

  16. Accelerated split-course radiotherapy and concomitant cis-platinum and 5-fluorouracil chemotherapy with folinic acid enhancement in unresectable head and neck cancer

    Energy Technology Data Exchange (ETDEWEB)

    Wendt, T.G.; Wustrow, T.P.U.; Hartenstein, R.C.; Trott, K.R.

    1988-01-01

    In patients suffering from locally advanced, unresectable squamous cell carcinoma (SCC) of the base of the tongue, the floor of the mouth, the mobile part of the tongue, the tonsils, the hypopharynx and the larynx radiotherapy yields poor results, due to local failure rather than to distant metastases. Since toxicity of radiotherapy and cytotoxic chemotherapy do not overlap entirely efforts were made to achieve better results combining these two treatment modalities. Clinical trials on simultaneous radiotherapy/chemotherapy focussed on two cytotoxic agents: Cis-dichlorodiammineplatinum(II) (cis-DDP) and 5-flourouracil (5-FU). Another approach to overcome the radioresistance of large SCC adopts accelerated fractionation. The potential tumor doubling time of sqamous cell carcinomas is about four days, and thus repopulation of surviving clonogenic tumor cells during fractionated radiotherapy may be the cause of poor treatment results. In this pilot study a twice daily fractionated split-course radiotherapy is combined with simultaneous administration of cis-DDP and 5-FU with folinic acid (FA) enhancement.

  17. Monte Carlo Simulation of a Linear Accelerator and Electron Beam Parameters Used in Radiotherapy

    Directory of Open Access Journals (Sweden)

    Mohammad Taghi Bahreyni Toossi

    2009-06-01

    Full Text Available Introduction: In recent decades, several Monte Carlo codes have been introduced for research and medical applications. These methods provide both accurate and detailed calculation of particle transport from linear accelerators. The main drawback of Monte Carlo techniques is the extremely long computing time that is required in order to obtain a dose distribution with good statistical accuracy. Material and Methods: In this study, the MCNP-4C Monte Carlo code was used to simulate the electron beams generated by a Neptun 10 PC linear accelerator. The depth dose curves and related parameters to depth dose and beam profiles were calculated for 6, 8 and 10 MeV electron beams with different field sizes and these data were compared with the corresponding measured values. The actual dosimetry was performed by employing a Welhofer-Scanditronix dose scanning system, semiconductor detectors and ionization chambers. Results: The result showed good agreement (better than 2% between calculated and measured depth doses and lateral dose profiles for all energies in different field sizes. Also good agreements were achieved between calculated and measured related electron beam parameters such as E0, Rq, Rp and R50. Conclusion: The simulated model of the linac developed in this study is capable of computing electron beam data in a water phantom for different field sizes and the resulting data can be used to predict the dose distributions in other complex geometries.

  18. Sheldon-Hart - Invasive Species Inventory, Monitoring, and Control

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Beginning in 2009/2010, the Sheldon/Hart Refuge Complex refocused efforts to inventory, monitor, and control invasive plant species to allow for better adaptive...

  19. Sheldon-Hart - Control of Invasive Horses & Burros

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Monitoring, repair, and replacement of fences along the exterior boundaries of Hart Mountain NAR and Sheldon NWR to prevent future invasion and re-population of...

  20. Hart Mountain Wilderness : Summary report and preliminary recommendations

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is a summarized report on the Hart Mountain Wilderness area. Topics covered include the area's history, its resources, management and development of...

  1. Accelerated hypofractionated adjuvant whole breast radiotherapy with concomitant photon boost after conserving surgery for early stage breast cancer: a prospective evaluation on 463 patients.

    Science.gov (United States)

    Cante, Domenico; Rosa La Porta, Maria; Casanova-Borca, Valeria; Sciacero, Piera; Girelli, Giuseppe; Pasquino, Massimo; Franco, Pierfrancesco; Ozzello, Franca

    2011-01-01

    The current standard therapeutic option for early stage breast cancer (EBC) employs a multimodality treatment approach including conservative surgery, radiotherapy, chemotherapy, and hormone therapy. The most common adjuvant radiotherapeutic strategy consists of external beam radiation therapy (EBRT) delivered to the whole breast using 1.8-2 Gy fractions given five times a week, up to a total dose of 45-50 Gy over a period of 5 weeks. In recent years, altered schedules employing larger dose per fraction delivered in fewer treatment sessions over a shorter overall treatment time began to be explored. We herein present clinical data on accelerated hypofractionated adjuvant whole-breast radiotherapy delivered on a daily basis for a total treatment time of 20 fractions. Between February 2005 and June 2009, a total of 463 patients underwent hypofractionated accelerated adjuvant radiation after conservative surgery for early breast cancer (pathological stage pTis, pT1 or pT2, pN0-N1). The basic course of radiotherapy consisted of 45 Gy, to the whole breast in 20 fractions with 2.25 Gy/fraction; an additional daily boost dose of 0.25 Gy was concomitantly delivered, to the lumpectomy cavity, for an additional total dose of 5 Gy. The cumulative nominal dose was 50 Gy. At follow-up, patients were examined at 3 and 6 months after the end of radiotherapy and twice a year afterward. Toxicity was scored according to the Common Terminology Criteria for Adverse Events, using the Radiation Therapy Oncology Group /European Organization for Research and Treatment of Cancer toxicity scale. Cosmetic results were assessed in agreement with the Harvard criteria. All the 463 patients treated with the accelerated hypofractionated adjuvant whole-breast radiotherapy schedule achieved at least 6 months' follow-up and subsequently were considered for the present analysis. With a median follow-up of 27 months, 5-year DFS is 93.1%. Only three patients experienced disease recurrence: two of them

  2. TLD Intercomparison in accelerators for radiotherapy in three Latin american countries; Intercomparacion TLD en aceleradores para radioterapia en tres paises latinoamericanos

    Energy Technology Data Exchange (ETDEWEB)

    Gaona, E.; Azorin N, J.; Perez, M.A.; Picon, C.; Castellanos, E.; Plazas, M.C.; Murcia, G.; Archundia, L. [Depto. El Hombre y su Ambiente. Universidad Autonoma Metropolitana, Calz. Del Hueso 1100, 04960 Mexico D.F. (Mexico)

    1998-12-31

    In Radiotherapy one of the objectives is to establish and to give follow up to quality assurance programs which make sure that the doses administered to the patients with cancer are a high probability of a success in external radiation. Likewise, one of the present preoccupations of the United Nations Agencies as well as the International Atomic Energy Agency and the Pan-American Health Organization is the optimal employment of the radiations in the treatment of cancer patients since the administered dose in Radiotherapy suffers considerable variations by the lack of quality assurance programs. The use of Electron linear accelerators requires a program of quality assurance that includes expert personnel, equipment and adequate facilities. The more used methodology for the dosimetry calibration and characterization of X-ray beams and high energy electrons for radiotherapy use is using a ionization chamber dosemeter calibrated in a regional secondary standardization laboratory. However, to establish and give follow up to the quality assurance programs it is necessary the dosimetric intercomparison through TLD. In this study it was designed plastic phantoms with TLD crystals and it was made its characterization to realize an absorbed dose analysis in the crystals exposed at X-ray beams 6 MV and high energy electrons 10 and 12 MeV to standardize the dosimetric procedures and proceeding to realize an International Pilot intercomparison of absorbed doses in TLD crystals in three Latin American countries: Mexico, Peru and Colombia with the participation of accelerators of five different institutions. The found results show that the majority of the measured doses with TLD in the different accelerators were in the 0.95-1.05 range though it had two cases outside of this range. The use of the phantoms with TLD crystals shows that they are of excellent aid to make analysis of the doses administered to the patients and an intercomparison of results to standardize procedures at

  3. Accelerated gradient-based free form deformable registration for online adaptive radiotherapy

    Science.gov (United States)

    Yu, Gang; Liang, Yueqiang; Yang, Guanyu; Shu, Huazhong; Li, Baosheng; Yin, Yong; Li, Dengwang

    2015-04-01

    The registration of planning fan-beam computed tomography (FBCT) and daily cone-beam CT (CBCT) is a crucial step in adaptive radiation therapy. The current intensity-based registration algorithms, such as Demons, may fail when they are used to register FBCT and CBCT, because the CT numbers in CBCT cannot exactly correspond to the electron densities. In this paper, we investigated the effects of CBCT intensity inaccuracy on the registration accuracy and developed an accurate gradient-based free form deformation algorithm (GFFD). GFFD distinguishes itself from other free form deformable registration algorithms by (a) measuring the similarity using the 3D gradient vector fields to avoid the effect of inconsistent intensities between the two modalities; (b) accommodating image sampling anisotropy using the local polynomial approximation-intersection of confidence intervals (LPA-ICI) algorithm to ensure a smooth and continuous displacement field; and (c) introducing a ‘bi-directional’ force along with an adaptive force strength adjustment to accelerate the convergence process. It is expected that such a strategy can decrease the effect of the inconsistent intensities between the two modalities, thus improving the registration accuracy and robustness. Moreover, for clinical application, the algorithm was implemented by graphics processing units (GPU) through OpenCL framework. The registration time of the GFFD algorithm for each set of CT data ranges from 8 to 13 s. The applications of on-line adaptive image-guided radiation therapy, including auto-propagation of contours, aperture-optimization and dose volume histogram (DVH) in the course of radiation therapy were also studied by in-house-developed software.

  4. Accelerated hypofractionated radiotherapy as adjuvant regimen after conserving surgery for early breast cancer: interim report of toxicity after a minimum follow up of 3 years

    Directory of Open Access Journals (Sweden)

    Marucci Laura

    2010-01-01

    Full Text Available Abstract Background Accelerated hypofractionation is an attractive approach for adjuvant whole breast radiotherapy. In this study we evaluated the adverse effects at least 3 years post an accelerated hypofractionated whole breast radiotherapy schedule. Methods From October 2004 to March 2006, 39 consecutive patients aged over 18 years with pTis, pT1-2, pN0-1 breast adenocarcinoma who underwent conservative surgery were treated with an adjuvant accelerated hypofractionated radiotherapy schedule consisting of 34 Gy in 10 daily fractions over 2 weeks to the whole breast, followed after 1 week by an electron boost dose of 8 Gy in a single fraction to the tumour bed. Skin and lung radiation toxicity was evaluated daily during therapy, once a week for one month after radiotherapy completion, every 3 months for the first year and from then on every six months. In particular lung toxicity was investigated in terms of CT density evaluation, pulmonary functional tests, and clinical and radiological scoring. Paired t-test, Chi-square test and non-parametric Wilcoxon test were performed. Results After a median follow-up of 43 months (range 36-52 months, all the patients are alive and disease-free. None of the patients showed any clinical signs of lung toxicity, no CT-lung toxicity was denoted by radiologist on CT lung images acquired about 1 year post-radiotherapy, no variation of pulmonary density evaluated in terms of normalised Hounsfield numbers was evident. Barely palpable increased density of the treated breast was noted in 9 out of 39 patients (in 2 patients this toxicity was limited to the boost area and teleangectasia (2 limited to the boost area was evident in 2 out of 39 patients. The compliance with the treatment was excellent (100%. Conclusion The radiotherapy schedule investigated in this study (i.e 34 Gy in 3.4 Gy/fr plus boost dose of 8 Gy in single fraction is a feasible and safe treatment and does not lead to adjunctive acute and late

  5. Study of the characteristics of neutron monitor area applied to the evaluation of dose rates in a 15 MeV radiotherapy accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, Candido M. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Inst. de Fisica]. E-mail: candido_1998@yahoo.com; Patrao, Karla C.S.; Pereira, Walsan W.; Fonseca, Evaldo S.; Giannoni, Ricardo A. [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil). Lab. de Neutrons]. E-mails: karla@ird.gov.br; walsan@ird.gov.br; Batista, Delano V.S. [Instituto Nacional do Cancer (INCa), Rio de Janeiro, RJ (Brazil). Setor de Fisica Medica]. E-mail: delano@inca.gov.br

    2007-07-01

    Currently, in Radiotherapy, the use of linear accelerators is becoming each time more common. From Radiation Protection point of view, these instruments represent an advance in relation to the cobalt and caesium irradiators, mainly due to absence of the radioactive material. On the other hand, accelerators with the energies superior to 10 MeV produce contamination of the therapeutic beam with the presence of neutrons generated in the interaction of high-energy photons with high atomic number materials from the own irradiator. The present work carries through measurements in a linear accelerator of 15 MeV using three neutron area monitors for a comparison of the response of these instruments, evaluating its adequacy to this measurement. Characteristics of use and operation associates to parameters such as: monitor dead time, monitor gamma rejection, and calibration results are also analyzed in this study. (author)

  6. SU-E-T-275: Radiobiological Evaluation of Intensity Modulated Radiotherapy Treatment for Locally Advanced Head and Neck Squamous Cell Carcinomas

    Energy Technology Data Exchange (ETDEWEB)

    Rekha Reddy, B.; Ravikumar, M.; Tanvir Pasha, C.R; Anil Kumar, M.R; Varatharaj, C. [Kidwai Memorial Institute of Oncology Bangalore, Karnataka (India); Pyakuryal, A [University Illinois at Chicago, Chicago, IL (United States); Narayanasamy, Ganesh [UTHSCSA, San Antonio, TX (United States)

    2014-06-01

    Purpose: To evaluate the radiobiological outcome of Intensity Modulated Radiotherapy Treatment (IMRT) for locally advanced head and neck squamous cell carcinomas using HART (Histogram Analysis in Radiation Therapy; J Appl Clin Med Phys 11(1): 137–157, 2010) program and compare with the clinical outcomes. Methods: We have treated 20 patients of stage III and IV HNSCC Oropharynx and hypopharynx with accelerated IMRT technique and concurrent chemotherapy. Delineation of tumor and normal tissues were done using Danish Head and Neck Cancer Group (DAHANCA) contouring guidelines and radiotherapy was delivered to a dose of 70Gy in 35 fractions to the primary and involved lymph nodes, 63Gy to intermediate risk areas and 56 Gy to lower risk areas, Monday to Saturday, 6 Days/week using 6 MV Photons with an expected overall treatment time of 6 weeks. The TCP and NTCP's were calculated from the dose-volume histogram (DVH) statistics using the Poisson Statistics (PS) and JT Lyman models respectively and the Resultwas correlated with clinical outcomes of the patients with mean follow up of 24 months. Results: Using HART program, the TCP (0.89± 0.01) of primary tumor and the NTCP for parotids (0.20±0.12), spinal cord (0.05±0.01), esophagus (0.30±0.2), mandible (0.35±0.21), Oral cavity (0.37±0.18), Larynx (0.30±0.15) were estimated and correlated with clinical outcome of the patients. Conclusion: Accelerated IMRT with Chemotherapy is a clinical feasible option in the treatment of locally advanced HNSCC with encouraging initial tumour response and acceptable acute toxicities. The correlation between the clinical outcomes and radiobiological model estimated parameters using HART programs are found to be satisfactory.

  7. The influence of HPV-associated p16-expression on accelerated fractionated radiotherapy in head and neck cancer: evaluation of the randomised DAHANCA 6&7 trial

    DEFF Research Database (Denmark)

    Lassen, Pernille; Eriksen, Jesper G; Krogdahl, Annelise

    2011-01-01

    demonstrated in the randomised DAHANCA 6&7 trial. We aimed to assess the influence of tumour HPV-status, expressed by p16, on the response to accelerated fractionated radiotherapy in HNSCC through evaluation of the DAHANCA 6&7 trial. MATERIALS AND METHODS: Immunohistochemical detection of HPV-associated p16......-expression was performed on FFPE-pre-treatment tumour-tissues from 794 patients enrolled in the DAHANCA 6&7 trial. The influence of tumour p16-status on loco-regional tumour control and survival as a function of fractionation schedule (5Fx/week vs 6Fx/week) was evaluated 5years after the completion...... of radiotherapy. RESULTS: The significant and independent prognostic value of tumour p16-positivity in HNSCC radiotherapy was confirmed, with adjusted hazard ratios (HR) of 0.58 [0.43-0.78], 0.47 [0.33-0.67] and 0.54 [0.42-0.68] for loco-regional control, disease-specific and overall survival, respectively...

  8. The influence of HPV-associated p16-expression on accelerated fractionated radiotherapy in head and neck cancer: Evaluation of the randomised DAHANCA 6&7 trial

    DEFF Research Database (Denmark)

    Lassen, Pernille; Eriksen, Jesper Grau; Krogdahl, Annelise

    2011-01-01

    demonstrated in the randomised DAHANCA 6&7 trial. We aimed to assess the influence of tumour HPV-status, expressed by p16, on the response to accelerated fractionated radiotherapy in HNSCC through evaluation of the DAHANCA 6&7 trial. MATERIALS AND METHODS: Immunohistochemical detection of HPV-associated p16......-expression was performed on FFPE-pre-treatment tumour-tissues from 794 patients enrolled in the DAHANCA 6&7 trial. The influence of tumour p16-status on loco-regional tumour control and survival as a function of fractionation schedule (5Fx/week vs 6Fx/week) was evaluated 5years after the completion...... of radiotherapy. RESULTS: The significant and independent prognostic value of tumour p16-positivity in HNSCC radiotherapy was confirmed, with adjusted hazard ratios (HR) of 0.58 [0.43-0.78], 0.47 [0.33-0.67] and 0.54 [0.42-0.68] for loco-regional control, disease-specific and overall survival, respectively...

  9. Development of an ultrasmall C-band linear accelerator guide for a four-dimensional image-guided radiotherapy system with a gimbaled x-ray head.

    Science.gov (United States)

    Kamino, Yuichiro; Miura, Sadao; Kokubo, Masaki; Yamashita, Ichiro; Hirai, Etsuro; Hiraoka, Masahiro; Ishikawa, Junzo

    2007-05-01

    We are developing a four-dimensional image-guided radiotherapy system with a gimbaled x-ray head. It is capable of pursuing irradiation and delivering irradiation precisely with the help of an agile moving x-ray head on the gimbals. Requirements for the accelerator guide were established, system design was developed, and detailed design was conducted. An accelerator guide was manufactured and basic beam performance and leakage radiation from the accelerator guide were evaluated at a low pulse repetition rate. The accelerator guide including the electron gun is 38 cm long and weighs about 10 kg. The length of the accelerating structure is 24.4 cm. The accelerating structure is a standing wave type and is composed of the axial-coupled injector section and the side-coupled acceleration cavity section. The injector section is composed of one prebuncher cavity, one buncher cavity, one side-coupled half cavity, and two axial coupling cavities. The acceleration cavity section is composed of eight side-coupled nose reentrant cavities and eight coupling cavities. The electron gun is a diode-type gun with a cerium hexaboride (CeB6) direct heating cathode. The accelerator guide can be operated without any magnetic focusing device. Output beam current was 75 mA with a transmission efficiency of 58%, and the average energy was 5.24 MeV. Beam energy was distributed from 4.95 to 5.6 MeV. The beam profile, measured 88 mm from the beam output hole on the axis of the accelerator guide, was 0.7 mm X 0.9 mm full width at half maximum (FWHM) width. The beam loading line was 5.925 (MeV)-Ib (mA) X 0.00808 (MeV/mA), where Ib is output beam current. The maximum radiation leakage of the accelerator guide at 100 cm from the axis of the accelerator guide was calculated as 0.33 cGy/min at the rated x-ray output of 500 cGy/min from the measured value. This leakage requires no radiation shielding for the accelerator guide itself per IEC 60601-2-1.

  10. Application study of wind power technology to the city of Hart, Michigan

    Energy Technology Data Exchange (ETDEWEB)

    Asmussen, J.; Fisher, P.D.; Park, G.L.; Krauss, O.

    1975-12-31

    Information is presented concerning wind data collections and analysis; Hart power demand and consumer usage; wind power assessment; hydro power assessment; results of preliminary economics analysis; environmental impact of wind turbines and operation in the Hart, Oceana County, Michigan area; and systems model for the Hart power system with wind turbine. (DCC)

  11. Hyperfractionated accelerated radiotherapy with concomitant integrated boost of 70-75 Gy in 5 weeks for advanced head and neck cancer. A phase I dose escalation study

    Energy Technology Data Exchange (ETDEWEB)

    Cvek, J.; Skacelikova, E.; Otahal, B.; Halamka, M.; Feltl, D. [University Hospital Ostrava (Czech Republic). Dept. of Oncology; Kubes, J. [University Hospital Bulovka, Prague (Czech Republic). Dept. of Radiation Oncology; Kominek, P. [University Hospital Ostrava (Czech Republic). Dept. of Otolaryngology

    2012-08-15

    Background and purpose: The present study was performed to evaluate the feasibility of a new, 5-week regimen of 70-75 Gy hyperfractionated accelerated radiotherapy with concomitant integrated boost (HARTCIB) for locally advanced, inoperable head and neck cancer. Methods and materials: A total of 39 patients with very advanced, stage IV nonmetastatic head and neck squamous cell carcinoma (median gross tumor volume 72 ml) were included in this phase I dose escalation study. A total of 50 fractions intensity-modulated radiotherapy (IMRT) were administered twice daily over 5 weeks. Prescribed total dose/dose per fraction for planning target volume (PTV{sub tumor}) were 70 Gy in 1.4 Gy fractions, 72.5 Gy in 1.45 Gy fractions, and 75 Gy in 1.5 Gy fractions for 10, 13, and 16 patients, respectively. Uninvolved lymphatic nodes (PTV{sub uninvolved}) were irradiated with 55 Gy in 1.1 Gy fractions using the concomitant integrated boost. Results: Acute toxicity was evaluated according to the RTOG/EORTC scale; the incidence of grade 3 mucositis was 51% in the oral cavity/pharynx and 0% in skin and the recovery time was {<=} 9 weeks for all patients. Late toxicity was evaluated in patients in complete remission according to the RTOG/EORTC scale. No grade 3/4 late toxicity was observed. The 1-year locoregional progression-free survival was 50% and overall survival was 55%. Conclusion: HARTCIB (75 Gy in 5 weeks) is feasible for patients deemed unsuitable for chemoradiation. Acute toxicity was lower than predicted from radiobiological models; duration of dysphagia and confluent mucositis were particularly short. Better conformity of radiotherapy allows the use of more intensive altered fractionation schedules compared with older studies. These results suggest that further dose escalation might be possible when highly conformal techniques (e.g., stereotactic radiotherapy) are used.

  12. Advances in conformal radiotherapy using Monte Carlo Code to design new IMRT and IORT accelerators and interpret CT numbers

    CERN Document Server

    Wysocka-Rabin, A

    2013-01-01

    The introductory chapter of this monograph, which follows this Preface, provides an overview of radiotherapy and treatment planning. The main chapters that follow describe in detail three significant aspects of radiotherapy on which the author has focused her research efforts. Chapter 2 presents studies the author worked on at the German National Cancer Institute (DKFZ) in Heidelberg. These studies applied the Monte Carlo technique to investigate the feasibility of performing Intensity Modulated Radiotherapy (IMRT) by scanning with a narrow photon beam. This approach represents an alternative to techniques that generate beam modulation by absorption, such as MLC, individually-manufactured compensators, and special tomotherapy modulators. The technical realization of this concept required investigation of the influence of various design parameters on the final small photon beam. The photon beam to be scanned should have a diameter of approximately 5 mm at Source Surface Distance (SSD) distance, and the penumbr...

  13. Image-guided radiotherapy by in-room CT- linear accelerator combination; Radiotherapie guidee par tomodensitometrie associee a l'accelerateur lineaire dans la salle de traitement

    Energy Technology Data Exchange (ETDEWEB)

    Crevoisiera, R. de; Lefkopoulos, D. [Institut Gustave-Roussy, Dept. de Radiotherapie, 94 - Villejuif (France); Kuban, D. [Texas Univ., M.D. Anderson Cancer Center, Dept. of Radiation Oncology, Houston, Texas (United States)

    2006-09-15

    Target localization has become increasingly important in the advent of IMRT, as treatment margins are reduced and target doses are increased with high-dose gradients outside this target volume. The in-room CT on rails-LINAC system allows CT imaging while the patient remains immobilized in the treatment position just prior to treatment. The anatomic inter- and intra-fractional variations can be therefore quantified during a course of treatment. The position of the tumour can be checked and corrected before the fraction. In case of modification of tumour shape, a re-planning of the treatment is also feasible. However, several issues remain: the integration with routine clinical treatment due to a lack of software tools, the frequency of imaging, and the cost-efficiency ratio. The clinical experience is yet very limited but CT-image-guided radiotherapy appears promising for prostate, brain and spinal tumours. (authors)

  14. Hart Schaffner Marx看欧美品牌的长效发展%Hart Schaffner Marx Over 1O0 Years of Brand Leadership

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    @@ Hart Schaffner Marx公司品牌家族中,最成功的品牌是始创于1887年的Hart Schaffner Marx.Hart Schaffner Marx是世界上历史最悠久的成功服饰品牌之一. Hart Schaffner Marx是当之无愧美国正装第一品牌,年零售额达5亿美金,占据了美国男装市场50%的销售份额.

  15. The influence of epidermal growth factor receptor and tumor differentiation on the response to accelerated radiotherapy of squamous cell carcinomas of the head and neck in the randomized DAHANCA 6 and 7 study

    DEFF Research Database (Denmark)

    Eriksen, Jesper Grau; Steiniche, Torben; Overgaard, Jens

    2005-01-01

    to the repopulation taking place during radiotherapy. The aim of the current study was to address the influence of EGFr and histopathological differentiation when the overall treatment time of radiotherapy was moderately reduced. PATIENTS AND METHODS: Eight hundred and three patients with representative pretreatment...... tissue samples from the randomized DAHANCA 6 and 7 study of 5 vs. 6 fx/wk of radiotherapy. EGFr was visualized using immunohistochemistry and separated into high and low expression before correlation with clinical data. RESULTS: Tumors with high EGFr (84%) responded better to moderately accelerated...... radiotherapy, than carcinomas with low EGFr, using locoregional control as endpoint and a similar pattern was seen, stratifying by well/moderate vs. poor tumor differentiation. Therefore, a combined parameter was constructed showing a more prominent separation of response: tumors with high EGFr and well/moderate...

  16. Breast cancer radiotherapy: controversies and prospectives

    Institute of Scientific and Technical Information of China (English)

    YU Jin-ming; WANG Yong-sheng

    2008-01-01

    @@ Despite consensus on breast cancer radiotherapy, there are still some controversies over post-mastectomy radiotherapy (PMRT) in patients with 1-3 positive lymph nodes, accelerated partial breast irradiation (APBI), appropriate sequence of radiotherapy, chemotherapy and hormonal treatment, and radiotherapy after preoperative systemic therapy.

  17. Gradient of γ rays and β particles irradiation’s energy produced by accelerator and its use in radiotherapy of cancer diseases

    Energy Technology Data Exchange (ETDEWEB)

    Kastrati, Labinot, E-mail: labinotkastrati82@gmail.com; Nafezi, Gazmend, E-mail: gazmend-nafezi@hotmail.com [Department of Physics, Faculty of Mathematical and Natural Sciences, University of Prishtina “HasanPrishtina”, Prishtina, Kosovo (Country Unknown); Shehi, Gëzim, E-mail: gezimshehi@yahoo.com [Department of Physics, Faculty of Mathematical and Natural Sciences, University of Tirana, Tirana (Albania)

    2016-03-25

    The Ionising irradiations used mostly in the treatment of tumoral diseases are: X, γ, β and e irradiations. The discussion will be about radiations, produced in accelerators, with photon energy 6 MV and 15 MV and electron energy from 5 MeV to 15 MeV. Due to the differences between γ and β radiations, their absorbtion in living tissues will be different. It is important to know, the absorption performance before and after the electronic equilibrium. For these purposes, we’ve use the function of dose gradient, for irradiations γ and β. It represents the velocity of dose change as a function of depth in tissue. From skin to maximum dose value, the increase of G-function is more accentuated for γ-rays than for β-particles, while after that the G-function decreasing is less sharp for γ-rays, while for β-particles, it is almost promptly. This fact allow us to use in radiotherapy, not only γ-rays but β-particles, too. The lasts, represents, a much more efficient tool, especially in terms of radiation protection, of health adjacent tissues and organs. Finally, we’ll to discus, about the advantages in terms of radiation protection of both, γ-rays and β-particles used in radiotherapy.

  18. Commissioning and quality assurance of the X-ray volume Imaging system of an image-guided radiotherapy capable linear accelerator

    Directory of Open Access Journals (Sweden)

    Muralidhar K

    2008-01-01

    Full Text Available An Image-Guided Radiotherapy-capable linear accelerator (Elekta Synergy was installed at our hospital, which is equipped with a kV x-ray volume imaging (XVI system and electronic portal imaging device (iViewGT. The objective of this presentation is to describe the results of commissioning measurements carried out on the XVI facility to verify the manufacturer′s specifications and also to evolve a QA schedule which can be used to test its performance routinely. The QA program consists of a series of tests (safety features, geometric accuracy, and image quality. These tests were found to be useful to assess the performance of the XVI system and also proved that XVI system is very suitable for image-guided high-precision radiation therapy.

  19. Acute Toxicity Profile and Compliance to Accelerated Radiotherapy Plus Carbogen and Nicotinamide for Clinical Stage T2-4 Laryngeal Cancer: Results of a Phase III Randomized Trial

    Energy Technology Data Exchange (ETDEWEB)

    Janssens, Geert O., E-mail: g.janssens@rther.umcn.nl [Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Terhaard, Chris H. [Department of Radiation Oncology, University Medical Center Utrecht, Utrecht (Netherlands); Doornaert, Patricia A. [Department of Radiation Oncology, VU University Medical Center, Amsterdam (Netherlands); Bijl, Hendrik P. [Department of Radiation Oncology, University Medical Center Groningen, Groningen (Netherlands); Ende, Piet van den [Department of Radiation Oncology, Maastricht University Medical Centre, Maastricht (Netherlands); Chin, Alim [Department of Clinical Oncology, Leiden University Medical Centre, Leiden (Netherlands); Pop, Lucas A.; Kaanders, Johannes H. [Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands)

    2012-02-01

    Purpose: To report the acute toxicity profile and compliance from a randomized Phase III trial comparing accelerated radiotherapy (AR) with accelerated radiotherapy plus carbogen and nicotinamide (ARCON) in laryngeal cancer. Methods and Materials: From April 2001 to February 2008, 345 patients with cT2-4 squamous cell laryngeal cancer were randomized to AR (n = 174) and ARCON (n = 171). Acute toxicity was scored weekly until Week 8 and every 2-4 weeks thereafter. Compliance to carbogen and nicotinamide was reported. Results: Between both treatment arms (AR vs. ARCON) no statistically significant difference was observed for incidence of acute skin reactions (moist desquamation: 56% vs. 58%, p = 0.80), acute mucosal reactions (confluent mucositis: 79% vs. 85%, p = 0.14), and symptoms related to acute mucositis (severe pain on swallowing: 53% vs. 58%, p = 0.37; nasogastric tube feeding: 28% vs. 28%, p = 0.98; narcotic medicines required: 58% vs. 58%, p = 0.97). There was a statistically significant difference in median duration of confluent mucositis in favor of AR (2.0 vs 3.0 weeks, p = 0.01). There was full compliance with carbogen breathing and nicotinamide in 86% and 80% of the patients, with discontinuation in 6% and 12%, respectively. Adjustment of antiemesis prophylaxis was needed in 42% of patients. Conclusion: With the exception of a slight increase in median duration of acute confluent mucositis, the present data reveal a similar acute toxicity profile between both regimens and a good compliance with ARCON for clinical stage T2-4 laryngeal cancers. Treatment outcome and late morbidity will determine the real therapeutic benefit.

  20. Acute toxicity profile and compliance to accelerated radiotherapy plus carbogen and nicotinamide for clinical stage T2-4 laryngeal cancer: results of a phase III randomized trial.

    Science.gov (United States)

    Janssens, Geert O; Terhaard, Chris H; Doornaert, Patricia A; Bijl, Hendrik P; van den Ende, Piet; Chin, Alim; Pop, Lucas A; Kaanders, Johannes H

    2012-02-01

    To report the acute toxicity profile and compliance from a randomized Phase III trial comparing accelerated radiotherapy (AR) with accelerated radiotherapy plus carbogen and nicotinamide (ARCON) in laryngeal cancer. From April 2001 to February 2008, 345 patients with cT2-4 squamous cell laryngeal cancer were randomized to AR (n = 174) and ARCON (n = 171). Acute toxicity was scored weekly until Week 8 and every 2-4 weeks thereafter. Compliance to carbogen and nicotinamide was reported. Between both treatment arms (AR vs. ARCON) no statistically significant difference was observed for incidence of acute skin reactions (moist desquamation: 56% vs. 58%, p = 0.80), acute mucosal reactions (confluent mucositis: 79% vs. 85%, p = 0.14), and symptoms related to acute mucositis (severe pain on swallowing: 53% vs. 58%, p = 0.37; nasogastric tube feeding: 28% vs. 28%, p = 0.98; narcotic medicines required: 58% vs. 58%, p = 0.97). There was a statistically significant difference in median duration of confluent mucositis in favor of AR (2.0 vs 3.0 weeks, p = 0.01). There was full compliance with carbogen breathing and nicotinamide in 86% and 80% of the patients, with discontinuation in 6% and 12%, respectively. Adjustment of antiemesis prophylaxis was needed in 42% of patients. With the exception of a slight increase in median duration of acute confluent mucositis, the present data reveal a similar acute toxicity profile between both regimens and a good compliance with ARCON for clinical stage T2-4 laryngeal cancers. Treatment outcome and late morbidity will determine the real therapeutic benefit. Copyright © 2012 Elsevier Inc. All rights reserved.

  1. Implementation of a linear mini accelerator for radiotherapy intraoperative; Puesta en marcha de un miniacelerador lineal para radioterapia intraoperatoria

    Energy Technology Data Exchange (ETDEWEB)

    Macias-Verde, D.; Yanez-Lopez, D.; Marti-Asenjo, J.; Sanchez-Carrascal, M.; Torres-Pozas, S.; Godoy-Cazorla, J. I.; Madan-Rodriguez, C.; Martin-Oliva, R.

    2013-07-01

    Has been defined the status initial reference of the lineal mini-accelerator Intrabeam PRS 500. The alternative worksheet in times of treatment provides an additional verification. The system is validated for clinical use. (Author)

  2. Procedure to measure the neutrons spectrum around a lineal accelerator for radiotherapy; Procedimiento para medir el espectro de los neutrones en torno a un acelerador lineal para radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Vega C, H. R.; Hernandez D, V. M.; Letechipia de L, C. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98060 Zacatecas (Mexico); Benites R, J. L. [Servicios de Salud de Nayarit, Centro Estatal de Cancerologia, Calzada de la Cruz 116 Sur, 63000 Tepic, Nayarit (Mexico); Salas L, M. A., E-mail: fermineutron@yahoo.com [Universidad Autonoma de Zacatecas, Unidad Academica de Agronomia, Apdo. Postal 336, 98000 Zacatecas (Mexico)

    2013-10-15

    An experimental procedure was developed, by means of Bonner spheres, to measure the neutrons spectrum around Linacs of medical use that only requires of a single shot of the accelerator; to this procedure we denominate Planetary or Isocentric method. One of the problems associated to the neutrons spectrum measurement in a radiotherapy room with lineal accelerator is because inside the room a mixed, intense and pulsed radiation field takes place affecting the detection systems based on active detector; this situation is solved using a passive detector. In the case of the Bonner spheres spectrometer the active detector has been substituted by activation detectors, trace detectors or thermoluminescent dosimeters. This spectrometer uses several spheres that are situated one at a time in the measurement point, this way to have the complete measurements group the accelerator should be operated, under the same conditions, so many times like spheres have the spectrometer, this activity can consume a long time and in occasions due to the work load of Linac to complicate the measurement process too. The procedure developed in this work consisted on to situate all the spectrometer spheres at the same time and to make the reading by means of a single shot, to be able to apply this procedure, is necessary that before the measurements two characteristics are evaluated: the cross-talking of the spheres and the symmetry conditions of the neutron field. This method has been applied to determine the photo-neutrons spectrum produced by a lineal accelerator of medical use Varian ix of 15 MV to 100 cm of the isocenter located to 5 cm of depth of a solid water mannequin of 30 x 30 x 15 cm. The spectrum was used to determine the total flow and the environmental dose equivalent. (Author)

  3. Reflections on Public Health: Captain Hart and Malaria

    Centers for Disease Control (CDC) Podcasts

    2006-10-01

    This podcast consists of segments of an interview conducted by Capt. Kathleen McDuffie, CDC, with Capt. Russell Hart, a 100 year old retired sanitary engineer of the U.S. Public Health Service Commissioned Corps as he reflects on his work in malaria control. The interview was conducted in 2006.  Created: 10/1/2006 by Coordinating Center for Health Information and Service (CCHIS), National Center for Health Marketing (NCHM).   Date Released: 1/7/2009.

  4. Reflections on Public Health: Captain Hart and Sanitation

    Centers for Disease Control (CDC) Podcasts

    2006-10-01

    This podcast consists of segments of an interview conducted by Capt. Kathleen McDuffie, CDC, with Capt. Russell Hart, a 100 year old retired sanitary engineer of the U.S. Public Health Service Commissioned Corps as he reflects on his work in environmental sanitation and the development of local health departments. The interview was conducted in 2006.  Created: 10/1/2006 by Coordinating Center for Health Information and Service (CCHIS), National Center for Health Marketing (NCHM).   Date Released: 1/7/2009.

  5. B. H. Liddell Hart; Theorist for the 21st Century

    Science.gov (United States)

    1986-05-20

    hiiting and guarding. The’man-in-the-dark’ had to seeK his enemy, find his way to a vulnerable spot, fix his foe in place, deliver a knock out blow, then...intimidation in response to his intervention in War Office affairs. His entitlemen+ to half-pay had two years more to run . it is small wonder that he would take...conscript army. The vital thread which runs throughout Liddell Hart’s early writings is the benefit to be gained from disruption. Disruption was the

  6. HLA Hart, Lon Fuller and the Ghosts of Legal Interpretation

    Directory of Open Access Journals (Sweden)

    Desmond Manderson

    2010-02-01

    Full Text Available Henry James’ short novel The Turn of the Screw appeared in 1898. It is a ghost story, uncanny both in content and in form. It relates such uneventful events that the reader is left turning from interpretation to interpretation, trying to determine just what is going on. Yet like the ghosts themselves, wherever we look, there is nothing to see. Until the very last sentence of the book, which hits one like a fist, nothing happens, nothing is proved, and yet a palpable feeling of tension and anxiety builds. It is therefore not fanciful to suggest that the real power of the story lies not in its narrative but in its rhetoric. The book creates a mood of anxiety that infects the reader’s reading. This is what one might call the ‘performative’ dimension of the story. James’ tale constitutes a reader, alert but confused, who thereby experiences the feeling of being part of a ghost story rather than merely reading about one. Sixty years later, HLA Hart and Lon Fuller likewise do not merely describe two different approaches to legal interpretation: in their style, rhetoric and structure they perform these approaches. This essay similarly wishes to connect its argument with its form and for this reason I have chosen to devote considerable space to discussing a work of literature. The Turn of the Screw illuminates certain essential features of the Hart/Fuller debate. Both are tales about law, interpretation, and ghosts. Through James, this essay argues that the debate between Hart and Fuller epitomizes legal interpretation as haunted. Rhetorically, they present two largely incommensurable visions of law. Yet their efforts to exclude the other’s approach fails. But instead of choosing between Hart and Fuller we can gain a richer understanding of legal interpretation if we treat their performance as mutual and interactive. I do not mean that Hart and Fuller can in any way be reconciled through compromise or synthesis. I mean rather that each

  7. Implementation of WirelessHART in the NS-2 Simulator and Validation of Its Correctness

    NARCIS (Netherlands)

    Zand, Pouria; Mathews, Emi; Havinga, Paul; Stojanovski, Spase; Sisinni, Emiliano; Ferrari, Paolo

    2014-01-01

    One of the first standards in the wireless sensor networks domain,WirelessHART (HART (Highway Addressable Remote Transducer)), was introduced to address industrial process automation and control requirements. This standard can be used as a reference point to evaluate other wireless protocols in the

  8. Determination of the neutron spectra in the treatment room of a linear accelerator for radiotherapy; Determinacion de los espectros de neutrones en la sala de tratamiento de un acelerador lineal para radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Vega C, H.R. [Universidad Autonoma de Zacatecas, Cuerpo Academico de Radiobiologia, A.P. 336, 98000 Zacatecas (Mexico); Barquero, R. [Hospital Universitario Rio Hortega, Valladolid (Spain); Mendez, R.; Iniguez, M.P. [Depto. de Fisica Teorica, Atomica, Molecular y Nuclear, Universidad de Valladolid, 47011 Valladolid (Spain)

    2003-07-01

    By means of a series of measures and Monte Carlo calculations the dosimetric characteristics of the photoneutrons have been determined that take place in volume to a linear accelerator of radiotherapy of 18 MV, LINAC, mark Siemens Mevatron model. The measures were carried out with thermoluminescent dosemeters TLD 600 and TLD 700 that were naked exposed and confined with cover of Cd and Sn, inside a sphere of paraffin and inside spheres Bonner. (Author)

  9. Photoneutron Flux Measurement via Neutron Activation Analysis in a Radiotherapy Bunker with an 18 MV Linear Accelerator

    Directory of Open Access Journals (Sweden)

    Çeçen Yiğit

    2017-01-01

    Full Text Available In cancer treatment, high energy X-rays are used which are produced by linear accelerators (LINACs. If the energy of these beams is over 8 MeV, photonuclear reactions occur between the bremsstrahlung photons and the metallic parts of the LINAC. As a result of these interactions, neutrons are also produced as secondary radiation products (γ,n which are called photoneutrons. The study aims to map the photoneutron flux distribution within the LINAC bunker via neutron activation analysis (NAA using indium-cadmium foils. Irradiations made at different gantry angles (0°, 90°, 180° and 270° with a total of 91 positions in the Philips SLI-25 linear accelerator treatment room and location-based distribution of thermal neutron flux was obtained. Gamma spectrum analysis was carried out with high purity germanium (HPGe detector. Results of the analysis showed that the maximum neutron flux in the room occurred at just above of the LINAC head (1.2x105 neutrons/cm2.s which is compatible with an americium-beryllium (Am-Be neutron source. There was a 90% decrease of flux at the walls and at the start of the maze with respect to the maximum neutron flux. And, just in front of the LINAC door, inside the room, neutron flux was measured less than 1% of the maximum.

  10. Be aware of neutrons outside short mazes from 10-MV linear accelerators X-rays in radiotherapy facilities.

    Science.gov (United States)

    Brockstedt, S; Holstein, H; Jakobsson, L; Tomaszewicz, A; Knöös, T

    2015-07-01

    During the radiation survey of a reinstalled 10-MV linear accelerator in an old radiation treatment facility, high dose rates of neutrons were observed. The area outside the maze entrance is used as a waiting room where patients, their relatives and staff other than those involved in the actual treatment can freely pass. High fluence rates of neutrons would cause an unnecessary high effective dose to the staff working in the vicinity of such a system, and it can be several orders higher than the doses received due to X-rays at the same location. However, the common knowledge appears to have been that the effect of neutrons at 10-MV X-ray linear accelerator facilities is negligible and shielding calculations models seldom mention neutrons for this operating energy level. Although data are scarce, reports regarding this phenomenon are now emerging. For the future, it is advocated that contributions from neutrons are considered already during the planning stage of new or modified facilities aimed for 10 MV and that estimated dose levels are verified.

  11. Implementation of WirelessHART in the NS-2 simulator and validation of its correctness.

    Science.gov (United States)

    Zand, Pouria; Mathews, Emi; Havinga, Paul; Stojanovski, Spase; Sisinni, Emiliano; Ferrari, Paolo

    2014-05-16

    One of the first standards in the wireless sensor networks domain,WirelessHART (HART (Highway Addressable Remote Transducer)), was introduced to address industrial process automation and control requirements. This standard can be used as a reference point to evaluate other wireless protocols in the domain of industrial monitoring and control. This makes it worthwhile to set up a reliable WirelessHART simulator in order to achieve that reference point in a relatively easy manner. Moreover, it offers an alternative to expensive testbeds for testing and evaluating the performance of WirelessHART. This paper explains our implementation of WirelessHART in the NS-2 network simulator. According to our knowledge, this is the first implementation that supports the WirelessHART network manager, as well as the whole stack (all OSI (Open Systems Interconnection model) layers) of the WirelessHART standard. It also explains our effort to validate the correctness of our implementation, namely through the validation of the implementation of the WirelessHART stack protocol and of the network manager. We use sniffed traffic from a real WirelessHART testbed installed in the Idrolab plant for these validations. This confirms the validity of our simulator. Empirical analysis shows that the simulated results are nearly comparable to the results obtained from real networks. We also demonstrate the versatility and usability of our implementation by providing some further evaluation results in diverse scenarios. For example, we evaluate the performance of the WirelessHART network by applying incremental interference in a multi-hop network.

  12. Implementation of WirelessHART in the NS-2 Simulator and Validation of Its Correctness

    Directory of Open Access Journals (Sweden)

    Pouria Zand

    2014-05-01

    Full Text Available One of the first standards in the wireless sensor networks domain,WirelessHART (HART (Highway Addressable Remote Transducer, was introduced to address industrial process automation and control requirements. This standard can be used as a reference point to evaluate other wireless protocols in the domain of industrial monitoring and control. This makes it worthwhile to set up a reliable WirelessHART simulator in order to achieve that reference point in a relatively easy manner. Moreover, it offers an alternative to expensive testbeds for testing and evaluating the performance of WirelessHART. This paper explains our implementation of WirelessHART in the NS-2 network simulator. According to our knowledge, this is the first implementation that supports the WirelessHART network manager, as well as the whole stack (all OSI (Open Systems Interconnection model layers of the WirelessHART standard. It also explains our effort to validate the correctness of our implementation, namely through the validation of the implementation of the WirelessHART stack protocol and of the network manager. We use sniffed traffic from a realWirelessHART testbed installed in the Idrolab plant for these validations. This confirms the validity of our simulator. Empirical analysis shows that the simulated results are nearly comparable to the results obtained from real networks. We also demonstrate the versatility and usability of our implementation by providing some further evaluation results in diverse scenarios. For example, we evaluate the performance of the WirelessHART network by applying incremental interference in a multi-hop network.

  13. SU-E-T-190: First Integration of Steriotactic Radiotherapy Planning System Iplan with Elekta Linear Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Biplab, S; Soumya, R; Paul, S; Jassal, K; Munshi, A; Giri, U; Kumar, V; Roy, S; Ganesh, T; Mohanti, B

    2014-06-01

    Purpose: For the first time in the world, BrainLAB has integrated its iPlan treatment planning system for clinical use with Elekta linear accelerator (Axesse with a Beam Modulator). The purpose of this study was to compare the calculated and measured doses with different chambers to establish the calculation accuracy of iPlan system. Methods: The iPlan has both Pencil beam (PB) and Monte Carlo (MC) calculation algorithms. Beam data include depth doses, profiles and output measurements for different field sizes. Collected data was verified by vendor and beam modelling was done. Further QA tests were carried out in our clinic. Dose calculation accuracy verified point, volumetric dose measurement using ion chambers of different volumes (0.01cc and 0.125cc). Planner dose verification was done using diode array. Plans were generated in iPlan and irradiated in Elekta Axesse linear accelerator. Results: Dose calculation accuracies verified using ion chamber for 6 and 10 MV beam were 3.5+/-0.33(PB), 1.7%+/-0.7(MC) and 3.9%+/-0.6(PB), 3.4%+/-0.6(MC) respectively. Using a pin point chamber, dose calculation accuracy for 6MV and 10MV was 3.8%+/-0.06(PB), 1.21%+/-0.2(MC) and 4.2%+/-0.6(PB), 3.1%+/-0.7(MC) respectively. The calculated planar dose distribution for 10.4×10.4 cm2 was verified using a diode array and the gamma analysis for 2%-2mm criteria yielded pass rates of 88 %(PB) and 98.8%(MC) respectively. 3mm-3% yields 100% passing for both MC and PB algorithm. Conclusion: Dose calculation accuracy was found to be within acceptable limits for MC for 6MV beam. PB for both beams and MC for 10 MV beam were found to be outside acceptable limits. The output measurements were done twice for conformation. The lower gamma matching was attributed to meager number of measured profiles (only two profiles for PB) and coarse measurement resolution for diagonal profile measurement (5mm). Based on these measurements we concluded that 6 MV MC algorithm is suitable for patient treatment.

  14. Accelerated partial breast irradiation with external beam three-dimensional conformal radiotherapy. Five-year results of a prospective phase II clinical study

    Energy Technology Data Exchange (ETDEWEB)

    Mozsa, Emoeke [National Institute of Oncology, Centre of Radiotherapy, Budapest (Hungary); Landesklinikum Wiener Neustadt, Department of Radiooncology and Radiotherapy, Wiener Neustadt (Austria); Meszaros, Norbert; Major, Tibor; Froehlich, Georgina; Stelczer, Gabor; Fodor, Janos; Polgar, Csaba [National Institute of Oncology, Centre of Radiotherapy, Budapest (Hungary); Sulyok, Zoltan [National Institute of Oncology, Centre of Surgery, Budapest (Hungary)

    2014-05-15

    The aim of this study was to report the 5-year results of accelerated partial breast irradiation (APBI) using external beam three-dimensional conformal radiotherapy (3D-CRT). Between 2006 and 2011, 44 patients with low-risk, stage I-II breast cancer underwent breast-conserving surgery. Postoperative APBI was given by means of 3D-CRT using three to five non-coplanar fields. The total dose of APBI was 36.9 Gy (nine fractions of 4.1 Gy b.i.d.). The mean follow-up time was 58.2 months for surviving patients. Survival results, side effects, and cosmetic results were assessed. One (2.3 %) local recurrence was observed, for a 5-year actuarial rate of 3.7 %. Neither regional nor distant failure was observed. Two patients died of internal disease. The 5-year disease-free, cancer-specific, and overall survival rates were 96.3, 100, and 95.1 %, respectively. Acute side effects included grade 1 (G1) erythema in 75 %, G1 parenchymal induration in 46 %, and G1 pain in 46 % of patients. No G2 or higher acute side effect occurred. Late side effects included G1, G2, and G3 fibrosis in 44, 7, and 2 % of patients, respectively, G1 skin pigmentation in 12 %, and G1 pain in 2 %. Asymptomatic fat necrosis occurred in 14 %. Cosmetic results were rated excellent or good in 86 % of cases by the patients themselves and 84 % by the physicians. The 5-year local tumor control, toxicity profile, and cosmetic results of APBI delivered with external beam 3D-CRT are encouraging and comparable to other APBI series. (orig.) [German] Evaluation der 5-Jahres-Ergebnisse bezueglich Ueberleben, Tumorkontrolle, Nebenwirkungen und Kosmetik nach Teilbrustbestrahlung (APBI) mittels 3-D-konformaler, akzelerierter Radiotherapie (3D-CRT). Zwischen 2006 und 2011 wurden 44 Patienten mit Brustkrebs im Stadium I-II und niedrigem Risikoprofil brusterhaltend operiert. Die adjuvante, 3-D-konformale APBI wurde mittels 3-5 nonkoplanarer Feldern durchgefuehrt. Die Gesamtdosis betrug 36,9 Gy bei 9 -mal 4,1 Gy b.i.d.. Nach

  15. Estimation of absorbed dose in clinical radiotherapy linear accelerator beams: Effect of ion chamber calibration and long-term stability.

    Science.gov (United States)

    Ravichandran, Ramamoorthy; Binukumar, Johnson Pichy; Davis, Cheriyathmanjiyil Antony

    2013-10-01

    The measured dose in water at reference point in phantom is a primary parameter for planning the treatment monitor units (MU); both in conventional and intensity modulated/image guided treatments. Traceability of dose accuracy therefore still depends mainly on the calibration factor of the ion chamber/dosimeter provided by the accredited Secondary Standard Dosimetry Laboratories (SSDLs), under International Atomic Energy Agency (IAEA) network of laboratories. The data related to Nd,water calibrations, thermoluminescent dosimetry (TLD) postal dose validation, inter-comparison of different dosimeter/electrometers, and validity of Nd,water calibrations obtained from different calibration laboratories were analyzed to find out the extent of accuracy achievable. Nd,w factors in Gray/Coulomb calibrated at IBA, GmBH, Germany showed a mean variation of about 0.2% increase per year in three Farmer chambers, in three subsequent calibrations. Another ion chamber calibrated in different accredited laboratory (PTW, Germany) showed consistent Nd,w for 9 years period. The Strontium-90 beta check source response indicated long-term stability of the ion chambers within 1% for three chambers. Results of IAEA postal TL "dose intercomparison" for three photon beams, 6 MV (two) and 15 MV (one), agreed well within our reported doses, with mean deviation of 0.03% (SD 0.87%) (n = 9). All the chamber/electrometer calibrated by a single SSDL realized absorbed doses in water within 0.13% standard deviations. However, about 1-2% differences in absorbed dose estimates observed when dosimeters calibrated from different calibration laboratories are compared in solid phantoms. Our data therefore imply that the dosimetry level maintained for clinical use of linear accelerator photon beams are within recommended levels of accuracy, and uncertainties are within reported values.

  16. A questão da racionalidade jurídica em Hart e em Dworkin

    OpenAIRE

    Carlos Ogawa Colontonio

    2011-01-01

    O objetivo desta pesquisa é apresentar o modelo racional jurídico elaborado por Hart e o modelo racional jurídico elaborado por Dworkin, assim como a crítica realizada por Dworkin em face do Conceito de Direito oferecido por Hart. O positivista, Herbert Hart, propõe que o direito é formado por um sistema de regras primárias e regras secundárias, sendo que uma regra de reconhecimento é responsável por identificar quais regras estão ou não incluídas em tal sistema. Caso seja apresentado um prob...

  17. Accelerated partial-breast irradiation vs conventional whole-breast radiotherapy in early breast cancer: A case-control study of disease control, cosmesis, and complications

    Directory of Open Access Journals (Sweden)

    Wadasadawala Tabassum

    2009-01-01

    Full Text Available Context: Accelerated partial-breast irradiation (APBI using various approaches is being increasingly employed for selected women with early breast cancer (EBC. Aims: To conduct a case-control study comparing disease control, cosmesis, and complications in patients with EBC undergoing APBI using multicatheter interstitial brachytherapy vs those receiving conventional whole breast radiotherapy (WBRT. Settings and Design: Women with EBC fulfilling the American Brachytherapy Society (ABS criteria were selected as ′cases′ if treated with APBI or as ′controls′ if offered WBRT during the period from May 2000 to December 2004. Materials and Methods: APBI patients were treated with high-dose-rate brachytherapy (HDR to a dose of 34 Gy/10#/6-8 days. WBRT was delivered to the whole breast to a dose of 45 Gy/25# followed by tumor bed boost, either with electrons (15 Gy/6# or interstitial brachytherapy (HDR 10 Gy/1#. Results: At the median follow-up of 43.05 months in APBI and 51.08 months in WBRT there was no difference in overall survival (OS, disease-free survival (DFS, late arm edema, and symptomatic fat necrosis between the two groups. However, APBI resulted in increase in mild breast fibrosis at the tumor bed. Telangiectasias were observed in three patients of the APBI group. The cosmetic outcome was significantly better in the APBI group as compared to the WBRT group (P = 0.003. Conclusions: This study revealed equivalent locoregional and distant disease control in the two groups. APBI offered better overall cosmetic outcome, though at the cost of a slight increase in mild breast fibrosis and telangiectasias.

  18. Accelerated hyperfractionated radiotherapy combined with induction and concomitant chemotherapy for inoperable non-small-cell lung cancer. Impact of total treatment time

    Energy Technology Data Exchange (ETDEWEB)

    Nyman, J.; Mercke, C. [Sahlgrenska Univ. Hospital, Gothenburg (Sweden). Dept. of Oncology; Bergman, B. [Sahlgrenska Univ. Hospital, Gothenburg (Sweden). Dept. of Respiratory Medicine

    1998-12-31

    Tumour cell proliferation during conventionally fractionated radiotherapy (RT) can negatively influence the treatment outcome in patients with unresectable non-small-cell lung cancer (NSCLC). Accelerated and hyperfractionated RT may therefore have an advantage over conventional RT. Moreover, earlier studies have suggested improved survival with addition of cisplatin-based chemotherapy (CT). We present here the results of combined treatment with induction and concomitant CT and accelerated hyperfractionated RT in a retrospective series of patients with advanced NSCLS. Between August 1990 and August 1995, 90 consecutive patients, aged 42-77 years (median 63 years), with locally advanced unresectable or medically inoperable NSCLC and good performance status were referred for treatment: stage: I 23%, IIIa 37%, IIIb 40%. Patient histologies included: squamous cell carcinoma 52%, adenocarcinoma 34% and large cell carcinoma 13%. The treatment consisted of two courses of CT (cisplatin 100 mg/m{sup 2} day 1 and etoposide 100 mg/m{sup 2} day 1-3 i.v.), the second course given concomitantly with RT. The total RT dose was 61.2-64.6 Gy, with two daily fractions of 1.7 Gy. A one-week interval was introduced after 40.8 Gy to reduce acute toxicity, making the total treatment time 4.5 weeks. Concerning toxicity, 33 patients had febrile neutropenia, 10 patients suffered from grade III oesophagitis and 7 patients had grade III pneumonitis. There were two possible treatment-related deaths, one due to myocardial infarction and the other due to a pneumocystis carinii infection. The 1-, 2- and 3-year overall survival rates were 72%, 46% and 34%, respectively; median survival was 21.3 months. Fifty-nine patients had progressive disease: 21 failed locoregionally, 29 had distant metastases and 9 patients had a combination of these. Pretreatment weight loss was the only prognostic factor found, except for stage. However, the results for stage IIIb were no different from those for stage IIIa

  19. Rapidly alternating combination of cisplatin-based chemotherapy and hyperfractionated accelerated radiotherapy in split course for Stage IIIA and Stage IIIB non-small cell lung cancer: results of a Phase I-II study by the GOTHA group

    Energy Technology Data Exchange (ETDEWEB)

    Alberto, P.; Mermillod, B. [Hopital Cantonal Geneve, Geneva (Switzerland); Mirimanoff, R.O.; Leyvraz, S.; Nagy-Mignotte, H.; Bolla, M.; Wellmann, D.; Moro, D.; Brambilla, E. [Hopital Cantonal Universitaire, Lausanne (Switzerland)

    1995-08-01

    The prognosis of stage III non-small cell lung cancer (NSCLC) can be improved by a combination of radiotherapy (RT) and chemotherapy (CT). In this study, the GOTHA group evaluated the feasibility, tolerance, tumour response, pattern of failure and effect on survival of a combination alternating accelerated hyperfractionated (AH) RT and CT in patients with tumour stage III NSCLC. Toxic effects were leucopenia, nausea and vomiting, mucositis, diarrhoea, alopecia and peripheral neuropathy. Alternating CT and AHRT, as used in this study, were well tolerated and allowed full dose delivery within less than 12 weeks. Initial response was not predictive of survival. The survival curve is encouraging and the 5 year survival is superior to the 5% generally observed with conventionally fractionated radiotherapy. (author).

  20. Hart Mountain - Work Yard Invasives Control and Implementation of Prevention Strategies

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Hart Mountain Refuge maintenance yard and borrow pits are currently heavily infested with numerous invasive weeds, the most problematic being Russian thistle...

  1. Facts about the Hart Mountain National Antelope Refuge Wilderness proposal [draft

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is a final draft of a leaflet meant to give more information about the Hart Mountain National Wildlife Refuge Wilderness proposal. Topics covered...

  2. Hart Mountain - Control of Cheatgrass in the Poker Jim Ridge Juniper Removal Area

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Since 2011 the Sheldon-Hart Mountain NWR Complex (Complex) has removed encroaching western juniper (Juniperus occidentalis) from within approximately 5,470 acres on...

  3. Een experimenteel onderzoek over de werking van de aconitine op het hart

    NARCIS (Netherlands)

    Boomsma, Jan Pieter

    1946-01-01

    Een literatuuroverzicht werd gegeven betreffende de geschiedenis, botanie, toxicologie, chemie en pharmacologie van aconitine. Vervolgens werden de verschijnselen, die gedurende de vergiftiging met aconitine aan het hart optraden, bestudeerd. Hiervoor werden de volgende experimenten verricht: 1. Mec

  4. Een experimenteel onderzoek naar de werking van het sulfanilamide op het hart

    NARCIS (Netherlands)

    Wiersma, Johan Hendrik

    1941-01-01

    Er werd een overzicht gegeven van de geschiedenis, chemie, bacteriologie, pharmacologie, toxicologie, bijwerkingen en therapie van het sulfanilamide. Vervolgens werden de verschijnselen, die tijdens de vergiftiging van het hart met sulfanilamide optraden, bestudeerd. Hiervoor werden de volgende expe

  5. Facts about the Hart Mountain National Antelope Refuge Wilderness proposal [final draft

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is a final draft of a leaflet meant to give more information about the Hart Mountain National Wildlife Refuge Wilderness proposal. Topics covered...

  6. EL PAPEL DE LA COACCIÓN EN LA TEORÍA DE LAS REGLAS DE HART The role of coercion in hart's theory of rules

    Directory of Open Access Journals (Sweden)

    Andrés Molina Ochoa

    2011-01-01

    Full Text Available El objetivo del artículo es ofrecer una nueva interpretación sobre el papel de la coacción en la teoría de las reglas de H. L. A. Hart. En primer lugar, se explica por qué una inadecuada interpretación de la coerción rinde imposible la distinción entre reglas primarias secundarias y primarias, central en el pensamiento de Hart. En segundo lugar, se distingue entre coerción y reproche social, además se analiza el carácter epistemológico de El Concepto de derecho. Con base en estas dos precisiones, se sugiere que el papel de la coacción en las reglas secundarias es determinar cuándo estamos en presencia de una regla. Finalmente, se proponen posibles líneas de investigación y de solución de controversias en torno a la teoría de Hart, según las tesis defendidas en el artículo.The objective of this article is to offer a new interpretation of the role of coercion in Hart's theory of rules. Firstly, it is discussed why an inaccurate interpretation of coercion makes impossible the important distinction between primary and secondary rules drawn by Hart. Secondly, it is analyzed the epistemological character of Hart's theory and the difference between coercion and social complains. Bases on these two clarifications, it is suggested that the role of coercion in secondary rules is to determine when we are in presence of a rule. Finally, some research lines and the solution to some controversies, following the main theses defended in this article, are suggested.

  7. Accelerated partial breast irradiation using intensity-modulated radiotherapy versus whole breast irradiation: 5-year survival analysis of a phase 3 randomised controlled trial.

    Science.gov (United States)

    Livi, Lorenzo; Meattini, Icro; Marrazzo, Livia; Simontacchi, Gabriele; Pallotta, Stefania; Saieva, Calogero; Paiar, Fabiola; Scotti, Vieri; De Luca Cardillo, Carla; Bastiani, Paolo; Orzalesi, Lorenzo; Casella, Donato; Sanchez, Luis; Nori, Jacopo; Fambrini, Massimiliano; Bianchi, Simonetta

    2015-03-01

    Accelerated partial breast irradiation (APBI) has been introduced as an alternative treatment method for selected patients with early stage breast cancer (BC). Intensity-modulated radiotherapy (IMRT) has the theoretical advantage of a further increase in dose conformity compared with three-dimensional techniques, with more normal tissue sparing. The aim of this randomised trial is to compare the local recurrence and survival of APBI using the IMRT technique after breast-conserving surgery to conventional whole-breast irradiation (WBI) in early stage BC. This study was performed at the University of Florence (Florence, Italy). Women aged more than 40years affected by early BC, with a maximum pathological tumour size of 25mm, were randomly assigned in a 1:1 ratio to receive either WBI or APBI using IMRT. Patients in the APBI arm received a total dose of 30 Gy to the tumour bed in five daily fractions. The WBI arm received 50Gy in 25 fractions, followed by a boost on the tumour bed of 10Gy in five fractions. The primary end-point was occurrence of ipsilateral breast tumour recurrences (IBTRs); the main analysis was by intention-to-treat. This trial is registered with ClinicalTrials.gov, number NCT02104895. A total of 520 patients were randomised (260 to external WBI and 260 to APBI with IMRT) between March 2005 and June 2013. At a median follow-up of 5.0 years (Interquartile Range (IQR) 3.4-7.0), the IBTR rate was 1.5% (three cases) in the APBI group (95% confidence interval (CI) 0.1-3.0) and in the WBI group (three cases; 95% CI 0.0-2.8). No significant difference emerged between the two groups (log rank test p=0.86). We identified seven deaths in the WBI group and only one in the APBI group (p=0.057). The 5-year overall survival was 96.6% for the WBI group and 99.4% for the APBI group. The APBI group presented significantly better results considering acute (p=0.0001), late (p=0.004), and cosmetic outcome (p=0.045). To our knowledge, this is the first randomised

  8. Performance characterization of siemens primus linear accelerator under small monitor unit and small segments for the implementation of step-and-shoot intensitymodulated radiotherapy

    Directory of Open Access Journals (Sweden)

    Reena P

    2006-01-01

    Full Text Available Implementation of step-and-shoot intensity-modulated radiotherapy (IMRT needs careful understanding of the accelerator start-up characteristic to ensure accurate and precise delivery of radiation dose to patient. The dosimetric characteristic of a Siemens Primus linear accelerator (LA which delivers 6 and 18 MV x-rays at the dose rate of 300 and 500 monitor unit (MU per minutes (min respectively was studied under the condition of small MU ranging from 1 to 100. Dose monitor linearity was studied at different dose calibration parameter (D1_C0 by measuring ionization at 10 cm depth in a solid water phantom using a 0.6 cc ionization chamber. Monitor unit stability was studied from different intensity modulated (IM groups comprising various combinations of MU per field and number of fields. Stability of beam flatness and symmetry was investigated under normal and IMRT mode for 20x20 cm2 field under small MU using a 2D Profiler kept isocentrically at 5 cm depth. Inter segment response was investigated form 1 to 10 MU by measuring the dose per MU from various IM groups, each consisting of four segments with inter-segment separation of 2 cm. In the range 1-4 MU, the dose linearity error was more than 5% (max -32% at 1 MU for 6 MV x-rays at factory calibrated D1_C0 value of 6000. The dose linearity error was reduced to -10.95% at 1 MU, within -3% for 2 and 3 MU and ±1% for MU ≥4 when the D1_C0 was subsequently tuned at 4500. For 18 MV x-rays, the dose linearity error at factory calibrated D1_C0 value of 4400 was within ±1% for MU ≥ 3 with maximum of -13.5 observed at 1 MU. For both the beam energies and MU/field ≥ 4, the stability of monitor unit tested for different IM groups was within ±1% of the dose from the normal treatment field. This variation increases to -2.6% for 6 MV and -2.7% for 18 MV x-rays for 2 MU/field. No significant variation was observed in the stability of beam profile measured from normal and IMRT mode. The beam flatness

  9. Quantitative analysis of results of quality control tests in linear accelerators used in radiotherapy; Analise quantitativa dos resultados de testes de controle de qualidade em aceleradores lineares usados em radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Passaro, Bruno M.; Rodrigues, Laura N. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Videira, Heber S., E-mail: bruno.passaro@gmail.com [Universidade de Sao Paulo (HCFMRP/USP), Sao Paulo, SP (Brazil). Faculdade de Medicina. Hospital das Clinicas

    2013-04-15

    The aim of this study is to assess and analyze the stability of the calibration factor of three linear accelerators, as well as the other dosimetric parameters normally included in a program of quality control in radiotherapy. The average calibration factors of the accelerators for the period of approximately four years for the Clinac 600C and Clinac 6EX were (0.998±0.012) and (0.996±0.014), respectively. For the Clinac 2100CD 6 MV and 15 MV was (1.008±0.009) and (1.006±0.010), respectively, in a period of approximately four years. The data of the calibration factors were divided into four subgroups for a more detailed analysis of behavior over the years. Through statistical analysis of calibration factors, we found that for the 600C and Clinacs 2100CD, is an expected probability that more than 90% of cases the values are within acceptable ranges according to TG-142, while for the Clinac 6EX is expected around 85% since this had several exchanges of accelerator components. The values of TPR20,10 of three accelerators are practically constant and within acceptable limits according to the TG-142. It can be concluded that a detailed study of data from the calibration factor of the accelerators and TPR{sub 20},{sub 10} from a quantitative point of view, is extremely useful in a quality assurance program. (author)

  10. Long-Term Outcome and Morbidity After Treatment With Accelerated Radiotherapy and Weekly Cisplatin for Locally Advanced Head-and-Neck Cancer: Results of a Multidisciplinary Late Morbidity Clinic

    Energy Technology Data Exchange (ETDEWEB)

    Ruetten, Heidi, E-mail: h.rutten@rther.umcn.nl [Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Pop, Lucas A.M.; Janssens, Geert O.R.J. [Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Takes, Robert P. [Department of Otorhinolaryngology and Head and Neck Surgery, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Knuijt, Simone [Department of Rehabilitation/Speech Pathology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Rooijakkers, Antoinette F. [Department of Oral and Maxillofacial Surgery, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Berg, Manon van den [Department of Gastroenterology-Dietetics, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Merkx, Matthias A. [Department of Oral and Maxillofacial Surgery, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Herpen, Carla M.L. van [Department of Medical Oncology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Kaanders, Johannes H.A.M. [Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands)

    2011-11-15

    Purpose: To evaluate the long-term outcome and morbidity after intensified treatment for locally advanced head-and-neck cancer. Methods and Materials: Between May 2003 and December 2007, 77 patients with Stage III to IV head-and-neck cancer were treated with curative intent. Treatment consisted of accelerated radiotherapy to a dose of 68 Gy and concurrent cisplatin. Long-term survivors were invited to a multidisciplinary outpatient clinic for a comprehensive assessment of late morbidity with special emphasis on dysphagia, including radiological evaluation of swallowing function in all patients. Results: Compliance with the treatment protocol was high, with 87% of the patients receiving at least five cycles of cisplatin and all but 1 patient completing the radiotherapy as planned. The 5-year actuarial disease-free survival and overall survival rates were 40% and 47%, respectively. Locoregional recurrence-free survival at 5 years was 61%. The 5-year actuarial rates of overall late Radiation Therapy Oncology Group (RTOG)/European Organization for Research and Treatment of Cancer (EORTC) Grade 3 and Grade 4 toxicity were 52% and 25% respectively. Radiologic evaluation after a median follow-up of 44 months demonstrated impaired swallowing in 57% of the patients, including 23% with silent aspiration. Subjective assessment using a systematic scoring system indicated normalcy of diet in only 15.6% of the patients. Conclusion: This regimen of accelerated radiotherapy with weekly cisplatin produced favorable tumor control rates and survival rates while compliance was high. However, comprehensive assessment by a multidisciplinary team of medical and paramedical specialists revealed significant long-term morbidity in the majority of the patients, with dysphagia being a major concern.

  11. The Controversy About The Essence Of Law: A Dispute Between Hart And Dworkin

    Directory of Open Access Journals (Sweden)

    Petrus C. K. Bello

    2012-01-01

    Full Text Available Does the law merely contain rules? Or does it also include morality? The debate between H.L.A. Hart and Ronald Dworkin revolved around this very issue. Hart considered the law is nothing more than a set of rules whereas Dworkin believed that the law contains not only the rules but also principles which are morality and justice. This paper is trying to explore the issue of the relationship of law and morality in the context of this debate between Hart and Dworkin. The debate itself is very significant in the study of law. Following their arguments we can learn a lot about how the law should be understood and practiced. By listening to their whole debate we will also know that Hart’s positivistic thought and Dworkin’s tendency towards the natural law are not mutually negating. Hart Positivism is not anti-morality. It is precisely through positivism which he defended Hart aims at safeguarding the law by morality; whereas Dworkin has shown what had previously forgotten by the legal positivistic way of thinking, that is moral principles are integral parts of the law.

  12. Factors associated with acute and late dysphagia in the DAHANCA 6 & 7 randomized trial with accelerated radiotherapy for head and neck cancer

    DEFF Research Database (Denmark)

    Mortensen, Hanna Rahbek; Overgaard, Jens; Jensen, Kenneth;

    2013-01-01

    Dysphagia is a common and debilitating side effect in head and neck radiotherapy (RT). Prognostic factors are numerous and their interrelationship not well understood. The aim of this study was to establish a multivariate prognostic model for acute and late dysphagia after RT, based on informatio...

  13. Validation of the total dysphagia risk score (TDRS) in head and neck cancer patients in a conventional and a partially accelerated radiotherapy scheme

    NARCIS (Netherlands)

    Nevens, Daan; Deschuymer, Sarah; Langendijk, Johannes A.; Daisne, Jean -Francois; Duprez, Frederic; De Neve, Wilfried; Nuyts, Sandra

    Background and purpose: A risk model, the total dysphagia risk score (TDRS), was developed to predict which patients are most at risk to develop grade >= 2 dysphagia at 6 months following radiotherapy (RT) for head and neck cancer. The purpose of this study was to validate this model at 6 months and

  14. Factors associated with acute and late dysphagia in the DAHANCA 6 & 7 randomized trial with accelerated radiotherapy for head and neck cancer

    DEFF Research Database (Denmark)

    Mortensen, Hanna R; Overgaard, Jens; Jensen, Kenneth

    2013-01-01

    Dysphagia is a common and debilitating side effect in head and neck radiotherapy (RT). Prognostic factors are numerous and their interrelationship not well understood. The aim of this study was to establish a multivariate prognostic model for acute and late dysphagia after RT, based on information...

  15. Aggressive simultaneous radiochemotherapy with cisplatin and paclitaxel in combination with accelerated hyperfractionated radiotherapy in locally advanced head and neck tumors. Results of a phase I-II trial

    Energy Technology Data Exchange (ETDEWEB)

    Kuhnt, T.; Pigorsch, S.; Pelz, T.; Haensgen, G.; Dunst, J. [Dept. of Radiotherapy, Martin Luther Univ., Halle (Germany); Becker, A. [Dept. of Radiotherapy, Martin Luther Univ., Halle (Germany); Dept. of Radiotherapy, Municipial Hospital, Dessau (Germany); Bloching, M.; Passmann, M. [Dept. of Head and Neck Surgery, Martin Luther Univ., Halle (Germany); Lotterer, E. [Dept. of Internal Medicine I, Martin Luther Univ., Halle (Germany)

    2003-10-01

    We have tested a very aggressive combination protocol with cisplatin and escalated paclitaxel in combination with accelerated hyperfractionated radiotherapy to assess the maximum tolerated dose (MTD), dose-limiting toxicity (DLT), overall toxicity, and response rate. Patients and Methods: The trial recruited 24 patients (21 males, three females, mean age 57 years) treated at our department from 1998 through 2001. Irradiation was administered in daily doses of 2 Gy up to 30 Gy followed by 1.4 Gy twice daily up to 70.6 Gy to the primary tumor and involved nodes and 51 Gy to the clinically negative regional nodes. The chemotherapy schedule included cisplatin in a fixed dose of 20 mg/m{sup 2} on days 1-5 and 29-33 and paclitaxel at increasing dose levels of 20, 25, 30 mg/m{sup 2} twice weekly over the whole treatment time. Patients were recruited in cohorts of three to six, and the MTD was reached if two out of six patients in one cohort developed DLT. DLT was defined as any grade 4 toxicity or any grade 3 toxicity requiring treatment interruption or unplanned hospitalization or any grade 3 neurotoxicity. We recruited mainly patients with large tumors for this protocol; all patients were stage IV, and the mean tumor volume (primary + metastases) amounted to 72 {+-} 61 cm{sup 3}. The mean follow-up was 30 months (range 4-39 months). Results: One early death (peritonitis and sepsis a t day 10) occurred, and 23 patients were evaluable for acute toxicity and response. The MTD of paclitaxel was reached at the third dose level (30 mg/m{sup 2} paclitaxel twice weekly). The DLT was severe mucositis grade 3 (n = 1) and skin erythema grade 4 (n = 2). After determining the MTD, another 14 patients were treated at the recommended dose level of paclitaxel with 25 mg/m{sup 2} twice weekly. In summary, 13/23 patients (57%) developed grade 3 and 10/23 (43%) grade 2 mucositis. Two patients (9%) had grade 4, five (22%) grade 3, and 16 (69%) grade 2 dermatitis. One patient died at day 30

  16. Review of A Life of H.L.A.Hart The Nightmare and the Noble Dream, by Nicola Lacey

    DEFF Research Database (Denmark)

    Jarvad, Ib Martin

    2006-01-01

    Review of Licola Lacey's biography of the legal philosopher H.L.A.Hart's life. The book io crammed with personal detail, but does not enlighten the reader as to why Hart in his legal philosophical orientation did not pay any particular attention to the common law, so characteristically English....

  17. 77 FR 21588 - Hart and Cooley, Inc., A Subsidiary of Tomkins, PLC Including On-Site Leased Workers from...

    Science.gov (United States)

    2012-04-10

    ... Employment and Training Administration Hart and Cooley, Inc., A Subsidiary of Tomkins, PLC Including On- Site... subsidiary of Tomkins, PLC, including on-site leased workers from Reliable, Masiello Employment Services... workers from Hart and Cooley, Inc., a subsidiary of Tomkins, PLC, including on-site leased workers...

  18. MACROMICROSCOPIC AND ULTRAMICROSCOPIC CHARACTERISTICS OF THE HART AND ITS BLOOD VESSELS IN MICE EHRLICHIOSIS INFECTION

    Directory of Open Access Journals (Sweden)

    Pokhil S. I.

    2013-12-01

    Full Text Available The macromicroscopic, ultramicroscopic studying change’s in the hart and its blood vessels in unlinear immunocomprometive laboratory male and female mice with the experimental ehrlichiosis is presented in this article. The cardiac destructive and degenerative changes,cardiomyopathy, cardiosclerosis had been established inexperimental animal group’s. The blood vessels endothelial lieyr disorganization, stasis, thrombosis has been noted.

  19. On the Road with Thomas Hart Benton: Images of a Changing America.

    Science.gov (United States)

    Johnson, Mark M.

    1999-01-01

    Summarizes the life and work of artist Thomas Hart Benton. Focuses on his paintings of the United States that capture the characteristics of regional life, customs, and nature before modern advancements and urbanization. Provides the itinerary for the 14- venue tour of 77 of Benton's works. (CMK)

  20. Klimaateffecten op de Natura 2000 moerascorridor, Quick Scan in het Groene Hart

    NARCIS (Netherlands)

    Verhoeven, S.; Paulissen, M.P.C.P.; Ouboter, M.; Wielen, van der S.; Wegman, R.M.A.; Masselink, L.; Goosen, H.

    2011-01-01

    Dit onderzoek is uitgevoerd om antwoord te vinden op de volgende vraag: Welke gevolgen heeft klimaatverandering op eutrofiëring, verdroging en verzilting in acht Natura 2000 gebieden in het Groene Hart? De hydrologische gegevens zijn ontleend aan de acht gebieden: Naardermeer, Botshol, Oostelijke Bi

  1. Depressie en hart- en vaatziekten: De rol van voeding, leefstijl en gezondheid

    NARCIS (Netherlands)

    Kamphuis, M.H.; Geerlings, M.I.; Tijhuis, M.A.R.; Kalmijn, S.; Grobbee, D.E.; Kromhout, D.

    2009-01-01

    Depressie is geassocieerd met een hoger risico op hart- en vaatziekten (HVZ). In dit onderzoek is prospectief onderzocht of depressieve symptomen verband houden met sterfte aan HVZ bij oudere mannen. Daarnaast is de rol onderzocht van leefstijl, voedingsfactoren en gezondheidstoestand in deze relati

  2. Cyberwar and B.H. Liddell Hart’s Indirect Approach

    Science.gov (United States)

    2016-06-10

    military history that allowed him to craft a persuasive theory that received support from those within the military and political establishment. However...ability to destroy physical infrastructure, while cyber espionage is concerned with information extraction. 53 sound calculation and coordination of...never lose sight of the psychological, and 92 Liddell Hart, Strategy, 5, 25, 217, 335. 58 only when

  3. Evaluation of a combined respiratory-gating system comprising the TrueBeam linear accelerator and a new real-time tumor-tracking radiotherapy system: a preliminary study.

    Science.gov (United States)

    Shiinoki, Takehiro; Kawamura, Shinji; Uehara, Takuya; Yuasa, Yuki; Fujimoto, Koya; Koike, Masahiro; Sera, Tatsuhiro; Emoto, Yuki; Hanazawa, Hideki; Shibuya, Keiko

    2016-07-08

    A combined system comprising the TrueBeam linear accelerator and a new real-time, tumor-tracking radiotherapy system, SyncTraX, was installed in our institution. The goals of this study were to assess the capability of SyncTraX in measuring the position of a fiducial marker using color fluoroscopic images, and to evaluate the dosimetric and geometric accuracy of respiratory-gated radiotherapy using this combined system for the simple geometry. For the fundamental evaluation of respiratory-gated radiotherapy using SyncTraX, the following were performed:1) determination of dosimetric and positional characteristics of sinusoidal patterns using a motor-driven base for several gating windows; 2) measurement of time delay using an oscilloscope; 3) positional verification of sinusoidal patterns and the pattern in the case of a lung cancer patient; 4) measurement of the half-value layer (HVL in mm AL), effective kVp, and air kerma, using a solid-state detector for each fluoroscopic condition, to determine the patient dose. The dose profile in a moving phantom with gated radiotherapy having a gating window ≤ 4 mm was in good agreement with that under static conditions for each photon beam. The total time delay between TrueBeam and SyncTraX was < 227 ms for each photon beam. The mean of the positional tracking error was < 0.4 mm for sinusoidal patterns and for the pattern in the case of a lung cancer patient. The air-kerma rates from one fluoroscopy direction were 1.93 ± 0.01, 2.86 ± 0.01, 3.92 ± 0.04, 5.28 ± 0.03, and 6.60 ± 0.05 mGy/min for 70, 80, 90, 100, and 110 kV X-ray beams at 80 mA, respectively. The combined system comprising TrueBeam and SyncTraX could track the motion of the fiducial marker and control radiation delivery with reasonable accuracy; therefore, this system provides significant dosimetric improvement. However, patient exposure dose from fluoroscopy was not clinically negligible.

  4. 实现SIS系统的HART仪表集中管理%Centralized management of HART instrument of SIS system

    Institute of Scientific and Technical Information of China (English)

    肖玉庆; 肖丽娟

    2013-01-01

      本文介绍了聚丙烯SIS系统的HART设备的管理,着重阐述了HART仪表的信号采集和HART通讯的设置,实现了利用上位机对HART仪表的集中管理。%  This paper introduces HART equipment management of the polypropylene SIS system,expounds the signal acquisition and communication settings of HART instrument,thus realizes centralized management of the HART instruments by computers.

  5. Accelerated high-dose radiotherapy alone or combined with either concomitant or sequential chemotherapy; treatments of choice in patients with Non-Small Cell Lung Cancer

    Directory of Open Access Journals (Sweden)

    Pieters Bradley R

    2007-07-01

    Full Text Available Abstract Background Results of high-dose chemo-radiotherapy (CRT, using the treatment schedules of EORTC study 08972/22973 or radiotherapy (RT alone were analyzed among all patients (pts with Non Small Cell Lung Cancer (NSCLC treated with curative intent in our department from 1995–2004. Material Included are 131 pts with medically inoperable or with irresectable NSCLC (TNM stage I:15 pts, IIB:15 pts, IIIA:57 pts, IIIB:43 pts, X:1 pt. Treatment Group I: Concomitant CRT: 66 Gy/2.75 Gy/24 fractions (fx/33 days combined with daily administration of cisplatin 6 mg/m2: 56 pts (standard. Group II: Sequential CRT: two courses of a 21-day schedule of chemotherapy (gemcitabin 1250 mg/m2 d1, cisplatin 75 mg/m2 d2 followed by 66 Gy/2.75 Gy/24 fx/33 days without daily cisplatin: 26 pts. Group III: RT: 66 Gy/2.75 Gy/24 fx/33 days or 60 Gy/3 Gy/20 fx/26 days: 49 pts. Results The 1, 2, and 5 year actuarial overall survival (OS were 46%, 24%, and 15%, respectively. At multivariate analysis the only factor with a significantly positive influence on OS was treatment with chemo-radiation (P = 0.024 (1-, 2-, and 5-yr OS 56%, 30% and 22% respectively. The incidence of local recurrence was 36%, the incidence of distant metastases 46%. Late complications grade 3 were seen in 21 pts and grade 4 in 4 patients. One patient had a lethal complication (oesophageal. For 32 patients insufficient data were available to assess late complications. Conclusion In this study we were able to reproduce the results of EORTC trial 08972/22973 in a non-selected patient population outside of the setting of a randomised trial. Radiotherapy (66 Gy/24 fx/33 days combined with either concomitant daily low dose cisplatin or with two neo-adjuvant courses of gemcitabin and cisplatin are effective treatments for patients with locally advanced Non-Small Cell Lung Cancer. The concomitant schedule is also suitable for elderly people with co-morbidity.

  6. Preliminary Experience in Treatment of Papillary and Macular Retinoblastoma: Evaluation of Local Control and Local Complications After Treatment With Linear Accelerator-Based Stereotactic Radiotherapy With Micromultileaf Collimator as Second-Line or Salvage Treatment After Chemotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Pica, Alessia, E-mail: Alessia.Pica@chuv.ch [Department of Radiation Oncology, Centre Hospitalier Universitaire Vaudois, Lausanne (Switzerland); Moeckli, Raphael [University Institute for Radiation Physics, Centre Hospitalier Universitaire Vaudois, Lausanne (Switzerland); Balmer, Aubin [Department of Radiation Oncology, Jules Gonin Eye Hospital, Lausanne (Switzerland); Beck-Popovic, Maja [Unit of Pediatric Oncology, University of Lausanne, Lausanne (Switzerland); Chollet-Rivier, Madeleine [Department of Anesthesiology, University of Lausanne, Lausanne (Switzerland); Do, Huu-Phuoc [University Institute for Radiation Physics, Centre Hospitalier Universitaire Vaudois, Lausanne (Switzerland); Weber, Damien C. [Department of Radiation Oncology, Geneva University Hospital, University of Geneva, Geneva (Switzerland); Munier, Francis L. [Department of Radiation Oncology, Jules Gonin Eye Hospital, Lausanne (Switzerland)

    2011-12-01

    Purpose: To determine the local control and complication rates for children with papillary and/or macular retinoblastoma progressing after chemotherapy and undergoing stereotactic radiotherapy (SRT) with a micromultileaf collimator. Methods and Materials: Between 2004 and 2008, 11 children (15 eyes) with macular and/or papillary retinoblastoma were treated with SRT. The mean age was 19 months (range, 2-111). Of the 15 eyes, 7, 6, and 2 were classified as International Classification of Intraocular Retinoblastoma Group B, C, and E, respectively. The delivered dose of SRT was 50.4 Gy in 28 fractions using a dedicated micromultileaf collimator linear accelerator. Results: The median follow-up was 20 months (range, 13-39). Local control was achieved in 13 eyes (87%). The actuarial 1- and 2-year local control rates were both 82%. SRT was well tolerated. Late adverse events were reported in 4 patients. Of the 4 patients, 2 had developed focal microangiopathy 20 months after SRT; 1 had developed a transient recurrence of retinal detachment; and 1 had developed bilateral cataracts. No optic neuropathy was observed. Conclusions: Linear accelerator-based SRT for papillary and/or macular retinoblastoma in children resulted in excellent tumor control rates with acceptable toxicity. Additional research regarding SRT and its intrinsic organ-at-risk sparing capability is justified in the framework of prospective trials.

  7. 肺癌超分割同步放化疗致急性放射性食管炎的研究%Research on Hyperfractionated Accelerated Radiotherapy-induced Acute Radiation Esophagitis in Lung Cancer

    Institute of Scientific and Technical Information of China (English)

    蓝柳; 杨春旭; 莫玉珍; 苏毅; 宁四海

    2011-01-01

    目的 观察超分割同步放化疗治疗局部晚期非小细胞肺癌(NSCLC)患者放射性食管炎的发生情况,评价其安全性,探讨超分割放疗导致放射性食管炎损伤的有效预测指标.方法 初治NSCLC 48例,采用超分割同步放化疗24例,放疗剂量:56.0~64.4 Gy/40~46次,1.4 Gy/次,2次/d;常规分割同步放化疗24例,放疗剂量:60.0~66 Gy/30~33次,2.0 Gy/次,1次/d.两组均接受依托泊苷+顺铂(EP)方案同步化疗.采用RTOG标准评价急性放射性食管炎发生情况,分析急性放射性食管炎的相关临床及物理因素.结果 48例患者均完成治疗计划.超分割组≥2级和≥3急性放射性食管炎发生率高于对照组(P<0.05).急性放射性食管炎最早在第10天发生,累计剂量为22.4 Gy,在疗程的第17天后其发生率明显上升.超分割组中食管LETT30、LETT35、V35与≥2级急性放射性食管炎显著相关(P<0.01).结论 超分割同步放化疗治疗NSCLC急性放射性食管炎的发生率及严重程度较常规分割同步放化疗明显增加,并且发生时间早;食管LETT30、LETT35、V35和周累计剂量是预测超分割同步放化疗致急性放射性食管炎的可靠指标.%Objective To observed the incidence of acute radiation esophagitis and analyze the factors as predictors of acute radiotherapy-induced acute radiation esophagitis for locally advanced non-small cell lung cancer( LA-NSCLC )patients treated with 3DCRT were reviewed. To analyze the efficacy and safety of hyperfractionated accelerated radiotherapy for the treatment of lung cancer and assess effective indexes in those patient. Methods Forty eight patients with LA-NSCLC were allocated to treatment group( 24 cases ), treated with hyperfractionated accelerated radiotherapy.Radiotherapy was delivered at 1. 4 Gy/fraction ,56. 0 - 64. 4 Gy/40 - 45 fractions , twice a day. The control group( 24 cases )treated with conventional fractionation , with delivered at 2 Gy fraction , 60. 0

  8. Radiotherapy; Strahlentherapie

    Energy Technology Data Exchange (ETDEWEB)

    Wannenmacher, M. [Heidelberg Univ., Mannheim (Germany). Abt. fuer Klinische Radiologie; Debus, J. [Univ. Heidelberg (Germany). Abt. Radioonkologie und Strahlentherapie; Wenz, F. (eds.) [Universitaetsklinikum Mannheim (Germany). Klinik fuer Strahlentherapie und Radioonkologie

    2006-07-01

    The book is focussed on the actual knowledge on the clinical radiotherapy and radio-oncology. Besides fundamental and general contributions specific organ systems are treated in detail. The book contains the following contributions: Basic principles, radiobiological fundamentals, physical background, radiation pathology, basics and technique of brachytherapy, methodology and technique of the stereotactic radiosurgery, whole-body irradiation, operative radiotherapy, hadron therapy, hpyerthermia, combined radio-chemo-therapy, biometric clinical studies, intensity modulated radiotherapy, side effects, oncological diagnostics; central nervous system and sense organs, head-neck carcinomas, breast cancer, thorax organs, esophagus carcinoma, stomach carcinoma, pancreas carcinoma, heptabiliary cancer and liver metastases, rectal carcinomas, kidney and urinary tract, prostate carcinoma, testicular carcinoma, female pelvis, lymphatic system carcinomas, soft tissue carcinoma, skin cancer, bone metastases, pediatric tumors, nonmalignant diseases, emergency in radio-oncology, supporting therapy, palliative therapy.

  9. Technical and functional considerations of the portable electron accelerator, mobetron, for intraoperative radiotherapy; Consideraciones tecnicas y funcionales del acelerador de electrones portatil, mobetron, para radioterapia intraoperatoria

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Cases, F. J.; Javier de Luis, F.; Herranz Gonzalez, M.; Canon Rodriguez, R.; Munoz Miguelanez, T.; Aakki, L.; Azinovic Gamo, I.; Brugarolas Masllorens, A.

    2013-07-01

    This work reveals the peculiarities which must be taken into account for the clinical use of this type of accelerators, regarding its operational stability and describe the problems that arise in the logistics work, both from the point of view of the physical dosimetry and radiation protection. (Author)

  10. A progress report on the work toward propagation and reintroduction of the threatened plant American Hart's Tongue Fern (Phyllitis scolopendrium)

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Report describes efforts to propogate the fern spores in the lab. Attempts to propagate the spores from the Am. Hart's Tongue Fern in the Lab is reviewed. Spores...

  11. Vulnerability assessment and strategies for the Sheldon National Wildlife Refuge and Hart Mountain National Antelope Refuge Complex : Final report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report provides the results of the Refuge Vulnerability Assessment (RVA) for the Sheldon National Wildlife Refuge and Hart Mountain National Antelope Refuge...

  12. Analysis and Mapping of Vegetation and Habitat for the Hart Mountain National Antelope Refuge

    Energy Technology Data Exchange (ETDEWEB)

    Tagestad, Jerry D.

    2010-06-01

    The Lakeview, Oregon, office of the U.S. Fish and Wildlife Service (USFWS) contracted Pacific Northwest National Laboratory to classify vegetation communities on Hart Mountain National Antelope Refuge in northeastern Nevada. The objective of the mapping project was to provide USFWS refuge biologists and planners with detailed vegetation and habitat information that can be referenced to make better decisions regarding wildlife resources, fuels and fire risk, and land management. This letter report describes the datasets and methods used to develop vegetation cover type and shrub canopy cover maps for the Hart Mountain National Antelope Refuge. The two map products described in this report are 1) a vegetation cover classification that provides updated information on the vegetation associations occurring on the refuge and 2) a map of shrub canopy cover based on high-resolution images and field data.

  13. Application study of wind power technology to the city of Hart, Michigan, 1977

    Energy Technology Data Exchange (ETDEWEB)

    Asmussen, J.; Krauss, O.; Park, G. L; Linvill, D. E

    1978-01-01

    To determine the feasibility of wind-electric systems, six generation expansion alternatives were examined for Hart, Michigan--a city of 2,500 located near Lake Michigan where the average coastal wind velocities range from 5 to 7 m/s. Five of the alternatives included combinations of 500 and 1500 kW wind turbines (1975 GE parameters) and a 1 MW hydro plant while the last was a 3600 kW diesel generator. Wind velocity was estimated using data from U.S. Coast Guard stations along the shore and verified by a two-year measurement program. The Hart electrical system was represented by an hourly production cost program and the total cost calculations followed the ERDA/EPRI standard for solar energy evaluation.

  14. Empirical as Criterion of law Effectiveness: between Alf Ros and Hebert Hart

    Directory of Open Access Journals (Sweden)

    Horácio Wanderlei Rodrigues

    2016-04-01

    Full Text Available Legal positivism positions the law in the formal validity. However, the law theory also focuses on other aspects of empirical to understand the legal phenomenon, we seek such elements in the works of Herbert Hart and Alf Ross. To Hart the rule of recognition’s content, that we can use to meet the validity of the right, should be measured empirically in each legal system and may also (but not necessarily incorporate moral elements. Differently, the realistic Ross theory is independent of the validity criterion and he argues that the effectiveness is verifiable by the effective application of the law by legal authorities.

  15. Neo-Fascisme, norme, literatuur: Oor Pieter Stoffberg se Die hart van ’n bond

    Directory of Open Access Journals (Sweden)

    M. de Jong

    1992-05-01

    Full Text Available In this article it is argued that Pieter Stoffberg's collection of stories, Die hart van ’n hond, forces the reader to constitute racist frames in order to interpret. Furthermore the author proposes that Kristeva's formalisation of the 'negation of negation', developed in The Revolution of Poetic Language, can theorise the textual process in these stories as a transgression in which the taboo on political rightist conservatism in a "New South Africa' is broken. To produce this transgression, the text places the reader in the position of the other, a position in which normative decision-taking is precluded. This itself could, however, constitute an ethical moment. On the basis of the Neo-Fascist aspects of Die hart van ’n hond, the article proposes a re-introduction of the ethical in literary’ discourse and critically comments on Afrikaans literary culture in this respect.

  16. Um modelo de positivismo jurídico: o pensamento de Herbert Hart

    OpenAIRE

    Stolz, Sheila

    2007-01-01

    Um dos grandes méritos de Hart foi tentar compreender e explicar o direito enquanto sistema normativo que exibe algumas características proeminentes, entre elas: a relação que estabelece com a linguagem, a coação, o poder e a moral. Ainda que defensor do positivismo jurídico, Hart não nega que os sistemas jurídicos contemporâneos são complexos e que positivaram princípios e valores morais que têm transcendência no que é o direito válido, uma vez que acrescentam dimensõ...

  17. Oliver Hart and His Property Right Theory%哈特和产权理论

    Institute of Scientific and Technical Information of China (English)

    陈永伟

    2009-01-01

    @@ 奥列佛·哈特(Oliver Hart)原籍英国,出身名门望族,其祖上是有名的银行家,父亲是著名的结核病研究专家.但哈特似乎对银行业不感兴趣,也无意子承父业,而是对数学表现出了更大的兴趣.

  18. Entre o direito e a moralidade: o debate Hart-Devlin

    Directory of Open Access Journals (Sweden)

    Lucas Ferreira Cabreira

    2016-05-01

    Full Text Available O presente artigo abordará o tema da relação entre moral e direito a partir do histórico debate entre Herbert Hart e Patrick Devlin. Inicialmente, serão expostos os argumentos de Devlin, que entende que todos os ramos do direito protegem moralidade, e que a finalidade do direito penal especificamente é a imposição de princípios morais. Entende ainda que não é qualquer moral que o direito protege, mas a moralidade convencional, representada pela moralidade do “homem no júri”. Na sequência, serão expostas duas críticas de Hart às posições de Devlin, que centram na identificação da falta de critérios racionais para a identificação da moralidade e a inaptidão de Devlin em demonstrar o direito como protetor da moral, que para Hart se encontra na proteção aos valores universais que previnem as condutas que causam danos a outrem. Na sequência, serão apresentadas as réplicas dos dois autores aos argumentos expostos. Por fim, será apresentado uma contribuição pessoal para o debate a partir de Green (2010 e Dworkin (1966.

  19. Determination of radiation levels by neutrons in an accelerator for radiotherapy; Determinacion de niveles de radiacion por neutrones en un acelerador para radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Paredes G, L.; Salazar B, M.A. [Instituto Nacional de Investigaciones Nucleares, Apdo. Postal 18-1027, 11801 Mexico D.F. (Mexico); Genis S, R. [Fundacion Clinica Medica Sur, Puente de Piedra 150, Col. Torriello Guerra, Tlalpan 14050, Mexico D.F. (Mexico)

    1998-12-31

    It was determined the radiation levels by neutrons due to photonuclear reactions ({gamma}, n) which occur in the target, levelling filter, collimators and the small pillow blinding of a medical accelerator Varian Clinac 2100C of 18 MeV, using thermoluminescent dosemeters UD-802AS and US-809AS. The experimental values were presented for the patient level, inside and outside of the radiation field, as well as for the small pillow. (Author)

  20. Locally advanced head and neck cancer treated with accelerated radiotherapy, the hypoxic modifier nimorazole and weekly cisplatin. Results from the DAHANCA 18 phase II study

    DEFF Research Database (Denmark)

    Bentzen, Jens; Toustrup, Kasper; Eriksen, Jesper Grau

    2015-01-01

    with stage III or IV HNSCC of the larynx, oropharynx, hypopharynx, or oral cavity where included between January 2007 and December 2010. The prescribed radiotherapy (RT) dose was 66-68 Gy in 2 Gy fractions, 6 F/W. The hypoxic radiosensitiser nimorazole was given orally at a dose of 1200 mg/m(2) before each......, and 149 patients (66%) received the full dose of nimorazole. The five-year actuarial LRC, EFS and OS rates were 80%, 67% and 72%, respectively. The LRC rates according to site were: oropharynx: 88%, larynx: 77%, hypopharynx 72% and oral cavity 49%, respectively. HPV/p16 staining was obtained in 141...... of the 150 oropharyngeal cancers. Of these, 112 (79%) were p16 pos and 29 (21%) were p16 neg. LRC for the p16 neg oropharyngeal cancers was poorer than for the p16 pos (74% vs. 91%; p = 0.02). Tube feeding during treatment was necessary for 146 (64%) patients. At 12 months this number was reduced to 6...

  1. Biological and medical research with accelerated heavy ions at the Bevalac, 1974--1977. [Planning for use for radiotherapy and as radiation source for diagnostic radiography

    Energy Technology Data Exchange (ETDEWEB)

    Elam, S. (ed.)

    1977-04-01

    The Bevalac, a versatile high-energy heavy-ion accelerator complex, has been in operation for less than two years. A major purpose for which the Bevalac was constructed was to explore the possibility of heavy-ion teams for therapy for certain forms of cancer. Significant progress has been made in this direction. The National Cancer Institute has recognized the advantages that these and other accelerated particles offer, and heavy ions have been included in a long-term plan for particle therapy that will assess by means of controlled therapeutic tests the value of various modalities. Since accelerated heavy ions became available, the possibility of other contributions, not planned, became apparent. We are developig a new diagnostic method known as heavy-ion radiography that has greatly increased sensitivity for soft-tissue detail and that may become a powerful tool for localizing early tumors and metastases. We have discovered that radioactive beams are formed from fragmentation of stable deflected beams. Use of these autoradioactive beams is just beginning; however, we know that these beams will be helpful in localizing the region in the body where therapy is being delivered. In addition, it has been demonstrated that instant implantation of the radioactive beam allows direct measurements of blood perfusion rates in inaccessible parts of the body, and such a technique may become a new tool for the study of fast hot atom reactions in biochemistry, tracer biology and nuclear medicine. The Bevalac will also be useful for the continuation of previously developed methods for the control of acromegaly, Cushing's disease and, on a research basis, advanced diabetes mellitus with vascular disease. The ability to make small bloodless lesions in the brain and elsewhere with heavy-ion beams has great potential for nervous-system studies and perhaps later for radioneurosurgery.

  2. Commissioning and quality assurance of the X-ray volume Imaging system of an image-guided radiotherapy capable linear accelerator

    Science.gov (United States)

    Muralidhar, K. R.; Murthy, P. Narayana; Kumar, Rajneesh

    2008-01-01

    An Image-Guided Radiotherapy–capable linear accelerator (Elekta Synergy) was installed at our hospital, which is equipped with a kV x-ray volume imaging (XVI) system and electronic portal imaging device (iViewGT). The objective of this presentation is to describe the results of commissioning measurements carried out on the XVI facility to verify the manufacturer's specifications and also to evolve a QA schedule which can be used to test its performance routinely. The QA program consists of a series of tests (safety features, geometric accuracy, and image quality). These tests were found to be useful to assess the performance of the XVI system and also proved that XVI system is very suitable for image-guided high-precision radiation therapy. PMID:19893694

  3. SIMPLY ANALYZE THE APPLICATION OF HART COMMUNICATOR IN INSTRUMENT%浅析HART通讯器在仪表中的应用

    Institute of Scientific and Technical Information of China (English)

    李蕾; 赵旭; 刘海岭

    2011-01-01

    This paper introduces HART protocol and function of the model 275 HART Communicator, and enumerates several application of HART communicator in actual instrument. It has active effects to feature application and popularization of the HART Communicator.%介绍了HART通讯协议及275型HART通讯器的功能,并列举了HART通讯器在冶金行业现场仪表中的几种具体应用,对HART通讯器的进一步使用和推广起到了积极的作用。

  4. HardwareSoftware Co-design for Heterogeneous Multi-core Platforms The hArtes Toolchain

    CERN Document Server

    2012-01-01

    This book describes the results and outcome of the FP6 project, known as hArtes, which focuses on the development of an integrated tool chain targeting a heterogeneous multi core platform comprising of a general purpose processor (ARM or powerPC), a DSP (the diopsis) and an FPGA. The tool chain takes existing source code and proposes transformations and mappings such that legacy code can easily be ported to a modern, multi-core platform. Benefits of the hArtes approach, described in this book, include: Uses a familiar programming paradigm: hArtes proposes a familiar programming paradigm which is compatible with the widely used programming practice, irrespective of the target platform. Enables users to view multiple cores as a single processor: the hArtes approach abstracts away the heterogeneity as well as the multi-core aspect of the underlying hardware so the developer can view the platform as consisting of a single, general purpose processor. Facilitates easy porting of existing applications: hArtes provid...

  5. Adapter Design Based on Wireless HART Protocol%基于无线HART协议的适配器设计

    Institute of Scientific and Technical Information of China (English)

    薛定国; 牛斗

    2011-01-01

    基于无线HART协议的适配器,以MSP430F系列单片机为核心,结合CC2520数据收发模块和信号分离/合成模块,实现了上位机对HART仪表中数字信息的管理.适配器通过微处理器控制数据收/发模块与上位机通信,解析上位机指令,控制信号分离/合成模块实现对HART仪表数字信息的读取和写入.基于无线HART协议的适配器在HART仪表的维护和监控过程中有较高的应用价值.%The adapter based on wireless HART uses the microcontroller MSP430F MCUs as the core, combined with CC2520 data transceiver modules and signal separation/synthesis modules,realizing the management of digital information from the host computer to the HART instrument. The adapter communicates with the host computer by controlling the data transceiver modules through the microcontroller and analyzes its commands. It implements read and write of the digital information from the HART instruments by controlling the signal separation/synthesis modules. The adapter based on wireless HART has a high application value in HART instrument maintenance and monitoring.

  6. Integrating a MRI scanner with a 6 MV radiotherapy accelerator: dose increase at tissue-air interfaces in a lateral magnetic field due to returning electrons

    Energy Technology Data Exchange (ETDEWEB)

    Raaijmakers, A J E; Raaymakers, B W; Lagendijk, J J W [Department of Radiotherapy, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, Utrecht (Netherlands)

    2005-04-07

    In the framework of the development of the integration of a MRI-scanner with a linear accelerator, the influence of a lateral, magnetic field on the dose distribution has to be determined. Dose increase is expected at tissue-air boundaries, due to the electron return effect (ERE): electrons entering air will describe a circular path and return into the phantom causing extra dose deposition. Using IMRT with many beam directions, this exit dose will not constitute a problem. Dose levels behind air cavities will decrease because of the absence of electrons crossing the cavity. The ERE has been demonstrated both by simulation and experiment. Monte Carlo simulations are performed with GEANT4, irradiating a water-air-water phantom in a lateral magnetic field. Also an air tube in water has been simulated, resulting in slightly twisted regions of dose increase and decrease. Experimental demonstration is achieved by film measurement in a perspex-air-perspex phantom in an electromagnet. Although the ERE causes dose increase before air cavities, relatively flat dose profiles can be obtained for the investigated cases using opposite beam configurations. More research will be necessary whether this holds for more realistic geometries with the use of IMRT and whether the ERE can be turned to our advantage when treating small tumour sites at air cavities.

  7. LEGAL REALISM AND HART: A DISCUSSION OF THE INDETERMINANCY OF THE LAW

    OpenAIRE

    CLÁUDIA CHAVES MARTINS JORGE

    2010-01-01

    O presente trabalho tem por objetivo apresentar uma discussão sobre a indeterminação do Direito. Para tanto, serão analisados os preceitos do realismo jurídico e os pensamentos de Herbert L. A. Hart. O pensamento de Holmes e a sociologia jurídica de Pound abriram caminho para o realismo jurídico norteamericano e serviram de fundamento para autores considerados realistas, como Jerome Frank e Llewellyn, entre outros. Um dos fortes argumentos do realismo jurídico se encontra no...

  8. Grossman-Hart (1986) Goes Global: Incomplete Contracts, Property Rights, and the International Organization of Production

    OpenAIRE

    Antras, Pol

    2011-01-01

    I survey the influence of Grossman and Hart's (1986) “The Costs and Benefits of Ownership: A Theory of Vertical and Lateral Integration,†94 Journal of Political Economy 691–719.) seminal paper in the field of International Trade. I discuss the implementation of the theory in open-economy environments and its implications for the international organization of production and the structure of international trade flows. I also review empirical work suggestive of the empirical relevance of t...

  9. Postmastectomy radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Shikama, Naoto; Koguchi, Masahiko; Sasaki, Shigeru; Kaneko, Tomoki; Shinoda, Atsunori; Nishikawa, Atsushi [Shinshu Univ., Matsumoto, Nagano (Japan). School of Medicine

    2000-10-01

    Since there have been few reports on postmastectomy radiotherapy having a high evidence level in Japan, the significance of postoperative radiotherapy and the irradiation techniques were reviewed based on reports from Western countries. Authors focused on the indications for postoperative irradiation, irradiation methods (irradiation sites, irradiation techniques; prosthetics, methods of irradiating the chest wall and lymph nodes, timing of irradiation), and complications, and discuss them. The factors thought to be adaptable to postmastectomy radiotherapy have been listed. Axillary lymph node metastasis and the size of the primary focus are thought to be important factors in locoregional recurrence. The chest wall and the supraclavicular lymph nodes are the usual sites of irradiation after mastectomy. The irradiation method consists of tangential irradiation of the chest wall and single-field irradiation of the supraclavicular lymph nodes, with 46-50 Gy in fractional doses of 1.8-2 Gy x 5/w is administered for 4.5-5.5 weeks. The timing of irradiation in the West is generally after chemotherapy. Adverse radiation effects include ischemic heart disease, pneumonitis, arm edema, rib fractures, and brachial plexus paralysis. The frequency of these complications is increased by the combined use of chemotherapy or surgery. The breast cancer cure rate in Japan is generally better than in the West. It remains to be determined whether the clinical data from Europe and America are applicable to the treatment of breast cancer in Japan. To address this issue, a clinical investigation should be performed in Japan with close cooperation between surgeons, physicians, pathologists, and radiotherapists. (K.H.)

  10. Dosimetry for electron Intra-Operative RadioTherapy: Comparison of output factors obtained through alanine/EPR pellets, ionization chamber and Monte Carlo-GEANT4 simulations for IORT mobile dedicate accelerator

    Science.gov (United States)

    Marrale, Maurizio; Longo, Anna; Russo, Giorgio; Casarino, Carlo; Candiano, Giuliana; Gallo, Salvatore; Carlino, Antonio; Brai, Maria

    2015-09-01

    In this work a comparison between the response of alanine and Markus ionization chamber was carried out for measurements of the output factors (OF) of electron beams produced by a linear accelerator used for Intra-Operative Radiation Therapy (IORT). Output factors (OF) for conventional high-energy electron beams are normally measured using ionization chamber according to international dosimetry protocols. However, the electron beams used in IORT have characteristics of dose per pulse, energy spectrum and angular distribution quite different from beams usually used in external radiotherapy, so the direct application of international dosimetry protocols may introduce additional uncertainties in dosimetric determinations. The high dose per pulse could lead to an inaccuracy in dose measurements with ionization chamber, due to overestimation of ks recombination factor. Furthermore, the electron fields obtained with IORT-dedicated applicators have a wider energy spectrum and a wider angular distribution than the conventional fields, due to the presence of electrons scattered by the applicator's wall. For this reason, a dosimetry system should be characterized by a minimum dependence from the beam energy and from angle of incidence of electrons. This become particularly critical for small and bevelled applicators. All of these reasons lead to investigate the use of detectors different from the ionization chamber for measuring the OFs. Furthermore, the complete characterization of the radiation field could be accomplished also by the use of Monte Carlo simulations which allows to obtain detailed information on dose distributions. In this work we compare the output factors obtained by means of alanine dosimeters and Markus ionization chamber. The comparison is completed by the Monte Carlo calculations of OFs determined through the use of the Geant4 application "iort _ therapy" . The results are characterized by a good agreement of response of alanine pellets and Markus

  11. Simplified geometric model for the calculation of neutron yield in an accelerator of 18 MV for radiotherapy; Modelo geometrico simplificado para el calculo del rendimiento de neutrones en un acelerador de 18 MV para radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Paredes G, L.C.; Balcazar G, M. [ININ, 52750 La Marquesa, Estado de Mexico (Mexico); Francois L, J.L. [FI-UNAM, 04510 Mexico D.F. (Mexico); Azorin N, J. [UAM-I, 09340 Mexico D.F. (Mexico)

    2008-07-01

    The results of the neutrons yield in different components of the bolster of an accelerator Varian Clinac 2100C of 18 MV for radiotherapy are presented, which contribute to the radiation of flight of neutrons in the patient and bolster planes. For the calculation of the neutrons yield, a simplified geometric model of spherical cell for the armor-plating of the bolster with Pb and W was used. Its were considered different materials for the Bremsstrahlung production and of neutrons produced through the photonuclear reactions and of electro disintegration, in function of the initial energy of the electron. The theoretical result of the total yield of neutrons is of 1.17x10{sup -3} n/e, considering to the choke in position of closed, in the patient plane with a distance source-surface of 100 cm; of which 15.73% corresponds to the target, 58.72% to the primary collimator, 4.53% to the levelled filter of Fe, 4.87% to the levelled filter of Ta and 16.15% to the closed choke. For an initial energy of the electrons of 18 MeV, a half energy of the neutrons of 2 MeV was obtained. The calculated values for radiation of experimental neutrons flight are inferior to the maxima limit specified in the NCRP-102 and IEC-60601-201.Ed.2.0 reports. The absorbed dose of neutrons determined through the measurements with TLD dosemeters in the isocenter to 100 cm of the target when the choke is closed one, is approximately 3 times greater that the calculated for armor-plating of W and 1.9 times greater than an armor-plating of Pb. (Author)

  12. Cor pulmonale. De rol van het emphyseem en zijn complicaties bij het tekortschieten van het rechter hart

    NARCIS (Netherlands)

    1955-01-01

    Het vraagstuk van de rol, die het emphyseem en zijn complicaties spelen bij de overbelasting van het rechter hart, bracht ons er toe eerst onze aandacht te wijden aan het emphyseem zelf. Wij hebben onder meer stilgestaan bij de bemoeilijkte respiratie (waarbij het aandeel, dat elastische en visceuze

  13. Discussion of Wireless HART System Engineering Design%Wireless HART无线系统工程设计探讨

    Institute of Scientific and Technical Information of China (English)

    方原柏

    2011-01-01

    有线HART仪表是目前应用最普遍的仪表,总数已达到3 000万台以上,由HART通信基金会提出的IEC 62591标准是工业过程测量和控制领域的首个无线国际标准。介绍了采用该标准的Wireless HART技术的系统构成,探讨了Wireless HART系统工程设计的应用场合、设计要点、安装要点和图纸设计。%Wired HART is the most common instrument in use nowadays,the total number has reached to more than 30 million.IEC 62591 standards proposed by the HART Communication Foundation is the first wireless international standard of industrial process measurement and control area.The system constitution of Wireless HART technology with this standard is described firstly,and the application field,key design point,main installation element and engineering design of Wireless HART systems are discussed accordingly.

  14. Da harpa ao altar : as pontes da espiritualidade em The Bridge, de Hart Crane

    OpenAIRE

    Júdice, Maria Benedita de Almeida Garrett Mendes Pinto

    2007-01-01

    A presente dissertação tem por tema o tratamento da espiritualidade em The Bridge, de Hart Crane. Ao longo do trabalho, a ponte de Brooklyn, a musa inspiradora do poema, é analisada como estrutura arquitectónica, o seu processo de construção e as condições políticas e económico-sociais da América que permitiram esse mesmo processo são descritos e a simbologia da ponte enquanto artefacto arquitectónico e poético é explorada. É o seu papel simbólico que me permite, pois, analisar as secções do ...

  15. HART技术的特点及进展%The character and development of HART techniqne

    Institute of Scientific and Technical Information of China (English)

    王鸿昌; 李宝康

    2002-01-01

    综述了HART通信技术及其在工业自动化仪表领域的应用,介绍了HART通信基金会(HCF)发布的技术规范文件及开发信息,并对以HART 6为代表的HART技术的最新进展作了介绍,说明HART技术仍在发展,它已从智能仪表领域走出,向系统级连接交换发展,甚至通过特定的接口设备探讨通过公众交换网(PSTN)及无线技术实现更加广阔的应用.

  16. Variabilidad genética de Hartón del Valle mediante RAM

    Directory of Open Access Journals (Sweden)

    Ana M Piedrahíta

    2008-01-01

    Full Text Available El Hartón del Valle (HV hace parte de las siete razas criollas de ganado bovino colombiano y de acuerdo con los criterios de la FAO está considerado como vulnerable. Para estudiar su variabilidad genética fueron muestreados 33 individuos HV y tres animales de la raza Holstein, como control externo. Se extrajo ADN utilizando el método de Salting Out y las muestras fueron analizadas mediante la técnica molecular RAM (Randon amplified microsatellites. Se utilizaron los cebadores CGA, CCA, TG, y CT. El valor promedio de heterocigosidad esperada fue de 0.26 y el F ST fue 0.39 ± 0.03. Con el índice de Dice-Nei Li y agrupando con el método UPGMA se distinguieron dos grupos: uno integrado por dos hatos de conservación y el otro por cuatro fincas que han compartido reproductores.

  17. Geologic map of the Hart Peak Quadrangle, California and Nevada: a digital database

    Science.gov (United States)

    Nielson, Jane E.; Turner, Ryan D.; Bedford, David R.

    1999-01-01

    The Hart Peak 1:24,000-scale quadrangle is located about 12 km southwest of Searchlight, Nevada, comprehending the eastern part of the Castle Peaks, California, and most of the Castle Mountains and the northwestern part of the Piute Range, in California and Nevada. The Castle Peaks area constitutes the northeasternmost part of the northeast-trending New York Mountains. The Castle Mountains straddle the California-Nevada State line between the Castle Peaks and north-trending Piute Range. The southern part of the Piute Range, near Civil War-era Fort Piute, adjoins Homer Mountain mapped by Spencer and Turner (1985). Adjacent and nearby 1:24,000-scale quadrangles include Castle Peaks, East of Grotto Hills, Homer Mountain, and Signal Hill, Calif.; also Tenmile Well and West of Juniper Mine, Calif. and Nev. The oldest rocks in the Hart Peak quadrangle are Early Proterozoic gneiss and foliated granite that crop out in the northern part of the quadrangle on the eastern flank of the Castle Peaks and in the central Castle Mountains (Wooden and Miller, 1990). Paleozoic rocks are uncommon and Mesozoic granitic rocks are not found in the map area. The older rocks are overlain nonconformably by several km of Miocene volcanic deposits, which accumulated in local basins. Local dikes and domes are sources of most Miocene eruptive units; younger Miocene intrusions cut all the older rocks. Upper Miocene to Quaternary gravel deposits interfinger with the uppermost volcanic flows; the contact between volcanic rocks and the gravel deposits is unconformable locally. Canyons and intermontane valleys contain dissected Quaternary alluvialfan deposits that are mantled by active drainage and alluvial fan detritus.

  18. Radiotherapy for breast cancer and pacemaker; Radiotherapie pour un cancer du sein et stimulateur cardiaque

    Energy Technology Data Exchange (ETDEWEB)

    Menard, J.; Campana, F.; Bollet, M.A.; Dendale, R.; Fournier-Bidoz, N.; Marchand, V.; Mazal, A.; Fourquet, A.; Kirova, Y.M. [Oncologie-radiotherapie, institut Curie, 26, rue d' Ulm, 75005 Paris (France); Kirov, K.M.; Esteve, M. [Departement d' anesthesie-reanimation-douleur, institut Curie, 75005 Paris (France)

    2011-06-15

    Purpose. - Patients with permanent cardiac pacemakers occasionally require radiotherapy. Therapeutic Irradiation may cause pacemakers to malfunction due to the effects of ionizing radiation or electromagnetic interference. We studied the breast cancer patients who needed breast and/or chest wall and lymph node irradiation to assess the feasibility and tolerance in this population of patients. Patients and methods. - From November 2008 to December 2009, more than 900 patients received radiotherapy for their breast cancer in our department using megavoltage linear accelerator (X 4-6 MV and electrons). Among them, seven patients were with permanent pacemaker. All patients have been treated to the breast and chest wall and/or lymph nodes. Total dose to breast and/or chest wall was 50 Gy/25 fractions and 46 Gy/23 fractions to lymph nodes. Patients who underwent conserving surgery followed by breast irradiation were boosted when indicated to tumour bed with 16 Gy/8 fractions. All patients were monitored everyday in presence of radiation oncologist to follow the function of their pacemaker. All pacemakers were controlled before and after radiotherapy by the patients' cardiologist. Results. - Seven patients were referred in our department for postoperative breast cancer radiotherapy. Among them, only one patient was declined for radiotherapy and underwent mastectomy without radiotherapy. In four cases the pacemaker was repositioned before the beginning of radiotherapy. Six patients, aged between 48 and 84 years underwent irradiation for their breast cancer. Four patients were treated with conserving surgery followed by breast radiotherapy and two with mastectomy followed by chest wall and internal mammary chain, supra- and infra-clavicular lymph node irradiation. The dose to the pacemaker generator was kept below 2 Gy. There was no pacemaker dysfunction observed during the radiotherapy. Conclusion. - The multidisciplinary work with position change of the pacemaker

  19. Stereotactic multiple are radiotherapy. IV--Haemangioblastoma.

    Science.gov (United States)

    Chakraborti, P R; Chakrabarti, K B; Doughty, D; Plowman, P N

    1997-04-01

    Our initial experience in the treatment of haemangioblastoma using conventional external beam radiotherapy and stereotactic radiotherapy (radiosurgery), by the linear accelerator method, is reported. Six haemangioblastomas in five patients were treated with a mean follow-up of 40 months (range 14-60). Five haemangioblastomas in four patients were treated with stereotactic radiotherapy, where four showed complete radiological response and the fifth was static. Neurological symptoms and signs improved in those patients. The sixth haemangioblastoma was situated close to the pituitary and optic chiasm, and was treated with conventionally fractionated external beam radiotherapy. The lesion showed partial response. No complications were noted in this patient group. This series complements and extends the relatively sparse published literature demonstrating that radiotherapy is an effective option for treating haemangioblastomas. Radiosurgery often lends itself particularly well to these discrete lesions allowing highly focused treatment. For patients with multiple and metachronous cerebellar haemangioblastomas as part of the von Hipple-Lindau syndrome, the data support a policy of conventionally fractionated external beam radiotherapy to the whole cerebellum of 50-55 Gy followed, after a period of time, by radiosurgery to persisting lesions (patients 3 and 4).

  20. Radiotherapy for Hodgkin lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Specht, Lena [Rigshospitalet Copenhagen Univ. (Denmark). Depts. of Oncology and Haematology; Yahalom, Joachim (eds.) [Memorial Sloan-Kettering Cancer, New York, NY (United States). Dept. of Radiation Oncology

    2011-07-01

    This book deals in detail with all aspects of the best practice in modern radiotherapy for Hodgkin lymphoma. It provides the background and rationale for the inclusion of radiotherapy in today's combined-modality approach, including special clinical situations such as Hodgkin lymphoma in children, in the pregnant patient, and in the elderly. Radiotherapy planning using state-of-the-art imaging, target definition, planning software, and treatment equipment is expounded in detail. Acute and long-term side effects of radiotherapy are analyzed, and the implications for modern radiotherapy approaches in Hodgkin lymphomas are explained. (orig.)

  1. 91st Congress : 1st Session : S. 3014 [Hart Mountain NAR, Alaska Maritime NWR, Three Arch Rocks NWR, Oregon Islands NWR, Bitter Lake NWR, Malheur NWR

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is a bill meant to designate certain lands in the Hart Mountain National Antelope Refuge, Alaska Maritime National Wildlife Refuge, Three Arch Rocks...

  2. HART手操器在可燃气体探测器检验方面的应用%Application of HART Communicator in Combustible Gas Detector Test

    Institute of Scientific and Technical Information of China (English)

    高佩旺; 刘志刚

    2012-01-01

    The composition of HART communication protocol, combustible gas detector works and HART communicator in the combustible gas detector calibration application were introdued. Convenient and practical was the character of HART communicator calibration combustible gas detector, and it wouldl be widely used with the development of HART.%简要介绍了HART通信协议的构成、可燃气体探测器的工作原理及HART手操器在可燃气体探测器校验中的应用。认为HART手操器校验可燃气体探测器方便、实用,随着HART可燃气体探测器的发展具有很好的应用前景。

  3. Applied Research of HART Communication Protocol of Field Bus%现场总线HART通信协议应用综述

    Institute of Scientific and Technical Information of China (English)

    李明富; 曾友洲; 冻孝波; 蔡昌勇

    2012-01-01

    This paper researches into the open digital field bus and the HART protocol in field bus through literature study, stuns up the characteristics of HART protocol through the study of the protocol and the latest technology, suggests the application of HART protocol according to the HART communication protocol, then provides the foundation for further study.%本文通过文献法研究了开放式、数字化的现场总线及现场总线中的HART协议,通过对该协议和最新技术的研究,总结出了现场总线的HART协议的特点,根据HART通信协议的特点给出了HART协议的应用,为下一步研究提供了基础。

  4. A Low Overhead Routing Strategy for WirelessHART%一种低开销无线HART路由策略

    Institute of Scientific and Technical Information of China (English)

    黄聪; 董利达; 管林波

    2013-01-01

    无线HART协议是一种新兴的适用于工业领域的高可靠性无线传感器协议规范.基于无线HART网络特点,提出一种低开销的路由策略,其基本思想是将全网Graph拓扑结构转化为双树拓扑结构,上行路由采用无线HART协议中提出的Graph路由方式,而下行路由采用多路径方式.此策略简化了Graph路由方式,降低网络管理器的Graph拓扑以及节点的路由存储开销,同时降低全网络的路由维护开销.测试表明,此策略在保证网络通信可靠性的基本条件下有效的降低了路由开销.%WirelessHART communication protocol is an emerging wireless sensor network communication protocol specification, which is applied to the industrial field because of its high reliability. According to the characteristics of wirelessHART data stream,a double-tree structure is used for original network topology. On the basis of it,the paper proposes a routing strategy for the wirelessHART network. The basic idea of the strategy is that the full-redundance routing method proposed in the WirelessHART specification is reserved for upstream routing, while the multi-path routing method is used for downstream routing. The strategy simplifies Graph routing, thus reducing the storage overhead of the network manager and device nodes, as well as routing maintenance overhead of whole network. Experimental results show that our algorithm is effective to reduce the routing overhead, while still keeping basic reliability of communication.

  5. Design of HART Configuration Software Based on Windows%基于Windows的HART组态软件设计

    Institute of Scientific and Technical Information of China (English)

    张夏; 魏文雄; 余淼; 郭江伟

    2012-01-01

    针对PC在Windows操作系统下实时性差和状态机功能不易实现的问题,根据PC自带的性能计数器,构造一个高精度、低开销的定时器,其计数精度可以达到毫秒级以下.采用AES算法对HART控制命令进行加密保护,实验结果证明,HART组态软件具有较好的实时性和安全性,适用于工业控制的现场数据通信.%Under the circumstances of the Windows operating system of personal computer, the function of state machine is not easy to realize. Based on PC's own performance counters, this paper presents a method to make a high-precision and low-overhead timer, which satisfies the strict demands for real time of HART control software. Meanwhile, AES algorithm is applied to protect the HART control commands. Experimental result shows that the HART configuration software has a high degree of real-time and safety, which provides a solution to the data communication in industrial control field.

  6. HART-II Acoustic Predictions using a Coupled CFD/CSD Method

    Science.gov (United States)

    Boyd, D. Douglas, Jr.

    2009-01-01

    This paper documents results to date from the Rotorcraft Acoustic Characterization and Mitigation activity under the NASA Subsonic Rotary Wing Project. The primary goal of this activity is to develop a NASA rotorcraft impulsive noise prediction capability which uses first principles fluid dynamics and structural dynamics. During this effort, elastic blade motion and co-processing capabilities have been included in a recent version of the computational fluid dynamics code (CFD). The CFD code is loosely coupled to computational structural dynamics (CSD) code using new interface codes. The CFD/CSD coupled solution is then used to compute impulsive noise on a plane under the rotor using the Ffowcs Williams-Hawkings solver. This code system is then applied to a range of cases from the Higher Harmonic Aeroacoustic Rotor Test II (HART-II) experiment. For all cases presented, the full experimental configuration (i.e., rotor and wind tunnel sting mount) are used in the coupled CFD/CSD solutions. Results show good correlation between measured and predicted loading and loading time derivative at the only measured radial station. A contributing factor for a typically seen loading mean-value offset between measured data and predictions data is examined. Impulsive noise predictions on the measured microphone plane under the rotor compare favorably with measured mid-frequency noise for all cases. Flow visualization of the BL and MN cases shows that vortex structures generated in the prediction method are consist with measurements. Future application of the prediction method is discussed.

  7. Analysis of Temperature and Rainfall Trends in Vaal-Harts Irrigation Scheme, South Africa

    Directory of Open Access Journals (Sweden)

    Josiah Adeyemo

    2016-07-01

    Full Text Available Agriculture is crucially dependent on the timely availability of adequate amount of water and a conducive climate. Temperature and rainfall patterns impact the availability of water for agricultural uses. Therefore, temperature and rainfall are twin important environmental factors in agricultural activities such as tillage, planting, irrigation and mechanization. The characteristics of the Vaal-Harts temperature data for year 1996 to 2010 and rainfall data for year 1983 to 2010 were examined in this study using statistical techniques. Basic statistical properties of the data were determined using the mean, variance, coefficient of variation and Pearson’s correlation coefficient. Temperature and rainfall observations with the average of about 17.44 were used. The minimum and maximum temperatures recorded were 9.720C and 23.520C. The Coefficient of variation (CV was found to be about 29.59. Variance is a measure of how far a set of numbers is spread out; and the variance of this set of observations is 26.625. The average yearly temperature increases insignificantly by a constant of about 0.117 (p = 0.163; 95% CI: -0.054 – 0.288, while rainfall shows decreasing trend annually which means that the dry season will be drier. The involvement of non-zero values in the serial correlation indicated the significance of the deterministic component in the data. The results of this analysis enhance our understanding of the characteristics of air temperature and rainfall in the study area for effective planning of farming operations.

  8. Hart and Beijing School of Combined Learning%赫德与北京同文馆

    Institute of Scientific and Technical Information of China (English)

    贾熟村

    2012-01-01

    Robert Hart worked as inspector-General of Chinese Maritime Customs Service for decades. Just like establishing modern navy, postal service, banking systems and railways in China, he tried to build Beijing School of Combined Learning. The funds for this school were provided by the Customs, and most of the teachers were engaged by him. The school provided programs like foreign languages, mathematics, physics, geography, law, political economy and medicine, and built a printing factory, a physics lab, an observatory and a library. All these won him the title of "father of the School of Combined Learning" . This school cultivated numerous talents and made tremendous contributions to China' s culture, teaching, science, technology, and diplomacy.%赫德担任中国海关总税务司达数十年之久,他把北京同文馆与建设中国近代海军、邮政、银行、铁路事项列为他在中国的事业,努力经营,力求成功。同文馆的经费由海关筹措,外国教习也大多由他礼聘,设置了外文、数学、物理、化学、地理、法学、政治经济学、医学等多种专业,还有近代印刷厂、物理实验室、天文台、图书馆等,被称为“同文馆”之父,培养了大量人才,为中国文教、科技、外交的近代化作出了卓越贡献。

  9. HART Field Communication Protocol%HART现场通信协议

    Institute of Scientific and Technical Information of China (English)

    孙广军

    2002-01-01

    HART(可寻址远程传感器数据公路)协议作为一种高效的通信技术,能充分挖掘数字设备的潜力.在保留传统的4~20*!mA模拟信号的同时,HART协议开拓了系统与现场智能仪表进行双向数字通信的能力.HART协议不仅给现场智能仪表的通信提供了最佳方案,而且为其它各种现场通信协议提供了最广泛的支持.HART协议在仪表设备中的采用程度超过其它任何数字通信技术.几乎可以为任一工业过程应用找到符合HART协议的产品支持.在与现已投用的仪表设备向后兼容方面,HART协议是唯一的通信方案.这种向后兼容性确保现已敷设的电缆和目前控制策略在未来仍能发挥有效作用.简要介绍了HART通信协议的一般运行模式和基本的协议模型.

  10. Radiotherapy of esthesioneuroblastoma. Radiotherapie beim Aesthesioneuroblastom

    Energy Technology Data Exchange (ETDEWEB)

    Strnad, V. (Erlangen-Nuernberg Univ., Erlangen (Germany). Strahlentherapeutische Klinik und Poliklinik); Grabenbauer, G.G. (Erlangen-Nuernberg Univ., Erlangen (Germany). Strahlentherapeutische Klinik und Poliklinik); Dunst, J. (Erlangen-Nuernberg Univ., Erlangen (Germany). Strahlentherapeutische Klinik und Poliklinik); Sauer, R. (Erlangen-Nuernberg Univ., Erlangen (Germany). Strahlentherapeutische Klinik und Poliklinik)

    1994-02-01

    From 1985 through 1990, twelve patients with estehesioneuroblastoma have been treated at the Department of Radiotherapy at the University of Erlangen. Two had Kadish stage A, one stage B, and nine stage C. There were seven males and five females with a mean age of 43 years. Eleven patients had combined trancranial-transbasal surgery prior to radiotherapy (five R0-, four R1-, and two patients R2-resections) and one received radiotherapy only. The dose was 12 to 60 Gy (mean 54 Gy) in 1.8 Gy to 2 Gy per fraction. 8/12 patients (67%) were locally controlled. One had progressive disease during radiotherapy after partial resection and died. Three had local recurrences, one in-field and two marginal. One patient with a local recurrence developed cervical lymph node metastases, and one locally controlled patient developed bone metastases but is alive eight years after chemotherapy plus radiotherapy for metastatic disease. The five-year-overall and recurrence-free survival was 72% and 55%, respectively. (orig./MG)

  11. Harting:Intend to Lead China Linker Market%德资雅迪HARTING:意欲称雄中国风能连接器市场

    Institute of Scientific and Technical Information of China (English)

    王淑梅

    2008-01-01

    @@ 2008年10月29-31日,2008北京国际风能大会暨展览会在中国国际展览中心(新馆)隆重召开,Vestas、Suzlon、Gamesa、金风科技、华锐等业界知名企业悉数到场,德资雅迪HARTING公司(以下简称"雅迪HARTING")也在其中,并向观众展示了他们用于风能领域的创新产品及完善的解决方案.

  12. Targeted tumor radiotherapy

    Directory of Open Access Journals (Sweden)

    Unak Perihan

    2002-01-01

    Full Text Available Targeted tumor radiotherapy is selectively delivery of curative doses of radiation to malignant sites. The aim of the targeted tumor radiotherapy is to use the radionuclides which have high LET particle emissions conjugated to appropriate carrier molecules. The radionuclides are selectively collected by tumor cells, depositing lethal doses to tumor cells while no admission occur to normal cells. In theory, targeted radiotherapy has several advantages over conventional radiotherapy since it allows a high radiation dose to be administered without causing normal tissue toxicity, although there are some limitations in the availability of appropriate targeting agents and in the calculations of administered doses. Therefore, for routine clinical applications more progress is still needed. In this article, the potential use of targeted tumor radiotherapy is briefly reviewed. More general aspects and considerations, such as potential radionuclides, mechanisms of tumor targeting was also outlined.

  13. Current status and potential perspectives in classical radiotherapy technology

    Directory of Open Access Journals (Sweden)

    Dabić-Stanković Kata M.

    2004-01-01

    Full Text Available Introduction and potentials of classical radiotherapy After purchase of radiotherapy equipment in 2003, classic radiation therapy in Serbia will reach the highest world level. In order to define the highest standards in radiation technology, we analyzed the current status and potential perspectives of radiation therapy. Technological levels of radiotherapy in developed countries An analysis of present situation in the USA, assumed as the most developed in the world, was done. Available data, collected in the last 3 years (equipment assortment, therapy modalities, workload and manpower for 284 radiotherapy centers, out of potential 2050, were analyzed. Results were presented as crude percentage and mached to point current status. Results of analysis and discussion The analysis showed that CLINAC accelerators are the most popular (82.7%, as well as, ADAC (43.7% and Focus (CMS (27.4% systems for therapy planning. Movement towards virtual simulation is evident (59.3%, although classic ”simulation” is not fully eliminated from the radiotherapy chain. The most popular brachytherapy afterloader is Microselectron HDR (71%. About 64.4% centers use IMPAC communication/verification/record system that seems more open than Varis. All centers practice modern radiotherapy modalities and techniques (CFRT, IMRT, SRS/SRT, TBI, IORT, IVBHRT, HDR BHRT, etc.. CT and MRI availability is out of question, but PET is available in 3% of centers, however this percentage is rapidly growing. Up to 350 new patients per year are treated by one accelerator (about 35 pts. a day. Centers are relatively small and utilize 2-3 accelerators on average. Average FTE staffing norm is 4 radiation oncologists, 2-3 medical radiotherapy physicists, about 3 certified medical dosimetrists and about 6 radiotherapy technologists. Technological aspects and conclusion In the past 5 years relative stagnation in classic radiotherapy has been observed. In spite of substantial investments in

  14. A New Cancer Radiotherapy System Using Multi Robotic Manipulators

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seung Ho; Lee, Nam Ho; Lee, Byung Chul; Jeung, Kyung Min; Lee, Seong Uk; Bae, Yeong Geol; Na, Hyun Seok [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-10-15

    The CyberKnife system is state-of-the-art cancer treatment equipment that combines an image tracking technique, artificial intelligence software, robot technology, accelerator technology, and treatment simulation technology. The current CyberKnife System has significant shortcomings. The biggest problem is that it takes a longer time to treat a tumor. A long treatment time gives stress to patients. Furthermore it makes the patients uncomfortable with radiation and thus it is difficult to measure the exact radiation dose rate to the tumor in the processing. Linear accelerators for radiation treatment are dependent on imports, and demand high maintenance cost. This also makes the treatment cost higher and prevents the popularization of radiation. To solve the disadvantages of the existing CyberKnife, a radiation treatment robot system applied to several articulated robots is suggested. Essential element techniques for new radiotherapy robot system are investigated and some problems of similar existing systems are analyzed. This paper presents a general configuration of a new radiation robot treatment system including with a quantitative goal of the requirement techniques. This paper described a new radiotherapy robot system to track the tumor using multiple articulated robots in real time. The existing CyberKnife system using a single robot arm has disadvantages of a long radiotherapy time, high medical fee, and inaccurate measurement of the radiotherapy dose. So a new radiotherapy robot system for tumors has been proposed to solve the above problems of conventional CyberKnife systems. Necessary technologies to configure new the radiotherapy robot system have been identified. Quantitative targets of each technology have been established. Multiple robot arms are adopted to decrease the radiotherapy time. The results of this research are provided as a requisite technology for a domestic radiotherapy system and are expected to be the foundation of new technology. The

  15. Review on heavy ion radiotherapy facilities and related ion sources (invited)

    NARCIS (Netherlands)

    Kitagawa, A.; Fujita, T.; Muramatsu, M.; Biri, S.; Drentje, A. G.

    Heavy ion radiotherapy awakens worldwide interest recently. The clinical results obtained by the Heavy Ion Medical Accelerator in Chiba at the National Institute of Radiological Sciences in Japan have clearly demonstrated the advantages of carbon ion radiotherapy. Presently, there are four

  16. 赫德与英德续借款%Hart and Loan Renewal from Britain and Germany

    Institute of Scientific and Technical Information of China (English)

    张志勇

    2014-01-01

    The Qing Government paid Japan reparations with three large sums of loans: loans from Russia and France, loans and loan renewal from Britain and Germany. After his contribution to getting loans from Britain and Germany, Hart gave counsel to HSBC Bank, proposing to Yano Ryukei, Japanese ambassador to China, that China pay back remaining reparations in 10-year installment, in order to prevent loans from falling into hands of Russia and France, but his proposal was rejected. Finally, Zongli Yanmen had to entrust loan financing to Hart. Hart managed to get loan renewal from Britain and Germany and assisted the Qing Government to pay off reparations to Japan with loan renewal from Britain and Germany.%中国对日赔款的赔付主要是通过三次大借款来完成的,它们分别为俄法借款、英德借款及续借款。赫德帮助英德借款取得成功后,为了防止剩余对华借款落入俄法手中,赫德继续为汇丰银行出谋划策,并向日本驻华公使矢野文雄提出了分10年还清剩余赔款的方案,但未取得成功。最终在向各方借款无着、日本拒绝赔款展期的情况下,总理衙门不得不仍将借款事宜交给赫德办理,赫德从而帮助英德续借款取得成功,同时也帮助清政府利用英德续借款偿清了对日赔款。

  17. The Application of Wireless EARTTM%无线HART(WirelessHARTTM)的应用The Application of Wireless HARTTM

    Institute of Scientific and Technical Information of China (English)

    HCF中国

    2009-01-01

    对HART协议做了简单的技术回顾,介绍HCF开发无线HART的目标及任务.通过对无线HART(WirelessHARTTM)的无线网络设计及其组成设备功能的描述,得以更加细致地领会HCF对无线HART应用的期望,即新技术的应用应贴近实际应用场合.

  18. [Recent developments in radiotherapy of hepatocellular carcinoma].

    Science.gov (United States)

    Seong, Jinsil

    2004-12-01

    With the accumulation of clinical experiences, the efficacy of radiotherapy has been recognized in management scheme for HCC. While hepatologists are beginning to show less reluctance for applying radiotherapy to the treatment of HCC, it is necessary that the hepatologists be informed of the rapid developments in technical strategy for radiation oncology. Recent advances in several technologies have opened a new era in radiation oncology. Modern imaging technologies can provide a 3-dimensional model of patient's anatomy, and this allows radiation oncologists to identify accurate tumor volumes as well as the tumors' relationship with the adjacent normal tissues. Moreover, the development of the computer-controlled multileaf collimator systems now enables physicians to perform precise beam shaping and to modulate the radiation dose distribution. A combination of these systems, 3-DCRT, is rapidly replacing the more conventional 2-D radiotherapy. 3-DCRT has evolved into a more sophisticated technology, intensity modulated radiotherapy (IMRT). In IMRT, with the powerful computer-aided optimization process, the radiation dose can be delivered to the target using highly complex isodose profiles. This new technology has been further developed into IGRT, which combines the CT-images scanning system and radiation equipments into one hardware package, and this system is currently ready for clinical application. In parallel with the radiation technologies described above, the strategy of stereotactic radiation has evolved from the conventional linear accelerator-based system to a gammaknife, and more recently, to a cyberknife. These systems are primarily based on the concept of radiosurgery. Currently, various radiation technologies have been adopted for the radiotherapy of HCC. In this article, each strategy will be discussed as well as the indications for radiotherapy and the radiation-related complications.

  19. Dose rate measurement due to activation of the head of a linear accelerator used in radiotherapy; Medida de tasa de dosis debido a la activacion del cabezal de un acelerador lineal utilizado en radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Ruiz-Zorrilla, J.; Minambres Moro, A.; Fernandez Leton, P.; Martinez Gomez, L. C.; Gillaranz Moreno, R.; Castro Novais, J.; Zucca Aparicio, D.; Perez Moreno, J. M.

    2011-07-01

    Electron accelerators which produce photon energies greater than 8 MV dose rates can present after irradiation due to the emission of neutrons and consequent formation of products of activation, the aim of this study is to measure the variation in the rate of dose over time produced by an accelerator of 25 MV and try to locate any of the isotopes produced and conservatively estimate the dose received by workers.

  20. [The security system of SIEMENS digital linear accelerator].

    Science.gov (United States)

    Wang, Jianping

    2013-03-01

    The security system plays an important role to protect the safety of patients and equipment in radiotherapy. The principle and structure of three kinds of security system of the Siemens digital linear accelerator were analyzed with some examples.

  1. Medical applications of accelerators

    CERN Document Server

    Rossi, Sandro

    1998-01-01

    At Present, about five thousands accelerators are devoted to biomedical applications. They are mainly used in radiotherapy, research and medical radioisotopes production. In this framework oncological hadron-therapy deserves particular attention since it represents a field in rapid evolution thanks to the joint efforts of laboratories with long experiences in particle physics. It is the case of CERN where the design of an optimised synchrotron for medical applications has been pursued. These lectures present these activities with particular attention to the new developments which are scientifically interesting and/or economically promising.

  2. 基于HART协议的过程控制系统接口卡%The HART-Based Interface Module for Process Control System

    Institute of Scientific and Technical Information of China (English)

    吴安定; 林铭锻

    2001-01-01

    主要论述了过程自动控制系统中HART协议接口卡的开发技术,对系统结构、HART接口卡的功能、电路设计、软件部分等作了具体介绍。试验表明,该设计是可行的。%The developing technology of HART-based interface module in process control system is mainly described. The structure of system, the functions of HART interface module, the design of circuit and the software are introduced concretely. The tests show that the design is feasible.

  3. Design of HART Protocol Flowmeter Based on MSP430%基于MSP430的HART协议流量计设计

    Institute of Scientific and Technical Information of China (English)

    翟会

    2014-01-01

    叙述了基于MSP430单片机的HART协议流量计设计,介绍了该流量计的结构及其软硬件设计。详细介绍了采用HT20C15及AD421构成的HART协议通信线路设计。%This paper describes the design of flowmeter which use HART protocol based on MSP430 microcontroller. Describes the structure of its hardware and software. Describes the details of HART protocol communication circuit design based on HT20C15 and AD421.

  4. HART智能变送器及其转换系统设计%The Design of HART Smart Transmitter and Convert System

    Institute of Scientific and Technical Information of China (English)

    王春麟; 周鑫

    2011-01-01

    This article introduce the hardware design of the smart transmitter based on the HART protocol.It could also communicate with the upper computer,has the simple circuit structure and low power consumption ability.%介绍基于HART协议的智能变送器的硬件设计。在保证低功耗的前提下实现HART协议的物理层,并通过HART/RS232转换器与上位机通信,具有电路简单,低功耗的特点。

  5. Experimental radiotherapy and clinical radiobiology. Vol. 20. Proceedings; Experimentelle Strahlentherapie und Klinische Strahlenbiologie. Bd. 20. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Baumann, Michael; Dahm-Daphi, Jochen; Dikomey, Ekkehard; Petersen, Cordula; Rodemannn, Hans-Peter; Zips, Daniel (eds.)

    2011-07-01

    The proceedings include contributions on the following issues: laser driven proton accelerators on the way for radiotherapy, radiobiological evaluation of new radiations; molecular factors of radiation response; biological targeting; EGFR epidermal growth factor receptor/targeting - combined internal and external irradiation, radiobiology of normal tissues; dose-volume histograms for the radiotherapy: curves without radiobiological relevance or important information for the therapy planning; HPV (human papilloma virus) and radiation sensitivity of HNSCC (head and neck squamous cell carcinomas): evidence, radiobiological mechanism, clinical consequences and perspectives; mechanisms of action and intertumoral heterogeneity of response to EGFR inhibition in radiotherapy of solid tumors; evaluation of biomarkers for radiotherapy.

  6. Planning a Radiotherapy Department.

    Science.gov (United States)

    van der Merwe, D

    2017-02-01

    The master planning of new radiotherapy facilities requires the input and engagement of a range of highly specialised professionals, both in the construction and health sector. Although radiation protection and safety aspects of radiotherapy services are universal, low and middle income countries are often presented with unique challenges that also need to be considered, e.g. competing needs within the health sector, lack of financial and human resources, environmental factors like poor provision of transport or electrical power, inadequate regulatory infrastructure, etc. Efforts to establish, upgrade or expand radiotherapy services should therefore not only focus on the technology that is appropriate and sustainable, but also be mindful of the need for quality, safety and optimal utilisation of technology. The workflow in a radiotherapy department can be facilitated by strategic placement of the main functional areas into the concept design. Copyright © 2016 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  7. Nanoparticle-guided radiotherapy

    DEFF Research Database (Denmark)

    2012-01-01

    The present invention relates to a method and nano-sized particles for image guided radiotherapy (IGRT) of a target tissue. More specifically, the invention relates to nano-sized particles comprising X-ray-imaging contrast agents in solid form with the ability to block x-rays, allowing for simult...... for simultaneous or integrated external beam radiotherapy and imaging, e.g., using computed tomography (CT)....

  8. Saliva in relation to dental erosion before and after radiotherapy

    DEFF Research Database (Denmark)

    Jensdottir, Thorbjorg; von Buchwald, Christian; Nauntofte, Birgitte

    2013-01-01

    Abstract Objective. Low saliva flow and abnormal saliva composition are common conditions after radiotherapy for oral cavity and pharyngeal cancer. Both conditions increase the susceptibility to dental caries and erosion, which may be further accelerated by changes in food preferences. The aim of...

  9. Communication Circuit Design of Intelligent Instrument Based on HART Protocol%基于HART协议的智能仪表通信电路设计

    Institute of Scientific and Technical Information of China (English)

    李春丽; 李巍

    2013-01-01

    From the functions and protocols of HART intelligent instrument,difficult and key technologies of the HART intelligent instrument communication design are discussed,and the practical circuit of the complete HART protocol intelligent instrument communication is designed.It can achieve the basic function of the HART protocol intelligent instrument communication.The intelligent instrument can be used for real-time monitoring and low power,and is compatible with analog and digital communication.%从HART协议智能仪表的功能和协议要求出发,详细分析了HART协议智能仪表通信的设计重点、难点和关键技术,设计了完整的HART协议智能仪表通信的实用电路,可以实现HART协议智能仪表通信的基本功能.该智能仪表可用于实时监测,低功耗并且具有兼容模拟和数字通信的能力.

  10. Intraoperative radiotherapy in the theatre room with electron beams: technical and dosimetric description of Sordina LIAC accelerator; Radioterapia intraoperatoria en quirofano con haces de electrones: descripcion tecnica y dosimetrica del acelerador dedicado Sordina LIAC

    Energy Technology Data Exchange (ETDEWEB)

    Sendon del Rio, J. R.; Ayala Lazaro, R.; Gomez Cores, S.; Garcia Hernandez, M. J.; Polo Cezon, R.; Jimenez Rojas, R.; Lopez Bote, M. A.

    2015-05-01

    n this work we show our experience during the commissioning of a mobile electron-beam accelerator dedicated to intraoperative radiation therapy in the theatre room. The linac is a Sordina LIAC 12 MeV model with a hard-docking applicator system. We describe the linac, the measurement methods and the specific dosimetry. The dosimetric behavior is also discussed. Differences with other applicator systems can be explained from the particular head design of the linac. (Author)

  11. Radiotherapy for the medulloblastoma

    Energy Technology Data Exchange (ETDEWEB)

    Gose, Kyuhei; Imajo, Yoshinari; Imanaka, Kazufumi (Kobe Univ. (Japan). School of Medicine)

    1983-08-01

    Eighteen patients with medulloblastoma, treated between 1972 and 1981, at Kobe University School of Medicine, were retrospectively studied. Of those completing post operative irradiation, 50% have survived for 2 years, 15% for 5 years and mean survival periods was 22.2 months. 13 out of 18 patients developed local recurrence and spinal dissemination. The mean time from the initial radiotherapy to recurrence was 8.5 months. It was suggested that posterior fossa should recieve 5,000 rad, the spine should 2,000 rad and recurrences should be treated by the combination of radiotherapy and chemotherapy.

  12. 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.     

  13. Determination of the exposure speed of radiation emitted by the linear accelerator, using the code MCNP5 to evaluate the radiotherapy room shields of ABC Hospital; Determinacion de la rapidez de exposicion de la radiacion emitida por el acelerador lineal, utilizando el codigo MCNP5, para evaluar los blindajes de la sala de radioterapia del Hospital ABC

    Energy Technology Data Exchange (ETDEWEB)

    Corral B, J. R.

    2015-07-01

    Humans should avoid exposure to radiation, because the consequences are harmful to health. Although there are different emission sources of radiation, generated by medical devices they are usually of great interest, since people who attend hospitals are exposed in one way or another to ionizing radiation. Therefore, is important to conduct studies on radioactive levels that are generated in hospitals, as a result of the use of medical equipment. To determine levels of exposure speed of a radioactive facility there are different methods, including the radiation detector and computational method. This thesis uses the computational method. With the program MCNP5 was determined the speed of the radiation exposure in the radiotherapy room of Cancer Center of ABC Hospital in Mexico City. In the application of computational method, first the thicknesses of the shields were calculated, using variables as: 1) distance from the shield to the source; 2) desired weekly equivalent dose; 3) weekly total dose equivalent emitted by the equipment; 4) occupation and use factors. Once obtained thicknesses, we proceeded to model the bunker using the mentioned program. The program uses the Monte Carlo code to probabilistic ally determine the phenomena of interaction of radiation with the shield, which will be held during the X-ray emission from the linear accelerator. The results of computational analysis were compared with those obtained experimentally with the detection method, for which was required the use of a Geiger-Muller counter and the linear accelerator was programmed with an energy of 19 MV with 500 units monitor positioning the detector in the corresponding boundary. (Author)

  14. Erythropoietin and radiotherapy; Erythropoietine et radiotherapie

    Energy Technology Data Exchange (ETDEWEB)

    Le Fur, E.; Albarghach, M.N.; Pradier, O. [CHU de Morvan, Dept. de radiotherapie, 29 - Brest (France)

    2010-01-15

    Erythropoietin (E.P.O.) is a glycoprotein hormone. This hormone is a growth factor for red blood cells precursors in the bone marrow. The decrease of oxygen partial pressure, a reduced number of erythrocytes caused by bleeding or excessive destruction, or increased tissues oxygen requirements lead to increased secretion of E.P.O.. Its action takes place on bone marrow erythroblastic cells through specific receptors. E.P.O. stimulates the proliferation of red cell precursors stem cells in the bone marrow, thus increasing their production in one to two weeks. The effectiveness of E.P.O. at increasing haemoglobin and improving patients quality of life has been demonstrated by several studies. However, its use in radiotherapy remains controversial. While tumour hypoxia caused by anaemia is a factor of radio resistance and thus a source of local failure, tumour expression of E.P.O. receptors presents a significant risk for tumour progression and neo-angiogenesis, which would be increased during the administration of E.P.O.. The purpose of this article is to answer the question: is there a place for E.P.O. in combination with radiotherapy in the management of cancer?

  15. Towards MRI-guided radiotherapy in early-stage breast cancer patients

    NARCIS (Netherlands)

    Hartogh, M.D. den

    2014-01-01

    At the Department of Radiation Oncology of the UMC Utrecht, an MRI-linear accelerator (MRI-linac) is being developed. This hybrid MRI radiotherapy system features an 8 MV linear accelerator rotating around a 1.5 T cylindrical MRI scanner. This combination enables direct visualization of the radiothe

  16. Towards MRI-guided radiotherapy in early-stage breast cancer patients

    NARCIS (Netherlands)

    Hartogh, M.D. den

    2014-01-01

    At the Department of Radiation Oncology of the UMC Utrecht, an MRI-linear accelerator (MRI-linac) is being developed. This hybrid MRI radiotherapy system features an 8 MV linear accelerator rotating around a 1.5 T cylindrical MRI scanner. This combination enables direct visualization of the

  17. Innovations in Radiotherapy Technology.

    Science.gov (United States)

    Feain, I J; Court, L; Palta, J R; Beddar, S; Keall, P

    2017-02-01

    Many low- and middle-income countries, together with remote and low socioeconomic populations within high-income countries, lack the resources and services to deal with cancer. The challenges in upgrading or introducing the necessary services are enormous, from screening and diagnosis to radiotherapy planning/treatment and quality assurance. There are severe shortages not only in equipment, but also in the capacity to train, recruit and retain staff as well as in their ongoing professional development via effective international peer-review and collaboration. Here we describe some examples of emerging technology innovations based on real-time software and cloud-based capabilities that have the potential to redress some of these areas. These include: (i) automatic treatment planning to reduce physics staffing shortages, (ii) real-time image-guided adaptive radiotherapy technologies, (iii) fixed-beam radiotherapy treatment units that use patient (rather than gantry) rotation to reduce infrastructure costs and staff-to-patient ratios, (iv) cloud-based infrastructure programmes to facilitate international collaboration and quality assurance and (v) high dose rate mobile cobalt brachytherapy techniques for intraoperative radiotherapy. Copyright © 2016 The Royal College of Radiologists. All rights reserved.

  18. Radiotherapy for craniopharyngioma.

    Science.gov (United States)

    Aggarwal, Ajay; Fersht, Naomi; Brada, Michael

    2013-03-01

    Radiotherapy remains the mainstay of multidisciplinary management of patients with incompletely resected and recurrent craniopharyngioma. Advances in imaging and radiotherapy technology offer new alternatives with the principal aim of improving the accuracy of treatment and reducing the volume of normal brain receiving significant radiation doses. We review the available technologies, their technical advantages and disadvantages and the published clinical results. Fractionated high precision conformal radiotherapy with image guidance remains the gold standard; the results of single fraction treatment are disappointing and hypofractionation should be used with caution as long term results are not available. There is insufficient data on the use of protons to assess the comparative efficacy and toxicity. The precision of treatment delivery needs to be coupled with experienced infrastructure and more intensive quality assurance to ensure best treatment outcome and this should be carried out within multidisciplinary teams experienced in the management of craniopharyngioma. The advantages of the combined skills and expertise of the team members may outweigh the largely undefined clinical gain from novel radiotherapy technologies.

  19. A beam-matching concept for medical linear accelerators

    DEFF Research Database (Denmark)

    Sjöström, David; Bjelkengren, Ulf; Ottosson, Wiviann

    2009-01-01

    The flexibility in radiotherapy can be improved if a patient can be moved between any one of the department's medical linear accelerators without the need to change anything in the patient's treatment plan. For this to be possible, the dosimetric characteristics of the various accelerators must...

  20. Design and performance criteria for medical electron accelerators

    Science.gov (United States)

    Nunan, Craig S.

    1985-05-01

    A brief comparison is made of the design and performance of early and modern isocentric microwave linear accelerators for radiotherapy. Generally accepted criteria for the design of current machines are presented, along with a rationale for their selection. The current development of international standards for safety and performance of medical electron accelerators is reviewed.

  1. Future accelerators (?)

    Energy Technology Data Exchange (ETDEWEB)

    John Womersley

    2003-08-21

    I describe the future accelerator facilities that are currently foreseen for electroweak scale physics, neutrino physics, and nuclear structure. I will explore the physics justification for these machines, and suggest how the case for future accelerators can be made.

  2. Calculation of the structural shielding of the radiotherapy treatment room equipped with a linear accelerator type Tomo therapy Hi-Art in the Oncology Center of Chihuahua, Mexico; Calculo del blindaje estructural de la sala de tratamiento de radioterapia equipada con un acelerador lineal del tipo Tomotherapy Hi-Art en el Centro Oncologico de Chihuahua, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Caballero G, C. A. [Southwest Oncology Centers, North Civic Center Plaza No. 2926, Scottsdale, Arizona (United States); Plascencia, J. C. [Centro Oncologico Louis and Lucille Grado, Republica del Peru No. 102-5, Col. Americas, Aguascalientes (Mexico); Vargas V, M. X.; Toledo J, P., E-mail: cabshm@msn.co [Centro Oncologico de Chihuahua, Hacienda de la Esperanza No. 6304, Fracc. Cima Comercial, Chihuahua (Mexico)

    2010-09-15

    The helicoid tomo therapy is an external radiotherapy system of modulated intensity, guided by image, in which the radiation is imparted to the patient using a narrow radiation beam in helicoid form, in a similar way to the scanning process with a computerized tomography. The tomo therapy equipment (Tomo Therapy Hi-Art) consists in an electrons linear accelerator with acceleration voltages of 6 MV for treatment and 3.5 MV for image, coupled to a ring that turn around the patient as this is transferred through this ring in perpendicular sense to the radiation beam. The radiation beam is narrow because has the maximum size of 5 x 40 cm{sup 2} in the isocenter. The intensity modulation of the beam is carried out with a binary dynamic collimator of 64 crisscross sheets, and the guide by image though a system of megavoltage computerized tomography. Opposed to the radiation beam, also coupled to the rotational ring, a group of lead plates exists with a total thickness of 13 cm that acts as barrier of the primary radiation beam. The special configuration of the tomography equipment makes to have the following characteristics: 1) the presence of the lead barrier of the equipment reduces the intensity of the primary beam that reaches the bunker walls in considerable way, 2) the disperse and leakage radiations are increased with regard to a conventional accelerator due to the increase in the necessary irradiation time to produce modulated intensity fields by means of the narrow radiation beam. These special characteristics of the tomo therapy equipment make that particularities exist in the application of the formulations for structural shielding calculations that appears in the NCRP reports 49, NCRP 151 and IAEA-SRS-47. For this reason, several researches have development analytic models based on geometric considerations of continuous rotation of the equipment ring to determine the shielding requirements for the primary beam, the dispersed and leakage radiation in tomo

  3. [Radiotherapy for Graves' ophthalmopathy].

    Science.gov (United States)

    Kuhnt, T; Müller, A C; Janich, M; Gerlach, R; Hädecke, J; Duncker, G I W; Dunst, J

    2004-11-01

    Graves' ophthalmopathy (GO) is the most frequent extrathyroidal manifestation of Graves' disease, an autoimmune disorder of the thyroid, whereas the precise pathogenesis still remains unclear. In Hashimoto's thyroiditis the occurrence of proptosis is an extremely rare event. The therapy for middle and severe courses of GO shows in partly disappointing results, although several therapy modalities are possible (glucocorticoid therapy, radiotherapy, antithyroid drug treatment, surgery). All these therapies lead in only 40 - 70 % to an improvement of the pathogenic symptoms. An intensive interdisciplinary cooperation is necessary to satisfy the requirements for the treatment of Graves' ophthalmopathy. As a consequence of the very different results of the few of clinical studies that were accomplished with reference to this topic, treatment by radiotherapy in the management of the disease is presently controversially discussed. In the German-speaking countries the radiotherapy is, however, firmly established as a therapy option in the treatment of the moderate disease classes (class 2-5 according to NO SPECS), especially if diplopia is present. This article describes the sequences, dosages and fractionation schemes as well as the risks and side effects of the radiotherapy. Altogether, radiotherapy is assessed as an effective and sure method. The administration of glucocorticoids can take place before the beginning of or during the radiotherapy. For the success of treatment the correct selection of patients who may possibly profit from a radiotherapy is absolutely essential. By realising that GO proceeds normally over a period of 2-5 years, which is followed by a period of fibrotic alteration, the application of the radiotherapy in the early, active phase is indispensable. A precise explanation for the effects of radiotherapy in treatment of the GO does not exist at present. The determination of the most effective irradiation doses was made from retrospectively evaluated

  4. The physics of radiotherapy X-rays and electrons

    CERN Document Server

    Metcalfe, Peter; Hoban, Peter

    2012-01-01

    The Physics of Radiotherapy X-Rays and Electrons is an updated successor to The Physics of Radiotherapy X-Rays from Linear Accelerators published in 1997. This new volume includes a significant amount of new material, including new chapters on electrons in radiotherapy and IMRT, IGRT, and tomotherapy, which have become key developments in radiation therapy. Also updated from the earlier edition are the physics beam modeling chapters, including Monte Carlo methods, adding those mysterious electrons, as well as discourse on radiobiological modeling including TCP, NTCP, and EUD and the impact of these concepts on plan analysis and inverse planning. This book is intended as a standard reference text for postgraduate radiation oncology medical physics students. It will also be of interest to radiation oncology registrars and residents, dosimetrists, and radiation therapists. The new text contains review questions at the end of each chapter and full bibliographic entries. Fully indexed. Selected questions and ans...

  5. Radiotherapy of cutaneous lymphomas; Radiotherapie des lymphomes cutanes

    Energy Technology Data Exchange (ETDEWEB)

    Kirova, Y.M.; Piedbois, Y.; Pan, Q.; Guo, J.P.; Le Bourgeois, J.P. [Hopital Henri-Mondor, 94 - Creteil (France). Dept. de cancerologie

    1999-03-01

    Radiotherapy plays an important role in the treatment of cutaneous lymphomas. In the treatment of Mycosis fungoides, total skin electron beam radiation therapy is efficient for patients with limited and superficial forms of the disease. Radiotherapy is also efficient for the locally advanced forms of non-epidermo-tropic lymphomas. The palliative radiotherapy is indicated for advanced, nodular and treatment resistant forms of cutaneous lymphomas and for voluminous lymphadenopathies. (authors)

  6. Design of the Intelligent Instruments Online Monitoring System Based on Wireless HART%基于无线HART的智能仪表在线监控系统

    Institute of Scientific and Technical Information of China (English)

    高晋树; 王洪元; 潘操; 刘晓宇

    2011-01-01

    为了充分利用传统HART仪表,提高控制系统的可靠性,减少现场仪表的维护量并降低维护费用,提出了一种基于无线HART协议的智能仪表在线监控系统,给出了系统的软、硬件设计思想和实现方法.%Considering the well-application of traditional HART instruments, and enhancing control system reliability and reducing field instruments maintenance and service costs, an on-line monitoring system based on wireless HART protocol for intelligent instruments was proposed, including the introduction of system architecture and design idea and implement method.

  7. Radiotherapy of hemangiomas

    Energy Technology Data Exchange (ETDEWEB)

    Gauwerky, F.

    1982-10-11

    The findings about the regular, spontaneous and complete regression of cavernous skin hemangiomas occurring in infants and those findings about the damaging effects due to ionising radiation - here particularly local growth disturbances - led to the development of very cautious diagnostic methods and to a considerate individual dosage and radiotherapy, which always takes into consideration the spontaneous regression tendency of the hemangiomas. However, a function-impairing localisation at the orifices, fulminant macrosomia, tendency to hemorrhages and poly-infection with superficial ulceration and even thrombopenic syndromes of the Kasabach-Merritt type may become necessary, urgent and also vital indications for a particular radiotherapy. For the sake of the patients, irradiation methods, which do not provoke any risk of radiation hazards, have to be preserved and applied in practice. Certainly further research and the nosologic nature of hemangiomas is required. A general non-treatment of hemangiomas is refused.

  8. The application of the HT2012 HART○R Modem to the HART protocol%HT2012 HART○RModem在HART协议中的应用

    Institute of Scientific and Technical Information of China (English)

    蔡立虹; 庞彦斌

    2001-01-01

    本文介绍了SMAR公司的HT2012 HART○RModem芯片的特点与功能以及在HART协议物理层中的应用%This paper presents the features and the functions of the Smar HT2012 HART○R Modem and also describes the application of the HT2012 chip to the physical layer of the HART protocol.

  9. Melanoma: Last call for radiotherapy.

    Science.gov (United States)

    Espenel, Sophie; Vallard, Alexis; Rancoule, Chloé; Garcia, Max-Adrien; Guy, Jean-Baptiste; Chargari, Cyrus; Deutsch, Eric; Magné, Nicolas

    2017-02-01

    Melanoma is traditionally considered to be a radioresistant tumor. However, radiotherapy and immunotherapy latest developments might upset this radiobiological dogma. Stereotactic radiotherapy allows high dose per fraction delivery, with high dose rate. More DNA lethal damages, less sublethal damages reparation, endothelial cell apoptosis, and finally clonogenic cell dysfunction are produced, resulting in improved local control. Radiotherapy can also enhance immune responses, inducing neoantigens formation, tumor antigen presentation, and cytokines release. A synergic effect of radiotherapy with immunotherapy is expected, and might lead to abscopal effects. If hadrontherapy biological properties seem able to suppress hypoxia-induced radioresistance and increase biological efficacy, ballistic advantages over photon radiations might also improve radiotherapy outcomes on usually poor prognosis locations. The present review addresses biological and clinical effects of high fraction dose, bystander effect, abscopal effect, and hadrontherapy features in melanoma. Clinical trials results are warranted to establish indications of innovative radiotherapy in melanoma.

  10. Radiotherapy of vertebral hemangiomas

    Energy Technology Data Exchange (ETDEWEB)

    Sakata, Kohichi; Hareyama, Masato; Oouchi, Atushi; Sido, Mitsuo; Nagakura, Hisayasu; Tamakawa, Mituharu; Akiba, Hidenari; Morita, Kazuo [Dept. of Radiology, Sapporo Medical Univ., School of Medicine (Japan)

    1997-12-31

    Between 1975 and 1996, 14 patients (11 females, 3 males) with vertebral hemangioma received treatment with radiotherapy. Thirteen patients had a history of back pain or lumbago and 2 patients had neurological symptoms such as sensory impairment or paraplegia. The standard dose administered was 36 Gy in 18 fractions (five treatments per week). In the 13 patients with pain, this was completely or partially relieved. The condition of a man with hypesthesia of the legs deteriorated and a woman with paraplegia who was treated with decompressive laminectomy followed by radiotherapy recovered completely after irradiation. CT scan before irradiation showed thickened trabeculae as small punctate areas of sclerosis in all patients. At MR imaging before irradiation, T2-weighted MR images showed areas of high intensity in all patients and MR images demonstrated lesion enhancement. However, none of the patients who were treated successfully with radiation demonstrated any changes of the affected vertebra in the conventional radiographic films, CT scan or MR imaging, even 5 years after irradiation. Radiological imaging is indispensable for the diagnosis of vertebral hemangiomas but does not appear to be useful for evaluating the effects of radiotherapy. (orig.).

  11. Accelerating Value Creation with Accelerators

    DEFF Research Database (Denmark)

    Jonsson, Eythor Ivar

    2015-01-01

    accelerator programs. Microsoft runs accelerators in seven different countries. Accelerators have grown out of the infancy stage and are now an accepted approach to develop new ventures based on cutting-edge technology like the internet of things, mobile technology, big data and virtual reality. It is also...... with the traditional audit and legal universes and industries are examples of emerging potentials both from a research and business point of view to exploit and explore further. The accelerator approach may therefore be an Idea Watch to consider, no matter which industry you are in, because in essence accelerators...

  12. Radiotherapy physics research in the UK: challenges and proposed solutions.

    Science.gov (United States)

    Mackay, R I; Burnet, N G; Green, S; Illidge, T M; Staffurth, J N

    2012-10-01

    In 2011, the Clinical and Translational Radiotherapy Research Working Group (CTRad) of the National Cancer Research Institute brought together UK radiotherapy physics leaders for a think tank meeting. Following a format that CTRad had previously and successfully used with clinical oncologists, 23 departments were asked to complete a pre-meeting evaluation of their radiotherapy physics research infrastructure and the strengths, weaknesses, opportunities and threats within their own centre. These departments were brought together with the CTRad Executive Group and research funders to discuss the current state of radiotherapy physics research, perceived barriers and possible solutions. In this Commentary, we summarise the submitted materials, presentations and discussions from the meeting and propose an action plan. It is clear that there are challenges in both funding and staffing of radiotherapy physics research. Programme and project funding streams sometimes struggle to cater for physics-led work, and increased representation on research funding bodies would be valuable. Career paths for academic radiotherapy physicists need to be examined and an academic training route identified within Modernising Scientific Careers; the introduction of formal job plans may allow greater protection of research time, and should be considered. Improved access to research facilities, including research linear accelerators, would enhance research activity and pass on developments to patients more quickly; research infrastructure could be benchmarked against centres in the UK and abroad. UK National Health Service departments wishing to undertake radiotherapy research, with its attendant added value for patients, need to develop a strategy with their partner higher education institution, and collaboration between departments may provide enhanced opportunities for funded research.

  13. A Investigation of Radiotherapy Electron Beams Using Monte Carlo Techniques

    Science.gov (United States)

    Ding, George X.

    1995-01-01

    Radiotherapy electron beams are more complicated than photon beams due to variations in the beam production, the scattering of low-energy electrons, and the presence contaminant photons. The detailed knowledge of a radiotherapy beam is essential to an accurate calculation of dose distribution for a treatment planning system. This investigation aims to enhance our understanding of radiotherapy beams by focusing on electron beams used in radiotherapy. It starts with a description of the Monte Carlo simulation code, BEAM, and a detailed simulation of an accelerator head to obtain realistic radiotherapy beams. The simulation covers electron beams from various accelerators, including the NRC research accelerator, the NPL (UK), accelerator, A Varian Clinac 2100C, a Philips SL75-20, a Siemens KD2, an AECL Therac 20, and a Scanditronix MM50. The beam energies range from 4 to 50 MeV. The EGS4 user code, BEAM, is extensively benchmarked against experiment by comparing calculated dose distributions with measured dose distributions in water. The simulated beams are analyzed to obtain the characteristics of various electron beams from a variety of accelerators. The simulated beams are also used as inputs to calculate the following parameters: the mean electron energy, the most probable energy, the energy-range relationships, the depth-scaling factor to convert depths in plastic to water-equivalent depths, the water-to-air stopping-power ratios, and the electron fluence correction factors used to convert dose measured in plastics to dose in water. These parameters are essential for electron beam dosimetry. The results from this study can be applied in cancer clinics to improve the accuracy of the absolute dosimetry. The simulation also provides information about the backscatter into the beam monitor chamber, and predicts the influence on the beam output factors. This investigation presents comprehensive data on the clinical electron beams, and answers many questions which could

  14. Dosimetry at the location of secondary tumors after radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Baas, H.W.; Davelaar, J.J.; Broerse, J.J.; Noordijk, E.M. [University Hospital, Leiden (Netherlands). Dept. of Clinical Oncology

    1995-12-01

    After a latency period of many years the incidence of a secondary tumor is considered a serious late effect of radiotherapy. Analysis of about 200 patients, treated by radiotherapy for Hodgkin`s disease in our hospital, shows an actuarial risk for the incidence of a secondary tumor of about 7% after 10 years. The chance of tumor induction depends on the dose at the location of the tumor and therefore a good dose estimation is mandatory. Radiotherapy was given with Co-60 in the early years and with linear accelerators thereafter, exposing the target areas to 36 - 40 Gy. For dose estimations at the penumbra and outside the beam, where tumor incidence is expected to be high, we used a.o. Monte Carlo calculations. We developed an EGS4 computer simulation for a treatment beam from a linear accelerator irradiating a mathematical phantom representing the patient geometry (GSF ADAM phantom). The isodose curves at certain energies were obtained for a water phantom and fitted quite well with measurements. In addition to Monte Carlo calculations we also used existing treatment planning systems. The dose estimations of a number of patients and the derived risk per unit of dose, which is important for both radiotherapy as well as radiation protection in general, is discussed.

  15. Accelerating Value Creation with Accelerators

    DEFF Research Database (Denmark)

    Jonsson, Eythor Ivar

    2015-01-01

    Accelerators can help to accelerate value creation. Accelerators are short-term programs that have the objective of creating innovative and fast growing ventures. They have gained attraction as larger corporations like Microsoft, Barclays bank and Nordea bank have initiated and sponsored accelera......Accelerators can help to accelerate value creation. Accelerators are short-term programs that have the objective of creating innovative and fast growing ventures. They have gained attraction as larger corporations like Microsoft, Barclays bank and Nordea bank have initiated and sponsored...... an approach to facilitate implementation and realization of business ideas and is a lucrative approach to transform research into ventures and to revitalize regions and industries in transition. Investors have noticed that the accelerator approach is a way to increase the possibility of success by funnelling...

  16. 基于HART协议的pH分析仪%pH Analyzer Design Based on HART Protocol

    Institute of Scientific and Technical Information of China (English)

    王军; 黄皎; 吴穹; 雷鸣; 卢程

    2013-01-01

    A HART principle-based pH analyzer was designed,in which,both pH electrode sensor and temperature sensor can measure pH ion concentration,and the real-time data can be sent to the remote terminal through A/D conversion and MCU processing;C ++ Builder 6 was used to produce man-machine interface of the host computer for remote monitoring,and the interface of host computer connected to the database can save the real-time data and facilitate both data query and historical data analysis.%介绍基于HART原理的新型pH分析仪的设计方法,由pH电极传感器和温度传感器测量H+浓度,经A/D转换和MCU的分析处理,将实时数据经由HART接口发送至远程终端;运用C++Builder 6制作上位机人机界面,实现远程监控;上位机界面与数据库相连,实现实时数据的存储,方便用户查询并分析历史数据.

  17. The HART II International Workshop: An Assessment of the State-of-the-Art in Comprehensive Code Prediction

    Science.gov (United States)

    vanderWall, Berend G.; Lim, Joon W.; Smith, Marilyn J.; Jung, Sung N.; Bailly, Joelle; Baeder, James D.; Boyd, D. Douglas, Jr.

    2013-01-01

    Significant advancements in computational fluid dynamics (CFD) and their coupling with computational structural dynamics (CSD, or comprehensive codes) for rotorcraft applications have been achieved recently. Despite this, CSD codes with their engineering level of modeling the rotor blade dynamics, the unsteady sectional aerodynamics and the vortical wake are still the workhorse for the majority of applications. This is especially true when a large number of parameter variations is to be performed and their impact on performance, structural loads, vibration and noise is to be judged in an approximate yet reliable and as accurate as possible manner. In this article, the capabilities of such codes are evaluated using the HART II International Workshop database, focusing on a typical descent operating condition which includes strong blade-vortex interactions. A companion article addresses the CFD/CSD coupled approach. Three cases are of interest: the baseline case and two cases with 3/rev higher harmonic blade root pitch control (HHC) with different control phases employed. One setting is for minimum blade-vortex interaction noise radiation and the other one for minimum vibration generation. The challenge is to correctly predict the wake physics-especially for the cases with HHC-and all the dynamics, aerodynamics, modifications of the wake structure and the aero-acoustics coming with it. It is observed that the comprehensive codes used today have a surprisingly good predictive capability when they appropriately account for all of the physics involved. The minimum requirements to obtain these results are outlined.

  18. Rotor Wake Vortex Definition: Initial Evaluation of 3-C PIV Results of the Hart-II Study

    Science.gov (United States)

    Burley, Casey L.; Brooks, Thomas F.; vanderWall, Berend; Richard, Hughes; Raffel, Markus; Beaumier, Philippe; Delrieux, Yves; Lim, Joon W.; Yu, Yung H.; Tung, Chee

    2002-01-01

    An initial evaluation is made of extensive three-component (3C) particle image velocimetry (PIV) measurements within the wake across a rotor disk plane. The model is a 40 percent scale BO-105 helicopter main rotor in forward flight simulation. This study is part of the HART II test program conducted in the German-Dutch Wind Tunnel (DNW). Included are wake vortex field measurements over the advancing and retreating sides of the rotor operating at a typical descent landing condition important for impulsive blade-vortex interaction (BVI) noise. Also included are advancing side results for rotor angle variations from climb to steep descent. Using detailed PIV vector maps of the vortex fields, methods of extracting key vortex parameters are examined and a new method was developed and evaluated. An objective processing method, involving a center-of-vorticity criterion and a vorticity 'disk' integration, was used to determine vortex core size, strength, core velocity distribution characteristics, and unsteadiness. These parameters are mapped over the rotor disk and offer unique physical insight for these parameters of importance for rotor noise and vibration prediction.

  19. An Assessment of CFD/CSD Prediction State-of-the-Art by Using the HART II International Workshop Data

    Science.gov (United States)

    Smith, Marilyn J.; Lim, Joon W.; vanderWall, Berend G.; Baeder, James D.; Biedron, Robert T.; Boyd, D. Douglas, Jr.; Jayaraman, Buvana; Jung, Sung N.; Min, Byung-Young

    2012-01-01

    Over the past decade, there have been significant advancements in the accuracy of rotor aeroelastic simulations with the application of computational fluid dynamics methods coupled with computational structural dynamics codes (CFD/CSD). The HART II International Workshop database, which includes descent operating conditions with strong blade-vortex interactions (BVI), provides a unique opportunity to assess the ability of CFD/CSD to capture these physics. In addition to a baseline case with BVI, two additional cases with 3/rev higher harmonic blade root pitch control (HHC) are available for comparison. The collaboration during the workshop permits assessment of structured, unstructured, and hybrid overset CFD/CSD methods from across the globe on the dynamics, aerodynamics, and wake structure. Evaluation of the plethora of CFD/CSD methods indicate that the most important numerical variables associated with most accurately capturing BVI are a two-equation or detached eddy simulation (DES)-based turbulence model and a sufficiently small time step. An appropriate trade-off between grid fidelity and spatial accuracy schemes also appears to be pertinent for capturing BVI on the advancing rotor disk. Overall, the CFD/CSD methods generally fall within the same accuracy; cost-effective hybrid Navier-Stokes/Lagrangian wake methods provide accuracies within 50% the full CFD/CSD methods for most parameters of interest, except for those highly influenced by torsion. The importance of modeling the fuselage is observed, and other computational requirements are discussed.

  20. Robert Hart and Modern Chinese Postal Service%赫德与中国近代邮政

    Institute of Scientific and Technical Information of China (English)

    贾熟村

    2012-01-01

    In modern times, imperialist powers launched many wars of aggression and forced the Qing Government to sign a series of treaties of inequality, listing Shanghai and other cities as trading ports. In those areas, those countries encroached upon Chinese sovereignty, set up post offices and provided postal service. Robert Hart, in order to save Chinese sovereignty, struggled with those powers on just grounds, to China' s benefit and with restraint, and made important contributions to modern Chinese postal industry.%中国近代,列强多次发动侵华战争,迫使清政府签订了一系列不平等条约,规定上海等几十个地区为通商口岸。列强在这些地区侵犯中国主权,开设邮局,经营邮递业务。赫德为挽回中国主权,与列强进行了长期的有理、有利、有节的抗争,使中国近代邮政从无到有,从小到大,作出一重要贡献,功不可没。

  1. A comparative study on the risk of second primary cancers in out-of-field organs associated with radiotherapy of localized prostate carcinoma using Monte Carlo-based accelerator and patient models

    Energy Technology Data Exchange (ETDEWEB)

    Bednarz, Bryan; Athar, Basit; Xu, X. George [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02108 and Department of Mechanical Aerospace and Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States)

    2010-05-15

    Purpose: A physician's decision regarding an ideal treatment approach (i.e., radiation, surgery, and/or hormonal) for prostate carcinoma is traditionally based on a variety of metrics. One of these metrics is the risk of radiation-induced second primary cancer following radiation treatments. The aim of this study was to investigate the significance of second cancer risks in out-of-field organs from 3D-CRT and IMRT treatments of prostate carcinoma compared to baseline cancer risks in these organs. Methods: Monte Carlo simulations were performed using a detailed medical linear accelerator model and an anatomically realistic adult male whole-body phantom. A four-field box treatment, a four-field box treatment plus a six-field boost, and a seven-field IMRT treatment were simulated. Using BEIR VII risk models, the age-dependent lifetime attributable risks to various organs outside the primary beam with a known predilection for cancer were calculated using organ-averaged equivalent doses. Results: The four-field box treatment had the lowest treatment-related second primary cancer risks to organs outside the primary beam ranging from 7.3x10{sup -9} to 2.54x10{sup -5}%/MU depending on the patients age at exposure and second primary cancer site. The risks to organs outside the primary beam from the four-field box and six-field boost and the seven-field IMRT were nearly equivalent. The risks from the four-field box and six-field boost ranged from 1.39x10{sup -8} to 1.80x10{sup -5}%/MU, and from the seven-field IMRT ranged from 1.60x10{sup -9} to 1.35x10{sup -5}%/MU. The second cancer risks in all organs considered from each plan were below the baseline risks. Conclusions: The treatment-related second cancer risks in organs outside the primary beam due to 3D-CRT and IMRT is small. New risk assessment techniques need to be investigated to address the concern of radiation-induced second cancers from prostate treatments, particularly focusing on risks to organs inside the

  2. A comparative study on the risk of second primary cancers in out-of-field organs associated with radiotherapy of localized prostate carcinoma using Monte Carlo-based accelerator and patient models

    Science.gov (United States)

    Bednarz, Bryan; Athar, Basit; Xu, X. George

    2010-01-01

    Purpose: A physician’s decision regarding an ideal treatment approach (i.e., radiation, surgery, and∕or hormonal) for prostate carcinoma is traditionally based on a variety of metrics. One of these metrics is the risk of radiation-induced second primary cancer following radiation treatments. The aim of this study was to investigate the significance of second cancer risks in out-of-field organs from 3D-CRT and IMRT treatments of prostate carcinoma compared to baseline cancer risks in these organs. Methods: Monte Carlo simulations were performed using a detailed medical linear accelerator model and an anatomically realistic adult male whole-body phantom. A four-field box treatment, a four-field box treatment plus a six-field boost, and a seven-field IMRT treatment were simulated. Using BEIR VII risk models, the age-dependent lifetime attributable risks to various organs outside the primary beam with a known predilection for cancer were calculated using organ-averaged equivalent doses. Results: The four-field box treatment had the lowest treatment-related second primary cancer risks to organs outside the primary beam ranging from 7.3×10−9 to 2.54×10−5%∕MU depending on the patients age at exposure and second primary cancer site. The risks to organs outside the primary beam from the four-field box and six-field boost and the seven-field IMRT were nearly equivalent. The risks from the four-field box and six-field boost ranged from 1.39×10−8 to 1.80×10−5%∕MU, and from the seven-field IMRT ranged from 1.60×10−9 to 1.35×10−5%∕MU. The second cancer risks in all organs considered from each plan were below the baseline risks. Conclusions: The treatment-related second cancer risks in organs outside the primary beam due to 3D-CRT and IMRT is small. New risk assessment techniques need to be investigated to address the concern of radiation-induced second cancers from prostate treatments, particularly focusing on risks to organs inside the primary beam

  3. Project of compact accelerator for cancer proton therapy; Progetto di acceleratore compatto per terapia oncologica con protoni (TOP)

    Energy Technology Data Exchange (ETDEWEB)

    Picardi, L.; Ronsivalle, C.; Vignati, A. [ENEA, Cntro Ricerche Frascati, Rome (Italy). Dip. Innovazione

    1995-04-01

    The status of the sub-project `Compact Accelerator` in the framework of the Hadrontherapy Project leaded by Prof. Amaldi is described. Emphasis is given to the reasons of the use of protons for radiotherapy applications, to the results of the preliminary design studies of four types of accelerators as possible radiotherapy dedicated `Compact Accelerator` and to the scenario of the fonts of financial resources.

  4. Tracing sources of crustal contamination using multiple S and Fe isotopes in the Hart komatiite-associated Ni-Cu-PGE sulfide deposit, Abitibi greenstone belt, Ontario, Canada

    Science.gov (United States)

    Hiebert, R. S.; Bekker, A.; Houlé, M. G.; Wing, B. A.; Rouxel, O. J.

    2016-10-01

    Assimilation by mafic to ultramafic magmas of sulfur-bearing country rocks is considered an important contributing factor to reach sulfide saturation and form magmatic Ni-Cu-platinum group element (PGE) sulfide deposits. Sulfur-bearing sedimentary rocks in the Archean are generally characterized by mass-independent fractionation of sulfur isotopes that is a result of atmospheric photochemical reactions, which produces isotopically distinct pools of sulfur. Likewise, low-temperature processing of iron, through biological and abiotic redox cycling, produces a range of Fe isotope values in Archean sedimentary rocks that is distinct from the range of the mantle and magmatic Fe isotope values. Both of these signals can be used to identify potential country rock assimilants and their contribution to magmatic sulfide deposits. We use multiple S and Fe isotopes to characterize the composition of the potential iron and sulfur sources for the sulfide liquids that formed the Hart deposit in the Shaw Dome area within the Abitibi greenstone belt in Ontario (Canada). The Hart deposit is composed of two zones with komatiite-associated Ni-Cu-PGE mineralization; the main zone consists of a massive sulfide deposit at the base of the basal flow in the komatiite sequence, whereas the eastern extension consists of a semi-massive sulfide zone located 12 to 25 m above the base of the second flow in the komatiite sequence. Low δ56Fe values and non-zero δ34S and Δ33S values of the komatiitic rocks and associated mineralization at the Hart deposit is best explained by mixing and isotope exchange with crustal materials, such as exhalite and graphitic argillite, rather than intrinsic fractionation within the komatiite. This approach allows tracing the extent of crustal contamination away from the deposit and the degree of mixing between the sulfide and komatiite melts. The exhalite and graphitic argillite were the dominant contaminants for the main zone of mineralization and the eastern

  5. TECHNOLOGIES FOR DELIVERY OF PROTON AND ION BEAMS FOR RADIOTHERAPY

    CERN Document Server

    Owen, H; Alonso, J; Mackay, R

    2014-01-01

    Recent developments for the delivery of proton and ion beam therapy have been significant, and a number of technological solutions now exist for the creation and utilisation of these particles for the treatment of cancer. In this paper we review the historical development of particle accelerators used for external beam radiotherapy and discuss the more recent progress towards more capable and cost-effective sources of particles.

  6. Technologies for Delivery of Proton and Ion Beams for Radiotherapy

    CERN Document Server

    Owen, Hywel; Alonso, Jose; MacKay, Ranald

    2013-01-01

    Recent developments for the delivery of proton and ion beam therapy have been significant, and a number of technological solutions now exist for the creation and utilisation of these particles for the treatment of cancer. In this paper we review the historical development of particle accelerators used for external beam radiotherapy and discuss the more recent progress towards more capable and cost-effective sources of particles.

  7. Monte Carlo radiation transport in external beam radiotherapy

    OpenAIRE

    Çeçen, Yiğit

    2013-01-01

    The use of Monte Carlo in radiation transport is an effective way to predict absorbed dose distributions. Monte Carlo modeling has contributed to a better understanding of photon and electron transport by radiotherapy physicists. The aim of this review is to introduce Monte Carlo as a powerful radiation transport tool. In this review, photon and electron transport algorithms for Monte Carlo techniques are investigated and a clinical linear accelerator model is studied for external beam radiot...

  8. Characteristic evaluation of photoneutron in radiotherapy room using MCNPX

    Science.gov (United States)

    Park, E.-T.; Kim, J.-H.; Kim, C.-S.; Kang, S.-S.

    2015-08-01

    Linear accelerators are now playing a pivotal role in radiotherapy and high energy photon beams of a strength exceeding 8 MV have recently been mainly used. However, when using high energy photons, neutron contamination due to photonuclear reaction develops. This study focused on the dose distribution of photoneutrons emitted from a linear accelerator using Monte Carlo MCNPX code. MCNPX was used to simulate transportation of photoneutrons in the linear accelerator and the entire space of the radiotherapy room and is useful for calculating the flux, spectrum and absorbed dose. As result of the simulation, we could know that the neutron absorbed dose was as less as negligible when comparing to the photon absorbed dose in radiotherapy room. And it was found that the photoneutron flux increased substantially starting from 10 MV while the absorbed dose rose sharply between 10 MV and 12 MV. It was observed that although the ratio of thermal neutrons to fast neutrons was not altered as the energy increased, it was found that as the distance from the source increased the ratio of thermal neutrons rose markedly.

  9. RECIRCULATING ACCELERATION

    Energy Technology Data Exchange (ETDEWEB)

    BERG,J.S.; GARREN,A.A.; JOHNSTONE,C.

    2000-04-07

    This paper compares various types of recirculating accelerators, outlining the advantages and disadvantages of various approaches. The accelerators are characterized according to the types of arcs they use: whether there is a single arc for the entire recirculator or there are multiple arcs, and whether the arc(s) are isochronous or non-isochronous.

  10. LIBO accelerates

    CERN Multimedia

    2002-01-01

    The prototype module of LIBO, a linear accelerator project designed for cancer therapy, has passed its first proton-beam acceleration test. In parallel a new version - LIBO-30 - is being developed, which promises to open up even more interesting avenues.

  11. Plan optimization for stereotactic radiotherapy

    NARCIS (Netherlands)

    J.A. de Pooter (Jacobus Abraham)

    2008-01-01

    textabstractCancer is one of the leading causes of death in the world. Next to surgery and chemotherapy, radiotherapy is one of the most used treatment modalities for cancer. About 50% of the patients with cancer will be treated with radiotherapy during the management of their disease. In radiothera

  12. The Confluence of Radiotherapy & Immunotherapy

    Directory of Open Access Journals (Sweden)

    Ralph Robert Weichselbaum

    2012-10-01

    Full Text Available Radiotherapy has been considered a local modality and outcomes have emphasized local and regional control of tumors. Recent data suggests that radiotherapy may activate the immune system and the combination of radiation therapy and immune therapies may have the potential to improve both local and distant control of tumor deposits. Below we review principals underlying the concepts of combining both modalities.

  13. Bystander effects and radiotherapy.

    Science.gov (United States)

    Marín, Alicia; Martín, Margarita; Liñán, Olga; Alvarenga, Felipe; López, Mario; Fernández, Laura; Büchser, David; Cerezo, Laura

    2015-01-01

    Radiation-induced bystander effects are defined as biological effects expressed after irradiation by cells whose nuclei have not been directly irradiated. These effects include DNA damage, chromosomal instability, mutation, and apoptosis. There is considerable evidence that ionizing radiation affects cells located near the site of irradiation, which respond individually and collectively as part of a large interconnected web. These bystander signals can alter the dynamic equilibrium between proliferation, apoptosis, quiescence or differentiation. The aim of this review is to examine the most important biological effects of this phenomenon with regard to areas of major interest in radiotherapy. Such aspects include radiation-induced bystander effects during the cell cycle under hypoxic conditions when administering fractionated modalities or combined radio-chemotherapy. Other relevant aspects include individual variation and genetics in toxicity of bystander factors and normal tissue collateral damage. In advanced radiotherapy techniques, such as intensity-modulated radiation therapy (IMRT), the high degree of dose conformity to the target volume reduces the dose and, therefore, the risk of complications, to normal tissues. However, significant doses can accumulate out-of-field due to photon scattering and this may impact cellular response in these regions. Protons may offer a solution to reduce out-of-field doses. The bystander effect has numerous associated phenomena, including adaptive response, genomic instability, and abscopal effects. Also, the bystander effect can influence radiation protection and oxidative stress. It is essential that we understand the mechanisms underlying the bystander effect in order to more accurately assess radiation risk and to evaluate protocols for cancer radiotherapy.

  14. Accelerating Inspire

    CERN Document Server

    AUTHOR|(CDS)2266999

    2017-01-01

    CERN has been involved in the dissemination of scientific results since its early days and has continuously updated the distribution channels. Currently, Inspire hosts catalogues of articles, authors, institutions, conferences, jobs, experiments, journals and more. Successful orientation among this amount of data requires comprehensive linking between the content. Inspire has lacked a system for linking experiments and articles together based on which accelerator they were conducted at. The purpose of this project has been to create such a system. Records for 156 accelerators were created and all 2913 experiments on Inspire were given corresponding MARC tags. Records of 18404 accelerator physics related bibliographic entries were also tagged with corresponding accelerator tags. Finally, as a part of the endeavour to broaden CERN's presence on Wikipedia, existing Wikipedia articles of accelerators were updated with short descriptions and links to Inspire. In total, 86 Wikipedia articles were updated. This repo...

  15. Radiotherapy of benign diseases

    Energy Technology Data Exchange (ETDEWEB)

    Haase, W.

    1982-10-11

    Still today radiotherapy is of decisive relevance for several benign diseases. The following ones are briefly described in this introductory article: 1. Certain inflammatory and degenerative diseases as furuncles in the face, acute thrombophlebitis, recurrent pseudoriparous abscesses, degenerative skeletal diseases, cervical syndrome and others; 2. rheumatic joint diseases; 3. Bechterew's disease; 4. primary presenile osteoporosis; 5. syringomyelia; 6. endocrine ophthalmopathy; 7. hypertrophic processes of the connective tissue; 8. hemangiomas. A detailed discussion and a profit-risk analysis is provided in the individual chapters of the magazine.

  16. From image-guided radiotherapy to dose-guided radiotherapy; De la radiotherapie guidee par l'image a la radiotherapie guidee par la dose

    Energy Technology Data Exchange (ETDEWEB)

    Cazoulat, G.; Lesaunier, M.; Simon, A.; Haigron, P.; Acosta, O. [Inserm, U642, 35000 Rennes (France); LTSI, universite de Rennes-1, 35000 Rennes (France); Louvel, G.; Chajon, E.; Leseur, J. [Centre Eugene-Marquis, rue de La-Bataille-Flandres-Dunkerque, CS 44229, 35042 Rennes cedex (France); Lafond, C.; De Crevoisier, R. [Inserm, U642, 35000 Rennes (France); LTSI, universite de Rennes-1, 35000 Rennes (France); Centre Eugene-Marquis, rue de La-Bataille-Flandres-Dunkerque, CS 44229, 35042 Rennes cedex (France)

    2011-12-15

    Purpose. - In case of tumour displacement, image-guided radiotherapy (IGRT) based on the use of cone beam CT (tomographie conique) allows replacing the tumour under the accelerator by rigid registration. Anatomical deformations require however re-planning, involving an estimation of the cumulative dose, session after session. This is the objective of this study. Patients and methods. - Two examples of arc-intensity modulated radiotherapy are presented: a case of prostate cancer (total dose = 80 Gy) with tomographie conique (daily prostate registration) and one head and neck cancer (70 Gy). For the head and neck cancer, the patient had a weekly scanner allowing a dose distribution calculation. The cumulative dose was calculated per voxel on the planning CT after deformation of the dose distribution (with trilinear interpolation) following the transformation given by a non-rigid registration step (Demons registration method) from: either the tomographie conique (prostate), or the weekly CT. The cumulative dose was eventually compared with the planned dose. Results. - In cases of prostate irradiation, the 'cumulative' dose corresponded to the planned dose to the prostate. At the last week of irradiation, it was above the planned dose for the rectum and bladder. The volume of rectal wall receiving more than 50 Gy (V50) was 20% at the planning and 26% at the end of treatment, increasing the risk of rectal toxicity (NTCP) of 14%. For the bladder wall, V50 were 73% and 82%, respectively. In head and neck, the 'cumulative' dose to the parotid exceeded the planned dose (mean dose increasing from 46 Gy to 54 Gy) from the 5. week of irradiation on, suggesting the need for re-planning within the first 5 weeks of radiotherapy. Conclusion. - The deformable registration estimates the cumulative dose delivered in the different anatomical structures. Validation on digital and physical phantoms is however required before clinical evaluation. (authors)

  17. Proton minibeam radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Girst, Stefanie

    2016-03-08

    The risk of developing adverse side effects in the normal tissue after radiotherapy is often limiting for the dose that can be applied to the tumor. Proton minibeam radiotherapy, a spatially fractionated radiotherapy method using sub-millimeter proton beams, similar to grid therapy or microbeam radiation radiotherapy (MRT) using X-rays, has recently been invented at the ion microprobe SNAKE in Munich. The aim of this new concept is to minimize normal tissue injuries in the entrance channel and especially in the skin by irradiating only a small percentage of the cells in the total irradiation field, while maintaining tumor control via a homogeneous dose in the tumor, just like in conventional broad beam radiotherapy. This can be achieved by optimizing minibeam sizes and distances according to the prevailing tumor size and depth such that after widening of the minibeams due to proton interactions in the tissue, the overlapping minibeams produce a homogeneous dose distribution throughout the tumor. The aim of this work was to elucidate the prospects of minibeam radiation therapy compared to conventional homogeneous broad beam radiotherapy in theory and in experimental studies at the ion microprobe SNAKE. Treatment plans for model tumors of different sizes and depths were created using the planning software LAPCERR, to elaborate suitable minibeam sizes and distances for the individual tumors. Radiotherapy-relevant inter-beam distances required to obtain a homogeneous dose in the target volume were found to be in the millimeter range. First experiments using proton minibeams of only 10 μm and 50 μm size (termed microchannels in the corresponding publication Zlobinskaya et al. 2013) and therapy-conform larger dimensions of 100 μm and 180 μm were performed in the artificial human in-vitro skin model EpiDermFT trademark (MatTek). The corresponding inter-beam distances were 500 μm, 1mm and 1.8 mm, respectively, leading to irradiation of only a few percent of the cells

  18. Horizontal Accelerator

    Data.gov (United States)

    Federal Laboratory Consortium — The Horizontal Accelerator (HA) Facility is a versatile research tool available for use on projects requiring simulation of the crash environment. The HA Facility is...

  19. History of hadron therapy accelerators.

    Science.gov (United States)

    Degiovanni, Alberto; Amaldi, Ugo

    2015-06-01

    In the last 60 years, hadron therapy has made great advances passing from a stage of pure research to a well-established treatment modality for solid tumours. In this paper the history of hadron therapy accelerators is reviewed, starting from the first cyclotrons used in the thirties for neutron therapy and passing to more modern and flexible machines used nowadays. The technical developments have been accompanied by clinical studies that allowed the selection of the tumours which are more sensitive to this type of radiotherapy. This paper aims at giving a review of the origin and the present status of hadron therapy accelerators, describing the technological basis and the continuous development of this application to medicine of instruments developed for fundamental science. At the end the present challenges are reviewed.

  20. Effect of the Metal Part of Siemens PRIMUS Accelerator Treatment Couch on Radiotherapy Dose by MatriXX%应用MatriXX测量西门子PRIMUS加速器治疗床的金属部件对射野剂量分布的影响

    Institute of Scientific and Technical Information of China (English)

    余辉; 张书旭; 陈静

    2011-01-01

    Objective: To research on the effect of the metal part of Siemens PRIMUS accelerator treatment couch on radiotherapy dose.Methods: There are three parts of PIM S accelerator treatment couch.They are couch head, carbon fiber clinoid plate and plexiglass clinoid plate.These three parts all have metal part.In our research, MatriXX was clamped in two IBA phantoms whose thick was 6 cm.The center axis of MatriXX was aligned with the center Y-axis of couch.The distance of source to measure center was 100 cm.Firstly, we confirmed respectively the gantry angle limit where the field 10 cm×l0 cm can light these metal parts of three parts.Three gantry angle limits were respectively 110°~135°(symmetrically 225°~250°), 115°~140°(symmetrically 220°~245°) and 155°~lS0°(symmelrically 180°~205°).Secondary, in above gantry angle limits, each internal 5° we set a measure field whose MU was 50, respectively we measured the effect of these three metal parts on 6 MV X-ray dose.Thirdly, MatriXX was put on the plexiglass clinoid plate.Three were nothing except air before 6 MV X-ray reached MatriXX phantom.We repeated above irradiated condition to measure absorbed dose expect couch.Finally, the attenuated data of three metal parts was got from MatriXX software.Results: In the center axis of measured field, the attenuated data of isocenter were respectively 2.1%~22.4%, 1.3%~43.8% and 0%~46.7%.The max attenuated data were respectively 12.1%~32.2%, 12.9%~65.3% and 32.8%~58.3%.Conclusions: The metal part of PRIMUS accelerator treatment couch may attenuate much radiotherapy dose.They must be got out of field when positioning.%目的:测量西门子PRIMUS加速器治疗床的金属部件对射野剂量分布的影响.方法:PRIMUS加速器治疗床由可拆卸的床头、网状碳纤维床板和有机玻璃床板三部分组成,3种床板均有金属部件.本文将MatriXX夹在上下各6 cm厚的IBA固体水体模的中间,对齐Matri

  1. Future accelerators

    CERN Document Server

    Hübner, K

    1999-01-01

    An overview of the various schemes for electron-positron linear colliders is given and the status of the development of key components and the various test facilities is given. The present studies of muon-muon colliders and very large hadron colliders are summarized including the plans for component development and tests. Accelerator research and development to achieve highest gradients in linear accelerators is outlined. (44 refs).

  2. Adaptive Motion Compensation in Radiotherapy

    CERN Document Server

    Murphy, Martin J

    2011-01-01

    External-beam radiotherapy has long been challenged by the simple fact that patients can (and do) move during the delivery of radiation. Recent advances in imaging and beam delivery technologies have made the solution--adapting delivery to natural movement--a practical reality. Adaptive Motion Compensation in Radiotherapy provides the first detailed treatment of online interventional techniques for motion compensation radiotherapy. This authoritative book discusses: Each of the contributing elements of a motion-adaptive system, including target detection and tracking, beam adaptation, and pati

  3. 基于嵌入式Web的HART仪表远程控制系统%HART Instrument Remote Control System Based on Embedded Web

    Institute of Scientific and Technical Information of China (English)

    吴贞贞; 宁永海

    2014-01-01

    To solve wired HART instruments is easily influenced by poor environments and cost issues in the remote transmission,combining the application of embedded Linux system on the remote industrial control field,a HART instrument remote control system based on embedded Web is proposed. Boa server is transplanted on the embedded system with the S3C2440 processor and network chip DM9000,and the CGI technology is used to achieve dynamic web control. With this control system, HART instrument is remote monitoring through Web browser by clients indoors,and a special configu-ration software is not needed.%为解决有线HART仪表在恶劣环境中远程传输时易受影响、成本高等问题,结合嵌入式linux系统在远程工业控制中的应用,提出了一种基于嵌入式Web的HART仪表远程控制系统。采用S3C2440处理器和DM9000网络芯片,在嵌入式系统上移植Boa Web服务器,并运用CGI技术实现动态网页控制。利用该控制系统,客户只需在室内通过浏览器即可对HART仪表进行远程监控,且不需要专门的组态软件。

  4. Electron energy and angular distributions in radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Deasy, J.O.

    1992-01-01

    Electron energy and angular distributions and associated effects for radiotherapy accelerators and beta-ray ophthalmic applicators have been measured and modeled. Ophthalmic applicator extrapolation chamber calibration geometries were studied using Monte Carlo calculations and analytic methods. A large interface effect increases the surface dose by a factor of about 1.5 and makes very small gap width measurements necessary (0.1--0.2 mm). Dose deposition in tissue near the surface was simulated using the Monte Carlo technique. Charge collection in the extrapolation chamber was analytically modeled on the basis of ionized free electrons back-diffusing into the cathode, while taking into account attachment to O[sub 2] ions. Two small, portable, magnetic spectrometers for the measurement of clinical radiotherapy electron beams were constructed. One employs film as a spectrograph and is suitable for routine measurements; the second is a 90[degree] single-focusing spectrometer and uses fast pulse counting electrons and pulse-height analysis. Spectra were measured for the University of Louisville's Theratronics T20 and Philips SL25 linear accelerators. The T20 spectra were all Gaussian with energy widths of about 5%. The SL25 energy spectra were of varied shapes, with energy widths of 10--20%. Evidence of 3--7% shifts in the average energy of the SL25 beams was observed. Angular measurements were made which showed the Gaussian angular spread of the incident beam. The Monte Carlo code CYLTRAN and measured spectra were used to reconstruct depth dose curves. The peak energy structure only marginally affects the shape of the depth-dose curve, and some features of the depth-dose curves must be affected by incident straggled or widely-scattered electrons. In the absence of lower energy straggled electrons, the range parameters and the maximum dose gradient depend on the mean energy of the peak electrons.

  5. Stereotactic radiotherapy (SRT) for acoustic neuroma by linear accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Sakamoto, Tooru; Shirato, Hiroki; Fukuda, Satoshi [Hokkaido Univ., Sapporo (Japan). School of Medicine] [and others

    1997-10-01

    We analyzed forty one patients with acoustic neuroma treated by SRT giving 36 Gy in 20 fractions to 48 Gy in 23 fractions during 1991 and 1997, and found a sterilization of tumor size in 97.6%. Twenty-six patients had measurable hearing before and after SRT and 43.5% of patients showed change in pure tone average less than 10 dB, 82.6% less than 20 dB at the last follow-up examination. Facial and trigeminal nerve function was evaluated in 41 patients. Transient facial weakness developed in 4.8% and trigeminal neuropathy in 9.6% of irradiated cases. We consider that SRT complications are less than that of gamma-knife, although the longer follow-up period should be needed. (author)

  6. HART智能仪表通用组态软件开发%Development of General Configuration Software for HART Intelligent Instruments

    Institute of Scientific and Technical Information of China (English)

    孙明革; 关波; 徐松梅

    2014-01-01

    介绍了支持HART协议仪表的PC机组态软件的开发与应用,该软件采用C#编制,通过驱动采用USB接口连接的HART/USB转换器与多种智能HART仪表进行通讯,采集、修改HART智能仪表的各种信息,实现仪表量程、标号、标注信息及仪表自身校准等操作,并实现智能HART仪表的远程管理与控制.

  7. MedLinac2: a GEANT4 based software package for radiotherapy

    Directory of Open Access Journals (Sweden)

    Barbara Caccia

    2010-06-01

    Full Text Available Dose distribution evaluation in oncological radiotherapy treatments is an outstanding problem that requires sophisticated computing technologies to optimize the clinical results (i.e. increase the dose to the tumour and reduce the dose to the healthy tissues. Nowdays, dose calculation algorithms based on the Monte Carlo method are generally regarded as the most accurate tools for radiotherapy. The flexibility of the GEANT4 (GEometry ANd Tracking Monte Carlo particle transport simulation code allows a wide range of applications, from high-energy to medical physics. In order to disseminate and encourage the use of Monte Carlo method in oncological radiotherapy, a software package based on the GEANT4 Monte Carlo toolkit has been developed. The developed package (MedLinac2 allows to simulate in an adequate flexible way a linear accelerator for radiotherapy and to evaluate the dose distributions.

  8. Postoperative radiotherapy for endometrial cancer

    National Research Council Canada - National Science Library

    Choi, Eun Cheol; Kim, Jin Hee; Kim, Ok Bae; Byun, Sang Jun; Park, Seung Gyu; Kwon, Sang Hoon

    2012-01-01

    .... Sixty four patients with stage I-III endometrial cancer (EC) treated with postoperative radiotherapy alone between January 1989 and December 2008 at the Keimyung University Dongsan Medical Center were chosen for the present study...

  9. Targeted intraoperative radiotherapy in oncology

    CERN Document Server

    Keshtgar, Mohammed; Wenz, Frederik

    2014-01-01

    Targeted intraoperative radiotherapy is a major advance in the management of cancer patients. With an emphasis on practical aspects, this book offers an ideal introduction to this innovative  technology for clinicians.

  10. Stereotactic radiotherapy for vestibular schwannoma

    DEFF Research Database (Denmark)

    Muzevic, Dario; Legcevic, Jelena; Splavski, Bruno;

    2014-01-01

    ; Web of Science; CAB Abstracts; ISRCTN and additional sources for published and unpublished trials. The date of the search was 24 July 2014. SELECTION CRITERIA: Randomised controlled trials (RCTs) exploring the efficacy of stereotactic radiotherapy compared with observation alone, microsurgical...

  11. Magnetic resonance imaging for precise radiotherapy of small laboratory animals

    Energy Technology Data Exchange (ETDEWEB)

    Frenzel, Thorsten [Universitaetsklinikum Hamburg-Eppendorf, Hamburg (Germany). Bereich Strahlentherapie; Universitaetsklinikum Hamburg-Eppendorf, Hamburg (Germany). Inst. fuer Anatomie und Experimentelle Morphologie; Kaul, Michael Gerhard; Ernst, Thomas Michael; Salamon, Johannes [Universitaetsklinikum Hamburg-Eppendorf, Hamburg (Germany). Klinik und Poliklinik fuer Diagnostische und Interventionelle Radiologie; Jaeckel, Maria [Universitaetsklinikum Hamburg-Eppendorf, Hamburg (Germany). Klinik und Poliklinik fuer Strahlentherapie und Radioonkologie; Schumacher, Udo [Universitaetsklinikum Hamburg-Eppendorf, Hamburg (Germany). Inst. fuer Anatomie und Experimentelle Morphologie; Kruell, Andreas [Universitaetsklinikum Hamburg-Eppendorf, Hamburg (Germany). Bereich Strahlentherapie

    2017-05-01

    Radiotherapy of small laboratory animals (SLA) is often not as precisely applied as in humans. Here we describe the use of a dedicated SLA magnetic resonance imaging (MRI) scanner for precise tumor volumetry, radiotherapy treatment planning, and diagnostic imaging in order to make the experiments more accurate. Different human cancer cells were injected at the lower trunk of pfp/rag2 and SCID mice to allow for local tumor growth. Data from cross sectional MRI scans were transferred to a clinical treatment planning system (TPS) for humans. Manual palpation of the tumor size was compared with calculated tumor size of the TPS and with tumor weight at necropsy. As a feasibility study MRI based treatment plans were calculated for a clinical 6 MV linear accelerator using a micro multileaf collimator (μMLC). In addition, diagnostic MRI scans were used to investigate animals which did clinical poorly during the study. MRI is superior in precise tumor volume definition whereas manual palpation underestimates their size. Cross sectional MRI allow for treatment planning so that conformal irradiation of mice with a clinical linear accelerator using a μMLC is in principle feasible. Several internal pathologies were detected during the experiment using the dedicated scanner. MRI is a key technology for precise radiotherapy of SLA. The scanning protocols provided are suited for tumor volumetry, treatment planning, and diagnostic imaging.

  12. Radioprotectors in Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Nair, C.K.K. [Bhabha Atomic Research Centre, Mumbai (India); Parida, D.K.; Nomura, Taisei

    2001-03-01

    This review article focuses on clinically relevant radioprotectors and their mechanisms of radioprotection. Radiotherapy is the most common modality of human cancer therapy. Obtaining optimal results requires a judicious balance between the total dose of radiotherapy delivered and the threshold limit of critical surrounding normal tissues, and the normal tissues need to be protected against radiation injury to obtain better tumor control by using a higher dose. For this reason, radiation-protective agents play an important role in clinical radiotherapy. Radiation-protective agents can be classified into three groups: radioprotectors, adaptogens, and absorbents. The first group generally consists of sulfhydryl compounds and other antioxidants. They include several myelo-, entero-, and cerebro-protectors. Adaptogens act as promotors of radioresistance. They are natural protectors that offer chemical protection against low levels of ionizing radiation. Absorbents protect organs from internal radiation and chemicals. They include drugs that prevent incorporation of radioiodine by the thyroid gland and absorption of radionuclides. This article thoroughly describes the properties, mechanisms of action, and perspectives on clinical application of the following categories of radioprotectors: sulfhydryl compounds (e.g., cysteine, cysteamine, glutathione, AET, WR 2127, and other WR-compounds), antioxidants (e.g., tempace, Hoechst 33342, vitamin A, E, and C, TMG, melatonin), angiotensin-converting enzyme (ACE) inhibitors (e.g., captopril, elanopril, penicillamine, pentoxifylline, L-158, 809), cytoprotective agents (mesna, dexrazoxane, and amifostin), metalloelements (e.g., manganese chloride, cadmium salts, bismuth subnitrate), immunomodulators (gamma-interferon, polysaccharides AM5, AM218, heat-killed lactobacillus cells, broncho-vaxom, trehalose dicorynomycolate, and AS101), lipopolysaccharides and prostaglandins, plant extracts and compounds isolated from plants (curcmin

  13. 对无线HART网络的图表路由算法的研究%Research on graph routing algorithm on wireless HART networks

    Institute of Scientific and Technical Information of China (English)

    孙健波; 孙强; 申巍; 张婷婷

    2011-01-01

    在无线HART网络层协议中图表路由算法被规定为常规的路由方法.协议仅对图表路由算法进行了定义以及规定了其特点,并没有实现明确的仿真以及评估,本文在TinyOS中运用nesC语言对图表路由算法进行仿真,并且在吞吐量、延迟2个方面与AODV协议进行对比评估,通过TinyOS模拟仿真和评估可以看出,图表路由算法在无线HART网络中具有明显优势.%According to the wireless HART network layer protocol, graph routing algorithm was proposed as the normal routing method. The protocol only defined and provided the property of graph routing algorithm, didnft implemented the simulation and evaluation. In this paper, the graph routing algorithm was first simulated by nesC coding language in TinyOS. Then the evaluation was made with AODV from two aspects: throughput, latency. Through TinyOS simulation and evaluation, it was demonstrated that graph routing algorithm had a great advantage in wireless HART networks.

  14. Energy aware graph routing algorithm for WirelessHART%基于全网能量均衡的WirelessHART图路由算法

    Institute of Scientific and Technical Information of China (English)

    ZHANG Sheng; YAN Ao; XIANG Zhong-sheng; ZHANG Guo-yong; MA Tian-ming

    2014-01-01

    In WirelessHART network, how to balance the energy consumption while ensuring its reliability is of great challenge. This paper proposed GRAEB algorithm for WirelessHART. First of all, it established the network topology based on graph and it could provid%如何均衡使用网络节点能量并生成高可靠路由是WirelessHART网络研究的一个难题,为此提出了一种GRAEB(graph routing algorithm based on energy balancing)图路由算法。首先,网络被初始化为连通的图结构,能够提高丰富的冗余路径。网络管理器根据全网节点剩余能量、通信周期、链路分布等因子生成节点鲁棒系数矩阵,节点通过比较邻居的鲁棒系数来选择最优路径。另外,规定了邻居节点数的上限阈值,每次路由更新只保留鲁棒系数最优的邻居。仿真结果表明GRAEB不仅提高了网络

  15. Los sistemas Jurídicos y la teoría del razonamiento judicial: una lectura de H.L. A. Hart

    Directory of Open Access Journals (Sweden)

    Victor Alberto Quinche-Ramírez

    2010-03-01

    Full Text Available Este texto propone una reconstrucción de la noción del sistema jurídico en H.L.A. Hart, a partir de una lectura de los términos lenguaje y uso del lenguaje, que el autor emplea aquí y que lo remiten a una tradición específica angloamericana. Se reconstruyen, de acuerdo con esto, los bloques temáticos en que puede leerse el texto de Hart. Se plantea, además, que una lectura de las condiciones de trasfondo del problema del lenguaje puede dirigir los temas precisos de la discusión a un ámbito previo de legitimación, en el que tienen su origen y en lo que puede plantearse una estrategia de lectura. La tesis radica en que el ámbito previo es el de la decisión acerca de las relaciones entre derecho moral, que llevan como consecuencia la construcción de un modelo de sociedad que se adapta a la teoría. Si esto es cierto, la necesidad de legitimar racionalmente el discurso puede ser leída desde el punto de vista justificatorio y fundamentador de una teoría de la argumentación.

  16. 雅迪HARTING:与中国风电产业共迎美好前景——访雅迪HARTING中国能源市场经理缪拯元先生

    Institute of Scientific and Technical Information of China (English)

    王淑梅

    2009-01-01

    @@ 作为全球连接器生产商及工业网络科技的领导者,成立于1945年的德资雅迪HARTING(以下简称"雅迪HARTING")也携其先进的产品和技术及完善的解决方案现身本届风能展.在接待络绎不绝观众的间隙,雅迪HARTING中国能源市场经理缪拯元先生接受了的专访.

  17. Film dosimetry in conformal radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Danciu, C.; Proimos, B.S. [Patras Univ. (Greece). Dept. of Medical Physics

    1995-12-01

    Dosimetry, through a film sandwiched in a transverse cross-section of a solid phantom, is a method of choice in Conformal Radiotherapy because: (a) the blackness (density) of the film at each point offers a measure of the total dose received at that point, and (b) the film is easily calibrated by exposing a film strip in the same cross-section, through a stationary field. The film must therefore have the following properties: (a) it must be slow, in order not to be overexposed, even at a therapeutic dose of 200 cGy, and (b) the response of the film (density versus dose curve) must be independent of the photon energy spectrum. A few slow films were compared. It was found that the Kodak X-Omat V for therapy verification was the best choice. To investigate whether the film response was independent of the photon energy, response curves for six depths, starting from the depth of maximum dose to the depth of 25 cm, in solid phantom were derived. The vertical beam was perpendicular to the anterior surface of the phantom, which was at the distance of 100 cm from the source and the field was 15x15 cm at that distance. This procedure was repeated for photon beams emitted by a Cobalt-60 unit, two 6 MV and 15 MV Linear Accelerators, as well as a 45 MV Betatron. For each of those four different beams the film response was the same for all six depths. The results, as shown in the diagrams, are very satisfactory. The response curve under a geometry similar to that actually applied, when the film is irradiated in a transverse cross-section of the phantom, was derived. The horizontal beam was almost parallel (angle of 85) to the plane of the film. The same was repeated with the central ray parallel to the film (angle 90) and at a distance of 1.5 cm from the horizontal film. The field size was again 15x15 at the lateral entrance surface of the beam. The response curves remained the same, as when the beam was perpendicular to the films.

  18. Saliva in relation to dental erosion before and after radiotherapy

    DEFF Research Database (Denmark)

    Jensdottir, Thorbjorg; von Buchwald, Christian; Nauntofte, Birgitte

    2013-01-01

    Abstract Objective. Low saliva flow and abnormal saliva composition are common conditions after radiotherapy for oral cavity and pharyngeal cancer. Both conditions increase the susceptibility to dental caries and erosion, which may be further accelerated by changes in food preferences. The aim...... of this study was to determine changes in saliva flow and susceptibility to erosive challenges in pharyngeal cancer patients before and after radiotherapy to the head and neck. Materials and methods: The erosive potential of sucking acidic candies with and without calcium was determined in nine patients (50......-68 years) before and after receiving a radiation dose of 66 Gy to the head and neck area. The erosive potential was evaluated from saliva degree of saturation with respect to hydroxyapatite (HAp) and by dissolution of HAp in candy-stimulated saliva. Results. Sucking acidic candies increased saliva flow...

  19. Accelerated Unification

    OpenAIRE

    Arkani-Hamed, Nima; Cohen, Andrew; Georgi, Howard

    2001-01-01

    We construct four dimensional gauge theories in which the successful supersymmetric unification of gauge couplings is preserved but accelerated by N-fold replication of the MSSM gauge and Higgs structure. This results in a low unification scale of $10^{13/N}$ TeV.

  20. Successful Application of Neutron Bubble Detectors in Neutron Dose Monitoring for Primus-M Election Linear Accelerators

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>Neutrons produced by 10 MeV medical electronic linear accelerators used for radiotherapy treatments may be harmful for medical personnel and patients. These neutrons are generated by the photon-induced

  1. Radiotherapy with linear accelerator in a patient with permanent pacemaker, methodology and results of dose determination in a case in vivo; Radioterapia con Linac en un paciente con marcapasos permanente, metodologia y resultados de determinacion de dosis en un caso in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Diaz A, P.; Dominguez O, X.; Toledo B, V.; Nungaray, H.; Zazueta L, F., E-mail: pdiaz@hospitalsanjavier.co [Hospital San Javier, Pablo Casals No. 640, Col. Prados Providencia, 44670 Guadalajara, Jalisco (Mexico)

    2010-09-15

    This work presents the methodology used by the radiotherapy department of the Hospital San Javier in the patients handling with pacemaker. By means of dosimetry to the implant area of the pacemaker together with electrocardiography measurements during the radiotherapy sessions, the pacemaker performance is evaluated with the objective of detecting any anomaly to the same caused by electromagnetic interference and/or accumulated dose. It is necessary to follow specific protocols in these patients type that guarantee their security during the exposition to ionizing radiation since a definitive consent that allows to calculate the failure probability of pacemaker in this therapeutic condition does not exist. (Author)

  2. Electron Energy and Angular Distributions in Radiotherapy.

    Science.gov (United States)

    Deasy, Joseph Owen

    1992-01-01

    Electron energy and angular distributions and associated effects for radiotherapy accelerators and beta -ray ophthalmic applicators have been measured and modeled. Ophthalmic applicator extrapolation chamber calibration geometries were studied using Monte Carlo calculations and analytic methods. A large interface effect increases the surface dose by a factor of about 1.5 and makes very small gap width measurements necessary (0.1-0.2 mm). Dose deposition in tissue near the surface was simulated using the Monte Carlo technique. Charge collection in the extrapolation chamber was analytically modeled on the basis of ionized free electrons back-diffusing into the cathode, while taking into account attachment to O_2 ions. Previous models underpredict the charge loss, mainly because they assume that all the charge carriers are ions. Two small, portable, magnetic spectrometers for the measurement of clinical radiotherapy electron beams were constructed. One employs film as a spectrograph and is suitable for routine measurements; the second is a 90^circ single-focusing spectrometer and uses fast pulse counting electronics and pulse-height analysis. Tests with monoenergetic electron beams at the National Research Council of Canada's electron linear accelerator showed that the system is free from spectral distortion and verified the spectrometers' energy calibrations. Spectra were measured for the University of Louisville's Theratronics T20 and Philips SL25 linear accelerators. The T20 spectra were all nearly Gaussian in shape with energy widths of about 5%. The SL25 energy spectra were of varied shapes, with energy widths of 10-20%. Evidence of 3-7% shifts in the average energy of the SL25 beams was observed. Angular measurements were made which showed the Gaussian angular spread of the incident beam. The Monte Carlo code CYLTRAN and measured spectra were used to reconstruct depth dose curves. Comparisons with measured depth dose curves show that the peak energy structure

  3. Fast online Monte Carlo-based IMRT planning for the MRI linear accelerator

    NARCIS (Netherlands)

    Bol, G.H.; Hissoiny, S.; Lagendijk, J. J. W.; Raaymakers, B. W.

    2012-01-01

    The MRI accelerator, a combination of a 6 MV linear accelerator with a 1.5 T MRI, facilitates continuous patient anatomy updates regarding translations, rotations and deformations of targets and organs at risk. Accounting for these demands high speed, online intensity-modulated radiotherapy (IMRT) r

  4. Particle Accelerators in China

    Science.gov (United States)

    Zhang, Chuang; Fang, Shouxian

    As the special machines that can accelerate charged particle beams to high energy by using electromagnetic fields, particle accelerators have been widely applied in scientific research and various areas of society. The development of particle accelerators in China started in the early 1950s. After a brief review of the history of accelerators, this article describes in the following sections: particle colliders, heavy-ion accelerators, high-intensity proton accelerators, accelerator-based light sources, pulsed power accelerators, small scale accelerators, accelerators for applications, accelerator technology development and advanced accelerator concepts. The prospects of particle accelerators in China are also presented.

  5. Primjena HART protokola za komunikaciju sa pametnim uređajima u polju / Application of the HART protocol for communication with smart field devices / Прикладные HART протоколы - для связи с интеллектуальными полевыми устройствами

    Directory of Open Access Journals (Sweden)

    Adnan M. Mulaosmanović

    2015-07-01

    Full Text Available Pametni instrumentacijski protokoli su dizajnirani za aplikacije gdje se podaci prikupljaju sa instrumenata, senzora i aktuatora koristeći digitalne komunikacijske metode. HART protokol je tipični predstavnik pametnog instrumentacijskog Fieldbus-a. Više od 40 miliona HART uređaja je instalirano u cijelom svijetu, a HART tehnologija predstavlja nejrašireniji komunikacijski protokol za inteligentne procesne instrumente. Dva komunikacijska kanala podržana su od strane HART uređaja, a to su strujni krug 4-20 mA i HART digitalni komunikacijski kanal. Digitalni komunikacijski kanal simultano šalje informacije preko istih žica i bez ometanja analognog kanala. Ovaj dvosmjerni komunikacijski kanal osigurava real time pristup podacima dostupnim na HART pametnim uređajima. U ovom radu govorit će se o osobinama i primjeni HART protokola. / Smart instrumentation protocols are designed for applications where data is collected from instruments, sensors and actuators by digital communication technology. The HART protocol is a typical smart instrumentation Fieldbus. More than 40 million HART devices are installed worlwide, and the HART technology is the most widely usef field communication protocol for intelligent process instrumentation. Two communication channels supported by HART devices are the current loop 4-20 mA, and the HART digital channel. A digital communication channel simultaneously transmits information along the same wire and without disruption to the analog channel. This bi-directional communication channel provides a real time access to available data on HART smart devices. This paper deals with the properties and the application of the HART protocol. / Умные протоколы инструментов предназначены для приложений, где обрабатываются данные, собранные с помощью приборов, датчиков и сенсоров, использующих

  6. MUON ACCELERATION

    Energy Technology Data Exchange (ETDEWEB)

    BERG,S.J.

    2003-11-18

    One of the major motivations driving recent interest in FFAGs is their use for the cost-effective acceleration of muons. This paper summarizes the progress in this area that was achieved leading up to and at the FFAG workshop at KEK from July 7-12, 2003. Much of the relevant background and references are also given here, to give a context to the progress we have made.

  7. Radiotherapy and skin tumors; Radiotherapie et tumeurs curanees

    Energy Technology Data Exchange (ETDEWEB)

    Calitchi, E.; KIrova, Y.; Le bourgeois, J.P. [Hopital Henri-Mondor, 94 - Creteil (France)

    1998-09-01

    Radiotherapy plays an important role in treatment of skin tumours. For skin carcinomas, external irradiation (kilo-voltage X-rays or electrons according to clinical characteristics) is more valuable than interstitial brachytherapy, which is recommended for tumours of the lip and of the nasal vestibule. In mycosis fungoides, total cutaneous electron beam radiation therapy is efficient for patients with limited superficial plaques. In the classical form of Kaposi`s sarcoma, radiotherapy can achieve local control-whereas it obtains good palliative results in the epidemic form. (author)

  8. Laser acceleration

    Science.gov (United States)

    Tajima, T.; Nakajima, K.; Mourou, G.

    2017-02-01

    The fundamental idea of Laser Wakefield Acceleration (LWFA) is reviewed. An ultrafast intense laser pulse drives coherent wakefield with a relativistic amplitude robustly supported by the plasma. While the large amplitude of wakefields involves collective resonant oscillations of the eigenmode of the entire plasma electrons, the wake phase velocity ˜ c and ultrafastness of the laser pulse introduce the wake stability and rigidity. A large number of worldwide experiments show a rapid progress of this concept realization toward both the high-energy accelerator prospect and broad applications. The strong interest in this has been spurring and stimulating novel laser technologies, including the Chirped Pulse Amplification, the Thin Film Compression, the Coherent Amplification Network, and the Relativistic Mirror Compression. These in turn have created a conglomerate of novel science and technology with LWFA to form a new genre of high field science with many parameters of merit in this field increasing exponentially lately. This science has triggered a number of worldwide research centers and initiatives. Associated physics of ion acceleration, X-ray generation, and astrophysical processes of ultrahigh energy cosmic rays are reviewed. Applications such as X-ray free electron laser, cancer therapy, and radioisotope production etc. are considered. A new avenue of LWFA using nanomaterials is also emerging.

  9. Technological advances in radiotherapy for esophageal cancer

    Institute of Scientific and Technical Information of China (English)

    Milan; Vosmik; Jiri; Petera; Igor; Sirak; Miroslav; Hodek; Petr; Paluska; Jiri; Dolezal; Marcela; Kopacova

    2010-01-01

    Radiotherapy with concurrent chemotherapy and surgery represent the main treatment modalities in esophageal cancer.The goal of modern radiotherapy approaches,based on recent technological advances,is to minimize post-treatment complications by improving the gross tumor volume definition (positron emission tomography-based planning),reducing interfraction motion (image-guided radiotherapy) and intrafraction motion (respiratory-gated radiotherapy),and by better dose delivery to the precisely defined planning ...

  10. Utilizing HART Communication Protocol to Realize the Pressure Measurement for Pipeline Gas%用HART通信协议实现管道煤气压力的测量

    Institute of Scientific and Technical Information of China (English)

    陈劲操

    2002-01-01

    讨论了HART(Highway Addressable Remote Transducer)通信协议.选用智能现场设备,设计了HART调制解调器.利用HART通信协议设计了低价格、高精度的管道煤气压力测量方案.

  11. INEEL Advanced Radiotherapy Research Program Annual Report 2001

    Energy Technology Data Exchange (ETDEWEB)

    Venhuizen, James R.

    2002-04-30

    This report summarizes the major activities and accomplishments of the Idaho National Engineering and Environmental Laboratory (INEEL) Advanced Radiotherapy Research Program for calendar year 2001. Applications of supportive research and development, as well as technology deployment in the fields of chemistry, radiation physics and dosimetry, and neutron source design and demonstration are described. Contributions in the fields of physics and biophysics include development of advanced patient treatment planning software, feasibility studies of accelerator neutron source technology for Neutron Capture Therapy (NCT), and completion of major modifications to the research reactor at Washington State University to produce an epithermal-neutron beam for NCT research applications.

  12. INEEL Advanced Radiotherapy Research Program Annual Report 2001

    Energy Technology Data Exchange (ETDEWEB)

    Venhuizen, James Robert

    2002-04-01

    This report summarizes the major activities and accomplishments of the Idaho National Engineering and Environmental Laboratory (INEEL) Advanced Radiotherapy Research Program for calendar year 2001. Applications of supportive research and development, as well as technology deployment in the fields of chemistry, radiation physics and dosimetry, and neutron source design and demonstration are described. Contributions in the fields of physics and biophysics include development of advanced patient treatment planning software, feasibility studies of accelerator neutron source technology for Neutron Capture Therapy (NCT), and completion of major modifications to the research reactor at Washington State University to produce an epithermal-neutron beam for NCT research applications.

  13. Accelerators and the Accelerator Community

    Energy Technology Data Exchange (ETDEWEB)

    Malamud, Ernest; Sessler, Andrew

    2008-06-01

    In this paper, standing back--looking from afar--and adopting a historical perspective, the field of accelerator science is examined. How it grew, what are the forces that made it what it is, where it is now, and what it is likely to be in the future are the subjects explored. Clearly, a great deal of personal opinion is invoked in this process.

  14. The design of instrument management and diagnostic based on wireless hart communication technology%基于无线HART通信技术的仪表管理与诊断系统的设计

    Institute of Scientific and Technical Information of China (English)

    潘操; 王洪元; 高晋树; 许静; 刘晓宇

    2011-01-01

    工业无线技术是降低工业测控系统成本、提高工业测控系统应用范围的革命性技术.文章针对HART智能仪表的广泛使用现状和工业无线需求两方面的考虑,提出了一种基于无线HART通信技术的仪表管理与诊断系统的设计方案.文章首先基于HART通信技术,提出了系统的体系结构,接着论述了无线HART协议和无线HART的四层次模型,并且详细分析了数据链路层无线HART数据的帧格式.最后给出了该系统的主要功能模块的设计,包括设备访问、记录审查、设备组态和智能调节阀诊断等模块.整个系统通过无线HART通信网络实现了现场HART智能仪表数据的上传和下置.其中数据服务器软件将数据按照无线HART数据帧格式进行解析,并通过力控通用SCADA软件ForceControl 6.1的实时历史数据库进行实时存储;应用服务器提供可视化用户界面,完成对现场智能仪表的组态与监控,方便用户操作.该系统具有可扩展性、可重构性等特点,对实现HART智能仪表管理的信息化具有一定应用价值.%Industrial wireless technology is a revolutionary technology which could reduce the cost and improve the range of applications for industrial measurement and control system. Considering the wild using situation of HART and the requirement of industrial wireless communication, this paper proposes a system design scheme about instrument management and diagnostic based on wireless HART communication technology. The article first discusses the architecture of the system based on wireless HART communication technology. Then discusses the wireless HART protocol and wireless HART hierarchical model, and gives a detailed analysis for the wireless HART data frame format. Finally, discusses the functional design about system, including device access, record review, device configuration and diagnostic features such as intelligent control valve module. The entire system achieves a

  15. accelerating cavity

    CERN Multimedia

    On the inside of the cavity there is a layer of niobium. Operating at 4.2 degrees above absolute zero, the niobium is superconducting and carries an accelerating field of 6 million volts per metre with negligible losses. Each cavity has a surface of 6 m2. The niobium layer is only 1.2 microns thick, ten times thinner than a hair. Such a large area had never been coated to such a high accuracy. A speck of dust could ruin the performance of the whole cavity so the work had to be done in an extremely clean environment.

  16. Impact accelerations

    Science.gov (United States)

    Vongierke, H. E.; Brinkley, J. W.

    1975-01-01

    The degree to which impact acceleration is an important factor in space flight environments depends primarily upon the technology of capsule landing deceleration and the weight permissible for the associated hardware: parachutes or deceleration rockets, inflatable air bags, or other impact attenuation systems. The problem most specific to space medicine is the potential change of impact tolerance due to reduced bone mass and muscle strength caused by prolonged weightlessness and physical inactivity. Impact hazards, tolerance limits, and human impact tolerance related to space missions are described.

  17. Le test d'apprentissage HART : l'effet d'évaluation dynamique sur des personnes avec et sans déficience intellectuelle

    OpenAIRE

    2014-01-01

    Cette étude s'interroge sur l'impact d'un entraînement standardisé du raisonnement analogique lors du test HART, sur des personnes présentant ou non une déficience intellectuelle. Les principales données ont été recueillies par le biais de l'enregistrement des mouvements oculaires des participants, grâce auquel a été possible faire émerger des précisions relatives à la performance et aux principaux comportements de résolution mis en oeuvre par les personnes. L'échantillon de base, sans défici...

  18. Prospective randomized trial of surgery combined with preoperative and postoperative radiotherapy for rectal carcinoma

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Objective To assess the effect of surgery combined with preoperative and postoperative radiotherapy(sandwich treatment)in rectal carcinoma.Methods From October 1990 to January 2002,260 patients with stage Ⅱ(117 patients)and stage Ⅲ(143 patients)rectal carcinoma were randomly divided into three groups:sandwich group(92 patients,group A),postoperative radiotherapy group(98 patients,Group B)and operation group(70 patients,Group C).The preoperative accelerated hyperfractionation(15Gy/6f/3d)was given for sandwic...

  19. Implementation of image-guided radiotherapy (IGRT) within the radiotherapy department of the Orleans regional hospital; Mise en place de la radiotherapie guidee par l'image (IGRT) dans le service de radiotherapie du centre hospitalier regional d'Orleans

    Energy Technology Data Exchange (ETDEWEB)

    Champeaux-Orange, E.; Munier, O.; Bouscayrol, H.; Wachter, T. [CHR d' Orleans, 45 (France)

    2010-10-15

    The authors describe the process followed for the implementation of an image-guided radiation therapy (IGRT) in a radiotherapy department. Two Synergy linear accelerators have been selected to introduce this technique using the low-energy conical tomography and the intensity-induced conformational radiotherapy with arc therapy. This implementation comprised the presentation of the equipment to physicians and operators, education by the manufacturer, the development of procedures of determination of the number of volume acquisition per patient and per site, the choice of displacement vectors. Short communication

  20. 基于HART通信协议的智能阀门定位器设计%Design of the Intelligent Valve Positioner Based on HART Protocol

    Institute of Scientific and Technical Information of China (English)

    吴宁胜

    2015-01-01

    阀门定位器是与气动控制阀配套使用的现场仪表。为了提高定位器的控制性能,以AVR单片机为核心,设计了基于HART通信协议的智能阀门定位器。给出了详细的原理框图和软硬件设计方案,研究了两线制总线供电、低功耗设计、阀位控制算法、HART通信接口等技术问题。该设计实现了阀门定位器的智能化、数字化和网络化,具有广阔的应用前景,对相关产品的研制有重要的指导意义。%Valve positioner is one of the field instruments supporting the use of pneumatic control valves. In order to enhance the control performance of the positioner, the intelligent valve positioner based on HART communication protocol has been designed with AVR single chip computer as the core. Detail schematic block diagram and design scheme of hardware and software are given. Several technical issues including two-wire bus power supply, low power consumption design, valve position control algorithm and HART communication interface, etc. , are researched. The design realizes intellectualization, digitization and networking of the valve positioners;it possesses broad application prospects and important guiding significance for the development of related products.

  1. Sensors, motes, and smart dust : WirelessHART sensors are finding application in gas plants, well rigs and soon may be embraced by entire cities

    Energy Technology Data Exchange (ETDEWEB)

    Chandler, G.

    2009-05-15

    The WirelessHART (Highway Addressable Remote Transducer) is wireless communication system designed to address the needs of the process industry. The sensor system can be used in applications that were previously not practical or possible, such as in drilling rigs and gas plants. The wireless aspect is an important new innovation that delivers key economic benefits. For some temperature measurements in industrial plants, it is not always feasible to run wires all the way up the stack. The wireless solution consists of wireless gateways and field devices that receive and condition data from sensors that measure temperatures, pressures, flow rates, vibration, and other process parameters. The same devices also relay the measurement data to the gateway. Up to 100 devices can be linked wirelessly to a gateway, which passes on the process information to the control system of the plant, drilling rig, or other industrial facility. Multiple networks can be bridged using Wi-Fi. Once deployed, the technology optimizes itself. The system is also useful for determining temperatures and pressures on the mud tanks at drilling rigs and blowout preventers. The system is being used in highly automated and multi-process plants like refineries and upgraders where numerous sensors are needed. Savings on the wireless installations allow a company to afford the installation of more sensors in places they previously could not cost-effectively deploy wired sensors, thereby resulting in improved productivity, safety, and reduced plant downtimes. Talisman Energy's Teepee Creek sour gas plant near Grande Prairie Alberta uses the WirelessHART network to measure temperatures, pressure, differential pressure, tank levels, and valve positions. 4 figs.

  2. Thalassaemic osteoarthropathy treated with radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Davies, A.N. (King' s Coll. Hospital, London (United Kingdom))

    1993-11-01

    Patients with beta thalassaemia may develop a specific osteoarthropathy involving the feet. A number of different treatments for this condition have been tried, including rest, analgesia and hypertransfusion. We report a case of a patient with thalassaemic osteoarthropathy who responded to radiotherapy after failing conventional treatment. (author).

  3. Oral complications of cancer radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Dreizen, S.; Daly, T.E.; Drane, J.B.; Brown, L.R.

    1977-02-01

    Injury to surrounding tissues during radiotherapy for oral cancer can have devastating physical and psychologic consequences for the patient. Oral complications include xerostomia, dental decay, mucositis, taste loss, osteoradionecrosis, infection, and trismus. In many instances, these problems can be eradicated or controlled with appropriate treatment.

  4. Technical and dosimetric description of a hard-docking applicator system for intraoperative radiotherapy with electron beams in a non-dedicated accelerator; Descripcion tecnica y dosimetrica de un sistema aplicador de alineacion rigida para radioterapia intraoperatoria con haces de electrones en acelerador convencional

    Energy Technology Data Exchange (ETDEWEB)

    Sendon del Rio, J. R.; Ayala Lazaro, R.; Jimenez Rojas, R.; Gomez Cores, S.; Gonzalez Ruiz, C.; Garcia Hernandez, M. J.; Lopez Bote, M. A.

    2013-07-01

    Our experience with a hard-docking applicator system for intraoperative electron-beam radiotherapy is described. In the introduction, we review the configuration options of the applicator systems. In the following section, the applicator system us ed and the methods of measurement are described. The dosimetric characterization, some problems related to the system and the solutions we adopted are shown in results. Finally, the dosimetric behavior is discussed developing a consistent theoretical explanation. (Author)

  5. Clinical utility of RapidArcTM radiotherapy technology

    Directory of Open Access Journals (Sweden)

    Infusino E

    2015-11-01

    Full Text Available Erminia Infusino Department of Radiotherapy, Campus Bio-Medico University Hospital, Rome, Italy Abstract: RapidArcTM is a radiation technique that delivers highly conformal dose distributions through the complete rotation (360° and speed variation of the linear accelerator gantry. This technique, called volumetric modulated arc therapy (VMAT, compared with conventional radiotherapy techniques, can achieve high-target volume coverage and sparing damage to normal tissues. RapidArc delivers precise dose distribution and conformity similar to or greater than intensity-modulated radiation therapy in a short time, generally a few minutes, to which image-guided radiation therapy is added. RapidArc has become a currently used technology in many centers, which use RapidArc technology to treat a large number of patients. Large and small hospitals use it to treat the most challenging cases, but more and more frequently for the most common cancers. The clinical use of RapidArc and VMAT technology is constantly growing. At present, a limited number of clinical data are published, mostly concerning planning and feasibility studies. Clinical outcome data are increasing for a few tumor sites, even if only a little. The purpose of this work is to discuss the current status of VMAT techniques in clinical use through a review of the published data of planning systems and clinical outcomes in several tumor sites. The study consisted of a systematic review based on analysis of manuscripts retrieved from the PubMed, BioMed Central, and Scopus databases by searching for the keywords "RapidArc", "Volumetric modulated arc radiotherapy", and "Intensity-modulated radiotherapy". Keywords: IMRT, VMAT, SBRT, SRS, treatment planning software 

  6. Quality management system in radiotherapy in the light of regulations applicable in Poland.

    Science.gov (United States)

    Bogusz-Czerniewicz, Marta

    2012-01-01

    The need to establish conditions for safe irradiation was noted in Poland back in 1986 in the Atomic Law, but for over 16 years no regulations regarding this aspect were passed. The radiological incident in Bialystok (Poland) in 2001 undeniably accelerated the implementation of new legal regulations. Nevertheless, in the absence of national guidelines until 2002, most health care institutions resorted to the quality management system (QMS) model proposed by the ISO norm 9001:2000. Eventually, practice proved the theory and the aforementioned model was also implemented into Polish acts of law defining basic requirements for QMS in radiotherapy. The aim of this work is to review current national regulations regarding QMS in radiotherapy, in particular those referring to standard procedures, the establishment of a commission for procedures and performance of external and internal clinical audits in oncological radiotherapy, as well as to present the process of their implementation into the practice of health care institutions.

  7. Clinical advantages of carbon-ion radiotherapy

    Science.gov (United States)

    Tsujii, Hirohiko; Kamada, Tadashi; Baba, Masayuki; Tsuji, Hiroshi; Kato, Hirotoshi; Kato, Shingo; Yamada, Shigeru; Yasuda, Shigeo; Yanagi, Takeshi; Kato, Hiroyuki; Hara, Ryusuke; Yamamoto, Naotaka; Mizoe, Junetsu

    2008-07-01

    Carbon-ion radiotherapy (C-ion RT) possesses physical and biological advantages. It was started at NIRS in 1994 using the Heavy Ion Medical Accelerator in Chiba (HIMAC); since then more than 50 protocol studies have been conducted on almost 4000 patients with a variety of tumors. Clinical experiences have demonstrated that C-ion RT is effective in such regions as the head and neck, skull base, lung, liver, prostate, bone and soft tissues, and pelvic recurrence of rectal cancer, as well as for histological types including adenocarcinoma, adenoid cystic carcinoma, malignant melanoma and various types of sarcomas, against which photon therapy could be less effective. Furthermore, when compared with photon and proton RT, a significant reduction of overall treatment time and fractions has been accomplished without enhancing toxicities. Currently, the number of irradiation sessions per patient averages 13 fractions spread over approximately three weeks. This means that in a carbon therapy facility a larger number of patients than is possible with other modalities can be treated over the same period of time.

  8. Present Status of Radiotherapy in Clinical Practice

    Science.gov (United States)

    Duehmke, Eckhart

    Aims of radiation oncology are cure from malignant diseases and - at the same time preservation of anatomy (e.g. female breast, uterus, prostate) and organ functions (e.g. brain, eye, voice, sphincter ani). At present, methods and results of clinical radiotherapy (RT) are based on experiences with natural history and radiobiology of malignant tumors in properly defined situations as well as on technical developments since World War II in geometrical and biological treatment planning in teletherapy and brachytherapy. Radiobiological research revealed tolerance limits of healthy tissues to be respected, effective total treatment doses of high cure probability depending on histology and tumor volume, and - more recently - altered fractionation schemes to be adapted to specific growth fractions and intrinsic radiosensitivities of clonogenic tumor cells. In addition, Biological Response Modifiers (BRM), such as cis-platinum, oxygen and hyperthermia may steepen cell survival curves of hypoxic tumor cells, others - such as tetrachiordekaoxid (TCDO) - may enhance repair of normal tissues. Computer assisted techniques in geometrical RT-planning based on individual healthy and pathologic anatomy (CT, MRT) provide high precision RT for well defined brain lesions by using dedicated linear accelerators (Stereotaxy). CT-based individual tissue compensators help with homogenization of distorted dose distributions in magna field irradiation for malignant lymphomas and with total body irradiation (TBI) before allogeneic bone marrow transplantation, e.g. for leukemia. RT with fast neutrons, Boron Neutron Capture Therapy (BNCT), RT with protons and heavy ions need to be tested in randomized trials before implementation into clinical routine.

  9. The evaluation of neutron and gamma ray dose equivalent distributions in patients and the effectiveness of shield materials for high energy photons radiotherapy facilities

    Energy Technology Data Exchange (ETDEWEB)

    Ghassoun, J., E-mail: ghassoun@ucam.ac.ma [EPRA, Department of Physics, Faculty of Sciences Semlalia, PO Box: 2390, 40000 Marrakech (Morocco); Senhou, N. [EPRA, Department of Physics, Faculty of Sciences Semlalia, PO Box: 2390, 40000 Marrakech (Morocco)

    2012-04-15

    In this study, the MCNP5 code was used to model radiotherapy room of a medical linear accelerator operating at 18 MV and to evaluate the neutron and the secondary gamma ray fluences, the energy spectra and the dose equivalent distributions inside a liquid tissue-equivalent (TE) phantom. The obtained results were compared with measured data published in the literature. Moreover, the shielding effects of various neutron material shields on the radiotherapy room wall were also investigated. Our simulation results showed that paraffin wax containing boron carbide presents enough effectiveness to reduce both neutron and secondary gamma ray doses. - Highlights: Black-Right-Pointing-Pointer The Monte Carlo method has been used to model radiotherapy room of a 18 MV linear accelerator. Black-Right-Pointing-Pointer The neutron and the gamma ray dose equivalent distributions inside a liquid (TE) phantom were evaluated. Black-Right-Pointing-Pointer The radiotherapy room shielding performance has been also investigated.

  10. Pediatric radiotherapy planning and treatment

    CERN Document Server

    Olch, Arthur J

    2013-01-01

    "This is a very well-written and -organized book covering the planning and delivery aspects unique to pediatric radiotherapy. The author is a respected and well-known medical physicist with extensive pediatric radiotherapy experience. … a very useful book for any clinical physicist treating pediatric cases and seeking contextual and historical perspective. … a great reference for medical physicists who may not see many pediatric cases and can look to this text as a one-stop shop for not only a comprehensive overview, but detailed explanation for specific pediatric disease sites. Overall, it is a great addition to the reference library of any radiation therapy physicist."-Medical Physics, April 2014.

  11. Proton Radiotherapy for Pediatric Sarcoma

    Energy Technology Data Exchange (ETDEWEB)

    Ladra, Matthew M.; Yock, Torunn I., E-mail: tyock@partners.org [Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA 02114 (United States)

    2014-01-14

    Pediatric sarcomas represent a distinct group of pathologies, with approximately 900 new cases per year in the United States alone. Radiotherapy plays an integral role in the local control of these tumors, which often arise adjacent to critical structures and growing organs. The physical properties of proton beam radiotherapy provide a distinct advantage over standard photon radiation by eliminating excess dose deposited beyond the target volume, thereby reducing both the dose of radiation delivered to non-target structures as well as the total radiation dose delivered to a patient. Dosimetric studies comparing proton plans to IMRT and 3D conformal radiation have demonstrated the superiority of protons in numerous pediatric malignancies and data on long-term clinical outcomes and toxicity is emerging. In this article, we review the existing clinical and dosimetric data regarding the use of proton beam radiation in malignant bone and soft tissue sarcomas.

  12. Gel dosimetry for conformal radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Gambarini, G. [Department of Physics of the University and INFN, Milan (Italy)]. e-mail: grazia.gambarini@mi.infn.it

    2005-07-01

    With the continuum development of conformal radio therapies, aimed at delivering high dose to tumor tissue and low dose to the healthy tissue around, the necessities has appeared of suitable improvement of dosimetry techniques giving the possibility of obtaining dose images to be compared with diagnostic images. Also if wide software has been developed for calculating dose distributions in the fields of various radiotherapy units, experimental verifications are necessary, in particular in the case of complex geometries in conformal radiotherapy. Gel dosimetry is a promising method for imaging the absorbed dose in tissue-equivalent phantoms, with the possibility of 3D reconstruction of the spatial dose distribution, with milli metric resolution. Optical imaging of gel dosimeters, based on visible light absorbance analysis, has shown to be a reliable technique for achieving dose distributions. (Author)

  13. CyberKnife stereotactic radiotherapy as monotherapy for low- to intermediate-stage prostate cancer: Early experience, feasibility, and tolerance

    NARCIS (Netherlands)

    S. Aluwini (Shafak); P.H. van Rooij (Peter); M.S. Hoogeman (Mischa); C.H. Bangma (Chris); W.J. Kirkels (Wim); L. Incrocci (Luca); I.-K.K. Kolkman-Deurloo (Inger-Karina)

    2010-01-01

    textabstractPurpose: The CyberKnife (CK), a linear accelerator mounted on a robotic device, enables excellent dose conformation to the target and minimizes dose to surrounding normal tissue. It is a very suitable device for performing hypofractionated stereotactic body radiotherapy as monotherapy fo

  14. Technological advances in radiotherapy of rectal cancer

    DEFF Research Database (Denmark)

    Appelt, Ane L; Sebag-Montefiore, David

    2016-01-01

    PURPOSE OF REVIEW: This review summarizes the available evidence for the use of modern radiotherapy techniques for chemoradiotherapy for rectal cancer, with specific focus on intensity-modulated radiotherapy (IMRT) and volumetric arc therapy (VMAT) techniques. RECENT FINDINGS: The dosimetric....... Overall results are encouraging, as toxicity levels - although varying across reports - appear lower than for 3D conformal radiotherapy. Innovative treatment techniques and strategies which may be facilitated by the use of IMRT/VMAT include simultaneously integrated tumour boost, adaptive treatment...

  15. Inflammatory Skin Conditions Associated With Radiotherapy.

    Science.gov (United States)

    Hernández Aragüés, I; Pulido Pérez, A; Suárez Fernández, R

    2017-04-01

    Radiotherapy for cancer is used increasingly. Because skin cells undergo rapid turnover, the ionizing radiation of radiotherapy has collateral effects that are often expressed in inflammatory reactions. Some of these reactions-radiodermatitis and recall phenomenon, for example-are very familiar to dermatologists. Other, less common radiotherapy-associated skin conditions are often underdiagnosed but must also be recognized. Copyright © 2016 AEDV. Publicado por Elsevier España, S.L.U. All rights reserved.

  16. Clinical study on radiotherapy combined with surgical treatment of 162 patients with cervical cancer

    Institute of Scientific and Technical Information of China (English)

    Xiaopeng Zhong; Xukun Tong; Lingfang Yang; Donglin Yuan; Huigao Cai

    2008-01-01

    Objective: To compare the 5-year survival rates and complications of internal and external irradiation therapy combined with operation in patients with Ⅱ-Ⅲ period of cervical cancer.Methods: 162 cervical cancer patients after the whole palace resection pelvic lymphadenectomy were divided into three groups, and then accepted radiotherapy.The first group with 91 cases was accepted internal and external irradiation therapy before operation; the second group with 37 cases was given internal irradiation therapy before operation; the third group with 34 cases was given routine postoperative radiotherapy.External irradiation used 60Co irradiation or a linear accelerator, to the whole basin, and the irradiation dose of "B" point in preoperative radiotherapy was 26-30 Gy, in postoperative radiotherapy was 46-50 Gy; intraluminal brachytherapy used 192lr,the dose of "A" point was 5-15 Gy.Results: The 5-year survival rate of preoperative combined radiotherapy group was 78.0%(71/91), preoperative intracavitary radiotherapy group 64.9% (24/37), and postoperative radiotherapy group 35.3% (12/34).Comparing the 5-year survival rates of the preoperative combined and postoperative irradiation groups, there was significant difference (P<0.05).The major complications were radioactive proctitis and cystitis, the complication incidences of three groups were 35.2% (32/91), 32.4% (12/37), 38.2% (13/34), respectively, and the differences were not statistically significant (P>0.05).Conclusion: The intraluminal brachytherapy plus external irradiation can significantly increase the 5-year survival rate of patients with Ⅱa-Ⅲa stages, and the incidence of complications was not significant difference.

  17. Risk-adapted targeted intraoperative radiotherapy versus whole-breast radiotherapy for breast cancer

    DEFF Research Database (Denmark)

    Vaidya, Jayant S; Wenz, Frederik; Bulsara, Max;

    2014-01-01

    The TARGIT-A trial compared risk-adapted radiotherapy using single-dose targeted intraoperative radiotherapy (TARGIT) versus fractionated external beam radiotherapy (EBRT) for breast cancer. We report 5-year results for local recurrence and the first analysis of overall survival....

  18. Radiotherapy dosimetry audit: three decades of improving standards and accuracy in UK clinical practice and trials.

    Science.gov (United States)

    Clark, Catharine H; Aird, Edwin G A; Bolton, Steve; Miles, Elizabeth A; Nisbet, Andrew; Snaith, Julia A D; Thomas, Russell A S; Venables, Karen; Thwaites, David I

    2015-01-01

    Dosimetry audit plays an important role in the development and safety of radiotherapy. National and large scale audits are able to set, maintain and improve standards, as well as having the potential to identify issues which may cause harm to patients. They can support implementation of complex techniques and can facilitate awareness and understanding of any issues which may exist by benchmarking centres with similar equipment. This review examines the development of dosimetry audit in the UK over the past 30 years, including the involvement of the UK in international audits. A summary of audit results is given, with an overview of methodologies employed and lessons learnt. Recent and forthcoming more complex audits are considered, with a focus on future needs including the arrival of proton therapy in the UK and other advanced techniques such as four-dimensional radiotherapy delivery and verification, stereotactic radiotherapy and MR linear accelerators. The work of the main quality assurance and auditing bodies is discussed, including how they are working together to streamline audit and to ensure that all radiotherapy centres are involved. Undertaking regular external audit motivates centres to modernize and develop techniques and provides assurance, not only that radiotherapy is planned and delivered accurately but also that the patient dose delivered is as prescribed.

  19. Uniformity of Dose Distribution in Target Volume in Radiotherapy Techniques for Breast after Mastectomy.

    Directory of Open Access Journals (Sweden)

    Sajad Pashton shayesteh

    2014-03-01

    Full Text Available Background & Objective: Radiotherapy has a very special significance in the treatment of cancer. Beam radiation therapy using photons and electrons produced by a linear accelerator is used extensively in the treatment of breast Cancer. In this article, In addition to providing a description of three techniques of radiotherapy in the treatment of breast cancer, has been Evaluating the effectiveness of this method in the base of uniformity of the dose distribution in the target volume in breast cancer as an important factor in the effectiveness of treatment by radiation.Materials & Methods: Photon, electron and arc Techniques in radiotherapy have been implemented practically using phantom trunk and EDRII films. At the time of practical Techniques, films were placed between the slice of the phantom and were irradiated under selected conditions and the data of these images are analyzed by MATLAB software.Results: Studies show that as a result of using adjacent fields in whole radiotherapy techniques, Parts of the target volume received dose twice or more than the prescribed dose. Meanwhile, by the photon dose technique, rate of receiving dose is more uniform and closer to the prescribed dose.Conclusion: According to scientific studies done by different protocols in breast radiotherapy, tangential photon technique has very less overlap of the field by comparison to other methods and more uniform dose distribution than the prescribed dose .In The base of this research results can be announced the photon techniques in breast cancer treatment was preferred over other methods.

  20. Role of radiotherapy in hospice care

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, Tetsuo; Sugiyama, Akira; Shimizu, Teppei; Ichinohe, Kenji; Teshima, Takeshi; Kaneko, Masao; Hara, Yoshio; Chihara, Satoshi.

    1989-01-01

    The aim of palliative radiotherapy for the terminally ill is to improve the quality of the remaining span of life. From November 1982 to September 1987, 69 patients in the Seirei Hospice have been treated with such radiotherapy, and symptomatic relief was obtained in 64% of these patients. Radiotherapy also proved useful in achieving an improvement in their performance status. While the aim of hospice care is not directed towards treatment of the underlying disease, the use of radiotherapy is considered to have an important role in hospice care.

  1. Radiotherapy of Langerhans' cell histiocytosis. Results and Implications of a national patterns-of-care study

    Energy Technology Data Exchange (ETDEWEB)

    Seegenschmiedt, M.H. [Alfried Krupp Krankenhaus, Essen (Germany). Dept. of Radiation Oncology and Radiotherapy; Olschewski, T.

    2006-11-15

    Purpose: This patterns-of-care study was performed to define the current clinical experience with radiotherapy of Langerhans' cell histiocytosis in adults in Germany and to define open questions resulting from this study. Material and Methods: A standardized questionnaire was sent to 198 German radiotherapy institutions. Data about patient characteristics, stage of disease, practice and fractionation of radiotherapy, outcome of therapy, etc. were systematically evaluated. 123 of 198 institutions answered the complete questionnaire (62.1%). Results: Only 23 of the 123 institutions (18.7%) reported experience with radiotherapy of Langerhans' cell histiocytosis of adults. 18 institutions with 98 patients were evaluable. The majority of patients (72 of 98) was treated on a linear accelerator. The median single dose of radiotherapy was 2 Gy, while the median total dose was 24 Gy. 81 of 89 evaluable patients (91%) reached a local control of the treated lesion(s), 69 of those had a complete remission. Eight of 89 patients (9%) developed an in-field recurrence. 87.8% of patients experienced no acute and 97% of patients no late side effects of radiotherapy. Conclusion: Clinical experience with radiotherapy of Langerhans' cell histiocytosis in adults in Germany is still very limited. Nevertheless, the clinical results - with high remission and local control rates - confirm the effectiveness of radiotherapy in the multidisciplinary treatment of this disease. Due to the small number of patients in this study despite higher incidence rates, the knowledge of this disease has to be multiplied in Germany. Future patients should be systematically included into a prospective radiotherapy registry. (orig.)

  2. Shortest-path routing algorithm based on selected RSL in WlrelessHART%基于RSL筛选的WirelessHART最短路径路由算法

    Institute of Scientific and Technical Information of China (English)

    党魁; 沈继忠; 董利达

    2012-01-01

    无线HART网络协议中提出的Graph路由是同类无线网络中健壮性最好的路由方式之一.针对目前实现该路由方式的算法非常少且性能不佳的现状,提出一种基于BFS的Graph路由算法.该算法得到的路由具有跳间冗余的特点,能够最大限度地增加路由健壮性,并且路径最短;引入RSL作为链路质量衡量标准,剔除质量较差的链路,同时对每跳的邻居数设置上限,保证了路由的健壮性,同时避免了低质量的链路带来的通信资源浪费.此外,论证了协议所没有提及的广播路由存在的必要,并给出了实现算法.%The Graph routing proposed by WirelessHART is one of the routing protocols which with best robustness among all the wireless networks. Since there is little algorithm on Graph routing at present and the routing performance is poor, a shortest-path Graph routing algorithm based on BFS( Breadth-First Search) is presented. The routing algorithm has a character of neighbor redundancies, which can maximize to increase the routing robustness. With the introduction of RSL(Receive Signal Level) as a link quality measurement, removing the links with poor quality, setting an upper limit to the number of neighbors in each hop, both methods are aimed to increase the routing robustness and minimize the waste communication resources. In addition, the necessary of broadcast routing which WirelessHART has not mentioned is demonstrated and the reality algorithm is also proposed.

  3. Associative and Propositional Processes in Evaluation: Conceptual, Empirical, and Metatheoretical Issues--Reply to Albarracin, Hart, and McCulloch (2006), Kruglanski and Dechesne (2006), and Petty and Brinol (2006)

    Science.gov (United States)

    Gawronski, Bertram; Bodenhausen, Galen V.

    2006-01-01

    Replies to commentaries by D. Albarracin, W. Hart, and K. C. McCulloch (see record 2006-10465-004), A. W. Kruglanski and M. Dechesne (see record 2006-10465-005), and R. E. Petty and P. Brinol (see record 2006-10465-006) on B. Gawronski and G. V. Bodenhausen's (2006; see record 2006-10465-003) recently proposed associative-propositional evaluation…

  4. Conformal three dimensional radiotherapy treatment planning in Lund

    Energy Technology Data Exchange (ETDEWEB)

    Knoos, T.; Nilsson, P. [Lund Univ. (Sweden). Dept. of Radiation Physics; Anders, A. [Lund Univ. (Sweden). Dept. of Oncology

    1995-12-01

    The use of conformal therapy is based on 3-dimensional treatment planning as well as on methods and routines for 3-dimensional patient mapping, 3-dimensional virtual simulation and others. The management of patients at the Radiotherapy Department at the University Hospital in Lund (Sweden) is discussed. About 2100 new patients are annually treated with external radiotherapy using seven linear accelerators. Three of the accelerators have dual photon energies and electron treatment facilities. A multi-leaf collimator as well as an electronic portal imaging device are available on one machine. Two simulators and an in-house CT-scanner are used for treatment planning. From 1988 to 1992 Scandiplan (Umplan) was used. Since 1992, the treatment planning system is TMS (HELAX AB, Sweden), which is based on the pencil beam algorithm of Ahnesjo. The calculations use patient modulated accelerator specific energy fluence spectra which are compiled with pencil beams from Monte Carlo generated energy absorption kernels. Heterogeneity corrections are performed with results close to conventional algorithms. Irregular fields, either from standard or individual blocks and from multi-leaf collimators are handled by the treatment planning system. The field shape is determined conveniently using the beam`s eye view. The final field shape is exported electronically to either the block cutting machine or the multileaf collimator control computer. All patient fields are checked against the beam`s eye view during simulation using manual methods. Treatment verification is performed by portal films and in vivo dosimetry with silicon diodes or TL-dosimetry. Up to now, approximately 4400 patients have received a highly individualized 3-dimensional conformal treatment.

  5. Radiotherapy and local control in rectal cancer.

    Science.gov (United States)

    Valentini, V; Rosetto, M E; Fares, C; Mantini, G; Salvi, G; Turriziani, A

    1998-01-01

    Recurrence is a stage in the natural history of rectal cancer. Preoperative radiotherapy or postoperative radiochemotherapy lower the rate of recurrence, improving local control. From 1980 to 1997, at the "Divisione di Radioterapia" of the "Università Cattolica del S. Cuore" of Rome 380 patients with rectal cancer of early clinical stage T2-3, candidates for surgery for cure, underwent radiation therapy. 119 patients underwent postoperative radiotherapy (45-50 Gy); 45 patients underwent "sandwich" radiotherapy (45 Gy:27 Gy before and 28 Gy after surgery), of whom 7 were treated with preoperative radiotherapy alone; 145 patients underwent preoperative concomitant radiochemotherapy according to 3 different protocols, radiotherapy (38 Gy) combined with mitomycin C and 5-FU; radiotherapy (50.4 Gy) combined with cisplatin and 5-FU; radiotherapy (45 Gy) combined with 5-FU and folinic acid. 71 patients were treated with preoperative radiotherapy (38 Gy) combined with IORT (10 Gy). Median follow-up was 6 years. Overall local control was 85% at 3 years, 83% at 5 years, 81% at 10 years. The rate of local control at 5 years was: 76% for postoperative radiotherapy, 83% for "sandwich" radiotherapy, 84% for preoperative radiochemotherapy and 93% for preoperative radiotherapy combined with IORT. Local control was shown to be significantly better with preoperative treatment as compared to postoperative treatment (p = 0.02). The incidence of metastases was 35% in the patients with local recurrence and 16% in those with local control. The difference in survival was highly significant in patients with local control as compared to those with local recurrence: at 5 years 87% and 32% respectively. Patients with local control showed a lower incidence of metastasis and a better survival.

  6. Linac Twins with Flatness Filter Free Option in a Radiotherapy Department

    OpenAIRE

    Treutwein, Marius; Härtl, Petra; Gröger, Christian; Katsilieri, Zaira; Dobler, Barbara

    2014-01-01

    Introduction Having two (or more) equal treatment machines (linac twins) enables a radiotherapy department to facilitate the workflow. The major part of the German standards (DIN) regarding quality assurance of medical linear accelerators has been reworked or has been published for the first time in the recent years due to technical developments. The aim of this study is to setup a commissioning procedure and a quality assurance program for linac twins with flattening filter free option a...

  7. Proton radiotherapy facility for ocular tumors at the IFJ PAN in Krakow Poland

    Energy Technology Data Exchange (ETDEWEB)

    Michalec, Barbara [Henryk Niewodniczanski Institute of Nuclear Physics Polish Academy of Sciences, ul. Radzikowskiego 152, 31-342 Krakow (Poland); Swakon, Jan [Henryk Niewodniczanski Institute of Nuclear Physics Polish Academy of Sciences, ul. Radzikowskiego 152, 31-342 Krakow (Poland)], E-mail: Jan.Swakon@ifj.edu.pl; Sowa, Urszula; Ptaszkiewicz, Marta; Cywicka-Jakiel, Teresa; Olko, PaweL [Henryk Niewodniczanski Institute of Nuclear Physics Polish Academy of Sciences, ul. Radzikowskiego 152, 31-342 Krakow (Poland)

    2010-04-15

    The proton radiotherapy facility for the eye melanoma treatment is under development at the Henryk Niewodniczanski Institute of Nuclear Physics Polish Academy of Sciences (IFJ PAN) in Krakow. The facility uses protons, accelerated by the AIC-144 isochronous cyclotron up to the energy of 60 MeV. The infrastructure and all necessary equipment have been already installed. The paper describes the present status of the facility, gives results of the preliminary beam measurements and shows future perspectives.

  8. Hart' s Interpretation Methodology and its Limits --On Book Review:H. LA Hart%哈特的诠释学方法及其限度——阅读《大师学述:哈特》

    Institute of Scientific and Technical Information of China (English)

    张超

    2011-01-01

    Hart methodologically accomplishes the turn of interpretation in legal philosophy. He holds on the one hand to introduce the internal facet of practice into the analysis of legal theory, and not definitely include moral reason into its reflective attitude on the other. In Hart, McCormick defends Hart through the concept of reflective attitude in interpretation methodology, and with some flaws and shortcomings it needs a further advancement however.%哈特在方法上完成了法哲学发展的诠释学转向。哈特所主张的诠释性方法一方面把实践的内在面相引入法律理论的分析中,另一方面内在面向中的批判反思态度并不必然包括道德理由。在《大师学述:哈特》中,麦考密克围绕着诠释方法通过发展批判反思态度这一概念对哈特的理论进行了辩护。但这个辩护和分析却有其缺陷和不足,因此尚有进一步向前推进的必要。

  9. Treatment outcome in patients with vulvar cancer: comparison of concurrent radiotherapy to postoperative radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ja Young; Kim, Sung Hwan; Kim, Ki Won; Park, Dong Choon; Yoon, Joo Hee; Yoon, Sei Chul [St. Vincent' s Hospital, The Catholic University of Korea School of Medicine, Seoul (Korea, Republic of); Yu, Mina [St. Mary' s Hospital, The Catholic University of Korea School of Medicine, Seoul (Korea, Republic of)

    2012-03-15

    To evaluate outcome and morbidity in patients with vulvar cancer treated with radiotherapy, concurrent chemoradiotherapy or postoperative radiotherapy. The records of 24 patients treated with radiotherapy for vulvar cancer between July 1993 and September 2009 were retrospectively reviewed. All patients received once daily 1.8-4 Gy fractions external beam radiotherapy to median 51.2 Gy (range, 19.8 to 81.6 Gy) on pelvis and inguinal nodes. Seven patients were treated with primary concurrent chemoradiotherapy, one patient was treated with primary radiotherapy alone, four patients received palliative radiotherapy, and twelve patients were treated with postoperative radiotherapy. Twenty patients were eligible for response evaluation. Response rate was 55% (11/20). The 5-year disease free survival was 42.2% and 5-year overall survival was 46.2%, respectively. Fifty percent (12/24) experienced with acute skin complications of grade III or more during radiotherapy. Late complications were found in 8 patients. 50% (6/12) of patients treated with lymph node dissection experienced severe late complications. One patient died of sepsis from lymphedema. However, only 16.6% (2/12) of patients treated with primary radiotherapy developed late complications. Outcome of patients with vulvar cancer treated with radiotherapy showed relatively good local control and low recurrence. Severe late toxicities remained higher in patients treated with both node dissection and radiotherapy.

  10. Radiotherapy and Brachytherapy : Proceedings of the NATO Advanced Study Institute on Physics of Modern Radiotherapy & Brachytherapy

    CERN Document Server

    Lemoigne, Yves

    2009-01-01

    This volume collects a series of lectures presented at the tenth ESI School held at Archamps (FR) in November 2007 and dedicated to radiotherapy and brachytherapy. The lectures focus on the multiple facets of radiotherapy in general, including external radiotherapy (often called teletherapy) as well as internal radiotherapy (called brachytherapy). Radiotherapy strategy and dose management as well as the decisive role of digital imaging in the associated clinical practice are developed in several articles. Grouped under the discipline of Conformal Radiotherapy (CRT), numerous modern techniques, from Multi-Leaf Collimators (MLC) to Intensity Modulated RadioTherapy (IMRT), are explained in detail. The importance of treatment planning based upon patient data from digital imaging (Computed Tomography) is also underlined. Finally, despite the quasi- totality of patients being presently treated with gamma and X-rays, novel powerful tools are emerging using proton and light ions (like carbon ions) beams, bound to bec...

  11. HART智能仪表在线管理系统的应用%The Applications of HART Smart Meter Management System

    Institute of Scientific and Technical Information of China (English)

    夏长松

    2014-01-01

    This paper describes the application of HART Smart Meter management system in Daqing Refining & Chemical Company 300,000 tons / year PPII plant. My unit utilizes the system in the construction stages of commissioning and routine maintenance. It speeds up the construction progress and implements the advance management of equipment. At the same time,the application of management system improves the quality of the instrumentation equipment maintenance and reduces the production fluctuation caused by instrument equipment failure.%本文介绍了HART智能仪表在线管理系统在大庆炼化公司二期30万吨/年聚丙烯装置的工程应用。通过该系统在装置开工调试阶段和日常维护阶段的使用,加快了施工进度,实现了对设备的预支管理,提高了仪表设备维护质量,减少了因仪表设备故障而引起的生产波动。

  12. Depositional environments of the Hart coal zone (Paleocene), Willow Bunch Coalfield, southern Saskatchewan, Canada from petrographic, palynological, paleobotanical, mineral and trace element studies

    Energy Technology Data Exchange (ETDEWEB)

    Potter, J.; Beaton, A.P.; McDougall, W.J.; Nambudiri, E.M.V.; Vigrass, L.W. (University of Regina, SK (Canada). Energy Research Unit)

    1991-12-01

    Coal petrology, palynology, paleobotany and mineralogy of the Hart coal indicate deposition under wet, warm-temperate to subtropical climatic conditions in low-lying backswamps with fluvial channels and locally ponded areas. The coal is dominated by mixed xylitic/attrital lithotypes and by huminite macerals with secondary inertinite macerals and minor liptinite macerals. Good correlation exists between lithotypes and maceral composition. Local and vertical variations in proportions of huminites and inertinites reflect frequent fluctuations in water levels, periodic flooding, desiccation and burning of the peat. Swamps were dominated by {ital Glyptostrobus-Taxodium} forest with {ital Betula-Myrica-Alnus} communities and, locally {ital Laevigatosporites}, which are the dominant contributors to the xylite-rich lithotypes. Attrital lithotypes with abundant {ital Pandanus}, {ital Typha} and {ital Azolla} are consistent with wetter areas of a fluvial environment, including ponds and channels. Trace elements Cr, Cu, Mo, Ni, Si, Ti, U, Se, V, W, K and Th, typically associated with syngenetic minerals kaolinite, calcite and quartz, may have a volcanic source. High concentrations of Na, Ba and Ca found in organic complexes are of secondary origin and probably originate in deep source brines rather than marine surface waters. 55 refs., 11 figs., 5 tabs.

  13. The use of low energy, ion induced nuclear reactions for proton radiotherapy applications

    Energy Technology Data Exchange (ETDEWEB)

    Horn, K.M.; Doyle, B. [Sandia National Labs., Albuquerque, NM (United States); Segal, M.N. [Univ. of New Mexico Medical School, Albuquerque, NM (United States). Dept. of Otolaryngology; Hamm, R.W. [Accsys Technology Inc., Pleasanton, CA (United States); Adler, R.J. [North Star Research Corp., Albuquerque, NM (United States); Glatstein, E. [Univ. of Texas Southwest Medical Center, Dallas, TX (United States)

    1995-04-01

    Medical radiotherapy has traditionally relied upon the use of external photon beams and internally implanted radioisotopes as the chief means of irradiating tumors. However, advances in accelerator technology and the exploitation of novel means of producing radiation may provide useful alternatives to some current modes of medical radiation delivery with reduced total dose to surrounding healthy tissue, reduced expense, or increased treatment accessibility. This paper will briefly overview currently established modes of radiation therapy, techniques still considered experimental but in clinical use, innovative concepts under study that may enable new forms of treatment or enhance existing ones. The potential role of low energy, ion-induced nuclear reactions in radiotherapy applications is examined specifically for the 650 keV d({sup 3}He,p){sup 4}He nuclear reaction. This examination will describe the basic physics associated with this reaction`s production of 17.4 MeV protons and the processes used to fabricate the necessary materials used in the technique. Calculations of the delivered radiation dose, heat generation, and required exposure times are presented. Experimental data are also presented validating the dose calculations. The design of small, lower cost ion accelerators, as embodied in `nested`-tandem and radio frequency quadrupole accelerators is examined, as is the potential use of high-output {sup 3}He and deuterium ion sources. Finally, potential clinical applications are discussed in terms of the advantages and disadvantages of this technique with respect to current radiotherapy methods and equipment.

  14. Reducing radiation induced emesis in abdominal radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Griffin, K. (Royal Marsden Hospital, Sutton (United Kingdom))

    1994-06-01

    In patients with seminoma testes, a comparison was made between radiation induced emesis suffered by patients receiving 'dogleg' radiotherapy with those suffered by patients who received para-aortic radiotherapy. The same comparisons were made between the effects suffered by those patients who received the anti-emetic, Ondansetron, and those suffered by patients who received conventional anti-emetics. (UK).

  15. Radiotherapy versus combined modality in early stages

    DEFF Research Database (Denmark)

    Specht, L.; Carde, P.; Mauch, P.;

    1992-01-01

    In early stage Hodgkin's disease the optimal choice of treatment for the individual patient is still an unresolved issue. So far, twenty-two randomized trials of radiotherapy alone versus radiotherapy plus combination chemotherapy have been carried out worldwide. The preliminary results of a glob...

  16. [Radiotherapy promises: focus on lung cancer].

    Science.gov (United States)

    Jouin, Anaïs; Durand-Labrunie, Jérôme; Leroy, Thomas; Pannier, Diane; Wagner, Antoine; Rault, Erwan; Lartigau, Eric

    2013-06-01

    Radiotherapy is a key cancer treatment, which greatly modified its practice in recent years thanks to medical imaging and technical improvements. The systematic use of computed tomography (CT) for treatment planning, the imaging fusion/co-registration between CT/magnetic resonance imaging (MRI) or CT/positron emission tomography (PET) improve target identification/selection and delineation. New irradiation techniques such as image-guided radiotherapy (IGRT), stereotactic radiotherapy or hadron therapy offer a more diverse therapeutic armamentarium to patients together with lower toxicity. Radiotherapy, as well as medical oncology, tends to offer a personalized treatment to patients thanks to the IGRT, which takes into account the inter- or intra-fraction anatomic variations. IGRT leads to adaptive radiotherapy (ART) with a new planification in the treatment course in order to decrease toxicity and improve tumor control. The use of systemic therapies with radiations needs to be studied in order to improve efficiency without increasing toxicities from these multimodal approaches. Finally, radiotherapy advances were impacted by radiotherapy accidents like Epinal. They led to an increased quality control with the intensification of identity control, the emergence of in vivo dosimetry or the experience feedback committee in radiotherapy. We will illustrate through the example of lung cancer.

  17. Postoperative radiotherapy for endometrial cancer

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Eun Cheol; Kim, Jin Hee; Kim, Ok Bae; Byun, Sang Jun; Park, Seung Gyu; Kwon, Sang Hoon [Dongsan Medical Center, Keimyung University School of Medicine, Daegu (Korea, Republic of)

    2012-09-15

    To investigate the prognostic factors and effectiveness of postoperative radiotherapy alone for endometrial carcinoma. Sixty four patients with stage I?III endometrial cancer (EC) treated with postoperative radiotherapy alone between January 1989 and December 2008 at the Keimyung University Dongsan Medical Center were chosen for the present study. Typically, total hysterectomy, salpingo-oophorectomy and lymphadenectomy were performed on the patient's pelvis. Total dose from 50.4 Gy to 63 Gy was irradiated at pelvis or extended fi eld. Thirteen patients were treated with Co-60 or Ir-192 intracavitary radiotherapy. Follow-up periods were from 7 to 270 months, with a median of 56 months. Five year overall survival (OS) rate was 58.7%, respectively. Five year disease-free survival (DFS) rate was 59.2%, respectively. In univariate analysis for OS and DFS, stage, menopausal age, type of operation, serosal invasion, and lymph node involvement were found to be statistically significant. Histologic type was marginally significant. In multivariate analysis for OS and DFS, stage, types of operation, histologic type were also found to be statistically significant. Treatment failure occurred in 14 patients. The main pattern of failure was found to be distant metastasis. Time to distant metastasis was from 3 to 86 months (median, 12 months). There were no grade 3 or 4 complications. Stage, types of operation, and histologic type could be the predictive prognostic factors in patients. We contemplated postoperative radiation as effective and safe treatment method for EC. Additional treatment would be needed to reduce distant metastasis.

  18. Basic radiotherapy physics and biology

    CERN Document Server

    Chang, David S; Das, Indra J; Mendonca, Marc S; Dynlacht, Joseph R

    2014-01-01

    This book is a concise and well-illustrated review of the physics and biology of radiation therapy intended for radiation oncology residents, radiation therapists, dosimetrists, and physicists. It presents topics that are included on the Radiation Therapy Physics and Biology examinations and is designed with the intent of presenting information in an easily digestible format with maximum retention in mind. The inclusion of mnemonics, rules of thumb, and reader-friendly illustrations throughout the book help to make difficult concepts easier to grasp. Basic Radiotherapy Physics and Biology is a

  19. Quality and safety in radiotherapy

    CERN Document Server

    Pawlicki, Todd

    2010-01-01

    The first text to focus solely on quality and safety in radiotherapy, this work encompasses not only traditional, more technically oriented, quality assurance activities, but also general approaches of quality and safety. It includes contributions from experts both inside and outside the field to present a global view. The task of assuring quality is no longer viewed solely as a technical, equipment-dependent endeavor. Instead, it is now recognized as depending on both the processes and the people delivering the service. Divided into seven broad categories, the text covers: Quality Management

  20. Radiobiology of human cancer radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Andrews, J.R.

    1978-01-01

    The author has systematically collected and collated the scientific literature correlating the basic and clinical sciences in this field in order to produce a definitive treatise. The book thoroughly reviews the biology and biochemistry relevant to radiobiology and describes the critical locus for the extinction of cell reproductive capacity. Extensive coverage is given to oxygen effect, hyperthermia, high linear energy transfer, cell populations, and similar topics. Separate sections cover time, dose, and fractionation; radiation hematology; cancer chemotherapy; and cancer immunology. The book also contains invaluable discussions of techniques for optimizing radiotherapy alone and in combination with other therapies.

  1. Radiotherapy in patients with connective tissue diseases.

    Science.gov (United States)

    Giaj-Levra, Niccolò; Sciascia, Savino; Fiorentino, Alba; Fersino, Sergio; Mazzola, Rosario; Ricchetti, Francesco; Roccatello, Dario; Alongi, Filippo

    2016-03-01

    The decision to offer radiotherapy in patients with connective tissue diseases continues to be challenging. Radiotherapy might trigger the onset of connective tissue diseases by increasing the expression of self-antigens, diminishing regulatory T-cell activity, and activating effectors of innate immunity (dendritic cells) through Toll-like receptor-dependent mechanisms, all of which could potentially lead to breaks of immune tolerance. This potential risk has raised some debate among radiation oncologists about whether patients with connective tissue diseases can tolerate radiation as well as people without connective tissue diseases. Because the number of patients with cancer and connective tissue diseases needing radiotherapy will probably increase due to improvements in medical treatment and longer life expectancy, the issue of interactions between radiotherapy and connective tissue diseases needs to be clearer. In this Review, we discuss available data and evidence for patients with connective tissue diseases treated with radiotherapy.

  2. The first patient treatment of electromagnetic-guided real time adaptive radiotherapy using MLC tracking for lung SABR.

    Science.gov (United States)

    Booth, Jeremy T; Caillet, Vincent; Hardcastle, Nicholas; O'Brien, Ricky; Szymura, Kathryn; Crasta, Charlene; Harris, Benjamin; Haddad, Carol; Eade, Thomas; Keall, Paul J

    2016-10-01

    Real time adaptive radiotherapy that enables smaller irradiated volumes may reduce pulmonary toxicity. We report on the first patient treatment of electromagnetic-guided real time adaptive radiotherapy delivered with MLC tracking for lung stereotactic ablative body radiotherapy. A clinical trial was developed to investigate the safety and feasibility of MLC tracking in lung. The first patient was an 80-year old man with a single left lower lobe lung metastasis to be treated with SABR to 48Gy in 4 fractions. In-house software was integrated with a standard linear accelerator to adapt the treatment beam shape and position based on electromagnetic transponders implanted in the lung. MLC tracking plans were compared against standard ITV-based treatment planning. MLC tracking plan delivery was reconstructed in the patient to confirm safe delivery. Real time adaptive radiotherapy delivered with MLC tracking compared to standard ITV-based planning reduced the PTV by 41% (18.7-11cm(3)) and the mean lung dose by 30% (202-140cGy), V20 by 35% (2.6-1.5%) and V5 by 9% (8.9-8%). An emerging technology, MLC tracking, has been translated into the clinic and used to treat lung SABR patients for the first time. This milestone represents an important first step for clinical real-time adaptive radiotherapy that could reduce pulmonary toxicity in lung radiotherapy. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  3. Additional dose assessment from the activation of high-energy linear accelerators used in radiation therapy

    Directory of Open Access Journals (Sweden)

    Ateia Embarka

    2008-01-01

    Full Text Available It is well known that medical linear accelerators generate activation products when operated above certain electron (photon energies. The aim of the present work is to assess the activation behavior of a medium-energy radiotherapy linear accelerator by applying in situ gamma-ray spectrometry and dose measurements, and to estimate the additional dose to radiotherapy staff on the basis of these results. Spectral analysis was performed parallel to dose rate measurements in the isocenter of the linear accelerator, immediately after the termination of irradiation. The following radioisotopes were detected by spectral analysis: 28Al, 62Cu, 56Mn, 64Cu, 187W, and 57Ni. The short-lived isotopes such as 28Al and 62Cu are the most important factors of the clinical routine, while the contribution to the radiation dose of medium-lived isotopes such as 56Mn, 57Ni, 64Cu, and 187W increases during the working day. Measured dose rates at the isocenter ranged from 2.2 µSv/h to 10 µSv/h in various measuring points of interest for the members of the radiotherapy staff. Within the period of 10 minutes, the dose rate decreased to values of 0.8 µSv/h. According to actual workloads in radiotherapy departments, a realistic exposure scenario was set, resulting in a maximal additional annual whole body dose to the radiotherapy staff of about 3.5 mSv.

  4. Norwegian program of quality assurance in radiotherapy (KVIST) - Organisation, benefits and experience feedback;Programme norvegien d'assurance qualite dans la radiotherapie (KVIST) - Organisation, benefices et retour d'experience

    Energy Technology Data Exchange (ETDEWEB)

    Merete Olerud, H. [Oslo Univ., Autorite Norvegienne de Radioprotection, Osteras, Institut de Physique et Biophysique (Norway); Levernes, S. [Oslo Univ., Centre Hospitalier, Autorite Norvegienne de Radioprotection, Osteras - DNR, Montebello (Norway); Hellebust, T.P. [Autorite Norvegienne de Radioprotection, Osteras, Centre Hospitalier, DNR, Montebello (Norway); Heikkela, I.E. [Autorite Norvegienne de Radioprotection, Osteras D.C., Johannessen, Centre Hospitalier Universitaire - Ulleval, Oslo (Norway); Bjerke, H. [Autorite Norvegienne de Radioprotection, Osteras, Rekstad BL, Centre Hospitalier Universitaire - Ulleval, Oslo (Norway); Sundqvist, E. [Programme Radiographie, Faculte de la Sante, Oslo, College Universitaire, Oslo (Norway); Frykholm, G. [Oslo Univ., Centre Hospitalier Universitaire, Autorite Norvegienne de Radioprotection, Osteras, St.Olav, Trondheim (Norway)

    2009-12-15

    In 2000, the Norwegian Radiation Protection Authority (N.R.P.A.) initiated work to develop a national quality assurance programme in radiotherapy. The program was named K.V.I.S.T.: i.e. Norwegian abbreviation of Quality Assurance in Radiotherapy (KValitetSikring STraleterapi). The programme is performed by the multidisciplinary K.V.I.S.T. Group and aims to stimulate collaboration by focussing on clinical, technical and administrative problems that can be addressed and solved on a national level. An important objective is to establish a positive attitude towards quality assurance and better communication between centres and the various professions and professionals involved in radiotherapy, i.e. the oncologists, medical physicists and radiation therapy technologists. Information is also provided to other stake holders such as health authorities, hospital administrators and patients. In 2007 radiotherapy in Norway represent 10 departments and forty accelerators. Since radiotherapy is given high priority in cancer care good quality assurance is required. The member of the K.V.I.S.T.-group are part time at N.R.P.A. and part time in different radiotherapy departments. Professionals with competencies within radiotherapy (R.T.) have permanent positions in a national public entity. The K.V.I.S.T.-group is multidisciplinary. The K.V.I.S.T.-group acts as a coordinating group for all type of national Q.A. projects. The recommendations/guidelines are developed by national consensus. The work is performed by the radiotherapy community it self, thus creating an atmosphere of ownership. (N.C.)

  5. Piezoelectric particle accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Kemp, Mark A.; Jongewaard, Erik N.; Haase, Andrew A.; Franzi, Matthew

    2017-08-29

    A particle accelerator is provided that includes a piezoelectric accelerator element, where the piezoelectric accelerator element includes a hollow cylindrical shape, and an input transducer, where the input transducer is disposed to provide an input signal to the piezoelectric accelerator element, where the input signal induces a mechanical excitation of the piezoelectric accelerator element, where the mechanical excitation is capable of generating a piezoelectric electric field proximal to an axis of the cylindrical shape, where the piezoelectric accelerator is configured to accelerate a charged particle longitudinally along the axis of the cylindrical shape according to the piezoelectric electric field.

  6. Optimization of human cancer radiotherapy

    CERN Document Server

    Swan, George W

    1981-01-01

    The mathematical models in this book are concerned with a variety of approaches to the manner in which the clinical radiologic treatment of human neoplasms can be improved. These improvements comprise ways of delivering radiation to the malignan­ cies so as to create considerable damage to tumor cells while sparing neighboring normal tissues. There is no unique way of dealing with these improvements. Accord­ ingly, in this book a number of different presentations are given. Each presentation has as its goal some aspect of the improvement, or optimization, of radiotherapy. This book is a collection of current ideas concerned with the optimization of human cancer radiotherapy. It is hoped that readers will build on this collection and develop superior approaches for the understanding of the ways to improve therapy. The author owes a special debt of thanks to Kathy Prindle who breezed through the typing of this book with considerable dexterity. TABLE OF CONTENTS Chapter GENERAL INTRODUCTION 1. 1 Introduction 1...

  7. Dosimetric evaluation of Radiotherapy units wit {sup 60}Co; Evaluacion dosimetrica de unidades de radioterapia con {sup 60}Co

    Energy Technology Data Exchange (ETDEWEB)

    Leon, B. Salinas de; Tovar M, V.; Becerril V, A. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2000-07-01

    The SSDL network of the IAEA performs, every year, quality audit tests for radiotherapy services ({sup 60} Co units and linear accelerators), and for national SSDL as well. Because of the SSDL-Mexico results in these tests and due to our enthusiasm and confidence in our work, a parallel test has been done , which is described in this talk as well as the results. Nowadays, a second parallel test goes up, which could confirm our optimism and open the possibility to our country to start a national dosimetric audit of {sup 60} Co radiotherapy units. (Author)

  8. Acceleration without Horizons

    CERN Document Server

    Doria, Alaric

    2015-01-01

    We derive the metric of an accelerating observer moving with non-constant proper acceleration in flat spacetime. With the exception of a limiting case representing a Rindler observer, there are no horizons. In our solution, observers can accelerate to any desired terminal speed $v_{\\infty} < c$. The motion of the accelerating observer is completely determined by the distance of closest approach and terminal velocity or, equivalently, by an acceleration parameter and terminal velocity.

  9. Pushing the limits of hypofractionation for adjuvant whole breast radiotherapy.

    Science.gov (United States)

    Yarnold, John; Haviland, Joanne

    2010-06-01

    Randomised trials report no disadvantages for hypofractionation based on 2.67 Gy fractions of adjuvant whole breast radiotherapy in terms of local tumour control and late adverse effects. Current 15- or 16-fraction schedules may not represent the limits of this approach, and limited data suggest that fewer larger fractions can be delivered safely provided appropriate downward adjustments are made to the total dose. Therapeutic gain will be undermined if breast cancer proves to be, on average, significantly less sensitive to fraction size than the dose-limiting late reacting normal tissues. If so, shortening overall treatment time might wholly or partially offset these limitations, and these uncertainties are addressed in ongoing or planned trials. Meanwhile, the experience of accelerated partial breast irradiation suggests a strong volume effect for late normal tissue damage. Schedules that may be safe when delivered to small partial volumes cannot be assumed to be safe if delivered to larger partial volumes or to the whole breast. Based on current evidence, testing the effectiveness of a 5-fraction schedule of hypofractionated whole breast radiotherapy appears to be a realisable research objective.

  10. Tissue kinetics in mouse tongue mucosa during daily fractionated radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Doerr, W. [Universitaetsklinikum Carl Gustav Carus, Dresden (Germany). Klinik und Poliklinik fuer Strahlentherapie]|[Institut fuer Strahlenbiologie, Oberschleissheim (Germany); Emmendoerfer, H.; Weber-Frisch, M. [Institut fuer Strahlenbiologie, Oberschleissheim (Germany)

    1996-09-01

    The purpose of the present investigation was to quantify cell flux between the distinct layers of the epithelial lining of the ventral surface of mouse tongue during daily fractionated radiotherapy. In tongue epithelium of untreated mice, the minimum residence time of cells in the germinal layer is 2-3 days. Migration through the functional layers requires an additional 2-3 days before labelled cells are observed in the most superficial layer of nucleated cells. A plateau in LI is observed for several days post-labelling in control epithelium, indicating an equilibrium between loss and proliferation of labelled cells. During fractionated radiotherapy, the minimum time from division to occurrence of labelled cells in the stratum lucidum is less than 2 days, and hence significantly shorter than in control epithelium. In contrast to untreated epithelium, no plateau in the germinal layer LI is seen, indicating that frequently both labelled daughters from dividing labelled cells are being lost from this compartment. In conclusion, the present data support a recently described model of radiation-induced accelerated repopulation in squamous epithelia, which postulates that the majority of damaged cells undergoes abortive divisions resulting in two differentiating daughters. (Author).

  11. Accelerating flight: Edge with arbitrary acceleration

    CSIR Research Space (South Africa)

    Gledhill, Irvy MA

    2011-11-01

    Full Text Available ? temporal scales ? Euler ? convection ? Reynolds ? translational viscous ? Ekman ? rotational viscous ? Translational acceleration ? related to g ? Rotational accleration ? Rossby ? Coriolis ? Centrifugal ? Gravitational ? CSIR 2009...

  12. Psychological and physical distress of cancer patients during radiotherapy

    CERN Document Server

    König, A

    2001-01-01

    Purpose: patients undergoing radiotherapy have physical and psychological symptoms related to the underlying disease and the treatment. In order to give the best possible support to the patients, more knowledge about the amount and the changing of distress in the course of radiotherapy is of essentially importance. Methods: The distress was measured in a consecutive sample of cancer patients (n=82) undergoing radiotherapy. Each patient was given the EORTC-QLQ-C30, the HADS and a special questionnaire which ascertain radiotherapy-specific items before starting the radiotherapy, at the onset of radiotherapy, in the third week of radiotherapy and 3 weeks after the end of radiotherapy. Results: within the first week of treatment the psychological distress of the patients is increasing; 98.8 % of the patients are 'moderate distressed', 46 % 'severe distressed'. General physical symptoms seem not to be affected by the radiotherapy, there is no changing. The distress caused by the organization of the radiotherapy is...

  13. [Radiotherapy of age-related macular degeneration. Case reports].

    Science.gov (United States)

    Puchalska-Niedbał, Lidia; Sylwestrzak, Zofia; Jarema, Alina

    2008-01-01

    The radiotherapy is worth to remember in the most progression causes of AMD, when there is no possibility for application the modern methods of the treatment. We present cause of patient with bilateral advanced changes and low visual acuity in course AMD, who had applied rtg therapy and laser fotocoagulation. The right eye was radiated with foton beam energy 10 MeV using linear accelerator. Dosage of 9 Gy was delivered in 3 fractions through 5 days. In right eye we observed increase of visual acuity from 2/50 before treatment to 3/50 after 12 months, and 0.1 after the 48 months of radiation. The visual acuity in the left eye decreased from 0.2 to 2/50 after the 48 months. The improvement of acuity vision after rtg therapy allowed the patient self-dependence life.

  14. Development of heavy-ion radiotherapy technology with HIMAC

    Science.gov (United States)

    Noda, Koji

    2016-09-01

    Since 1994, HIMAC has carried out clinical studies and treatments for more than 9000 cancer patients with carbon-ion beams. During the first decade of the HIMAC study, a single beam-wobbling method, adopted as the HIMAC beam-delivery technique, was improved for treatments of moving tumors and for obtaining more conformal dose distribution. During the second decade, a pencil-beam 3D scanning method has been developed toward an “adaptive cancer treatment” for treatments of both static and moving tumors. A new treatment research facility was constructed with HIMAC in order to verify the developed 3D scanning technology through a clinical study that has been successfully conducted since 2011. As the next stage, a compact heavy-ion rotating gantry with a superconducting technology has been developed for the more accurate and shorter-course treatments. The twenty-year development of the heavy-ion radiotherapy technologies including accelerator technologies with HIMAC is reviewed.

  15. A halo-ring technique for fractionated stereotactic radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Clark, B.G.; Podgorsak, E.B.; Souhami, L.; Caron, J.-L.; Sixel, K.E. (Montreal General Hospital, PQ (Canada)); Olivier, A. (Montreal Neurological Inst., PQ (Canada). Dept. of Neurosurgery)

    1993-06-01

    Stereotactic radiosurgery has become established as an effective treatment modality for certain non-malignant brain diseases such as arteriovenous malformations. This paper describes an extension of the authors' linear accelerator-based radiosurgical technique to fractionated treatment of intracranial disease. The fractionated stereotactic radiotherapy technique expands the use of the modality by sparing normal cells within the treatment volume thus improving the therapeutic ratio. The first treatment is given using a stereotactic frame both for target localization and patient immobilization. The frame is then removed and subsequent treatments use a standard neurosurgical halo-ring for patient immobilization. The halo-ring is left in place on the skull for the duration of the course of treatment. They describe a sensitive and effective technique for checking the rotational beam parameters and collimator alignment which is used immediately prior to treatment to ensure adequate accuracy of dose delivery to the target volume. (author).

  16. Accelerated hypofractionated adjuvant whole breast radiation with simultaneous integrated boost using volumetric modulated arc therapy for early breast cancer: A phase I/II dosimetric and clinical feasibility study from a tertiary cancer care centre of India

    Directory of Open Access Journals (Sweden)

    Dodul Mondal

    2017-03-01

    Mini abstract: Simultaneous integrated boost with accelerated hypofractionated whole breast radiotherapy using Volumetric Modulated Arc Therapy is a novel approach. Patient selection and technical considerations are of paramount importance. The present study describes successful implementation of this approach.

  17. Adjuvant radiotherapy for gallbladder cancer: A dosimetric comparison of conformal radiotherapy and intensity-modulated radiotherapy

    Institute of Scientific and Technical Information of China (English)

    Xiao-Nan Sun; Qi Wang; Ben-Xing Gu; Yan-Hong Zhu; Jian-Bin Hu; Guo-Zhi Shi; Shu Zheng

    2011-01-01

    AIM: To assess the efficacy and toxicity of conformal radiotherapy (CRT) and compare with intensity-modulated radiotherapy (IMRT) in the treatment of gallbladder cancer.METHODS: Between November 2003 and January 2010, 20 patients with gallbladder cancer were treated with CRT with or without chemotherapy after surgical resection. Preliminary survival data were collected and examined using both Kaplan-Meier and actuarial analysis. Demographic and treatment parameters were collected. All patients were planned to receive 46-56 Gy in 1.8 or 2.0 Gy per fraction. CRT planning was compared with IMRT.RESULTS: The most common reported acute toxicities requiring medication (Radiation Therapy Oncology Group, Radiation Therapy Oncology Group Grade2) were nausea (10/20 patients) and diarrhea (3/20).There were no treatment-related deaths. Compared with CRT planning, IMRT significantly reduced the volume of right kidney receiving > 20 Gy and the volume of liver receiving > 30 Gy. IMRT has a negligible impact on the volume of left kidney receiving > 20 Gy. The 95% of prescribed dose for a planning tumor volume using either 3D CRT or IMRT planning were 84.0% ±6.7%, 82.9% ± 6.1%, respectively (P > 0.05).CONCLUSION: IMRT achieves similar excellent target coverage as compared with CRT planning, while reducingthe mean liver dose and volume above threshold dose. IMRT offers better sparing of the right kidney compared with CRT planning, with a significantly lower mean dose and volume above threshold dose.

  18. Verification of respiratory-gated radiotherapy with new real-time tumour-tracking radiotherapy system using cine EPID images and a log file

    Science.gov (United States)

    Shiinoki, Takehiro; Hanazawa, Hideki; Yuasa, Yuki; Fujimoto, Koya; Uehara, Takuya; Shibuya, Keiko

    2017-02-01

    A combined system comprising the TrueBeam linear accelerator and a new real-time tumour-tracking radiotherapy system, SyncTraX, was installed at our institution. The objectives of this study are to develop a method for the verification of respiratory-gated radiotherapy with SyncTraX using cine electronic portal image device (EPID) images and a log file and to verify this treatment in clinical cases. Respiratory-gated radiotherapy was performed using TrueBeam and the SyncTraX system. Cine EPID images and a log file were acquired for a phantom and three patients during the course of the treatment. Digitally reconstructed radiographs (DRRs) were created for each treatment beam using a planning CT set. The cine EPID images, log file, and DRRs were analysed using a developed software. For the phantom case, the accuracy of the proposed method was evaluated to verify the respiratory-gated radiotherapy. For the clinical cases, the intra- and inter-fractional variations of the fiducial marker used as an internal surrogate were calculated to evaluate the gating accuracy and set-up uncertainty in the superior-inferior (SI), anterior-posterior (AP), and left-right (LR) directions. The proposed method achieved high accuracy for the phantom verification. For the clinical cases, the intra- and inter-fractional variations of the fiducial marker were  ⩽3 mm and  ±3 mm in the SI, AP, and LR directions. We proposed a method for the verification of respiratory-gated radiotherapy with SyncTraX using cine EPID images and a log file and showed that this treatment is performed with high accuracy in clinical cases. This work was partly presented at the 58th Annual meeting of American Association of Physicists in Medicine.

  19. Verification of respiratory-gated radiotherapy with new real-time tumour-tracking radiotherapy system using cine EPID images and a log file.

    Science.gov (United States)

    Shiinoki, Takehiro; Hanazawa, Hideki; Yuasa, Yuki; Fujimoto, Koya; Uehara, Takuya; Shibuya, Keiko

    2017-02-21

    A combined system comprising the TrueBeam linear accelerator and a new real-time tumour-tracking radiotherapy system, SyncTraX, was installed at our institution. The objectives of this study are to develop a method for the verification of respiratory-gated radiotherapy with SyncTraX using cine electronic portal image device (EPID) images and a log file and to verify this treatment in clinical cases. Respiratory-gated radiotherapy was performed using TrueBeam and the SyncTraX system. Cine EPID images and a log file were acquired for a phantom and three patients during the course of the treatment. Digitally reconstructed radiographs (DRRs) were created for each treatment beam using a planning CT set. The cine EPID images, log file, and DRRs were analysed using a developed software. For the phantom case, the accuracy of the proposed method was evaluated to verify the respiratory-gated radiotherapy. For the clinical cases, the intra- and inter-fractional variations of the fiducial marker used as an internal surrogate were calculated to evaluate the gating accuracy and set-up uncertainty in the superior-inferior (SI), anterior-posterior (AP), and left-right (LR) directions. The proposed method achieved high accuracy for the phantom verification. For the clinical cases, the intra- and inter-fractional variations of the fiducial marker were  ⩽3 mm and  ±3 mm in the SI, AP, and LR directions. We proposed a method for the verification of respiratory-gated radiotherapy with SyncTraX using cine EPID images and a log file and showed that this treatment is performed with high accuracy in clinical cases.

  20. Predictors for trismus in patients receiving radiotherapy.

    Science.gov (United States)

    van der Geer, S Joyce; Kamstra, Jolanda I; Roodenburg, Jan L N; van Leeuwen, Marianne; Reintsema, Harry; Langendijk, Johannes A; Dijkstra, Pieter U

    2016-11-01

    Trismus, a restricted mouth opening in head and neck cancer patients may be caused by tumor infiltration in masticatory muscles, radiation-induced fibrosis or scarring after surgery. It may impede oral functioning severely. The aims of our study were to determine: (1) the incidence of trismus at various time points; and (2) the patient, tumor, and treatment characteristics that predict the development of trismus after radiotherapy in head and neck cancer patients using a large database (n = 641). Maximal mouth opening was measured prior to and 6, 12, 18, 24, 36, and 48 months after radiotherapy. Patient, tumor, and treatment characteristics were analyzed as potential predictors for trismus using a multivariable logistic regression analysis. At six months after radiotherapy, 28.1% of the patients without trismus prior to radiotherapy developed trismus for the first time. At subsequent time points the incidence declined. Over a total period of 48 months after radiotherapy, the incidence of trismus was 3.6 per 10 person years at risk. Patients who had tumors located in the oral cavity, oropharynx or nasopharynx, and the salivary glands or ear, and who had a longer overall treatment time of radiotherapy, were more likely to develop trismus in the first six months after radiotherapy. Maximal mouth opening was a predictor for developing trismus at all time points. Incidence of trismus is 3.6 per 10 person years at risk. Tumor localization and overall treatment time of radiotherapy are predictors for developing trismus the first six months after radiotherapy. Maximal mouth opening is a significant predictor for developing trismus at all time points. Regular measurements of maximal mouth opening are needed to predict trismus.

  1. [Current status and perspectives of radiotherapy for esophageal cancer].

    Science.gov (United States)

    Wu, S X; Wang, L H

    2016-09-23

    Esophageal cancer is one of the most common cancers in China. More than 80% of esophageal cancer patients are diagnosed at a late stage and are not eligible for surgery. Radiotherapy is one of the most important modalities in esophageal cancer treatment. Here we reviewed the advances in esophageal cancer radiotherapy and radiotherapy-based combined-modality therapy, such as optimization of radiation dose and target volume, application of precise radiotherapy technique and the integration of radiotherapy with chemotherapy and targeted therapy.

  2. Radiotherapy for MTRA/RT; Strahlentherapie fuer MTRA/RT

    Energy Technology Data Exchange (ETDEWEB)

    Luetter, Christiana [Bonn Univ. (Germany). Radiologische Klinik

    2012-07-01

    The radiological practice textbook covers the following issues: tumor diseases, tumor diagnostics, fundamentals of radiotherapy, DIN, irradiation planning, documentation and quality assurance, strategies of tumor therapy, basic physics of radiotherapy and dosimetry, radiation protection - regulations and guidelines, radiobiology, biological radiation effects, special organ toxicity, psychological and medical attendance of patients, special oncology of the most important organ carcinomas, palliative radiotherapy, radiotherapy of benign diseases, other indications of radiotherapy, supportive therapy.

  3. Hyperfractionated accelerated radiochemotherapy (HFA-RCT) with mitomycin C for advanced head and neck cancer

    NARCIS (Netherlands)

    Widder, J; Dobrowsky, W; Schmid, R; Pokrajac, B; Selzer, E; Potter, R

    2004-01-01

    To investigate efficacy and feasibility of hyperfractionated accelerated radiotherapy combined with mitomycin C, patients with locally advanced unresectable squamous cell carcinomas of the head and neck region were administered 64-66 Gy in four weeks and mitomycin C (20 mg/m(2)) on day five. Twenty-

  4. Variabilidad genética de Hartón del Valle mediante RAM Genetic variability of Harton del Valle by RAM

    Directory of Open Access Journals (Sweden)

    Ana M Piedrahíta

    2008-01-01

    Full Text Available El Hartón del Valle (HV hace parte de las siete razas criollas de ganado bovino colombiano y de acuerdo con los criterios de la FAO está considerado como vulnerable. Para estudiar su variabilidad genética fueron muestreados 33 individuos HV y tres animales de la raza Holstein, como control externo. Se extrajo ADN utilizando el método de Salting Out y las muestras fueron analizadas mediante la técnica molecular RAM (Randon amplified microsatellites. Se utilizaron los cebadores CGA, CCA, TG, y CT. El valor promedio de heterocigosidad esperada fue de 0.26 y el F ST fue 0.39 ± 0.03. Con el índice de Dice-Nei Li y agrupando con el método UPGMA se distinguieron dos grupos: uno integrado por dos hatos de conservación y el otro por cuatro fincas que han compartido reproductores.Harton del Valle (HV breed belong to the seven Creole breeds of the Colombian bovine livestock, according to FAO criteria it is considered as vulnerable. To study its genetical variability, 33 HV animals and three and 3 animals of Holstein breed as a external control were sampled. Simples of DNA were isolated using the Salting Out method and RAM (Random amplified microsatellites technique was used. CGA, CCA, TG and CT primers were used. The mean value of expected heterocigozity was 0.26 and F ST fue 0.39 ± 0.03. Using Dice-Nei Li index and UPGMA clustering method, two groups were distinguished: the first one integrated for two conservation herds and other one by tour faros that have been sharing breeding bulls.

  5. ArcFVDSL, a DSEL Combined to HARTS, a Runtime System Layer to Implement Efficient Numerical Methods to Solve Diffusive Problems on New Heterogeneous Hardware Architecture

    Directory of Open Access Journals (Sweden)

    Gratien Jean-Marc

    2017-03-01

    Full Text Available Nowadays, some frameworks like Arcane and Dune offer a number of advanced tools to deal with the complexity related to parallelism, meshes and linear solvers. However, they do not handle the high level complexity related to discretization methods and physical models. Generative programming and Domain Specific Languages (DSL are key technologies allowing to write code with a high level expressive language and take advantage of the efficiency of generated code with low level services. DSL may be embedded in host languages like Python or C++. Such languages, named in that case Domain Specific Embedded Languages (DSEL, are applied for instance in frameworks like Fenics or Feel++ which are dedicated to the domain of Finite Element (FE methods and Galerkin methods. ArcFVDSL is a DSEL developed on top of the Arcane framework, aiming to implement various lowest order methods (Finite-Volume (FV, Mimetic Finite Difference (MFD, Mixed Hybrid Finite Volume (MHFV, etc. for diffusive problems on general meshes. In this paper, we present various implementations of different complex academic problems. We focus on the capability of the language to allow the description and the resolution of these problems with several lowest-order methods. We illustrate the benefits of such technology combined to runtime system tools like Heterogeneous Abstract RunTime System (HARTS and its ability to handle seamlessly new heterogeneous architectures with multi-core processors enhanced by General Purpose computing on Graphics Processing Units (GP-GPU. We present the performance results of each implementation on different kinds of heterogeneous hardware architecture.

  6. Evaluación de micorrizas nativas en plantas de plátano Hartón (Musa AAB Simmonds en fase de vivero

    Directory of Open Access Journals (Sweden)

    José Luis Barrera-Violeth

    2012-12-01

    Full Text Available En el trabajo se evalúo el efecto de la aplicación de tres géneros nativos de micorrizas vesículo arbusculares sobre el crecimiento de plantas de plátano Hartón (Musa AAB Simmonds en etapa de vivero. Las cepas se obtuvieron de la colección del Laboratorio de Fitopatología de la Universidad de Córdoba, las cuales fueron aisladas de cultivos de plátano en los municipios de Lorica, Los Córdobas y San Bernardo del Viento. Se utilizó el diseño experimental completamente al azar, con seis tratamientos (T: Glomus sp. (T1, Acaullospora sp. (T2, Scutellospora sp. (T3, una combinación de los géneros Glomus, Acaullospora y Scutellospora (T4, un tratamiento químico de fosfato diamónico, DAP (T5 y un control absoluto (T6, con diez repeticiones por tratamiento. Los resultados mostraron que con la combinación de géneros de micorrizas (T4 se obtuvo un mayor número de esporas y un porcentaje más alto de infección, seguido de los tratamientos T1, T3 y T2. Además, con esta combinación se encontraron diferencias significativas en diámetro del pseudotallo, relación de área foliar:peso fresco y seco de raíz, en comparación con los demás tratamientos. El área foliar y la longitud de raíz fueron más altos en el tratamiento T5.

  7. Carotid artery stenosis after neck radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Shimamura, Munehisa; Hashimoto, Yoichiro; Kasuya, Junji; Terasaki, Tadashi [Kumamoto City Hospital (Japan); Uchino, Makoto

    2000-02-01

    Carotid artery stenosis sometimes occurs after cervical radiotherapy. We report a 70-year-old woman with a history of radiotherapy for thyroid cancer at the age of 28 years. She had no signs and symptoms except the skin lesion at the irradiation site. Duplex ultrasonography revealed heterogeneous plaques showing 50% stenosis of bilateral common carotid arteries. Those lesions were observed within segment of irradiation, where atheromatous plaque usually seldom occurs. These indicated that the carotid stenosis was induced by radiotherapy. Although the efficacy of antiplatelet therapy for radiation-induced plaque is not clear, the plaques remained unchanged for 4 years in spite of aspirin administration. (author)

  8. Hippocampal-sparing whole-brain radiotherapy using Elekta equipment.

    Science.gov (United States)

    Nevelsky, Alexander; Ieumwananonthachai, Nantakan; Kaidar-Person, Orit; Bar-Deroma, Raquel; Nasrallah, Haitam; Ben-Yosef, Rahamim; Kuten, Abraham

    2013-05-06

    The purpose of this study was to evaluate the feasibility of hippocampal-sparing whole-brain radiotherapy (HS WBRT) using the Elekta Infinity linear accelerator and Monaco treatment planning system (TPS). Ten treatment plans were created for HS-WBRT to a dose of 30 Gy (10 fractions). RTOG 0933 recommendations were applied for treatment planning. Intensity-modulated radiotherapy (IMRT) plans for the Elekta Infinity linear accelerator were created using Monaco 3.1 TPS-based on a nine-field arrangement and step-and-shoot delivery method. Plan evaluation was performed using D2% and D98% for the whole-brain PTV (defined as whole brain excluding hippocampus avoidance region), D100% and maximum dose to the hippocampus, and maximum dose to optic nerves and chiasm. Homogeneity index (HI) defined as (D2%-D98%)/Dmedian was used to quantify dose homogeneity in the PTV. The whole-brain PTV D2% mean value was 37.28 Gy (range 36.95-37.49Gy), and D98% mean value was 25.37 Gy (range 25.40-25.89 Gy). The hippocampus D100% mean value was 8.37 Gy (range 7.48-8.97 Gy) and the hippocampus maximum dose mean value was 14.35 Gy (range 13.48-15.40 Gy). The maximum dose to optic nerves and optic chiasm for all patients did not exceed 37.50 Gy. HI mean value was 0.36 (range 0.34-0.37). Mean number of segments was 105 (range 88-122) and mean number of monitor units was 1724 (range 1622-1914). Gamma evaluation showed that all plans passed 3%, 3 mm criteria with more than 99% of the measured points. These results indicate that Elekta equipment (Elekta Infinity linac and Monaco TPS) can be used for HS WBRT planning according to compliance criteria defined by the RTOG 0933 protocol.

  9. Accelerated partial breast irradiation

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    @@ Whole breast radiotherapy afier tumor lumpectomy is based on the premise that that the breast cancer recurrence rate is reduced through the elimination of residual cancer foci in the remaining tissue immediately adjacent to the lumpectomy site and occult multicentric areas of in situ or infiltrating cancer in remote areas of the breast. The relevance of remote foci to ipsilateral breast failure rates after breast conserving treatment is debatable, because 65%~100% of recurrences develop in the same quadrant as the initial tumor. This has led several investigators to question whether radiotherapy must be administered to the entire breast.

  10. Intensity-modulated radiotherapy for cancers in childhood; Radiotherapie conformationnelle par modulation d'intensite des tumeurs pediatriques

    Energy Technology Data Exchange (ETDEWEB)

    Leseur, J.; Le Prise, E. [Centre Eugene-Marquis, Service de Radiotherapie, 35 - Rennes (France); Leseur, J.; Carrie, C.; Beneyton, V. [Centre Leon-Berard, Service de Radiotherapie, 69 - Lyon (France); Bernier, V. [Centre Alexis-Vautrin, Service de Radiotherapie, 54 - Vandoeuvre-les-Nancy (France); Beneyton, V. [Centre Paul-Strauss, Service de Radiotherapie, 67 - Strasbourg (France); Mahee, M.A.; Supiot, S. [Centre Rene-Gauducheau, Service de Radiotherapie, 44 - Nantes - Saint-Herblain (France)

    2009-10-15

    Approximately 40-50% of children with cancer will be irradiated during their treatment. Intensity-modulated radiotherapy (I.M.R.T.) by linear accelerator or helical tomo-therapy improves dose distribution in target volumes and normal tissue sparing. This technology could be particularly useful for pediatric patients to achieve an optimal dose distribution in complex volumes close to critical structures. The use of I.M.R.T. can increase the volume of tissue receiving low-dose radiation, and consequently carcinogenicity in childhood population with a good overall survival and long period of life expectancy. This review will present the current and potential I.M.R.T. indications for cancers in childhood, and discuss the benefits and problems of this technology aiming to define recommendations in the use of I.M.R.T. and specific doses constraints in Pediatrics. (authors)

  11. Measuring neutron spectra in radiotherapy using the nested neutron spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Maglieri, Robert, E-mail: robert.maglieri@mail.mcgill.ca; Evans, Michael; Seuntjens, Jan; Kildea, John [Medical Physics Unit, McGill University, Montreal, Quebec H4A 3J1 (Canada); Licea, Angel [Canadian Nuclear Safety Commission, Ottawa, Ontario K1P 5S9 (Canada)

    2015-11-15

    Purpose: Out-of-field neutron doses resulting from photonuclear interactions in the head of a linear accelerator pose an iatrogenic risk to patients and an occupational risk to personnel during radiotherapy. To quantify neutron production, in-room measurements have traditionally been carried out using Bonner sphere systems (BSS) with activation foils and TLDs. In this work, a recently developed active detector, the nested neutron spectrometer (NNS), was tested in radiotherapy bunkers. Methods: The NNS is designed for easy handling and is more practical than the traditional BSS. Operated in current-mode, the problem of pulse pileup due to high dose-rates is overcome by measuring current, similar to an ionization chamber. In a bunker housing a Varian Clinac 21EX, the performance of the NNS was evaluated in terms of reproducibility, linearity, and dose-rate effects. Using a custom maximum-likelihood expectation–maximization algorithm, measured neutron spectra at various locations inside the bunker were then compared to Monte Carlo simulations of an identical setup. In terms of dose, neutron ambient dose equivalents were calculated from the measured spectra and compared to bubble detector neutron dose equivalent measurements. Results: The NNS-measured spectra for neutrons at various locations in a treatment room were found to be consistent with expectations for both relative shape and absolute magnitude. Neutron fluence-rate decreased with distance from the source and the shape of the spectrum changed from a dominant fast neutron peak near the Linac head to a dominant thermal neutron peak in the moderating conditions of the maze. Monte Carlo data and NNS-measured spectra agreed within 30% at all locations except in the maze where the deviation was a maximum of 40%. Neutron ambient dose equivalents calculated from the authors’ measured spectra were consistent (one standard deviation) with bubble detector measurements in the treatment room. Conclusions: The NNS may

  12. Radiogenomics and radiotherapy response modeling

    Science.gov (United States)

    El Naqa, Issam; Kerns, Sarah L.; Coates, James; Luo, Yi; Speers, Corey; West, Catharine M. L.; Rosenstein, Barry S.; Ten Haken, Randall K.

    2017-08-01

    Advances in patient-specific information and biotechnology have contributed to a new era of computational medicine. Radiogenomics has emerged as a new field that investigates the role of genetics in treatment response to radiation therapy. Radiation oncology is currently attempting to embrace these recent advances and add to its rich history by maintaining its prominent role as a quantitative leader in oncologic response modeling. Here, we provide an overview of radiogenomics starting with genotyping, data aggregation, and application of different modeling approaches based on modifying traditional radiobiological methods or application of advanced machine learning techniques. We highlight the current status and potential for this new field to reshape the landscape of outcome modeling in radiotherapy and drive future advances in computational oncology.

  13. Tomodensitometry images: integration in radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Dessy, F.; Hoornaert, M.T. [Jolimont Hospital, Haine Saint Paul (France). Cancer and Nuclear Medicine Dept.; Malchair, F. [Biomed Engineering, Boncelles (France)

    1995-12-01

    With a view to utilization of CT scan images in radiotherapy, the effective energy and the linearity of four different scanners (Siemens somatom CR, HiQS, Plus and Picker PQ 2000) and two non standard scanners, simulators with CT option (Webb 1990) (Varian Ximatron and Oldelft Simulx CT) has been measured using the method described by White and Speller in 1980. When the linearity relation in presented using the density or the electron density as the abscissa, a blurred area where two different components of equal density or electron density can have two different Hounsfield`s numbers. Using the linearity relation, the density of Rando`s lung heterogeneity is determined. We calculated a treatment planning (TP) using this value and made a comparison between the TP and the real absorbed dose with was measured using diodes. The comparison between the TP and the relative Absorbed doses showed a difference of up to 4.5%.

  14. Radiotherapy. 2. rev. ed.; Strahlentherapie

    Energy Technology Data Exchange (ETDEWEB)

    Wannenmacher, Michael; Debus, Juergen [Radiologische Klinik, Heidelberg (Germany). Abteilung fuer Radioonkologie und Strahlentherapie; Wenz, Frederik (ed.) [Universitaetsmedizin Mannheim (Germany). Klinik fuer Strahlentherapie und Radioonkologie

    2013-07-01

    The purpose of this medical specialty book, besides presenting the state of the art in clinical radiotherapy and radiooncology, is to explain the basic principles of medical physics and radiobiology. Following a number of chapters on general topics and theory it provides detailed coverage of the individual organ systems, briefly addressing future aspects in the process. The authors relate their view that radiooncology as a medical specialty will continue to be under pressure to change and that it will take continuous innovation to secure its status within the interdisciplinary context around the treatment of cancer patients. The authors of this, the textbook's second edition, have dedicated much space to modern methods and techniques in order to do justice to these developments.

  15. Proton radiotherapy of skin carcinomas

    Energy Technology Data Exchange (ETDEWEB)

    Umebayashi, Y.; Uyeno, K.; Otsuka, F. (Tsukuba Univ. (Japan). School of Medicine); Tsujii, H. (Proton Medical Research Center, Tsukuba (Japan))

    1994-01-01

    At the Proton Medical Research Centre, University of Tsukuba, a pilot study of proton-beam radiotherapy was performed in 12 patients with the following types of carcinoma: Bowen's disease (4), oral verrucous carcinoma (5), and squamous cell carcinoma (3). They received total doses of 51-99.2 Gy in fractions of 2-12.5 Gy. All tumours responded well to the treatment. All four lesions of Bowen's disease, three of the five oral verrucous carcinomas, and the three squamous cell carcinomas completely regressed following irradiation. Two squamous cell carcinomas recurred during the follow-up period. One recurrent squamous cell carcinoma was successfully treated by a salvage surgical operation, and in the other case the patient refused further therapy. In two verrucous carcinomas there was 90% regression of tumour volume. No severe radiation-related complication occurred. (Author).

  16. 2014 CERN Accelerator Schools: Plasma Wake Acceleration

    CERN Multimedia

    2014-01-01

    A specialised school on Plasma Wake Acceleration will be held at CERN, Switzerland from 23-29 November, 2014.   This course will be of interest to staff and students in accelerator laboratories, university departments and companies working in or having an interest in the field of new acceleration techniques. Following introductory lectures on plasma and laser physics, the course will cover the different components of a plasma wake accelerator and plasma beam systems. An overview of the experimental studies, diagnostic tools and state of the art wake acceleration facilities, both present and planned, will complement the theoretical part. Topical seminars and a visit of CERN will complete the programme. Further information can be found at: http://cas.web.cern.ch/cas/PlasmaWake2014/CERN-advert.html http://indico.cern.ch/event/285444/

  17. Comparison between steel and lead shieldings for radiotherapy rooms regarding neutron doses to patients

    Energy Technology Data Exchange (ETDEWEB)

    Silva, M.G.; Rebello, W.F.; Andrade, E.R.; Medeiros, M.P.C.; Mendes, R.M.S.; Braga, K.L.; Gomes, R.G., E-mail: eng.cavaliere@gmail.com, E-mail: ggrprojetos@gmail.com [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil). Secao de Engenharia Nuclear; Silva, A.X., E-mail: ademir@con.ufrj.br [Coordenacao dos Programas de Pos-Graduacao em Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil)

    2015-07-01

    The NCRP Report No. 151, Structural Shielding Design and Evaluation for Megavoltage X- and Gamma-Ray Radiotherapy Facilities, considers, in shielding calculations for radiotherapy rooms, the use of lead and/or steel to be applied on bunker walls. The NCRP Report calculations were performed foreseeing a better protection of people outside the radiotherapy room. However, contribution of lead and steel to patient dose should be taken into account for radioprotection purposes. This work presents calculations performed by MCNPX code in analyzing the Ambient Dose Equivalent due to neutron, H *(10){sub n}, within a radiotherapy room, in the patients area, considering the use of additional shielding of 1 TVL of lead or 1 TVL of steel, positioned at the inner faces of walls and ceiling of a bunker. The head of the linear accelerator Varian 2100/2300 C/D was modeled working at 18MeV, with 5 x 5 cm{sup 2}, 10 x 10 cm{sup 2}, 20 x 20 cm{sup 2}, 30 x 30 cm{sup 2} and 40 x 40 cm{sup 2} openings for jaws and MLC and operating in eight gantry's angles. This study shows that the use of lead generates an average value of H *(10){sub n} at patients area, 8.02% higher than the expected when using steel. Further studies should be performed based on experimental data for comparison with those from MCNPX simulation. (author)

  18. Pancreatic insufficiency secondary to abdominal radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Dookeran, K.A.; Thompson, M.M.; Allum, W.H. (Leicester Royal Infirmary (United Kingdom). Dept. of Surgery)

    1993-02-01

    Delayed post-irradiation steatorrhoea secondary to acute pancreatic insufficiency is rare. The authors describe a case occurring in a patient 23 years following radical abdominal radiotherapy for testicular seminoma. (Author).

  19. Historical aspects of heavy ion radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Raju, M.R.

    1995-03-01

    This paper presents historical developments of heavy-ion radiotherapy including discussion of HILAC and HIMAC and discussion of cooperation between Japan and the United States, along with personal reflections.

  20. Stereotactic body radiotherapy a practical guide

    CERN Document Server

    Gaya, Andrew

    2015-01-01

    Collecting the key information in this burgeoning field into a single volume, this handbook for clinical oncology trainees and consultants covers all of the basic aspects of stereotactic radiotherapy systems and treatment and includes plenty of case studies.

  1. Heavy particle radiotherapy: prospects and pitfalls

    Energy Technology Data Exchange (ETDEWEB)

    Faju, M.R.

    1980-01-01

    The use of heavy particles in radiotherapy of tumor volumes is examined. Particles considered are protons, helium ions, heavy ions, negative pions, and fast neutrons. Advantages and disadvantages are discussed. (ACR)

  2. High Energy Particle Accelerators

    CERN Multimedia

    Audio Productions, Inc, New York

    1960-01-01

    Film about the different particle accelerators in the US. Nuclear research in the US has developed into a broad and well-balanced program.Tour of accelerator installations, accelerator development work now in progress and a number of typical experiments with high energy particles. Brookhaven, Cosmotron. Univ. Calif. Berkeley, Bevatron. Anti-proton experiment. Negative k meson experiment. Bubble chambers. A section on an electron accelerator. Projection of new accelerators. Princeton/Penn. build proton synchrotron. Argonne National Lab. Brookhaven, PS construction. Cambridge Electron Accelerator; Harvard/MIT. SLAC studying a linear accelerator. Other research at Madison, Wisconsin, Fixed Field Alternate Gradient Focusing. (FFAG) Oakridge, Tenn., cyclotron. Two-beam machine. Comments : Interesting overview of high energy particle accelerators installations in the US in these early years. .

  3. Improved plasma accelerator

    Science.gov (United States)

    Cheng, D. Y.

    1971-01-01

    Converging, coaxial accelerator electrode configuration operates in vacuum as plasma gun. Plasma forms by periodic injections of high pressure gas that is ionized by electrical discharges. Deflagration mode of discharge provides acceleration, and converging contours of plasma gun provide focusing.

  4. Accelerator Technology Division

    Science.gov (United States)

    1992-04-01

    In fiscal year (FY) 1991, the Accelerator Technology (AT) division continued fulfilling its mission to pursue accelerator science and technology and to develop new accelerator concepts for application to research, defense, energy, industry, and other areas of national interest. This report discusses the following programs: The Ground Test Accelerator Program; APLE Free-Electron Laser Program; Accelerator Transmutation of Waste; JAERI, OMEGA Project, and Intense Neutron Source for Materials Testing; Advanced Free-Electron Laser Initiative; Superconducting Super Collider; The High-Power Microwave Program; (Phi) Factory Collaboration; Neutral Particle Beam Power System Highlights; Accelerator Physics and Special Projects; Magnetic Optics and Beam Diagnostics; Accelerator Design and Engineering; Radio-Frequency Technology; Free-Electron Laser Technology; Accelerator Controls and Automation; Very High-Power Microwave Sources and Effects; and GTA Installation, Commissioning, and Operations.

  5. Blisters - an unusual effect during radiotherapy.

    Science.gov (United States)

    Höller, U; Schubert, T; Budach, V; Trefzer, U; Beyer, M

    2013-11-01

    The skin reaction to radiation is regularly monitored in order to detect enhanced radiosensitivity of the patient, unexpected interactions (e.g. with drugs) or any inadvertent overdosage. It is important to distinguish secondary disease from radiation reaction to provide adequate treatment and to avoid unnecessary discontinuation of radiotherapy. A case of bullous eruption or blisters during radiotherapy of the breast is presented. Differential diagnoses bullous pemphigoid, pemphigus vulgaris, and bullous impetigo are discussed and treatment described.

  6. Radiotherapy in Dupuytren's contracture

    Energy Technology Data Exchange (ETDEWEB)

    Koehler, A.H. (Bezirkskrankenhaus Cottbus (German Democratic Republic))

    1984-01-01

    In Dupuytren's contracture grade I by Iselin radiotherapy is indicated. With X-ray half-depth therapy and a total dose of 20.0 Gy the disease could be treated successfully in 82 % of the cases in a sense of inhibition of progression, whereas in 18 % radiotherapy failed. Possibly the results can be improved by increase of the radiation dose and/or modified fractionating.

  7. Accelerators, Colliders, and Snakes

    Science.gov (United States)

    Courant, Ernest D.

    2003-12-01

    The author traces his involvement in the evolution of particle accelerators over the past 50 years. He participated in building the first billion-volt accelerator, the Brookhaven Cosmotron, which led to the introduction of the "strong-focusing" method that has in turn led to the very large accelerators and colliders of the present day. The problems of acceleration of spin-polarized protons are also addressed, with discussions of depolarizing resonances and "Siberian snakes" as a technique for mitigating these resonances.

  8. R-Dijkstra Algorithm for Realization of Graph Route Mechanism in WirelessHART Networks%适用于WirelessHART网络中实现图路由机制的R-Dijkstra算法

    Institute of Scientific and Technical Information of China (English)

    李世兴; 王宏; 周桂平

    2015-01-01

    WirelessHART protocol presents graph route mechanism without providing the specific realization algorithm.Aiming at the features of graph route in WirelessHART protocol,integrating Dijkstra algorithm,R-Dijkstra algorithm was suitable for graph route realization.R-Dijkstra algorithm defined WirelessHART network as a connected graph. By means of introducing redundancy parameter and route optimization goal,R-Dijkstra algorithm can select the transmission path.The graph route mechanism and R-Di-jkstra algorithm steps described the algorithm realization process. The application example confirms that R-Dijkstra algorithm can meet the demands of graph routes.%在WirelessHART协议中,提出了图路由的路由机制,但并未给出具体的实现算法。针对WirelessHART协议中图路由的特点,结合Dijkstra算法,设计了一种适用于图路由实现的R-Dijkstra算法。 R-Dijkstra算法把WirelessHART网络定义为一个非负权重的连通图,通过引入冗余度参数和路径优化目标,实现了图路由传输路径选择。描述了图路由机制和算法步骤,给出了算法实现过程。应用实例表明,该算法能够满足图路由的要求。

  9. The CERN Accelerator School

    CERN Multimedia

    2016-01-01

    Introduction to accelerator physics The CERN Accelerator School: Introduction to Accelerator Physics, which should have taken place in Istanbul, Turkey, later this year has now been relocated to Budapest, Hungary.  Further details regarding the new hotel and dates will be made available as soon as possible on a new Indico site at the end of May.

  10. Accelerators and Dinosaurs

    CERN Multimedia

    Turner, Michael Stanley

    2003-01-01

    Using naturally occuring particles on which to research might have made accelerators become extinct. But in fact, results from astrophysics have made accelerator physics even more important. Not only are accelerators used in hospitals but they are also being used to understand nature's inner workings by searching for Higgs bosons, CP violation, neutrino mass and dark matter (2 pages)

  11. Far field acceleration

    Energy Technology Data Exchange (ETDEWEB)

    Fernow, R.C.

    1995-07-01

    Far fields are propagating electromagnetic waves far from their source, boundary surfaces, and free charges. The general principles governing the acceleration of charged particles by far fields are reviewed. A survey of proposed field configurations is given. The two most important schemes, Inverse Cerenkov acceleration and Inverse free electron laser acceleration, are discussed in detail.

  12. Acceleration: It's Elementary

    Science.gov (United States)

    Willis, Mariam

    2012-01-01

    Acceleration is one tool for providing high-ability students the opportunity to learn something new every day. Some people talk about acceleration as taking a student out of step. In actuality, what one is doing is putting a student in step with the right curriculum. Whole-grade acceleration, also called grade-skipping, usually happens between…

  13. Evaluación de tres métodos de detección de mastitis y determinación de los agentes patógenos asociados en ganado hartón del valle y lucerna

    OpenAIRE

    Montilla, Lina María; Durán Castro, Carlos Vicente; Rodas Varela, Ángela Graciela

    2009-01-01

    Teniendo en cuenta la importancia que tiene la mastitis bovina en los sistemas de producción de , así como las cuantiosas pérdidas económicas que ocasiona, se evaluaron tres técnicas diagnósticas para la determinación de la mastitis: California Mastitis Test (CMT), Conductividad Eléctrica (CE) y Conteo de Células Somáticas (CCS), y se determinaron los microorganismos causantes de la enfermedad en el ganado Hartón del Valle y Lucerna, para este análisis se tomaron muestras de leche de aquello...

  14. Asociación del gen bola-drb3.2 con el virus de la leucosis bovina (vlb) en ganado criollo hartón del valle

    OpenAIRE

    Posso Terranova, Andrés Mauricio; Muñoz florez, Jaime Eduardo; Giovambattista, guillermo; Alvarez Franco, Luz Angela

    2014-01-01

    En cien muestras de ganado criollo hartón del Valle (HV) del Banco de ADN del Laboratorio de genética animal de la Universidad Nacional de Colombia sede Palmira se determinó la presencia del VLB siguiendo la metodología PCR anidado descrita por Beier et al. (2001) y se genotipificaron los animales para el gen DRB3.2* utilizando la metodología de PCR-SBT (Sequence Based Typings) descrita por Takeshima et al. (2009). Se encontró el porcentaje de presencia del virus. Para el gen BoLA-DRB3.2* se ...

  15. 在PRM上通过CS3000卡件读取现场HART仪表信息%Collecting Information of Field Hart Device Through CS3000’s Card on PRM

    Institute of Scientific and Technical Information of China (English)

    黄军政; 潘辉; 熊正

    2016-01-01

    本文介绍了工厂资源管理器(plant resource manager)(简称:PRM)在整个企业资产管理中所处的地位、作用,在此基础上给出了在PRM上通过CS3000网络读取现场HART仪表信息的方法。%This paper introduces position and function of plant resource manager(abbreviation:PRM), then presents method by which PRM can read information of HART instrument though cs3000’s network.

  16. H. Beale et al., Cases, Materials and Texts on Contract Law, 2nd ed. (Oxford: Hart Publishing, 2010; and T. K. Graziano, Comparative Contract Law: Cases, Materials and Exercises (Basingstoke: Palgrave MacMillan, 2009

    Directory of Open Access Journals (Sweden)

    Rachael L. Johnstone

    2011-03-01

    Full Text Available view essay of the following books on comparative law: Hugh Beale, Bénédicte Fauvarque-Cosson, Jacobien Rutgers, Denis Tallon and Stefan Vogenauer, Cases, Materials and Text on Contract Law, 2nd ed. (Ius Commune Casebooks for the Common Law of Europe No. 6 (Oxford, United Kingdom: Hart Publishing, 2010 lxxxiv + 1358 pp. paper. 38.95 GBP; and Thomas Kadner Graziano, Comparative Contract Law: Cases, Materials and Exercises (Basingstoke, United Kingdom: Palgrage MacMillan, 2009 xi + 510 pp. paper. 34.99 GBP

  17. Vagal cardiac acceleration : occurence, nature and significance

    NARCIS (Netherlands)

    Roossien, Albert

    1994-01-01

    Het zoogdierhart is een autonoom orgaan: de prikkel die aanleiding is tot contractie, ontstaat in het hart zelf in een klein gebied in de wand van het rechter atrium, de sinusknoop. De frequentie van de elkaar opvolgende contracties en relaxaties van de hartspier, die voor een effectieve pompwerking

  18. Radiotherapy, a therapeutic procedure in constant progression in cancer treatment; Radioterapia, un procedimiento terapeutico en progresion constante en el tratamiento oncologico

    Energy Technology Data Exchange (ETDEWEB)

    Blanco, J. A.; Calin Lorca, A.; Herranz Crespo, R.

    2016-08-01

    Radiation oncology or radiotherapy is an eminently clinical specialty, prevention, pathogenesis, clinical presentation, diagnosis, treatment and prognostic assessment of neoplasms, based on ionizing radiation. Modern technology (advances in diagnostic imaging, evolution of computing, massive improvements and incorporating different systems of tracking and tracing in linear accelerators) allows treatment to be more and more accurate, less harmful to the patient and consequently more effective. (Author)

  19. Modern compact accelerators of cyclotron type for medical applications

    Science.gov (United States)

    Smirnov, V.; Vorozhtsov, S.

    2016-09-01

    Ion beam therapy and hadron therapy are types of external beam radiotherapy. Recently, the vast majority of patients have been treated with protons and carbon ions. Typically, the types of accelerators used for therapy were cyclotrons and synchrocyclotrons. It is intuitively clear that a compact facility fits best to a hospital environment intended for particle therapy and medical diagnostics. Another criterion for selection of accelerators to be mentioned in this article is application of superconducting technology to the magnetic system design of the facility. Compact isochronous cyclotrons, which accelerate protons in the energy range 9-30 MeV, have been widely used for production of radionuclides. Energy of 230 MeV has become canonical for all proton therapy accelerators. Similar application of a carbon beam requires ion energy of 430 MeV/u. Due to application of superconducting coils the magnetic field in these machines can reach 4-5 T and even 9 T in some cases. Medical cyclotrons with an ironless or nearly ironless magnetic system that have a number of advantages over the classical accelerators are in the development stage. In this work an attempt is made to describe some conceptual and technical features of modern accelerators under consideration. The emphasis is placed on the magnetic and acceleration systems along with the beam extraction unit, which are very important from the point of view of the facility compactness and compliance with the strict medical requirements.

  20. The use of high-density concretes in radiotherapy treatment room design.

    Science.gov (United States)

    Facure, A; Silva, A X

    2007-09-01

    With the modernization of radiotherapic centers, medical linear accelerators are largely replacing (60)Co teletherapy units. In many cases, the same vault housing the (60)Co teletherapy unit is reused for the linear accelerator and, when space is at a premium, high-density concrete (3.0-5.0 g/cm(3)) is employed to provide shielding against the primary, scatter and leakage radiation. This work presents a study based on Monte Carlo simulations of transmission of some clinical photon spectra (of 4-10 MV accelerators) through some types of high-density concretes, normally used in the construction of radiotherapy bunkers. From the simulations, the initial and subsequent tenth-value layers (TVL) for these materials, taking into account realistic clinical photon spectra, are presented, for primary radiation.

  1. The Accelerator Reliability Forum

    CERN Document Server

    Lüdeke, Andreas; Giachino, R

    2014-01-01

    A high reliability is a very important goal for most particle accelerators. The biennial Accelerator Reliability Workshop covers topics related to the design and operation of particle accelerators with a high reliability. In order to optimize the over-all reliability of an accelerator one needs to gather information on the reliability of many different subsystems. While a biennial workshop can serve as a platform for the exchange of such information, the authors aimed to provide a further channel to allow for a more timely communication: the Particle Accelerator Reliability Forum [1]. This contribution will describe the forum and advertise it’s usage in the community.

  2. Radiotherapy for pain management of bone metastases

    Energy Technology Data Exchange (ETDEWEB)

    Rezende Junior, Ismar de; Mattos, Marcos Duarte de; Nakamura, Ricardo; Lemes Junior, Joaquim; Vanzelli, Talita Lozano, E-mail: rezende.med@terra.com.br [Radioterapia do Hospital de Cancer de Barretos, SP (Brazil)

    2011-07-01

    Purpose: This is the first Brazilian study intended to evaluate the response of pain relief with radiotherapy in three different fractionation and the clinical differences in managing pain in patients with painful bone metastases. Methods: Prospective study of patients with painful bone metastases referred to the Radiotherapy Sector of the Hospital de Cancer de Barretos for pain-relieving radiotherapy between March and December 2010. It is known that radiotherapy seems to alter the activation of osteoclast-mediated bone resorption, relieving pain in cases of painful bone metastases. Patients were assessed in relation to the status of pain intensity before and after the initiation of radiotherapy. Either a single fraction of 8Gy, five fractions of 4Gy or ten fractions of 3Gy were given. A visual analog scale (VAS) was applied by doctors, nurses and nursing technicians to assess pain intensity at each session of radiotherapy, and follow-up at 8, 30 and 90 days from the end of treatment. Results: We evaluated 92 consecutive patients, 48 male and 44 female, with a median age of 58 years. We found that 14% of patients referred from the Palliative Care or Clinical Oncology sectors need better pharmacological analgesia due to severe pain, compared with 40.5% of patients from the other sectors (p = 0.004). We also found that the onset of pain relief to patients receiving 10 fractions of 300cGy analgesia without changing the pre-radiotherapy analgesia occurred with significance after the fifth fraction. Improvement in pain experienced within 90 days of follow-up was found in eighty percent of patients, independent of fractionated radiotherapy, site of metastases and the clinical condition of the patient. Discussion/Conclusion: The Palliative Care and Clinical Oncology sectors expressed greater concern in regards to analgesia for the patient with painful bone metastases. Radiotherapy is an effective pain-relieving treatment in different fractionation studied, even though the

  3. Spatially fractionated radiotherapy (GRID) using helical tomotherapy.

    Science.gov (United States)

    Zhang, Xin; Penagaricano, Jose; Yan, Yulong; Liang, Xiaoying; Morrill, Steven; Griffin, Robert J; Corry, Peter; Ratanatharathorn, Vaneerat

    2016-01-08

    Spatially fractionated radiotherapy (GRID) was designed to treat large tumors while sparing skin, and it is usually delivered with a linear accelerator using a commercially available block or multileaf collimator (LINAC-GRID). For deep-seated (skin to tumor distance (> 8 cm)) tumors, it is always a challenge to achieve adequate tumor dose coverage. A novel method to perform GRID treatment using helical tomotherapy (HT-GRID) was developed at our institution. Our approach allows treating patients by generating a patient-specific virtual GRID block (software-generated) and using IMRT technique to optimize the treatment plan. Here, we report our initial clinical experience using HT-GRID, and dosimetric comparison results between HT-GRID and LINAC-GRID. This study evaluates 10 previously treated patients who had deep-seated bulky tumors with complex geometries. Five of these patients were treated with HT-GRID and replanned with LINAC-GRID for comparison. Similarly, five other patients were treated with LINAC-GRID and replanned with HT-GRID for comparison. The prescription was set such that the maximum dose to the GTV is 20 Gy in a single fraction. Dosimetric parameters compared included: mean GTV dose (DGTV mean), GTV dose inhomogeneity (valley-to-peak dose ratio (VPR)), normal tissue doses (DNmean), and other organs-at-risk (OARs) doses. In addition, equivalent uniform doses (EUD) for both GTV and normal tissue were evaluated. In summary, HT-GRID technique is patient-specific, and allows adjustment of the GRID pattern to match different tumor sizes and shapes when they are deep-seated and cannot be adequately treated with LINAC-GRID. HT-GRID delivers a higher DGTV mean, EUD, and VPR compared to LINAC-GRID. HT-GRID delivers a higher DNmean and lower EUD for normal tissue compared to LINAC-GRID. HT-GRID plans also have more options for tumors with complex anatomical relationships between the GTV and the avoidance OARs (abutment or close proximity).

  4. Recent progress and future plans of heavy-ion cancer radiotherapy with HIMAC

    Science.gov (United States)

    Noda, K.; Furukawa, T.; Fujimoto, T.; Hara, Y.; Inaniwa, T.; Iwata, Y.; Katagiri, K.; Kanematsu, N.; Mizushima, K.; Mori, S.; Saotome, N.; Saraya, Y.; Sato, S.; Shirai, T.; Takada, M.; Takei, Y.; Tansyo, R.; Yonai, S.

    2017-09-01

    The HIMAC clinical study has been conducted with a carbon-ion beam since June 1994. Since 2006, as a new treatment research project, NIRS has developed both the accelerator and beam-delivery technologies for the sophisticated heavy-ion radiotherapy, which brings a pencil-beam 3D rescanning technology for both the static and moving-tumor treatments. In this technology, the depth-scanning technique was improved to the full-energy depth scanning by realizing a variable-energy operation of the HIMAC synchrotron itself. At present, a heavy-ion rotating gantry has been developed with the superconducting technology and is in a beam-commissioning stage. As a future plan, we just start a study of a multi-ions irradiation for more sophisticated LET-painting and a design study of a superconducting synchrotron for more compact heavy-ion radiotherapy facility.

  5. Comportamiento metabólico en el periparto de vacas Hartón del Valle, bajo condiciones de trópico bajo

    Directory of Open Access Journals (Sweden)

    Campos Gaona Rómulo

    2011-03-01

    Full Text Available

    El periodo de periparto o periodo de transición presenta variaciones fisiológicas significativas que inciden en posteriores sucesos productivos (pico de lactancia, reactivación ovárica. El ganado Hartón posee una excelente eficiencia reproductiva (estrecho intervalo entre partos, factor  que podría  originarse  en procesos  metabólicos  relacionados  con un mejor  ajuste homeostãtico. El principal objetivo del presente trabajo fue evaluar la homeostasis en una raza bovina criolla durante el periodo postparto. Para el estudio se emplearon 10 vacas multiparas, muestreadas antes del parto (dias 30 y 15 preparto y diariamente en los tres primeros dias del parto; posteriormente a partir del dia 5, con intervalos de cinco días y hasta el día 60 postparto. En total para cada animal se analizaron 14 muestras, cada una de ellas correspondió a un periodo analítico. Mediante venipunción coccígea en tubos al vacío con y sin anticoagulante se colectó la muestra de sangre completa. Por centrifugación se obtuvo plasma y suero, los cuales fueron almacenados a -20°C, hasta su análisis. Las determinaciones de hormonas se realizaron mediante radioinmunoanálisis  (RIA de fase sólida. A través de pruebas enzimáticas colorimétricas en equipos automatizados, se determinaron los valores de los metabolitos para cada uno de los periodos definidos. Los valores medios fueron: BHB (f3-Hidroxibutirato  0.39  mmol/L,  NEFA  (Ácidos  Grasos  No  Esterificados  0.76  mmol/L, triglicéridos 0.42 mmol/L, colesterol 2.43 mmol/L, insulina 4.77 pUl/ml, triyodotironina (T32.69 nmol/L, tetrayodotironina (T4 57.37 nmol/L, progesterona 5.54 nmol/L, cortisol 32.42 nmol/L. Los valores obtenidos para los diferentes metabolitos se encuentran dentro de los rangos reportados por la literatura para bovinos en condiciones tropicales.

  6. Genetic variability of Harton del Valle by RAM Variabilidad genética de Hartón del Valle mediante RAM

    Directory of Open Access Journals (Sweden)

    Alvarez Franco Luz Angela

    2008-03-01

    Full Text Available Harton del Valle (HV breed belong to the seven Creole breeds of the Colombian bovine livestock, according to FAO criteria it is considered as vulnerable. To study its genetical variability, 33 HV animals and three and 3 animals of Holstein breed as a external control were sampled. Simples of DNA were isolated using the Salting Out method and RAM (Random amplified microsatellites technique was used. CGA, CCA, TG and CT primers were used. The mean value of expected heterocigozity was 0.26 and FST fue 0.39 ± 0.03. Using Dice–Nei Li index and UPGMA clustering method, two groups were distinguished: the first one integrated for two conservation herds and other one by tour faros that have been sharing breeding bulls.El Hartón del Valle (HV hace parte de las siete razas criollas de ganado bovino colombiano y de acuerdo con los criterios de la FAO está considerado como vulnerable. Para estudiar su variabilidad genética fueron muestreados 33 individuos HV y tres animales de la raza Holstein, como control externo. Se extrajo ADN utilizando el método de Salting Out y las muestras fueron analizadas mediante la técnica molecular RAM (Randon amplified microsatellites. Se utilizaron los cebadores CGA, CCA, TG, y CT. El valor promedio de heterocigosidad esperada fue de 0.26 y el FST fue 0.39 ± 0.03. Con el índice de Dice–Nei Li y agrupando con el método UPGMA se distinguieron dos grupos: uno integrado por dos hatos de conservación y el otro por cuatro fincas que han compartido reproductores.

  7. Efecto de la edad de cosecha en las características poscosecha del plátano Dominico-Hartón (Musa AAB Simmonds

    Directory of Open Access Journals (Sweden)

    Luis Fernando Mejía-Gutiérrez

    2012-12-01

    Full Text Available En el departamento de Caldas, Colombia, se realizó la caracterización física, química y fisiológica durante las fases de cosecha y poscosecha del plátano Dominico Hartón (Musa AAB Simmonds cultivado en el municipio de Belalcázar. La investigación se hizo con frutos de 14, 16 y 18 semanas después de la floración. Cada 2 días y hasta senescencia se evaluaron los cambios de peso, firmeza, parámetros de color L*a*b*, relación pulpa/cáscara, índice de madurez, pH, humedad, almidones, índice de respiración y tasa de etileno. En este trabajo se utilizó un diseño longitudinal de medidas repetidas, balanceado, con un factor en tres niveles. El factor evaluado fue el tiempo de cosecha y las variables de respuesta fueron los parámetros fisicoquímicos. Los resultados mostraron variación en peso cercanas a 7%, el parámetro de color tinte varió entre -61.46 y 86.74, el croma entre 26.31 y 37.11 y el DE entre 1.4603 y 8.360, el pH varió entre 6.2 y 3.98, una relación pulpa/cáscara entre 2.53 y 4.11, la relación °brix/ acidez entre 11.36 y 26.2, la humedad entre 60.56% y 56%, el almidón entre 51.7% y 67% de MS, la tasa de producción de CO2 entre 3.4 y 8.9 g/kg por hora, el etileno entre 24 y 225 µlt/kg por hora. Los parámetros de maduración mostraron comportamiento climatérico y los días a maduración total fueron de 9, 14 y 21 para los frutos de 18, 16 y 14 semanas desde floración.

  8. How to irradiate bone metastases?; Radiotherapie des metastases osseuses: quel est le meilleur schema de radiotherapie?

    Energy Technology Data Exchange (ETDEWEB)

    Pradier, O.; Bouchekoua, M.; Albargach, N.; Muller, M.; Malhaire, J.P. [Centre Hospitalier Universitaire, Service de Radiotherapie, Institut de Cancerologie et d' Hematologie, 29 - Brest (France)

    2008-12-15

    Radiotherapy for bone metastases represents an important part of daily practice in our departments of radiotherapy. Majority of treatments deliver either one fraction (6 to 10 Gy) or multi-fractions mainly using 30 Gy in ten fractions. In the past decade, several randomized trials aimed to determine the optimal scheme of radiotherapy in this setting. In the present review, the efficacy of radiotherapy on bone metastases will be evaluated using the following parameters: the partial or complete responses on pain, the reduction of antalgic intake, bone re-calcification, and need for reirradiation. Other parameters must also be considered, such as the primary site, number of metastasis, performance status, overall prognosis and side effects of radiotherapy. (authors)

  9. Industrial Application of Accelerators

    CERN Document Server

    CERN. Geneva

    2017-01-01

    At CERN, we are very familiar with large, high energy particle accelerators. However, in the world outside CERN, there are more than 35000 accelerators which are used for applications ranging from treating cancer, through making better electronics to removing harmful micro-organisms from food and water. These are responsible for around $0.5T of commerce each year. Almost all are less than 20 MeV and most use accelerator types that are somewhat different from what is at CERN. These lectures will describe some of the most common applications, some of the newer applications in development and the accelerator technology used for them. It will also show examples of where technology developed for particle physics is now being studied for these applications. Rob Edgecock is a Professor of Accelerator Science, with a particular interest in the medical applications of accelerators. He works jointly for the STFC Rutherford Appleton Laboratory and the International Institute for Accelerator Applications at the Univer...

  10. Industrial Application of Accelerators

    CERN Document Server

    CERN. Geneva

    2017-01-01

    At CERN, we are very familiar with large, high energy particle accelerators. However, in the world outside CERN, there are more than 35000 accelerators which are used for applications ranging from treating cancer, through making better electronics to removing harmful micro-organisms from food and water. These are responsible for around $0.5T of commerce each year. Almost all are less than 20 MeV and most use accelerator types that are somewhat different from what is at CERN. These lectures will describe some of the most common applications, some of the newer applications in development and the accelerator technology used for them. It will also show examples of where technology developed for particle physics is now being studied for these applications. Rob Edgecock is a Professor of Accelerator Science, with a particular interest in the medical applications of accelerators. He works jointly for the STFC Rutherford Appleton Laboratory and the International Institute for Accelerator Applications at the Uni...

  11. Acceleration in astrophysics

    Energy Technology Data Exchange (ETDEWEB)

    Colgate, S.A.

    1993-12-31

    The origin of cosmic rays and applicable laboratory experiments are discussed. Some of the problems of shock acceleration for the production of cosmic rays are discussed in the context of astrophysical conditions. These are: The presumed unique explanation of the power law spectrum is shown instead to be a universal property of all lossy accelerators; the extraordinary isotropy of cosmic rays and the limited diffusion distances implied by supernova induced shock acceleration requires a more frequent and space-filling source than supernovae; the near perfect adiabaticity of strong hydromagnetic turbulence necessary for reflecting the accelerated particles each doubling in energy roughly 10{sup 5} to {sup 6} scatterings with negligible energy loss seems most unlikely; the evidence for acceleration due to quasi-parallel heliosphere shocks is weak. There is small evidence for the expected strong hydromagnetic turbulence, and instead, only a small number of particles accelerate after only a few shock traversals; the acceleration of electrons in the same collisionless shock that accelerates ions is difficult to reconcile with the theoretical picture of strong hydromagnetic turbulence that reflects the ions. The hydromagnetic turbulence will appear adiabatic to the electrons at their much higher Larmor frequency and so the electrons should not be scattered incoherently as they must be for acceleration. Therefore the electrons must be accelerated by a different mechanism. This is unsatisfactory, because wherever electrons are accelerated these sites, observed in radio emission, may accelerate ions more favorably. The acceleration is coherent provided the reconnection is coherent, in which case the total flux, as for example of collimated radio sources, predicts single charge accelerated energies much greater than observed.

  12. Radiotherapy in stage 1 testicular seminoma: retrospective study and review of literature; Radiotherapie des seminomes testiculaires de stade 1: etude retrospective et revue de la litterature

    Energy Technology Data Exchange (ETDEWEB)

    Bauduceau, O.; Le-Moulec, S.; Bernard, O. [Hopital des Armees du Val-de-Grace, Service de Radiotherapie et Oncologie, 75 - Paris (France); Souleau, B. [Hopital des Armees Percy, Service d' Hematologie, 92 - Clamart (France); Houlgatte, A. [Hopital des Armees du Val-de-Grace, Service d' Urologie, 75 - Paris (France)

    2003-12-01

    Introduction. - Seminoma accounts for about 40% of germ cell tumours of the testicle. In this retrospective analysis, we review literature concerning management of stage I seminoma. Materials and methods. - Between March 1987 and April 2001, 65 patients with stage I pure testicular seminoma received adjuvant radiotherapy with a 25 MV linear accelerator. Results. - Median age was 33 years. Testicular tumour has been found on the right testis in 39 patients and on the left one in 24 patients. Patients have been treated using an anterior-posterior parallel pair and have received 20-25 Gy in 10-14 fractions. The target volume consisted of paraaortic, and paraaortic + homolateral iliac lymph nodes in 17 and 46 patients, respectively. Acute toxicity was mainly digestive, 38% of patients presenting nausea and vomiting. Median follow-up time was 37 months. All patients are alive in complete remission. Discussion. - Because of good radio-sensitivity of seminoma, radiotherapy is regarded as standard adjuvant treatment (5 years relapse rate: 3-5%). Acute toxicity is dominated by moderate gastro-intestinal side effects. Secondary neoplasia represents one of the worst possible long-term complications of therapy. Waiting for ongoing randomized trials, the modern literature for seminoma reflects a trend toward lower radiation doses (20-25 Gy) and smaller treatment volumes (paraaortic field). Adjuvant chemotherapy with two courses of carbo-platin, might be equivalent to radiotherapy but must be investigated in randomized trials. A surveillance policy is one of the other management options less recommended. (author)

  13. Radiotherapy Treatment Planning for Testicular Seminoma

    Energy Technology Data Exchange (ETDEWEB)

    Wilder, Richard B., E-mail: richardbwilder@yahoo.com [Department of Radiation Oncology, Moffitt Cancer Center, Tampa, FL (United States); Buyyounouski, Mark K. [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States); Efstathiou, Jason A. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA (United States); Beard, Clair J. [Department of Radiation Oncology, Dana-Farber/Brigham and Women' s Cancer Center, Boston, MA (United States)

    2012-07-15

    Virtually all patients with Stage I testicular seminoma are cured regardless of postorchiectomy management. For patients treated with adjuvant radiotherapy, late toxicity is a major concern. However, toxicity may be limited by radiotherapy techniques that minimize radiation exposure of healthy normal tissues. This article is an evidence-based review that provides radiotherapy treatment planning recommendations for testicular seminoma. The minority of Stage I patients who choose adjuvant treatment over surveillance may be considered for (1) para-aortic irradiation to 20 Gy in 10 fractions, or (2) carboplatin chemotherapy consisting of area under the curve, AUC = 7 Multiplication-Sign 1-2 cycles. Two-dimensional radiotherapy based on bony anatomy is a simple and effective treatment for Stage IIA or IIB testicular seminoma. Centers with expertise in vascular and nodal anatomy may consider use of anteroposterior-posteroanterior fields based on three-dimensional conformal radiotherapy instead. For modified dog-leg fields delivering 20 Gy in 10 fractions, clinical studies support placement of the inferior border at the top of the acetabulum. Clinical and nodal mapping studies support placement of the superior border of all radiotherapy fields at the top of the T12 vertebral body. For Stage IIA and IIB patients, an anteroposterior-posteroanterior boost is then delivered to the adenopathy with a 2-cm margin to the block edge. The boost dose consists of 10 Gy in 5 fractions for Stage IIA and 16 Gy in 8 fractions for Stage IIB. Alternatively, bleomycin, etoposide, and cisplatin chemotherapy for 3 cycles or etoposide and cisplatin chemotherapy for 4 cycles may be delivered to Stage IIA or IIB patients (e.g., if they have a horseshoe kidney, inflammatory bowel disease, or a history of radiotherapy).

  14. Accelerated fractionation in advanced head and neck cancer

    Energy Technology Data Exchange (ETDEWEB)

    Olmi, P.; Cellai, E. (Florence University (Italy). Department of Radiotherapy); Chiavacci, A.; Fablai, C. (Florence Hospital (Italy). Department of Radiotherapy)

    1990-03-01

    From 1975 to 1985, 161 patients affected by head and neck cancer (58 oropharynx, 67 oral cavity, 36 paranasal sinuses) were treated with radiotherapy using an accelerated fractionation (AF) schedule at the University and Hospital Radiotherapy Departments of Florence. Five-year actuarial local control and survival was 38% for the oropharynx, 18% and 20% for the oral cavity, and 38% and 31% for the paranasal sinuses. Results were analysed according to T and N stage as well. Severe late sequelae were evaluated in 53 patients without local disease and with a minimum follow-up of one year: 8 patients developed osteonecrosis; there were 3 cases of trismus, 2 cases of laryngeal oedema, one case of blindness and one case of opththalmitis. (author). 19 refs.; 2 figs.; 9 tabs.

  15. Implementation of a risk assessment tool based on a probabilistic safety assessment developed for radiotherapy practices

    Energy Technology Data Exchange (ETDEWEB)

    Paz, A.; Godinez, V.; Lopez, R., E-mail: abpaz@cnsns.gob.m [Comision Nacional de Seguridad Nuclear y Salvaguardias, Dr. Barragan No. 779, Col. Narvarte, 03020 Mexico D. F. (Mexico)

    2010-10-15

    The present work describes the implementation process and main results of the risk assessment to the radiotherapy practices with Linear Accelerators (Linac), with cobalt 60, and with brachytherapy. These evaluations were made throughout the risk assessment tool for radiotherapy practices SEVRRA (risk evaluation system for radiotherapy), developed at the Mexican National Commission in Nuclear Safety and Safeguards derived from the outcome obtained with the Probabilistic Safety Analysis developed at the Ibero-American Regulators Forum for these radiotherapy facilities. The methodology used is supported by risk matrices method, a mathematical tool that estimates the risk to the patient, radiation workers and public from mechanical failures, mis calibration of the devices, human mistakes, and so. The initiating events are defined as those undesirable events that, together with other failures, can produce a delivery of an over-dose or an under-dose of the medical prescribed dose, to the planned target volume, or a significant dose to non prescribed human organs. Initiating events frequency and reducer of its frequency (actions intended to avoid the accident) are estimated as well as robustness of barriers to those actions, such as mechanical switches, which detect and prevent the accident from occurring. The spectrum of the consequences is parameterized, and the actions performed to reduce the consequences are identified. Based on this analysis, a software tool was developed in order to simplify the evaluations to radiotherapy installations and it has been applied as a first step forward to some Mexican installations, as part of a national implementation process, the final goal is evaluation of all Mexican facilities in the near future. The main target and benefits of the SEVRRA implementation are presented in this paper. (Author)

  16. Pulse-resolved radiotherapy dosimetry using fiber-coupled organic scintillators

    Energy Technology Data Exchange (ETDEWEB)

    Ravnsborg Beierholm, A.

    2011-05-15

    This PhD project pertains to the development and adaptation of a dosimetry system that can be used to verify the delivery of radiation in modern radiotherapy modalities involving small radiation fields and dynamic radiation delivery. The dosimetry system is based on fibre-coupled organic scintillators and can be perceived as a well characterized, independent alternative to the methods that are in clinical use today. The dosimeter itself does not require a voltage supply, and is composed of water equivalent materials. The dosimeter can be fabricated with a sensitive volume smaller than a cubic millimeter, which is small enough to resolve the small radiation fields encountered in modern radiotherapy. The fast readout of the dosimeter enables measurements on the same time scale as the pulsed radiation delivery from the medical linear accelerators used for treatment. The dosimetry system, comprising fiber-coupled organic scintillators and data acquisition hardware, was developed at the Radiation Research Division at Risoe DTU and tested using clinical x-ray beams at hospitals in Denmark and abroad. Measurements of output factors and percentage depth dose were performed and compared with reference values and Monte Carlo simulations for static square radiation fields for standard (4 cm x 4 cm to 20 cm x 20 cm) and small (down to 0.6 cm x 0.6 cm) field sizes. The accuracy of most of the obtained measurements was good, agreeing with reference and simulated dose values to within 2 % standard deviation for both standard and small fields. This thesis concludes that the new pulse-resolved dosimetry system holds great potential for modern radiotherapy applications, such as stereotactic radiotherapy and intensity-modulated radiotherapy. (Author)

  17. Post Pelvic Radiotherapy Bony Changes

    Energy Technology Data Exchange (ETDEWEB)

    Huh, Seung Jae [Samsung Medical Center, Seoul (Korea, Republic of)

    2009-03-15

    There has been recent interest in radiation-induced bone injury in clinical conditions, especially for pelvic insufficiency fracture (PIF). A PIF is caused by the effect of normal or physiological stress on bone with demineralization and decreased elastic resistance. Pelvic radiotherapy (RT) can also contribute to the development of a PIF. A PIF has been regarded as a rare complication with the use of megavoltage equipment. However, recent studies have reported the incidence of PIFs as 8.2{approx}20% after pelvic RT in gynecological patients, an incidence that was higher than previously believed. The importance of understanding a PIF lies in the potential for misdiagnosis as a bony metastasis. If patients complain of pelvic pain after whole-pelvis radiation therapy, the presence of a PIF must be considered in the differential diagnosis. The use of multibeam arrangements and conformal RT to reduce the volume and dose of irradiated pelvic bone can be helpful to minimize the risk of fracture. In addition to a PIF, osteonecrosis and avascular necrosis of the femoral head can develop after radiation therapy. Osteoradionecrosis of the pelvic bone is a clinical diagnostic challenge that must be differentiated from an osseous metastasis. A post-radiation bone sarcoma can result as a long-term sequela of pelvic irradiation for uterine cervical cancer.

  18. [Dosimetric characteristics of the bremsstrahlung beam from the LUE-15M medical linear electron accelerator].

    Science.gov (United States)

    Vatnitskiĭ, S M; Ermakov, I A; Puzanov, V P; Sinitsyn, R V; Cherviakov, A M

    1983-10-01

    The paper presents methods and results of a study of radiation-physical characteristics of inhibitory radiation beam with the Grenz energy of 15MeV generated by an electron linear accelerator LUE-15M. Special emphasis is laid on primary dosimetric information used for the planning of radiotherapy: depth doses, beam profiles, dose functions of a collimated beam. It has been shown that in general the accelerator meets the requirements of the International Electrotechnical Commission. General error in the focal absorbed dose at the expense of variable parameters of the accelerator was evaluated. It does not exceed +/- 3.5%.

  19. HYDRAULICS, HART COUNTY, KENTUCKY, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Recent developments in digital terrain and geospatial database management technology make it possible to protect this investment for existing and future projects to...

  20. Het hart van de kerk

    Directory of Open Access Journals (Sweden)

    Gysbert Dos

    1998-01-01

    Full Text Available The heart of the church. Abraham Kuyper accused the so-called 'ethische' theologians that they only pretended to be Calvinists because the doctrine of predestination did not figure as a central point of their thinking. In this paper the answer of J H Gunning Jr, one of the leaders of the so-called 'ethischen',  to Kuyper is discussed. Although this paper mainly focuses on six articles Gunning published in the periodical 'Stemmen voor waarheid en vrede' between 1878 and 1880, it also introduces other articles of Gunning into the discussion. The topic of this paper indicates how, in the end, Gunning saw predestination.

  1. Peilstationsproject Hart- en vaatziekten 1990

    NARCIS (Netherlands)

    Kromhout D; Obermann-de Boer GL; Blokstra A; Verschuren WMM

    1991-01-01

    The aim of this project is to study trends in the major risk factors for cardiovascular diseases e.g. total and HDL cholesterol, blood pressure and smoking. Also the importance of less frequently measured risk factors e.g. contraceptive pill use and psycho-social factors in the etiology of cardio

  2. Peilstationsproject Hart- en Vaatziekten 1991

    NARCIS (Netherlands)

    Kromhout D; Obermann-de Boer GL; Blokstra A; Verschuren WMM; Seidell J; Bueno de Mesquita HB; Smit HA

    1992-01-01

    The aim of this project is to study trends in the major risk factors for cardiovascular diseases e.g. total and HDL cholesterol, blood pressure and smoking. Also the importance of less frequently measured risk factors e.g. contraceptive pill use and psycho-social factors in the etiology of cardio

  3. Peilstationsproject Hart- en vaatziekten 1989

    NARCIS (Netherlands)

    Kromhout D; Obermann-de Boer GL; Blokstra A; Verschuren WMM

    1990-01-01

    The aim of this project is to study trends in the major risk factors for cardiovascular diseases e.g. total and HDL cholesterol, blood pressure and smoking. Also the importance of less frequently measured risk factors e.g. contraceptive pill use and psycho-social factors in the etiology of cardio

  4. A review of ion sources for medical accelerators (invited).

    Science.gov (United States)

    Muramatsu, M; Kitagawa, A

    2012-02-01

    There are two major medical applications of ion accelerators. One is a production of short-lived isotopes for radionuclide imaging with positron emission tomography and single photon emission computer tomography. Generally, a combination of a source for negative ions (usually H- and/or D-) and a cyclotron is used; this system is well established and distributed over the world. Other important medical application is charged-particle radiotherapy, where the accelerated ion beam itself is being used for patient treatment. Two distinctly different methods are being applied: either with protons or with heavy-ions (mostly carbon ions). Proton radiotherapy for deep-seated tumors has become widespread since the 1990s. The energy and intensity are typically over 200 MeV and several 10(10) pps, respectively. Cyclotrons as well as synchrotrons are utilized. The ion source for the cyclotron is generally similar to the type for production of radioisotopes. For a synchrotron, one applies a positive ion source in combination with an injector linac. Carbon ion radiotherapy awakens a worldwide interest. About 6000 cancer patients have already been treated with carbon beams from the Heavy Ion Medical Accelerator in Chiba at the National Institute of Radiological Sciences in Japan. These clinical results have clearly verified the advantages of carbon ions. Heidelberg Ion Therapy Center and Gunma University Heavy Ion Medical Center have been successfully launched. Several new facilities are under commissioning or construction. The beam energy is adjusted to the depth of tumors. It is usually between 140 and 430 MeV∕u. Although the beam intensity depends on the irradiation method, it is typically several 10(8) or 10(9) pps. Synchrotrons are only utilized for carbon ion radiotherapy. An ECR ion source supplies multi-charged carbon ions for this requirement. Some other medical applications with ion beams attract developer's interests. For example, the several types of accelerators are

  5. Particle-accelerator decommissioning

    Energy Technology Data Exchange (ETDEWEB)

    Opelka, J.H.; Mundis, R.L.; Marmer, G.J.; Peterson, J.M.; Siskind, B.; Kikta, M.J.

    1979-12-01

    Generic considerations involved in decommissioning particle accelerators are examined. There are presently several hundred accelerators operating in the United States that can produce material containing nonnegligible residual radioactivity. Residual radioactivity after final shutdown is generally short-lived induced activity and is localized in hot spots around the beam line. The decommissioning options addressed are mothballing, entombment, dismantlement with interim storage, and dismantlement with disposal. The recycle of components or entire accelerators following dismantlement is a definite possibility and has occurred in the past. Accelerator components can be recycled either immediately at accelerator shutdown or following a period of storage, depending on the nature of induced activation. Considerations of cost, radioactive waste, and radiological health are presented for four prototypic accelerators. Prototypes considered range from small accelerators having minimal amounts of radioactive mmaterial to a very large accelerator having massive components containing nonnegligible amounts of induced activation. Archival information on past decommissionings is presented, and recommendations concerning regulations and accelerator design that will aid in the decommissioning of an accelerator are given.

  6. A systematic review of antiproton radiotherapy

    Directory of Open Access Journals (Sweden)

    Martin-Immanuel eBittner

    2014-01-01

    Full Text Available Antiprotons have been proposed as possible particles for radiotherapy; over the past years, the renewed interest in the potential biomedical relevance led to an increased research activity. It is the aim of this review to deliver a comprehensive overview regarding the evidence accumulated so far, analysing the background and depicting the current status of antiprotons in radiotherapy. A literature search has been conducted, including major scientific and commercial databases. All articles and a number of relevant conference abstracts published in the respective field have been included in this systematic review. The physical basis of antiproton radiotherapy is complex; however, the characterisation of the energy deposition profile supports its potential use in radiotherapy. Also the dosimetry improved considerably over the past few years. Regarding the biological properties, data on the effects on cells are presented; however, definite conclusions regarding the relative biological effectiveness cannot be made at the moment and radiobiological evidence of enhanced effectiveness remains scarce. In addition, there is new evidence supporting the potential imaging properties, for example for online dose verification. Clinical settings which might profit from the use of antiprotons have been further tracked. Judging from the evidence available so far, clinical constellations requiring optimal sparing in the entrance region of the beam and re-irradiations might profit most from antiproton radiotherapy. While several open questions remain to be answered, first steps towards a thorough characterisation of this interesting modality have been made.

  7. Clinical efficacy of radiotherapy combined with sodium glycididazole ...

    African Journals Online (AJOL)

    Purpose: To assess the clinical efficacy and side effects of radiotherapy combined with sodium glycididazole in ... effect in the treatment of recurrent oesophageal carcinoma than radiotherapy alone. Keywords: ..... Chen J, Zhou ZR. Research ...

  8. Postoperative radiotherapy of glioblastoma multiforme. Analysis and critical assessment of different treatment strategies and predictive factors

    Energy Technology Data Exchange (ETDEWEB)

    Piroth, M.D.; Gagel, B.; Pinkawa, M.; Asadpour, B.; Eble, M.J. [Dept. of Radiation Oncology, RWTH Aachen Univ. Hospital, Aachen (Germany); Stanzel, S. [Inst. of Medical Statistics, RWTH Aachen Univ. Hospital, Aachen (Germany)

    2007-12-15

    Background and Purpose: Different factors influence glioblastoma patients' prognosis. The aim of this retrospective, explorative analysis was to define the role of recent treatment strategies and to examine the value of different prognostic factors. Patients and Methods: A total of 110 patients was analyzed. Complete resection, partial resection, and biopsy was accomplished in 69, 22, and 19 patients, respectively. 56 patients received conventionally fractionated radiotherapy with a median total dose of 60 Gy, 2 Gy daily. 54 patients received hyperfractionated accelerated radiotherapy with a median total dose of 54 Gy, 2 x 1.8 Gy daily. 20 patients had concomitant temozolomide (50-75 mg/m{sup 2}/d), and 20 patients concomitant topotecan (0.5 mg/m{sup 2} as continuous venous infusion over 21 days). 37 patients received temozolomide as salvage therapy. Results: Median overall (OS) and disease-free survival (DFS) were 8.7 and 4.8 months. After complete resection, partial resection, and biopsy, OS was 9.5, 8.5, and 5.5 months, respectively. OS was 8.5, 13.8, and 8.2 months for radiotherapy alone, concomitant temozolomide, and concomitant topotecan, respectively. Hazard ratio was 0.29 (OS; p = 0.002) and 0.32 (DFS; p = 0.003) for concomitant temozolomide compared to radiotherapy alone. Topotecan led to an increased toxicity. With 9.7 months for conventionally fractionated radiotherapy and 8.1 months for hyperfractionated radiotherapy, OS differed significantly (p = 0.003, log-rank test). OS in patients with RPA (recursive partitioning analysis) score III, IV, V, and VI was 14.1, 10, 9.5, and 5.8 months (p = 0.003, log-rank test). In the univariate (p = 0.0001, log-rank test) and multivariate analysis (p = 0.002, Cox regression), salvage temozolomide led to a statistically significant survival benefit (10.6 vs. 7.7 months). Conclusion: Concomitant topotecan or the use of hyperfractionated radiotherapy did not show to be superior in outcome in this retrospective

  9. SU-E-T-501: Normal Tissue Toxicities of Pulsed Low Dose Rate Radiotherapy and Conventional Radiotherapy: An in Vivo Total Body Irradiation Study

    Energy Technology Data Exchange (ETDEWEB)

    Cvetkovic, D; Zhang, P; Wang, B; Chen, L; Ma, C [Fox Chase Cancer Center, Philadelphia, PA (United States)

    2014-06-01

    Purpose: Pulsed low dose rate radiotherapy (PLDR) is a re-irradiation technique for therapy of recurrent cancers. We have previously shown a significant difference in the weight and survival time between the mice treated with conventional radiotherapy (CRT) and PLDR using total body irradiation (TBI). The purpose of this study was to investigate the in vivo effects of PLDR on normal mouse tissues.Materials and Methods: Twenty two male BALB/c nude mice, 4 months of age, were randomly assigned into a PLDR group (n=10), a CRT group (n=10), and a non-irradiated control group (n=2). The Siemens Artiste accelerator with 6 MV photon beams was used. The mice received a total of 18Gy in 3 fractions with a 20day interval. The CRT group received the 6Gy dose continuously at a dose rate of 300 MU/min. The PLDR group was irradiated with 0.2Gyx20 pulses with a 3min interval between the pulses. The mice were weighed thrice weekly and sacrificed 2 weeks after the last treatment. Brain, heart, lung, liver, spleen, gastrointestinal, urinary and reproductive organs, and sternal bone marrow were removed, formalin-fixed, paraffin-embedded and stained with H and E. Morphological changes were observed under a microscope. Results: Histopathological examination revealed atrophy in several irradiated organs. The degree of atrophy was mild to moderate in the PLDR group, but severe in the CRT group. The most pronounced morphological abnormalities were in the immune and hematopoietic systems, namely spleen and bone marrow. Brain hemorrhage was seen in the CRT group, but not in the PLDR group. Conclusions: Our results showed that PLDR induced less toxicity in the normal mouse tissues than conventional radiotherapy for the same dose and regimen. Considering that PLDR produces equivalent tumor control as conventional radiotherapy, it would be a good modality for treatment of recurrent cancers.

  10. Leaky Fermi accelerators

    CERN Document Server

    Shah, Kushal; Rom-Kedar, Vered; Turaev, Dmitry

    2015-01-01

    A Fermi accelerator is a billiard with oscillating walls. A leaky accelerator interacts with an environment of an ideal gas at equilibrium by exchange of particles through a small hole on its boundary. Such interaction may heat the gas: we estimate the net energy flow through the hole under the assumption that the particles inside the billiard do not collide with each other and remain in the accelerator for sufficiently long time. The heat production is found to depend strongly on the type of the Fermi accelerator. An ergodic accelerator, i.e. one which has a single ergodic component, produces a weaker energy flow than a multi-component accelerator. Specifically, in the ergodic case the energy gain is independent of the hole size, whereas in the multi-component case the energy flow may be significantly increased by shrinking the hole size.

  11. Accelerator reliability workshop

    Energy Technology Data Exchange (ETDEWEB)

    Hardy, L.; Duru, Ph.; Koch, J.M.; Revol, J.L.; Van Vaerenbergh, P.; Volpe, A.M.; Clugnet, K.; Dely, A.; Goodhew, D

    2002-07-01

    About 80 experts attended this workshop, which brought together all accelerator communities: accelerator driven systems, X-ray sources, medical and industrial accelerators, spallation sources projects (American and European), nuclear physics, etc. With newly proposed accelerator applications such as nuclear waste transmutation, replacement of nuclear power plants and others. Reliability has now become a number one priority for accelerator designers. Every part of an accelerator facility from cryogenic systems to data storage via RF systems are concerned by reliability. This aspect is now taken into account in the design/budget phase, especially for projects whose goal is to reach no more than 10 interruptions per year. This document gathers the slides but not the proceedings of the workshop.

  12. Accelerator and radiation physics

    CERN Document Server

    Basu, Samita; Nandy, Maitreyee

    2013-01-01

    "Accelerator and radiation physics" encompasses radiation shielding design and strategies for hadron therapy accelerators, neutron facilities and laser based accelerators. A fascinating article describes detailed transport theory and its application to radiation transport. Detailed information on planning and design of a very high energy proton accelerator can be obtained from the article on radiological safety of J-PARC. Besides safety for proton accelerators, the book provides information on radiological safety issues for electron synchrotron and prevention and preparedness for radiological emergencies. Different methods for neutron dosimetry including LET based monitoring, time of flight spectrometry, track detectors are documented alongwith newly measured experimental data on radiation interaction with dyes, polymers, bones and other materials. Design of deuteron accelerator, shielding in beam line hutches in synchrotron and 14 MeV neutron generator, various radiation detection methods, their characteriza...

  13. Power Converters for Accelerators

    CERN Document Server

    Visintini, R

    2015-01-01

    Particle accelerators use a great variety of power converters for energizing their sub-systems; while the total number of power converters usually depends on the size of the accelerator or combination of accelerators (including the experimental setup), the characteristics of power converters depend on their loads and on the particle physics requirements: this paper aims to provide an overview of the magnet power converters in use in several facilities worldwide.

  14. Miniaturization Techniques for Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Spencer, James E.

    2003-05-27

    The possibility of laser driven accelerators [1] suggests the need for new structures based on micromachining and integrated circuit technology because of the comparable scales. Thus, we are exploring fully integrated structures including sources, optics (for both light and particle) and acceleration in a common format--an accelerator-on-chip (AOC). Tests suggest a number of preferred materials and techniques but no technical or fundamental roadblocks at scales of order 1 {micro}m or larger.

  15. FFAGS for rapid acceleration

    Energy Technology Data Exchange (ETDEWEB)

    Carol J. Johnstone and Shane Koscielniak

    2002-09-30

    When large transverse and longitudinal emittances are to be transported through a circular machine, extremely rapid acceleration holds the advantage that the beam becomes immune to nonlinear resonances because there is insufficient time for amplitudes to build up. Uncooled muon beams exhibit large emittances and require fast acceleration to avoid decay losses and would benefit from this style of acceleration. The approach here employs a fixed-field alternating gradient or FFAG magnet structure and a fixed frequency acceleration system. Acceptance is enhanced by the use only of linear lattice elements, and fixed-frequency rf enables the use of cavities with large shunt resistance and quality factor.

  16. FFAGS FOR MUON ACCELERATION.

    Energy Technology Data Exchange (ETDEWEB)

    BERG,J.S.KAHN,S.PALMER,R.TRBOJEVIC,D.JOHNSTONE,C.KEIL,Y.OGITSU,T.OHMORI,C.SESSLER,A.KOSCIELNIAK,S.

    2003-06-26

    Due to their finite lifetime, muons must be accelerated very rapidly. It is challenging to make the magnets ramp fast enough to accelerate in a synchrotron, and accelerating in a linac is very expensive. One can use a recirculating accelerator (like CEBAF), but one needs a different arc for each turn, and this limits the number of turns one can use to accelerate, and therefore requires significant amounts of RF to achieve the desired energy gain. An alternative method for muon acceleration is using a fixed field alternating gradient (FFAG) accelerator. Such an accelerator has a very large energy acceptance (a factor of two or three), allowing one to use the same arc with a magnetic field that is constant over time. Thus, one can in principle make as many turns as one can tolerate due to muon decay, therefore reducing the RF cost without increasing the arc cost. This paper reviews the current status of research into the design of FFAGs for muon acceleration. Several current designs are described and compared. General design considerations are also discussed.

  17. High Gradient Accelerator Research

    Energy Technology Data Exchange (ETDEWEB)

    Temkin, Richard [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Dept. of Physics. Plasma Science and Fusion Center

    2016-07-12

    The goal of the MIT program of research on high gradient acceleration is the development of advanced acceleration concepts that lead to a practical and affordable next generation linear collider at the TeV energy level. Other applications, which are more near-term, include accelerators for materials processing; medicine; defense; mining; security; and inspection. The specific goals of the MIT program are: • Pioneering theoretical research on advanced structures for high gradient acceleration, including photonic structures and metamaterial structures; evaluation of the wakefields in these advanced structures • Experimental research to demonstrate the properties of advanced structures both in low-power microwave cold test and high-power, high-gradient test at megawatt power levels • Experimental research on microwave breakdown at high gradient including studies of breakdown phenomena induced by RF electric fields and RF magnetic fields; development of new diagnostics of the breakdown process • Theoretical research on the physics and engineering features of RF vacuum breakdown • Maintaining and improving the Haimson / MIT 17 GHz accelerator, the highest frequency operational accelerator in the world, a unique facility for accelerator research • Providing the Haimson / MIT 17 GHz accelerator facility as a facility for outside users • Active participation in the US DOE program of High Gradient Collaboration, including joint work with SLAC and with Los Alamos National Laboratory; participation of MIT students in research at the national laboratories • Training the next generation of Ph. D. students in the field of accelerator physics.

  18. Radiotherapy-induced hypopituitarism: a review.

    Science.gov (United States)

    Sathyapalan, Thozhukat; Dixit, Sanjay

    2012-05-01

    Hypopituitarism is a disorder caused by impaired hormonal secretions from the hypothalamic-pituitary axis. Radiotherapy is the most common cause of iatrogenic hypopituitarism. The hypothalamic-pituitary axis inadvertently gets irradiated in patients receiving prophylactic cranial radiotherapy for leukemia, total body irradiation and radiotherapy for intracranial, base skull, sinonasal and nasopharyngeal tumors. Radiation-induced hypopituitarism (RIH) is insidious, progressive and largely nonreversible. Mostly, RIH involves one hypothalamic-pituitary axis; however, multiple hormonal axes deficiency starts developing at higher doses. Although the clinical effects of the hypopituitarism are more profound in children and young adults, its implications in older adults are being increasingly recognized. The risk continues to persist or increase up to 10 years following radiation exposure. The clinical management of hypopituitarism is challenging both for the patients and healthcare providers. Here we have reviewed the scale of the problem, the risk factors and the management of RIH.

  19. Pelvic radiotherapy and sexual dysfunction in women

    DEFF Research Database (Denmark)

    Jensen, Pernille Tine; Froeding, Ligita Paskeviciute

    2015-01-01

    of life (QOL) issues; sexual functioning has proved to be one of the most important aspects of concern in long-term survivors. METHODS: An updated literature search in PubMed was performed on pelvic radiotherapy and female sexual functioning/dysfunction. Studies on gynaecological, urological...... and gastrointestinal cancers were included. The focus was on the period from 2010 to 2014, on studies using PROs, on potential randomized controlled trials (RCTs) where female sexual dysfunction (FSD) at least constituted a secondary outcome, and on studies reporting from modern radiotherapy modalities. RESULTS...... during the next five years. Several newer studies confirm that health care professionals are still reluctant to discuss treatment induced sexual dysfunction with patients. CONCLUSIONS: Pelvic radiotherapy has a persistent deteriorating effect on the vaginal mucosa impacting negatively on the sexual...

  20. Estimating the Risks of Breast Cancer Radiotherapy

    DEFF Research Database (Denmark)

    Taylor, Carolyn; Correa, Candace; Duane, Frances K

    2017-01-01

    and cause-specific mortality and excess RRs (ERRs) per Gy for incident lung cancer and cardiac mortality. Smoking status was unavailable. Third, the lung or heart ERRs per Gy in the trials and the 2010 to 2015 doses were combined and applied to current smoker and nonsmoker lung cancer and cardiac mortality.......06) ERR per Gy whole-heart dose. Estimated absolute risks from modern radiotherapy were as follows: lung cancer, approximately 4% for long-term continuing smokers and 0.3% for nonsmokers; and cardiac mortality, approximately 1% for smokers and 0.3% for nonsmokers. Conclusion For long-term smokers......Purpose Radiotherapy reduces the absolute risk of breast cancer mortality by a few percentage points in suitable women but can cause a second cancer or heart disease decades later. We estimated the absolute long-term risks of modern breast cancer radiotherapy. Methods First, a systematic literature...

  1. [Radiotherapy of choroid metastases in breast carcinoma].

    Science.gov (United States)

    Dobrowsky, W; Schmid, A P; Dobrowsky, E

    1987-06-01

    From 1975 to 1984, thirteen patients were submitted to radiotherapy for choroid metastases of mammary carcinoma. Bilateral manifestation was found in three cases, thus sixteen eyes have been treated. All irradiations were performed with high voltage equipment. The posterior section of the eye was irradiated with 25 to 50 Gy over 2.5 to 5 weeks. Complete regression was achieved in nine out of sixteen cases, five patients showed an improvement of at least 50%, no considerable effect was found in two cases. The survival is 4 to 48 months (median survival 20 months) from the beginning of radiotherapy. Radiotherapy is a quick, efficient, and sparing treatment in choroid metastases. If applied in due time, it can prevent a visual disorder or amaurosis, thus improving the patients' quality of life.

  2. Growth Laws in Cancer: Implications for Radiotherapy

    CERN Document Server

    Castorina, P; Gabriele, P; Guiot, C

    2006-01-01

    Comparing both, the more conventional Gompertz tumor growth law (GL) and the ``Universal'' law (UL), recently proposed and applied to cancer,we have investigated the growth law's implications on various radiotherapy regimen. According to GL, the surviving tumor cell fraction could be reduced 'ad libidum', independently of the initial tumor mass,simply by increasing the number of treatments. On the contrary, if tumor growth dynamics would indeed follow the Universal scaling law, there is a lower limit of the survival fraction that cannot be reduced any further regardless of the total number of treatments. This finding can explain the so called ``tumor size effect'' and re-emphasizes the importance of early diagnosis as it implies that radiotherapy may be successful provided the tumor mass at treatment onset is rather small. Taken together with our previous works, implications of these findings include revisiting standard radiotherapy regimen and overall treatment protocols.

  3. Track structure modelling for ion radiotherapy

    CERN Document Server

    Korcyl, Marta

    2014-01-01

    In its broadest terms, doctoral dissertation entitled "Track structure modelling for ion radiotherapy" is part of the supporting research background in the development of the ambitious proton radiotherapy project currently under way at the Institute of Nuclear Physics PAN in Krak\\'ow. Another broad motivation was the desire to become directly involved in research on a topical and challenging subject of possibly developing a therapy planning system for carbon beam radiotherapy, based in its radiobiological part on the Track Structure model developed by prof. Robert Katz over 50 years ago. Thus, the general aim of this work was, firstly, to recapitulate the Track Structure model and to propose an updated and complete formulation of this model by incorporating advances made by several authors who had contributed to its development in the past. Secondly, the updated and amended (if necessary) formulation of the model was presented in a form applicable for use in computer codes which would constitute the "radiobio...

  4. Oral verrucous carcinoma. Treatment with radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Nair, M.K.; Sankaranarayanan, R.; Padmanabhan, T.K.; Madhu, C.S.

    1988-02-01

    Fifty-two cases of oral verrucous carcinoma treated with radiotherapy at the Regional Cancer Centre, Trivandrum, Kerala, India in 1982 were evaluated to determine the distribution within the oral cavity, clinical extent, and effectiveness of radiotherapy in controlling the disease. The most common site was the buccal mucosa. Fifty percent of the patients had clinically negative regional lymph nodes and 33% were in earlier stages (T1, T2, N0, and M0). The overall 3-year no evidence of disease (NED) survival rate was 44%. The 3-year NED survival rate with radium implant was 86%. We cannot comment on anaplastic transformation after radiotherapy because our treatment failures have not been subjected for biopsy concerning this matter. Because the results are comparable with those of well-differentiated squamous cell carcinoma, we think that the treatment policies advocated for oral squamous cell carcinoma are also applicable to oral verrucous carcinoma.

  5. Stereotactic Fractionated Radiotherapy in the Treatment of Juxtapapillary Choroidal Melanoma: The McGill University Experience

    Energy Technology Data Exchange (ETDEWEB)

    Al-Wassia, Rolina; Dal Pra, Alan; Shun, Kitty; Shaban, Ahmed [Department of Oncology, Division of Radiation Oncology, Montreal General Hospital, McGill University Health Centre, Montreal, Quebec (Canada); Corriveau, Christine [Department of Ophthalmology, Notre Dame Hospital, Centre Hospitalier de l' Universite de Montreal, Montreal, Quebec (Canada); Edelstein, Chaim; Deschenes, Jean [Department of Ophthalmology, McGill University Health Centre, Montreal, Quebec (Canada); Ruo, Russel; Patrocinio, Horacio [Department of Medical Physics, Montreal General Hospital, McGill University Health Centre, Montreal, Quebec (Canada); Cury, Fabio L.B. [Department of Oncology, Division of Radiation Oncology, Montreal General Hospital, McGill University Health Centre, Montreal, Quebec (Canada); DeBlois, Francois [Department of Medical Physics, Jewish General Hospital, McGill University, Montreal, Quebec (Canada); Shenouda, George, E-mail: george.shenouda@muhc.mcgill.ca [Department of Oncology, Division of Radiation Oncology, Montreal General Hospital, McGill University Health Centre, Montreal, Quebec (Canada)

    2011-11-15

    Purpose: To report our experience with linear accelerator-based stereotactic fractionated radiotherapy in the treatment of juxtapapillary choroidal melanoma. Methods and Materials: We performed a retrospective review of 50 consecutive patients diagnosed with juxtapapillary choroidal melanoma and treated with linear accelerator-based stereotactic fractionated radiotherapy between April 2003 and December 2009. Patients with small to medium sized lesions (Collaborative Ocular Melanoma Study classification) located within 2 mm of the optic disc were included. The prescribed radiation dose was 60 Gy in 10 fractions. The primary endpoints included local control, enucleation-free survival, and complication rates. Results: The median follow-up was 29 months (range, 1-77 months). There were 31 males and 29 females, with a median age of 69 years (range, 30-92 years). Eighty-four percent of the patients had medium sized lesions, and 16% of patients had small sized lesions. There were four cases of local progression (8%) and three enucleations (6%). Actuarial local control rates at 2 and 5 years were 93% and 86%, respectively. Actuarial enucleation-free survival rates at 2 and 5 years were 94% and 84%, respectively. Actuarial complication rates at 2 and 5 years were 33% and 88%, respectively, for radiation-induced retinopathy; 9.3% and 46.9%, respectively, for dry eye; 12% and 53%, respectively, for cataract; 30% and 90%, respectively, for visual loss [Snellen acuity (decimal equivalent), <0.1]; 11% and 54%, respectively, for optic neuropathy; and 18% and 38%, respectively, for neovascular glaucoma. Conclusions: Linear accelerator-based stereotactic fractionated radiotherapy using 60 Gy in 10 fractions is safe and has an acceptable toxicity profile. It has been shown to be an effective noninvasive treatment for juxtapapillary choroidal melanomas.

  6. Prevention and treatment of the orofacial complications of radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Rothwell, B.R.

    1987-03-01

    Radiotherapy of malignant head and neck tumors often causes extensive, permanent changes in salivary glands, peridental alveolar bone, and mucosal structures. Dental neglect and inappropriate dental management can cause complications. The potential orofacial side effects of radiotherapy are reviewed, as are preventive strategies for the dental treatment of patients scheduled to undergo radiotherapy.

  7. Radiotherapy in the management of Graves` ophthalmopathy

    Energy Technology Data Exchange (ETDEWEB)

    Sakata, Koh-ichi; Hareyama, Masato; Oouchi, Atsushi; Shidou, Mitsuo; Nagakura, Hisayasu; Morita, Kazuo; Osanai, Hajime; Ohtsuka, Kenji; Hinoda, Yuji [Sapporo Medical Univ. (Japan). School of Medicine

    1998-06-01

    To report the results of radiotherapy for patients with failure, adverse reactions or relative contraindications to the use of steroids or immunosuppressants, by using newly developed quantitative indexes. Fourteen female and six male patients with Graves` ophthalmopathy were treated with radiotherapy between 1989 and 1996. Prior to radiotherapy, eight patients received treatment with prednisone, four received immunosuppressants and four received a combination of both. Four patients with contraindications to steroids were initially managed with radiotherapy. Most of the patients received a dose of 24-28 Gy in 2 Gy fractions. We used the newly developed motility limitation index to assess extraocular motility. Treatment was well tolerated. There have been no late complications. All 12 patients with soft tissue signs such as edema, irritation, tearing and pain were improved. Proptosis did not improve or improved only slightly, 3 mm at best. However, proptosis in all but two has been stabilized and has not deteriorated in the follow-up period. Most of the patients have experienced an improvement of eye-muscle motility. Extraocular muscles that work for elevation were impaired more severely than the other muscles and this tended to remain. Of the 16 patients using steroids before or when radiotherapy was initiated, 15 were tapered off and only one patient required additional steroids, thus sparing the majority from steroid adverse reactions. Radiotherapy was effective in preventing exacerbations of active inflammatory ophthalmopathy in patients with Graves` disease with minimal morbidity and thus eliminated the adverse reactions associated with protracted corticosteroid use. The newly developed motility limitation index was useful in detecting delicate changes in motility of individual extraocular muscles. (author)

  8. Conformal radiotherapy of prostate carcinoma: Procedure description

    Directory of Open Access Journals (Sweden)

    Erak Marko

    2011-01-01

    Full Text Available Introduction. Today, three-dimensional conformal radiotherapy is a standard way in the radical treatment of localized prostate cancer, and it is an alternative to the radical prostatectomy. This method of radiotherapy treatment is widely accepted in the treatment of prostate cancer patients, and provides irradiation of targeted volume (prostate, seminal vesicles with dose escalation sparing the surrounding healthy tissues (rectum, bladder at the same time. That is not possible with the conventional twodimension technique. Procedure description. Three-dimensional conformal radiotherapy is a volumetric, visual simulation according to the computed tomography slices; it defines the tumour and organ at risk individually in each patient. Results of several studies have shown that there is a significant decrease in the development of acute toxicity when prostate cancer patients are treated with conformal radiotherapy. High dose irradiation gives excellent results in treatment of localized prostate carcinoma and improves treatment results in the patients with locally advanced carcinoma of prostate. Discussion. Prostate carcinoma irradiation techniques have been changed dramatically during recent years. Data obtained by computed tomography are important since the size and shapes of the prostate as well as its anatomic relations towards the rectum and bladder are considerably different in individual patients. The three-dimension plan of irradiation can be designed for each patient individually by performing computed tomography technique when planning radiotherapy. Conclusion. The advanced planning systems for conformal radiotherapy can reconstruct the anatomic structures of pelvis in three-dimension technique on the basis of computed tomography scans, which provides better conformality between the irradiation beam and geometrical shape of the tumour with minimal irradiation of the surrounding healthy tissue.

  9. Pelvic radiotherapy and sexual function in women

    Science.gov (United States)

    Froeding, Ligita Paskeviciute

    2015-01-01

    Background During the past decade there has been considerable progress in developing new radiation methods for cancer treatment. Pelvic radiotherapy constitutes the primary or (neo) adjuvant treatment of many pelvic cancers e.g., locally advanced cervical and rectal cancer. There is an increasing focus on late effects and an increasing awareness that patient reported outcomes (PROs) i.e., patient assessment of physical, social, psychological, and sexual functioning provides the most valid information on the effects of cancer treatment. Following cure of cancer allow survivors focus on quality of life (QOL) issues; sexual functioning has proved to be one of the most important aspects of concern in long-term survivors. Methods An updated literature search in PubMed was performed on pelvic radiotherapy and female sexual functioning/dysfunction. Studies on gynaecological, urological and gastrointestinal cancers were included. The focus was on the period from 2010 to 2014, on studies using PROs, on potential randomized controlled trials (RCTs) where female sexual dysfunction (FSD) at least constituted a secondary outcome, and on studies reporting from modern radiotherapy modalities. Results The literature search revealed a few RCTs with FSD evaluated as a PRO and being a secondary outcome measure in endometrial and in rectal cancer patients. Very limited information could be extracted regarding FSD in bladder, vulva, and anal cancer patients. The literature before and after 2010 confirms that pelvic radiotherapy, independent on modality, increases the risk significantly for FSD both compared to data from age-matched healthy control women and compared to data on patients treated by surgery only. There was only very limited data available on modern radiotherapy modalities. These are awaited during the next five years. Several newer studies confirm that health care professionals are still reluctant to discuss treatment induced sexual dysfunction with patients. Conclusions

  10. Radiotherapy in the management of aggressive fibromatosis

    Energy Technology Data Exchange (ETDEWEB)

    Atahan, I.L.; Akyol, F.; Zorlu, F.; Guerkaynak, M. (Hacettepe University Hospital, Ankara (Turkey). Dept. of Radiology)

    1989-09-01

    Four case reports are summarised concerning the management of aggressive fibromatosis in children and adolescents up to the age of 15. It was concluded that radiotherapy should be reserved for recurrences or inoperable cases. A dose of 5000-6000 cGy in 25-30 fractions depending on age of patient, site, and size of tumour is necessary, since most surgical recurrences appear in 12 months, all cases with positive surgical margins should receive doses in the range 4000-4500 cGy for microscopic disease. Radiotherapy-chemotherapy combinations can also be used. (UK).

  11. Radiotherapy versus combined modality in early stages

    DEFF Research Database (Denmark)

    Specht, L; Carde, P; Mauch, P;

    1992-01-01

    In early stage Hodgkin's disease the optimal choice of treatment for the individual patient is still an unresolved issue. So far, twenty-two randomized trials of radiotherapy alone versus radiotherapy plus combination chemotherapy have been carried out worldwide. The preliminary results of a global...... be kept at a minimum. Recently, trials have been carried out testing chemotherapy alone. The results of these trials are however conflicting. In order not to jeopardize the good results achieved with the standard treatments developed over the last three decades, newer treatment approaches should...... be carefully tested in large randomized trials before being implemented for general clinical use....

  12. Second Study of Hyper-Fractionated Radiotherapy

    Directory of Open Access Journals (Sweden)

    R. Jacob

    1999-01-01

    Full Text Available Purpose and Method. Hyper-fractionated radiotherapy for treatment of soft tissue sarcomas is designed to deliver a higher total dose of radiation without an increase in late normal tissue damage. In a previous study at the Royal Marsden Hospital, a total dose of 75 Gy using twice daily 1.25 Gy fractions resulted in a higher incidence of late damage than conventional radiotherapy using 2 Gy daily fractions treating to a total of 60 Gy. The current trial therefore used a lower dose per fraction of 1.2 Gy and lower total dose of 72 Gy, with 60 fractions given over a period of 6 weeks.

  13. Halo ring supporting the Brown-Roberts-Wells stereotactic frame for fractionated radiotherapy.

    Science.gov (United States)

    Carini, S; Scielzo, G; Grillo Ruggieri, F; Bistolfi, F; Ravegnani, M; Andreussi, L

    1994-01-01

    The authors describe a new instrumentation for repositioning of the Brown-Roberts-Wells (BRW) stereotaxic system, useful for precise fractionated radiotherapy. A lucite ring is fixed to the patient's skull with four screws. Another ring, partially open, is then firmly connected co-axially to the lower part of the first one with four spacer-bars. The fixture permits an exact repositioning of the B.R.W. stereotaxic system, placing the target point in the linear accelerator isocenter. The preliminary technical results obtained in five children are reported and the fixture performance, advantages, and perspectives are discussed.

  14. Perspex in the verification routines for accelerator beam; El Perspex en las rutinas de verificacion del haz en un acelerador

    Energy Technology Data Exchange (ETDEWEB)

    Paredes G, L.; Genis S, R. [Instituto Nacional de Investigaciones Nucleares, Apdo. Postal 18-1027, 11801 Mexico D.F. (Mexico)

    1998-12-31

    It is analyzed the use of a perspex solid phantom, adequately referred to a water phantom, as an auxiliary alternative for the daily stability verification routines or constance of radiation beam, as an option in the case of radiotherapy installations with high charge of accelerator working and with basic dosimetry equipment. (Author)

  15. Radiotherapy-induced emesis. An overview

    Energy Technology Data Exchange (ETDEWEB)

    Feyer, P.; Buchali, A.; Hinkelbein, M.; Budach, V. [Department Radiotherapy, Humboldt-University Berlin (Germany); Zimmermann, J.S. [Department Radiotherapy, Christian Albrechts-University Kiel (Germany); Titlbach, O.J. [Department of Medicine I, Hospital Friedrichshain, Berlin (Germany)

    1998-11-01

    Background: A significant number of patients receiving radiotherapy experience the distressing side effects of emesis and nausea. These symptoms are some of the most distressing problems for the patients influencing their quality of life. Methods: International study results concerning radiotherapy-induced emesis are demonstrated. A German multicenter questionnaire examining the strategies to prevent or to treat radiotherapy-induced nausea and emesis is presented. An international analysis concerning incidence of emesis and nausea in fractionated radiotherapy patients is discussed. Finally the consensus of the consensus conference on antiemetic therapy from the Perugia International Cancer Conference V is introduced. Results: Untreated emesis can lead to complications like electrolyte disorders, dehydration, metabolic disturbances and nutrition problems with weight loss. Prophylactic antiemetics are often given to patients receiving single high-dose radiotherapy to the abdomen. A survey has revealed that antiemetic prophylaxis is not routinely offered to the patients receiving fractionated radiotherapy. However, there is a need for an effective treatment of emesis for use in this group of patients, too. In 20% of patients nausea and emesis can cause a treatment interruption because of an inadequate control of symptoms. Like in chemotherapy strategies there exist high, moderate, and low emetogenic treatment regimens in radiotherapy as well. The most emetogenic potential has the total body irradiation followed by radiotherapy to the abdomen. Radiotherapy induced emesis can be treated effectively with conventional antiemetics up to 50%. Conclusions: Studies with total body irradiation, fractionated treatment and high-dose single exposures have cleary demonstrated the value of 5-HT3-receptor antagonist antiemetics. There is a response between 60 and 97%. There is no difference in the efficacy of the different 5-HT3-antagonists. High-risk patients should be prophylactic

  16. Asia honours accelerator physicists

    CERN Multimedia

    2010-01-01

    "Steve Meyers of Cern and Jie Wei of Beijing's Tsinghua University are the first recipients of a new prize for particle physics. The pair were honoured for their contributions to numerous particle-accelerator projects - including Cern's Large Hadron Collider - by the Asian Committee for Future Accelerators (ACFA)..." (1 paragraph)

  17. COLLECTIVE-FIELD ACCELERATION

    Energy Technology Data Exchange (ETDEWEB)

    Sessler, Andrew M.

    1969-07-04

    Diverse methods proposed for the acceleration of particles by means of collective fields are reviewed. A survey is made of the various currently active experimental programs devoted to investigating collective acceleration, and the present status of the research is briefly noted.

  18. Accelerators Beyond The Tevatron?

    Energy Technology Data Exchange (ETDEWEB)

    Lach, Joseph; /Fermilab

    2010-07-01

    Following the successful operation of the Fermilab superconducting accelerator three new higher energy accelerators were planned. They were the UNK in the Soviet Union, the LHC in Europe, and the SSC in the United States. All were expected to start producing physics about 1995. They did not. Why?

  19. KEK digital accelerator

    Science.gov (United States)

    Iwashita, T.; Adachi, T.; Takayama, K.; Leo, K. W.; Arai, T.; Arakida, Y.; Hashimoto, M.; Kadokura, E.; Kawai, M.; Kawakubo, T.; Kubo, Tomio; Koyama, K.; Nakanishi, H.; Okazaki, K.; Okamura, K.; Someya, H.; Takagi, A.; Tokuchi, A.; Wake, M.

    2011-07-01

    The High Energy Accelerator Research Organization KEK digital accelerator (KEK-DA) is a renovation of the KEK 500 MeV booster proton synchrotron, which was shut down in 2006. The existing 40 MeV drift tube linac and rf cavities have been replaced by an electron cyclotron resonance (ECR) ion source embedded in a 200 kV high-voltage terminal and induction acceleration cells, respectively. A DA is, in principle, capable of accelerating any species of ion in all possible charge states. The KEK-DA is characterized by specific accelerator components such as a permanent magnet X-band ECR ion source, a low-energy transport line, an electrostatic injection kicker, an extraction septum magnet operated in air, combined-function main magnets, and an induction acceleration system. The induction acceleration method, integrating modern pulse power technology and state-of-art digital control, is crucial for the rapid-cycle KEK-DA. The key issues of beam dynamics associated with low-energy injection of heavy ions are beam loss caused by electron capture and stripping as results of the interaction with residual gas molecules and the closed orbit distortion resulting from relatively high remanent fields in the bending magnets. Attractive applications of this accelerator in materials and biological sciences are discussed.

  20. KEK digital accelerator

    Directory of Open Access Journals (Sweden)

    T. Iwashita

    2011-07-01

    Full Text Available The High Energy Accelerator Research Organization KEK digital accelerator (KEK-DA is a renovation of the KEK 500 MeV booster proton synchrotron, which was shut down in 2006. The existing 40 MeV drift tube linac and rf cavities have been replaced by an electron cyclotron resonance (ECR ion source embedded in a 200 kV high-voltage terminal and induction acceleration cells, respectively. A DA is, in principle, capable of accelerating any species of ion in all possible charge states. The KEK-DA is characterized by specific accelerator components such as a permanent magnet X-band ECR ion source, a low-energy transport line, an electrostatic injection kicker, an extraction septum magnet operated in air, combined-function main magnets, and an induction acceleration system. The induction acceleration method, integrating modern pulse power technology and state-of-art digital control, is crucial for the rapid-cycle KEK-DA. The key issues of beam dynamics associated with low-energy injection of heavy ions are beam loss caused by electron capture and stripping as results of the interaction with residual gas molecules and the closed orbit distortion resulting from relatively high remanent fields in the bending magnets. Attractive applications of this accelerator in materials and biological sciences are discussed.

  1. Accelerators, Beams And Physical Review Special Topics - Accelerators And Beams

    Energy Technology Data Exchange (ETDEWEB)

    Siemann, R.H.; /SLAC

    2011-10-24

    Accelerator science and technology have evolved as accelerators became larger and important to a broad range of science. Physical Review Special Topics - Accelerators and Beams was established to serve the accelerator community as a timely, widely circulated, international journal covering the full breadth of accelerators and beams. The history of the journal and the innovations associated with it are reviewed.

  2. The Accelerated Kepler Problem

    CERN Document Server

    Namouni, Fathi

    2007-01-01

    The accelerated Kepler problem is obtained by adding a constant acceleration to the classical two-body Kepler problem. This setting models the dynamics of a jet-sustaining accretion disk and its content of forming planets as the disk loses linear momentum through the asymmetric jet-counterjet system it powers. The dynamics of the accelerated Kepler problem is analyzed using physical as well as parabolic coordinates. The latter naturally separate the problem's Hamiltonian into two unidimensional Hamiltonians. In particular, we identify the origin of the secular resonance in the accelerated Kepler problem and determine analytically the radius of stability boundary of initially circular orbits that are of particular interest to the problem of radial migration in binary systems as well as to the truncation of accretion disks through stellar jet acceleration.

  3. On Accelerated Black Holes

    CERN Document Server

    Letelier, P S; Letelier, Patricio S.; Oliveira, Samuel R.

    1998-01-01

    The C-metric is revisited and global interpretation of some associated spacetimes are studied in some detail. Specially those with two event horizons, one for the black hole and another for the acceleration. We found that the spacetime fo an accelerated Schwarzschild black hole is plagued by either conical singularities or lack of smoothness and compactness of the black hole horizon. By using standard black hole thermodynamics we show that accelerated black holes have higher Hawking temperature than Unruh temperature. We also show that the usual upper bound on the product of the mass and acceleration parameters (<1/sqrt(27)) is just a coordinate artifact. The main results are extended to accelerated Kerr black holes. We found that they are not changed by the black hole rotation.

  4. The evaluation of neutron and gamma ray dose equivalent distributions in patients and the effectiveness of shield materials for high energy photons radiotherapy facilities.

    Science.gov (United States)

    Ghassoun, J; Senhou, N

    2012-04-01

    In this study, the MCNP5 code was used to model radiotherapy room of a medical linear accelerator operating at 18 MV and to evaluate the neutron and the secondary gamma ray fluences, the energy spectra and the dose equivalent distributions inside a liquid tissue-equivalent (TE) phantom. The obtained results were compared with measured data published in the literature. Moreover, the shielding effects of various neutron material shields on the radiotherapy room wall were also investigated. Our simulation results showed that paraffin wax containing boron carbide presents enough effectiveness to reduce both neutron and secondary gamma ray doses.

  5. Grounded theory for radiotherapy practitioners: Informing clinical practice

    Energy Technology Data Exchange (ETDEWEB)

    Walsh, N.A., E-mail: Nadia.Walsh@gstt.nhs.u [Medical Physics Department, Guy' s and St Thomas' NHS Foundation Trust, St Thomas' Hospital, London SE1 7EH (United Kingdom)

    2010-08-15

    Radiotherapy practitioners may be best placed to undertake qualitative research within the context of cancer, due to specialist knowledge of radiation treatment and sensitivity to radiotherapy patient's needs. The grounded theory approach to data collection and analysis is a unique method of identifying a theory directly based on data collected within a clinical context. Research for radiotherapy practitioners is integral to role expansion within the government's directive for evidence-based practice. Due to the paucity of information on qualitative research undertaken by radiotherapy radiographers, this article aims to assess the potential impact of qualitative research on radiotherapy patient and service outcomes.

  6. Advancements in radiotherapy for lung cancer in China

    Institute of Scientific and Technical Information of China (English)

    Lujun Zhao; Luhua Wang

    2015-01-01

    Lung cancer is the leading cause of death due to cancer in China. In recent years, great progress has been made in radiotherapy for lung cancer patients in China. The main advance-ments include the fol owing aspects:(1) stereotactic ablative radiotherapy for early stage non-smal cel lung cancer (NSCLC), (2) post-operative radiotherapy for NSCLC, (3) combined chemotherapy and radiotherapy for local y advanced NSCLC, (4) improved radiotherapy for advanced NSCLC, and 5) prediction of radiation-induced lung toxicity.

  7. Radiotherapy in the management of early breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Wei [Westmead Breast Cancer Institute, Westmead Hospital, Westmead, New South Wales (Australia); Department of Radiation Oncology, Westmead Hospital, New South Wales (Australia)

    2013-03-15

    Radiotherapy is an indispensible part of the management of all stages of breast cancer. In this article, the common indications for radiotherapy in the management of early breast cancer (stages 0, I, and II) are reviewed, including whole-breast radiotherapy as part of breast-conserving treatment for early invasive breast cancer and pre-invasive disease of ductal carcinoma in situ, post-mastectomy radiotherapy, locoregional radiotherapy, and partial breast irradiation. Key clinical studies that underpin our current practice are discussed briefly.

  8. Treatment results of radical radiotherapy of carcinoma uterine cervix using external beam radiotherapy and high dose rate intracavitary radiotherapy

    Directory of Open Access Journals (Sweden)

    Azad S

    2010-01-01

    Full Text Available Aim: To report the outcome of carcinoma cervix patients treated radically by external beam radiotherapy and high dose rate intracavitary radiotherapy. Material and Methods: From January 2005 to December 2006, a total of 709 newly diagnosed cases of carcinoma cervix were reported in our department. All cases were staged according to the International Federation of Gynecologist and Oncologist staging system. Out of 709 cases, 342 completed radical radiotherapy and were retrospectively analyzed for the presence of local residual disease, local recurrence, distant metastases, radiation reaction, and disease free survival. Results: There were 11(3.22%, 82(23.98%, 232(67.83%, and 17(4.97% patients in stages I, II, III, and IV, respectively. The median follow up time for all patients was 36 months (range 3 -54 months. The overall treatment time (OTT ranged from 52 to 69 days (median 58 days. The 3 year disease free survival rate was 81.8%, 70.7%, 40.08%, and 11.76% for stages I, II, III, and IV, respectively. There were 91 (26.6% cases with local residual diseases, 27(7.9% developed distant metastasis, and 18(5.26% pts had local recurrence. Discussion: The results of this study suggest that radical radiotherapy with HDR brachytherapy was appropriate for the treatment of early staged cancer of uterine cervix. For locally advanced cancer of cervix addition of concurrent chemotherapy, higher radiation doses, reduction of overall treatment time to less than 8 weeks, and use of latest radiotherapy techniques such as IMRT is recommended to improve the results.

  9. Dosimetric comparison on tissue interfaces with TLD dosimeters, L-alanine, EDR2 films and Penelope simulation for a Co-60 source and linear accelerator in radiotherapy; Comparacion dosimetrica en interfaces de tejidos con dosimetros TLD, L-alanina, peliculas EDR2 y simulacion Penelope para una fuente de Co-60 y acelerador lineal en radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Vega R, J. L.; Cayllahua, F.; Apaza, D. G.; Javier, H., E-mail: josevegaramirez@yahoo.es [Universidad Nacional de San Agustin, Departamento de Fisica, Av. Independencia s/n, Arequipa (Peru)

    2015-10-15

    Percentage depth dose curves were obtained with TLD-100 dosimeters, EDR2 films and Penelope simulation at the interfaces in an inhomogeneous mannequin, composed by equivalent materials to the human body built for this study, consisting of cylindrical plates of solid water-bone-lung-bone-solid water of 15 cm in diameter and 1 cm in height; plates were placed in descending way (4-2-8-2-4). Irradiated with Co-60 source (Theratron Equinox-100) for small radiation fields 3 x 3 cm{sup 2} and 1 x 1 cm{sup 2} at a surface source distance of 100 cm from mannequin. The TLD-100 dosimeters were placed in the center of each plate of mannequin irradiated at 10 Gy. The results were compared between these measurement techniques, giving good agreement in interfaces better than 97%. This study was compared with the same characteristics of another study realized with other equivalent materials to human body not homogeneous acrylic-bone-cork-bone-acrylic. The percentage depth dose curves were obtained with mini-dosimeters L-alanine of 1 mm in diameter and 3 mm in height and 3.5 to 4.0 mg of mass with spectrometer band K (EPR). The mini-dosimeters were irradiated with a lineal accelerator PRIMUS Siemens 6 MV. The results of percentage depth dose of L-alanine mini-dosimeters show a good agreement with the percentage depth dose curves of Penelope code, better than 97.7% in interfaces of tissues. (Author)

  10. Prostate cancer radiotherapy in elderly person; Radiotherapie du cancer de la prostate chez la personne agee

    Energy Technology Data Exchange (ETDEWEB)

    Serre, A. [Centre Alexis-Vautrin, Nancy (France)

    2011-10-15

    The author discusses the issue of prostate cancer radiotherapy in the case of elderly persons. The choice of the therapeutic strategy (local, hormonotherapy, simple monitoring) is complex. Different aspects must be considered: the carcinologic situation assessment, the patient health condition, the patient life expectancy, and the possible side effects of treatment. Radiotherapy appears to be a major therapeutic asset, but dose levels, toxicity effects must then be considered. Short communication

  11. Results of heavy ion radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Castro, J.R. [Lawrence Berkeley Lab., CA (United States). Life Sciences Div.

    1994-04-01

    The potential of heavy ion therapy for clinical use in cancer therapy stems from the biological parameters of heavy charged particles, and their precise dose localization. Biologically, carbon, neon and other heavy ion beams (up to about silicon) are clinically useful in overcoming the radioresistance of hypoxic tumors, thus increasing biological effectiveness relative to low-LET x-ray or electron beams. Cells irradiated by heavy ions show less variation in cell-cycle related radiosensitivity and decreased repair of radiation injury. The physical parameters of these heavy charged particles allow precise delivery of high radiation doses to tumors while minimizing irradiation of normal tissues. Clinical use requires close interaction between radiation oncologists, medical physicists, accelerator physicists, engineers, computer scientists and radiation biologists.

  12. CSIR cyclotron modified for radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    National Accelerator Centre (NAC) staff members will be making an important contribution to radiation therapy in South Africa when the Transvaal Department of Hospital Services starts treating certain types of cancer with fast neutrons, at the Pretoria Cyclotron on the CSIR campus. The fast neutrons will be utilized mainly to treat advanced cancers of the head and the neck. The project will develop along two lines. Firstly the Pretoria cyclotron must be modified and secondly satisfactory radiobiological data must be provided before patients may be treated. This radiobiological experiment heralds a new area for use of the cyclotron which has thus far been used mainly for basic nuclear research and the production of isotopes.

  13. Barriers to palliative radiotherapy referral: A Canadian perspective

    Energy Technology Data Exchange (ETDEWEB)

    Samant, Rajiv S.; Fitzgibbon, Edward; Meng, Joanne; Graham, Ian D. [Univ. of Ottawa. Ottawa, ON (Canada)

    2007-07-15

    Radiotherapy is an effective but underutilized treatment modality for cancer patients. We decided to investigate the factors influencing radiotherapy referral among family physicians in our region. A 30-item survey was developed to determine palliative radiotherapy knowledge and factors influencing referral. It was sent to 400 physicians in eastern Ontario (Canada) and the completed surveys were evaluated. The overall response rate was 50% with almost all physicians seeing cancer patients recently (97%) and the majority (80%) providing palliative care. Approximately 56% had referred patients for radiotherapy previously and 59% were aware of the regional community oncology program. Factors influencing radiotherapy referral included the following: waiting times for radiotherapy consultation and treatment, uncertainty about the benefits of radiotherapy, patient age, and perceived patient inconvenience. Physicians who referred patients for radiotherapy were more than likely to provide palliative care, work outside of urban centres, have hospital privileges and had sought advice from a radiation oncologist in the past. A variety of factors influence the referral of cancer patients for radiotherapy by family physicians and addressing issues such as long waiting times, lack of palliative radiotherapy knowledge and awareness of Cancer Centre services could increase the rate of appropriate radiotherapy patient referral.

  14. Stereotactic body radiotherapy in prostate cancer: is rapidarc a better solution than cyberknife?

    Science.gov (United States)

    Macdougall, N D; Dean, C; Muirhead, R

    2014-01-01

    There is increasing interest in stereotactic body radiotherapy (SBRT) for the management of prostate adenocarcinoma, with encouraging initial biological progression-free survival results. However, the limited literature is dominated by the use of the Cyberknife platform. This led to an international phase III study comparing outcomes for Cyberknife SBRT with both surgery and conventionally fractionated intensity-modulated radiotherapy (the PACE study). We aim to compare Cyberknife delivery with Rapidarc, a more widely available treatment platform. The scans of six previous prostate radiotherapy patients with a range of prostate sizes were chosen. The clinical target volume was defined as the prostate gland, with 3 mm added for the Cyberknife planning target volume (PTV) and 5 mm for the Rapidarc PTV. Accuray multiplan v. 4.5 was used for planning with delivery on a Cyberknife VSI system v9.5; Varian Eclipse v10 was used for Rapidarc planning with delivery using a Varian 21EX linear accelerator. Both systems attempted to deliver at least 35 Gy to the PTV in five fractions with PTV heterogeneity delivery time was in favour of Rapidarc. We have shown that there is no discernible dosimetric advantage to choosing Cyberknife over Rapidarc for SBRT delivery in prostate cancer. Given the significant benefits of Rapidarc in terms of availability, planning and delivery time, the authors suggest that phase III trials of SBRT should include Rapidarc or equivalent rotational delivery platforms. Copyright © 2013 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  15. Optimizing the TLD-100 readout system for various radiotherapy beam doses using the Taguchi methodology

    Energy Technology Data Exchange (ETDEWEB)

    Chen, C.Y. [School of Medical Imaging Technology, Chung Shan Medical University, Taichung 402, Taiwan (China); Liu, K.C.; Chen, H.H. [Graduate Institute of Radiological Science, Central Taiwan University of Science and Technology, Takun, Taichung 406, Taiwan (China); Pan, L.K. [Graduate Institute of Radiological Science, Central Taiwan University of Science and Technology, Takun, Taichung 406, Taiwan (China)], E-mail: lkpan@ctust.edu.tw

    2010-03-15

    The TLD-100 readout system was optimized for various radiotherapy beam doses using the Taguchi method. The radiotherapy beam was produced by a Varian 21EX linear accelerator (LINAC) at 6 MV. The beam doses were 50, 100 and 150 cGy, and the measured data in each group were averaged from three TLD-100 chips. A total of nine combinations of four parameters were arranged, in the manner suggested by Taguchi. The four parameters were defined as initial temperature, heating rate, preheat time and maximum set temperature of the readout system during TLD reading. The loss function {eta} adopted herein was specifically defined to satisfy the requirements of both sharp linearity and good reproducibility of the TLD reading at various radiotherapy beam doses. The optimized values were: (1) 50 deg. C for initial temperature, (2) 3 deg. C/s for heating rate, (3) 5 min for the TLD preheat time and (4) 250 deg. C for the maximum temperature for TLD reading. Additionally, the parameters that dominated the TLD readout were: (1) initial temperature, (2) heating rate and (4) maximum temperature setting for TLD reading; and the minor parameter was (3) TLD preheat time before reading. The interactions among the dominant parameters were also studied: no significant cross interaction occurred between initial temperature and heating rate or between initial temperature and maximum temperature. However, a complex cross-interaction existed between optimal heating rate and maximum temperature.

  16. Intraoperative Radiotherapy for Breast Cancer: The Lasting Effects of a Fleeting Treatment

    Directory of Open Access Journals (Sweden)

    Harriet B. Eldredge-Hindy

    2014-01-01

    Full Text Available In well-selected patients who choose to pursue breast conservation therapy (BCT for early-stage breast cancer, partial breast irradiation (PBI delivered externally or intraoperatively, may be a viable alternative to conventional whole breast irradiation. Two large, contemporary randomized trials have demonstrated breast intraoperative radiotherapy (IORT to be noninferior to whole breast external beam radiotherapy (EBRT when assessing for ipsilateral breast tumor recurrence in select patients. Additionally, IORT and other PBI techniques are likely to be more widely adopted in the future because they improve patient convenience by offering an accelerated course of treatment. Coupled with these novel techniques for breast radiotherapy (RT are distinct toxicity profiles and unique cosmetic alterations that differ from conventional breast EBRT and have the potential to impact disease surveillance and patient satisfaction. This paper will review the level-one evidence for treatment efficacy as well as important secondary endpoints like RT toxicity, breast cosmesis, quality of life, patient satisfaction, and surveillance mammography following BCT with IORT.

  17. Respiratory monitoring with an acceleration sensor

    Energy Technology Data Exchange (ETDEWEB)

    Ono, Tomohiro; Takegawa, Hideki; Ageishi, Tatsuya; Takashina, Masaaki; Numasaki, Hodaka; Matsumoto, Masao; Teshima, Teruki, E-mail: teshima@sahs.med.osaka-u.ac.jp [Department of Medical Physics and Engineering, Osaka University Graduate School of Medicine, Yamadaoka 1-7, Suita-shi, Osaka 565-0871 (Japan)

    2011-10-07

    Respiratory gating radiotherapy is used to irradiate a local area and to reduce normal tissue toxicity. There are certain methods for the detection of tumor motions, for example, using internal markers or an external respiration signal. However, because some of these respiratory monitoring systems require special or expensive equipment, respiratory monitoring can usually be performed only in limited facilities. In this study, the feasibility of using an acceleration sensor for respiratory monitoring was evaluated. The respiratory motion was represented by means of a platform and measured five times with the iPod touch (registered) at 3, 4 and 5 s periods of five breathing cycles. For these three periods of the reference waveform, the absolute means {+-} standard deviation (SD) of displacement were 0.45 {+-} 0.34 mm, 0.33 {+-} 0.24 mm and 0.31 {+-} 0.23 mm, respectively. On the other hand, the corresponding absolute means {+-} SD for the periods were 0.04 {+-} 0.09 s, 0.04 {+-} 0.02 s and 0.06 {+-} 0.04 s. The accuracy of respiratory monitoring using the acceleration sensor was satisfactory in terms of the absolute means {+-} SD. Using the iPod touch (registered) for respiratory monitoring does not need special equipment and makes respiratory monitoring easier. For these reasons, this system is a viable alternative to other respiratory monitoring systems.

  18. Sorafenib and radiotherapy association for hepatocellular carcinoma; Sorafenib et radiotherapie dans le carcinome hepatocellulaire

    Energy Technology Data Exchange (ETDEWEB)

    Girard, N. [Service de pneumologie, hopital Louis-Pradel, hospices Civils de Lyon, 28, avenue du Doyen-Jean-Lepine, 69500 Bron (France); UMR 754, universite Claude-Bernard Lyon 1, 43, boulevard du 11-novembre-1918, 69622 Villeurbanne cedex (France); Mornex, F. [UMR 754, universite Claude-Bernard Lyon 1, 43, boulevard du 11-novembre-1918, 69622 Villeurbanne cedex (France); Departement de radiotherapie-oncologie, centre hospitalier Lyon Sud, 165, chemin du Grand-Revoyet, 69495 Pierre-Benite cedex (France)

    2011-02-15

    Conformal radiotherapy is a promising therapeutic strategy for hepatocellular carcinoma (HCC), producing local control rates above 90% within the radiation beam. However, survival after radiotherapy remains limited by the high frequency of intra- and extra-hepatic recurrences, which occurs in 40-50 and 20-30% of cases, respectively. Sorafenib (BAY43-9006, Nexavar; Bayer, West Haven, CT) is a small molecule inhibitor that demonstrated potent activity to target v-raf murine sarcoma oncogene homologue B1 (BRAF) and VEGFR tyrosine kinases. Sorafenib is the only drug that demonstrated effectiveness to increase overall survival in advanced or metastatic hepatocellular carcinoma. The rationale to combine radiotherapy with sorafenib is the following: (1) targeting RAS-RAF-MAPK and VEGFR signaling pathways, which are specifically activated after exposure to radiation, and responsible for radio-resistance phenomenon; (2) enhancing the oxygen effect through normalization of the surviving tumor vasculature; and (3) synchronization of the cell cycle. Sorafenib and radiotherapy represent complementary strategies, as radiotherapy may be useful to prolong the effect of sorafenib through control of the macroscopic disease, when sorafenib may target latent microscopic disease. Sorafenib and radiotherapy associations are thus based on a relevant biological and clinical rationale and are being evaluated in ongoing phase I-II trials. (authors)

  19. Radiotherapy for inverted papilloma: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Levendag, P.C.; Annyas, A.A.; Escajadillo, J.R.; Elema, J.D. (Rijksuniversiteit Groningen (Netherlands). Academisch Ziekenhuis)

    1984-06-01

    Inverted papilloma is an infrequent tumour of the nasal cavity and paranasal sinuses associated with controversy. The incidence of carcinoma in situ associated with inverted papilloma, has not been very well documented until now. Therefore the authors present a case report characterized by an aggressive clinical behaviour, treated by extensive surgery and ultimately controlled by radiotherapy.

  20. Radiotherapy for inverted papilloma: a case report.

    Science.gov (United States)

    Levendag, P C; Annyas, A A; Escajadillo, J R; Elema, J D

    1984-06-01

    Inverted papilloma is an infrequent tumour of the nasal cavity and paranasal sinuses associated with controversy. The incidence of carcinoma in situ associated with inverted papilloma, has not been very well documented until now. Therefore, we present a case report characterized by an aggressive clinical behaviour, treated by extensive surgery and ultimately controlled by radiotherapy.

  1. Towards online MRI-guided radiotherapy

    NARCIS (Netherlands)

    Bol, G.H.

    2015-01-01

    First, we present two offline position verification methods which can be used in radiotherapy for detecting the position of the bony anatomy of a patient automatically with portal imaging, even if every single portal image of each segment of an (IMRT) treatment beam contains insufficient matching in

  2. Effects of radiotherapy on bone tissue

    Energy Technology Data Exchange (ETDEWEB)

    Cunha, Samantha Seara da; Almeida, Darcy de [Universidade Federal da Paraiba (UFPB), Joao Pessoa, PB (Brazil)]. E-mail: samanthaseara@hotmail.com; Sarmento, Viviane Almeida; Ramalho, Luciana Maria Pedreira; Freitas, Andre Carlos de [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil). Faculdade de Odontologia; Tavares, Maria Eulina; Souza, Jailton Caetano [Hospital Santa Izabel (HSI), Salvador, BA (Brazil); Veeck, Elaine Bauer; Costa, Nilza Pereira da [Pontificia Univ. Catolica do Rio Grande do Sul (PUCRS), Porto Alegre, RS (Brazil)

    2007-05-15

    Objective: To investigate the effects of radiotherapy on bone tissues and the accuracy of gray level measurements on radiographic images. Materials and methods: Four Wistar rats were submitted to external radiotherapy (single 3000 cGy dose) on an area of 2 cm x 2 cm of their right legs. The animals were sacrificed six weeks after radiotherapy, and both irradiated and contralateral (non-irradiated) legs were removed, dissected, evaluated for thickness, x-rayed in a standardized form and histologically processed (stained with hematoxylin-eosin and picrosirius red). The radiographs were digitalized and the gray level average was measured with the ImageTool{sup R} software. Results: The femur thickness of non-irradiated legs was greater than that of the irradiated legs (p < 0.05). Radiographically, the findings indicated a higher bone density in the non-irradiated legs, although with no statistically significant difference (p > 0.05). Histological analysis of the irradiated legs demonstrated a decrease in the number of osteocytes and Haversian canals, although with no statistically significance (p > 0.05). On the other hand, a significant increase in adipocytes was observed, resulting in a reduction of medullary tissue in the irradiated legs (p < 0.05), besides a higher osteoblastic activity in the non-irradiated legs (p < 0.05). Conclusion: Radiotherapy within the above mentioned parameters determined a decrease in activity of bone remodeling, which could be radiographically detected in the majority of the evaluated specimens. (author)

  3. The Role of Radiotherapy in Acromegaly.

    Science.gov (United States)

    Hannon, Mark J; Barkan, Ariel L; Drake, William M

    2016-01-01

    Radiotherapy has, historically, played a central role in the management of acromegaly, and the last 30 years have seen substantial improvements in the technology used in the delivery of radiation therapy. More recently, the introduction of highly targeted radiotherapy, or 'radiosurgery', has further increased the therapeutic options available in the management of secretory pituitary tumors. Despite these developments, improvements in primary surgical outcomes, an increase in the range and effectiveness of medical therapy options, and long-term safety concerns have combined to dictate that, although still deployed in selected cases, the use of radiotherapy in the management of acromegaly has declined steadily over the past 2 decades. In this article, we review some of the main studies that have documented the efficacy of pituitary radiotherapy on growth hormone hypersecretion and summarize the data around its potential deleterious effects, including hypopituitarism, cranial nerve damage, and the development of radiation-related intracerebral tumors. We also give practical recommendations to guide its future use in patients with acromegaly, generally, as a third-line intervention after neurosurgical intervention in combination with various medical therapy options.

  4. INDICATIONS FOR RADIOTHERAPY AFTER NECK DISSECTION

    NARCIS (Netherlands)

    Strojan, Primoz; Ferlito, Alfio; Langendijk, Johannes A.; Silver, Carl E.

    Up-front surgery and postoperative radiotherapy constitute a well-recognized treatment concept for locally or regionally advanced squamous cell carcinoma of the head and neck. This "treatment package" is further intensified with the concomitant application of chemotherapy during irradiation when

  5. Three dimensional conformal postoperative radiotherapy for ...

    African Journals Online (AJOL)

    Azza Helal

    2013-06-17

    Jun 17, 2013 ... showed the best dose homogeneity and conformity and lowest max dose to PTV and to the ... nique, size of treatment field, total dose and dose/fraction.6,7 ..... Cooperative Group: the role of radiotherapy in the treatment of.

  6. Oral sequelae of head and neck radiotherapy

    NARCIS (Netherlands)

    Vissink, A; Jansma, J; Spijkervet, FKL; Burlage, FR; Coppes, RP

    In addition to anti-tumor effects, ionizing radiation causes damage in normal tissues located in the radiation portals. Oral complications of radiotherapy in the head and neck region are the result of the deleterious effects of radiation on, e. g., salivary glands, oral mucosa, bone, dentition,

  7. [Hopes of high dose-rate radiotherapy].

    Science.gov (United States)

    Fouillade, Charles; Favaudon, Vincent; Vozenin, Marie-Catherine; Romeo, Paul-Henri; Bourhis, Jean; Verrelle, Pierre; Devauchelle, Patrick; Patriarca, Annalisa; Heinrich, Sophie; Mazal, Alejandro; Dutreix, Marie

    2017-04-01

    In this review, we present the synthesis of the newly acquired knowledge concerning high dose-rate irradiations and the hopes that these new radiotherapy modalities give rise to. The results were presented at a recent symposium on the subject. Copyright © 2017. Published by Elsevier Masson SAS.

  8. Magnetic resonance imaging in radiotherapy treatment planning

    NARCIS (Netherlands)

    Moerland, Marinus Adriaan

    2001-01-01

    From its inception in the early 1970's up to the present, magnetic resonance imaging (MRI) has evolved into a sophisticated technique, which has aroused considerable interest in var- ious subelds of medicine including radiotherapy. MRI is capable of imaging in any plane and does not use ionizing rad

  9. Tumour-host dynamics under radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Placeres Jimenez, Rolando, E-mail: rpjcu@yahoo.com [Departamento de Fi' sica, Universidade Federal de Sao Carlos, Sao Carlos - SP (Brazil); Ortiz Hernandez, Eloy [Centre of Medicine and Complexity, Medical University Carlos J. Finlay, Carretera Central s/n, Camagueey (Cuba)

    2011-09-15

    Highlight: > Tumour-host interaction is modelled by Lotka-Volterra equations. > A brief review of the motion integral and analysis of linear stability is presented. > Radiotherapy is introduced into the model, using a periodic Dirac delta function. > A two-dimensional logistic map is derived from the modified Lotka-Volterra model. > It is shown that tumour can be controlled by a correct selection of therapy strategy. - Abstract: Tumour-host interaction is modelled by the Lotka-Volterra equations. Qualitative analysis and simulations show that this model reproduces all known states of development for tumours. Radiotherapy effect is introduced into the model by means of the linear-quadratic model and the periodic Dirac delta function. The evolution of the system under the action of radiotherapy is simulated and parameter space is obtained, from which certain threshold of effectiveness values for the frequency and applied doses are derived. A two-dimensional logistic map is derived from the modified Lotka-Volterra model and used to simulate the effectiveness of radiotherapy in different regimens of tumour development. The results show the possibility of achieving a successful treatment in each individual case by employing the correct therapeutic strategy.

  10. Radical radiotherapy for urinary bladder cancer

    DEFF Research Database (Denmark)

    Fokdal, Lars; von der Maase, Hans; Høyer, Morten

    2006-01-01

    The exact value of radiotherapy in the treatment of muscle-invasive       bladder cancer is difficult to establish, as most studies exploring this       issue are retrospective with different procedures for selecting patients       for treatment, as well as varying treatment strategies. An estima...

  11. Department and patient management in radiotherapy. The Freiburg model; Abteilungs- und Patientenmanagement in der Strahlenheilkunde. Das Freiburger Modell

    Energy Technology Data Exchange (ETDEWEB)

    Heinemann, Felix; Frommhold, Hermann [Universitaetsklinik fuer Strahlenheilkunde, Freiburg (Germany). Funktionsbereich Klinische ud Administrative Informatik; Roehner, Fred; Bruggmoser, Gregor [Radiologische Universitaetsklinik, Freiburg (Germany). Funktionsbereich Medizinische Physik; Schmucker, Marianne; Henne, Karl; Grosu, Anca-Ligia [Radiologische Universitaetsklinik, Freiburg (Germany). Klinik fuer Strahlenheilkunde

    2009-03-15

    Background and Purpose: The activities in radiotherapy are mainly affected by numerous partly very complex operational procedures which have to be completed while high safety requirements have to be fulfilled. This fact and steadily increasing economic pressure are forcing us to develop new strategies which help us to optimize our operational procedures and assure their reliability. As there are not so many radiotherapeutic institutions and the main focus, up to now, was mainly stressed on the acceleration systems (radiation planning, acceleration control), only few industrial systems are available which could also support the economic, organizational and administrative needs of radiotherapy. Methods: During the building operations for the 'new clinic for radiotherapy' at the University Hospital Freiburg, Germany, the staff of the clinical and administrative information and the medical physicists developed, in close cooperation with the physicians, a comprehensive concept to control and organize a radiotherapeutic institution. This concept was examined during the construction phase of the new clinic and the adjoined HBFG ('Hochschulbaufoerderungsgesetz') process by the 'Deutsche Forschungsgemeinschaft' and financed totally by federal funds. Results and Conclusion: The precondition for the goal to operate a homogeneous and comprehensive management of a clinic for radiotherapy was the direct connection of the acceleration area with the organizational/administrative surrounding. The thus developed common basic dates and consistence created transparency and allowed us for the first time to control all operational procedures by EDV-technical means. After 2 years full-time operation and implementation of numerous particular projects we are now ready for film- and paperless digital work. (orig.)

  12. Radiotherapy of prostate cancer; Strahlentherapie des Prostatakarzinoms

    Energy Technology Data Exchange (ETDEWEB)

    Krause, S.; Herfarth, K. [Universitaetsklinikum Heidelberg, Klinik fuer Radioonkologie und Strahlentherapie, Heidelberg (Germany)

    2011-11-15

    With the development of modern radiation techniques, such as intensity-modulated radiotherapy (IMRT), a dose escalation in the definitive radiotherapy of prostate cancer and a consecutive improvement in biochemical recurrence-free survival (BFS) could be achieved. Among others, investigators at the Memorial Sloan-Kettering Cancer Center (MSKCC) saw 5-year BFS rates of up to 98%. A further gain in effectiveness and safety is expected of hypofractionation schedules, as suggested by data published by Kupelian et al., who saw a low 5-year rate of grade {>=}2 rectal side-effects of 4.5%. However, randomized studies are just beginning to mature. Patients with intermediate or high-risk tumors should receive neoadjuvant (NHT) and adjuvant (AHT) androgen deprivation. Bolla et al. could show an increase in 5-year overall survival from 62-78%. The inclusion of the whole pelvis in the treatment field (WPRT) is still controversial. The RTOG 94-13 study showed a significant advantage in disease-free survival after 60 months but long-term data did not yield significant differences between WPRT and irradiation of the prostate alone. The German Society of Urology strongly recommends adjuvant radiotherapy of the prostate bed for pT3 N0 tumors with positive margins. In a pT3 N0 R0 or pT2 N0 R+ situation, adjuvant radiotherapy should at least be considered. So far, no randomized data on NHT and AHT have been published, so androgen deprivation remains an individual decision in the postoperative setting. In a retrospective analysis Spiotto et al. reported a positive effect for adjuvant WPRT and biochemical control. This article summarizes the essential publications on definitive and adjuvant radiotherapy and discusses the additional use of androgen deprivation and WPRT. (orig.) [German] Die Entwicklung der intensitaetsmodulierten Radiotherapie (IMRT) ermoeglichte in den letzten Jahren eine Dosiseskalation bei der primaeren Radiotherapie des Prostatakarzinoms und damit eine Verbesserung

  13. Particle acceleration by plasma

    CERN Document Server

    Ogata, A

    2002-01-01

    Plasma acceleration is carried out by using potential of plasma wave. It is classified by generation method of plasma wave such as the laser wake-field acceleration and the beat wave acceleration. Other method using electron beam is named the plasma wake-field acceleration (or beam wake-field acceleration). In this paper, electron acceleration by laser wake-field in gas plasma, ion source by laser radiation of solid target and nanoion beam generation by one component of plasma in trap are explained. It is an applicable method that ions, which run out from the solid target irradiated by laser, are used as ion source of accelerator. The experimental system using 800 nm laser, 50 mJ pulse energy and 50 fs pulse width was studied. The laser intensity is 4x10 sup 1 sup 6 Wcm sup - sup 2 at the focus. The target film of metal and organic substance film was used. When laser irradiated Al target, two particles generated, in front and backward. It is new fact that the neutral particle was obtained in front, because it...

  14. The miniature accelerator

    CERN Multimedia

    Antonella Del Rosso

    2015-01-01

    The image that most people have of CERN is of its enormous accelerators and their capacity to accelerate particles to extremely high energies. But thanks to some cutting-edge studies on beam dynamics and radiofrequency technology, along with innovative construction techniques, teams at CERN have now created the first module of a brand-new accelerator, which will be just 2 metres long. The potential uses of this miniature accelerator will include deployment in hospitals for the production of medical isotopes and the treatment of cancer. It’s a real David-and-Goliath story.   Serge Mathot, in charge of the construction of the "mini-RFQ", pictured with the first of the four modules that will make up the miniature accelerator. The miniature accelerator consists of a radiofrequency quadrupole (RFQ), a component found at the start of all proton accelerator chains around the world, from the smallest to the largest. The LHC is designed to produce very high-intensity beams ...

  15. Cosmic particle acceleration

    Energy Technology Data Exchange (ETDEWEB)

    Zimbardo, Gaetano; Perri, Silvia [Universita della Calabria, Dipartimento di Fisica, 87036 Rende (Italy)

    2014-07-01

    The most popular mechanism for the acceleration of cosmic rays, which is thought to operate in supernova remnant shocks as well as at heliospheric shocks, is the diffusive shock acceleration, which is a Fermi mechanism based on normal diffusion. On the other hand, in the last few years it has been shown that the transport of plasma particles in the presence of electric and magnetic turbulence can be superdiffusive rather than normal diffusive. The term 'superdiffusive' refers to the mean square displacement of particle positions growing superlinearly with time, as compared to the normal linear growth. In particular, superdiffusion is characterized by a non Gaussian statistical process called Levy random walk. We show how diffusive shock acceleration is modified by superdiffusion, and how this yields new predictions for the cosmic ray spectral index, for the acceleration time, and for the spatial profile of energetic particles. A comparison with observations of particle acceleration at heliospheric shocks and at supernova remnant shocks is done. We discuss how superdiffusive shock acceleration allows to explain the observations of hard ion spectra at the solar wind termination shock detected by Voyager 2, of hard radio spectra due to synchrotron emission of electrons accelerated at supernova remnant shocks, and how it can help to explain the observations of 'thin rims' in the X-ray synchrotron emission.

  16. Multicavity proton cyclotron accelerator

    Directory of Open Access Journals (Sweden)

    J. L. Hirshfield

    2002-08-01

    Full Text Available A mechanism for acceleration of protons is described, in which energy gain occurs near cyclotron resonance as protons drift through a sequence of rotating-mode TE_{111} cylindrical cavities in a strong nearly uniform axial magnetic field. Cavity resonance frequencies decrease in sequence from one another with a fixed frequency interval Δf between cavities, so that synchronism can be maintained between the rf fields and proton bunches injected at intervals of 1/Δf. An example is presented in which a 122 mA, 1 MeV proton beam is accelerated to 961 MeV using a cascade of eight cavities in an 8.1 T magnetic field, with the first cavity resonant at 120 MHz and with Δf=8 MHz. Average acceleration gradient exceeds 40 MV/m, average effective shunt impedance is 223 MΩ/m, but maximum surface field in the cavities does not exceed 7.2 MV/m. These features occur because protons make many orbital turns in each cavity and thus experience acceleration from each cavity field many times. Longitudinal and transverse stability appear to be intrinsic properties of the acceleration mechanism, and an example to illustrate this is presented. This acceleration concept could be developed into a proton accelerator for a high-power neutron spallation source, such as that required for transmutation of nuclear waste or driving a subcritical fission burner, provided a number of significant practical issues can be addressed.

  17. Histomorphological changes of vessel structure in head and neck vessels following preoperative or postoperative radiotherapy; Histomorphologische Strukturveraenderungen von Kopf-Hals-Gefaessen nach prae- oder postoperativer Radiotherapie

    Energy Technology Data Exchange (ETDEWEB)

    Schultze-Mosgau, S.; Wehrhan, F.; Wiltfang, J. [Klinik und Poliklinik fuer Mund-, Kiefer-, Gesichtschirurgie, Friedrich-Alexander-Univ. Erlangen-Nuernberg (Germany); Grabenbauer, G.G.; Sauer, R.; Roedel, F. [Klinik und Poliklinik fuer Strahlentherapie, Friedrich-Alexander-Univ. Erlangen-Nuernberg (Germany); Radespiel-Troeger, M. [Inst. fuer Medizinische Informatik, Biometrie und Epidemiologie, Friedrich-Alexander-Univ. Erlangen-Nuernberg (Germany)

    2002-06-01

    dose of 40-50 Gy and chemotherapy given at a median interval of 1.5 months prior to operation did not lead to significant histological changes to the recipient vessels. (orig.) [German] Im Zeitraum von Oktober 1995 bis Maerz 2002 wurden insgesamt 348 Patienten mit 356 freien mikrovaskulaeren Hart- und Weichgewebetransplantaten primaer oder sekundaer rekonstruiert. In Abhaengigkeit von der strahlentherapeutischen Vorbehandlung wurde folgende Gruppeneinteilung vorgenommen: Gruppe 1 = Patienten (n = 27) mit ausschliesslich chirurgischer Behandlung. Gruppe 2 = Patienten (n = 29) mit einer neoadjuvanten Radiochemotherapie (40-50 Gy; 800 mg/m{sup 2} 5-Fluorouracil [5-FU] und 20 mg/m{sup 2} Cisplatin) und primaerer Rekonstruktion. Gruppe 3 = Patienten (n = 20) mit vorausgegangener Radiotherapie, (60-70 Gy) und sekundaerer Rekonstruktion. 209 Gefaessproben der Anschluss- und Transplantatgefaesse wurden qualitativ histologisch auf Veraenderungen der Media und Intima sowie quantitativ histomorphometrisch (NIH-Image) auf eine anteilige Zu- oder Abnahme der Media, der Intima oder des Lumens am Gesamtquerschnitt des Gefaesses untersucht (ANOVA SPSS V9). Ergebnisse: Die Ergebnisse zeigten ein signifikantes Ueberwiegen von Gefaessveraenderungen des Grades II (Hyalinose der Media und Intima und eine Intimaabloesung, p = 0,009) an den Anschlussarterien in der Gruppe 3 (praeoperative Radiotherapie mit 60-70 Gy). An Transplantatarterien (p = 0,127), Anschluss- (p = 0,43) und Transplantatvenen (p = 0,54) wurden keine signifikanten qualitativen Gefaesswandveraenderungen zwischen einer vorausgegangenen Radiotherapie und keiner Bestrahlung gesehen. Bei der Analyse der Anschlussarterien war die Ratio Media/Gesamtflaeche in Gruppe 3 (Median 0,51; IQR 0,10) signifikant kleiner als in Gruppe 1 (p = 0,02) (Median 0,61; IQR 0,29) und Gruppe 2 (p = 0,046) (Median 0,58; IQR 0,19). Ein signifikanter Unterschied der Ratio Lumen/Gesamtflaeche zeigte sich zwischen Gruppe 1 und 3 (p = 0,01) (Gruppe 1

  18. The Results of Radiotherapy in Locally Advanced

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Hyun Soo; Kang, Seung Hee; Kim, Sang Won; Jun, Mi Seon; Jo, Seon Mi; Lim, Jun Cheol; Oh, Young Taek; Kang, Seock Yoon [Ajou University School of Medicine, Suwon (Korea, Republic of)

    2009-09-15

    We retrospectively studied the outcomes and prognostic factors of patients with locally advanced, unresectable pancreatic cancer who were treated with concurrent chemoradiotherapy (CCRT) or radiotherapy only. Fifty-one patients with locally advanced, unresectable pancreatic cancer (stage IIA{approx}III) who received radiotherapy ({>=}30 Gy) between January 1994 and August 2008 were reviewed retrospectively. The median radiation dose was 39 Gy. Chemotherapy consisted of gemcitabine, cisplatin, or 5-FU alone or in various combinations, and was administered concurrently with radiotherapy in 38 patients. The follow-up period ranged from 2{approx}40 months (median, 8 months). The median survival, and the 1-and 2-year overall survival (OS) rates were 7 months, 15.7%, and 5.9%, respectively. Based on univariate analysis, the baseline CA19-9, performance status, and chemotherapy regimen were significant prognostic factors. The median survival was 8 months for CCRT, and 6 months for radiotherapy alone. The patients treated with gemcitabine-containing regimens had longer survival (median, 10 months) than the patients treated with radiotherapy alone (p=0.027). Twenty-three patients were available to evaluate the patterns of failure. Distant metastases (DM) occurred in 18 patients and regional recurrences were demonstrated in 4 patients. Local progression developed in 14 patients. We analyzed the association between the time-to-DM and the baseline CA19-9 levels for 18 evaluable patients. The median time-to-DM was 20 months for patients with normal baseline CA19-9 levels and 2 months for patients with baseline CA19-9 levels {>=}200 U/ml. CCRT with gemcitabine-based regimens was effective in improving OS in patients with locally advanced, unresectable pancreatic cancer. We suggest that the baseline CA19-9 level is valuable in determining the treatment strategy for patients with locally advanced, unresectable pancreatic cancer.

  19. Application of Accelerators and Storage Rings: Accelerators in Medicine

    CERN Document Server

    Amaldi, U

    2013-01-01

    This document is part of Subvolume C 'Accelerators and Colliders' of Volume 21 'Elementary Particles' of Landolt-Börnstein - Group I 'Elementary Particles, Nuclei and Atoms'. It contains the the Section '11.3 Accelerators in Medicine' of the Chapter '11 Application of Accelerators and Storage Rings' with the content: 11.3 Accelerators in Medicine 11.3.1 Accelerators and Radiopharmaceuticals 11.3.2 Accelerators and Cancer Therapy

  20. Confronting Twin Paradox Acceleration

    Science.gov (United States)

    Murphy, Thomas W.

    2016-05-01

    The resolution to the classic twin paradox in special relativity rests on the asymmetry of acceleration. Yet most students are not exposed to a satisfactory analysis of what exactly happens during the acceleration phase that results in the nonaccelerated observer's more rapid aging. The simple treatment presented here offers both graphical and quantitative solutions to the problem, leading to the correct result that the acceleration-induced age gap is 2Lβ years when the one-way distance L is expressed in light-years and velocity β ≡v/c .

  1. [Exchange of medical imaging and data information in radiotherapy: needs, methods and current limits].

    Science.gov (United States)

    Manens, J P

    1997-01-01

    standardized transfer of most of the information wich circulates in a radiotherapy department. A wide range of device types are represented, (treatment planning systems, portal imaging devices, linear accelerators, recording and verifying systems, conventional and virtual simulators). There will be additions and perhaps new developments in dataflow management, more complete integration with HIS/RIS system and printing, but the lion's share of the work has now been done. A project to integrate some security features into the Dicom protocol has begun.

  2. Shielding considerations for an operating room based intraoperative electron radiotherapy unit.

    Science.gov (United States)

    Mills, M D; Almond, P R; Boyer, A L; Ochran, T G; Madigan, W; Rich, T A; Dally, E B

    1990-05-01

    The leakage radiation characteristics of a dedicated intraoperative radiotherapy linear accelerator have been measured on a machine designed to minimize the shielding required to allow it to be placed in an operating room suite. The scattering foil design was optimized to produce a flat beam for the field sizes employed while generating minimal bremsstrahlung contamination over the available energy range. More lead shielding was used in the treatment head than is used in conventional accelerators. A small amount of borated polyethylene shielding was also employed since neutron production was present at measurable levels. The room shielding installed in the operating room was demonstrated to be adequate to treat at least 20 patients each month to an average dose of 20 Gy. The worst case exposure was found to be 73% maximum permissible exposure. Administrative control was required for adjoining areas when calibrations and maintenance were performed.

  3. Radiation exposure of personnel during intraoperative radiotherapy (IORT): radiation protection aspects.

    Science.gov (United States)

    Strigari, L; Soriani, A; Landoni, V; Teodoli, S; Bruzzaniti, V; Benassi, M

    2004-09-01

    Intraoperative radiotherapy (IORT) is a multidisciplinary procedure which combines two conventional methods of cancer treatment surgery and radiation therapy. The purpose is to deliver a large single dose to the surgically exposed tumor bed while minimizing doses to normal tissues. Intraoperative radiation therapy (IORT) is a technique which allows irradiating the patient directly after the surgical operation using a linear accelerator that can be situated in the operating room. For medical accelerators with energy over 10MeV the need to characterize the neutron spectra for this particular situation arises from the fact that, when neutron spectra is not fully known, it becomes necessary to be more cautious introducing a weight factor wR of 20 (maximum value). This leads to overesteem the equivalent dose due to neutrons and it indicates to introduce additional (mobile) shields for photon and neutrons radiation not easily achievable in an operating room.

  4. Development of C⁶⁺ laser ion source and RFQ linac for carbon ion radiotherapy.

    Science.gov (United States)

    Sako, T; Yamaguchi, A; Sato, K; Goto, A; Iwai, T; Nayuki, T; Nemoto, K; Kayama, T; Takeuchi, T

    2016-02-01

    A prototype C(6+) injector using a laser ion source has been developed for a compact synchrotron dedicated to carbon ion radiotherapy. The injector consists of a laser ion source and a 4-vane radio-frequency quadrupole (RFQ) linac. Ion beams are extracted from plasma and directly injected into the RFQ. A solenoid guides the low-energy beams into the RFQ. The RFQ is designed to accelerate high-intensity pulsed beams. A structure of monolithic vanes and cavities is adopted to reduce its power consumption. In beam acceleration tests, a solenoidal magnetic field set between the laser ion source and the RFQ helped increase both the peak currents before and after the RFQ by a factor of 4.

  5. Development of C6+ laser ion source and RFQ linac for carbon ion radiotherapy

    Science.gov (United States)

    Sako, T.; Yamaguchi, A.; Sato, K.; Goto, A.; Iwai, T.; Nayuki, T.; Nemoto, K.; Kayama, T.; Takeuchi, T.

    2016-02-01

    A prototype C6+ injector using a laser ion source has been developed for a compact synchrotron dedicated to carbon ion radiotherapy. The injector consists of a laser ion source and a 4-vane radio-frequency quadrupole (RFQ) linac. Ion beams are extracted from plasma and directly injected into the RFQ. A solenoid guides the low-energy beams into the RFQ. The RFQ is designed to accelerate high-intensity pulsed beams. A structure of monolithic vanes and cavities is adopted to reduce its power consumption. In beam acceleration tests, a solenoidal magnetic field set between the laser ion source and the RFQ helped increase both the peak currents before and after the RFQ by a factor of 4.

  6. Development of C{sup 6+} laser ion source and RFQ linac for carbon ion radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Sako, T., E-mail: takayuki1.sako@toshiba.co.jp; Yamaguchi, A.; Sato, K. [Toshiba Corporation, Yokohama 235-8522 (Japan); Goto, A.; Iwai, T.; Nayuki, T.; Nemoto, K.; Kayama, T. [Cancer Research Center, Yamagata University Faculty of Medicine, Yamagata 990-9585 (Japan); Takeuchi, T. [Accelerator Engineering Corporation, Chiba 263-0043 (Japan)

    2016-02-15

    A prototype C{sup 6+} injector using a laser ion source has been developed for a compact synchrotron dedicated to carbon ion radiotherapy. The injector consists of a laser ion source and a 4-vane radio-frequency quadrupole (RFQ) linac. Ion beams are extracted from plasma and directly injected into the RFQ. A solenoid guides the low-energy beams into the RFQ. The RFQ is designed to accelerate high-intensity pulsed beams. A structure of monolithic vanes and cavities is adopted to reduce its power consumption. In beam acceleration tests, a solenoidal magnetic field set between the laser ion source and the RFQ helped increase both the peak currents before and after the RFQ by a factor of 4.

  7. Description of the phenotypes of 63 heterozygous, homozygous and compound heterozygous patients carrying the Hb Groene Hart [α119(H2)Pro→Ser; HBA1: c.358C>T] variant.

    Science.gov (United States)

    Joly, Philippe; Lacan, Philippe; Garcia, Caroline; Francina, Alain

    2014-01-01

    We here report the phenotypes and genotypes of 63 patients of North African origin, carriers of Hb Groene Hart [Hb GH, α119(H2)Pro → Ser; HBA1: c.358C>T], an α(+)-thalassemia (α(+)-thal) hemoglobin (Hb) variant. Fifty patients were heterozygous, five were homozygous and eight also carried the common -α(3.7) (rightward) deletion in compound heterozygosity. The expression of the α(GH)-globin chain is increased in the following order: heterozygous, compound heterozygous and homozygous. Parallel significant changes of mean corpuscular Hb (MCH) and mean corpuscular volume (MCV) were also observed. Our large cohort of Hb GH carriers could have been obtained by the systematic realization of globin chain separation by reversed phase liquid chromatography (RP-LC) in our routine Hb testing.

  8. Evaluación del comportamiento físico y químico poscosecha del plátano dominico Hartón (musa aab simmonds) cultivado en el municipio de Belalcázar (Caldas)

    OpenAIRE

    Mejía Gutiérrez, Luis Fernando

    2013-01-01

    Este trabajo se realizó con frutos de plátano Dominico Hartón (Musa AAB Simmonds) cultivados en el municipio de Belalcázar (Caldas), entre las cotas 900-1.200 m.s.n.m., con precipitación promedia en el rango 1.800-2.000 mm por año. Las temperaturas medias en el municipio se han estimado para las zonas bajas en 24°C; para las más altas en 18°C. Los frutos fueron cosechados a las 14, 15, 16, 17 y 18 semanas desde floración, en invierno y transportados a los laboratorios de la Universidad de ...

  9. Ion acceleration through radiation pressure in quanto-electrodynamical regimes

    Science.gov (United States)

    Del Sorbo, Dario; Ridgers, Chris; Laser Plasmas; Fusion Team

    2016-10-01

    The strong radiation pressure carried by high-intensity lasers interacting with plasmas can accelerate ions over very short distances. The resulting compact particle accelerator could find applications in medical physics (radiotherapy) as well as in fundamental physics (hadron interactions). With next-generation multi-petawatt lasers, reaching focused intensity 1023Wcm-2 , ions could potentially reach GeV energies. However, the physics of laser-matter interactions at these extreme intensities is not well understood. In particular, on acceleration by the electromagnetic fields of the laser, the electrons in the plasma start to radiate hard photons prolifically. These hard photons can decay to electron-positron pairs, a cascade of pair production can ensue leading to the formation of an over-dense pair plasma which can absorb the laser-pulse. We have developed a self-consistent theory for both hole boring and light sail radiation pressure ion-acceleration, accounting for radiation-reaction and pair-creation. We show that the key role is played by a pair plasma that arises between the laser and the accelerated ions, strongly modifying the laser absorption.

  10. A Variable Energy CW Compact Accelerator for Ion Cancer Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Johnstone, Carol J. [Fermilab; Taylor, J. [Huddersfield U.; Edgecock, R. [Huddersfield U.; Schulte, R. [Loma Linda U.

    2016-03-10

    Cancer is the second-largest cause of death in the U.S. and approximately two-thirds of all cancer patients will receive radiation therapy with the majority of the radiation treatments performed using x-rays produced by electron linacs. Charged particle beam radiation therapy, both protons and light ions, however, offers advantageous physical-dose distributions over conventional photon radiotherapy, and, for particles heavier than protons, a significant biological advantage. Despite recognition of potential advantages, there is almost no research activity in this field in the U.S. due to the lack of clinical accelerator facilities offering light ion therapy in the States. In January, 2013, a joint DOE/NCI workshop was convened to address the challenges of light ion therapy [1], inviting more than 60 experts from diverse fields related to radiation therapy. This paper reports on the conclusions of the workshop, then translates the clinical requirements into accelerat or and beam-delivery technical specifications. A comparison of available or feasible accelerator technologies is compared, including a new concept for a compact, CW, and variable energy light ion accelerator currently under development. This new light ion accelerator is based on advances in nonscaling Fixed-Field Alternating gradient (FFAG) accelerator design. The new design concepts combine isochronous orbits with long (up to 4m) straight sections in a compact racetrack format allowing inner circulating orbits to be energy selected for low-loss, CW extraction, effectively eliminating the high-loss energy degrader in conventional CW cyclotron designs.

  11. Evaluation of IMRT treatments performed in Rio de Janeiro radiotherapy services

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Roberto Salomon de, E-mail: salomon@inca.gov.br [Instituto Nacional de Cancer (PQRT/INCA), Rio de Janeiro, RJ (Brazil). Programa de Qualidade em Radioterapia; Rosa, Luiz A.R. da, E-mail: lrosa@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Braz, Delson, E-mail: delson@lin.ufrj.br [Coordenacao dos Programas de Pos-Graduacao em Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil)

    2013-07-01

    The Radiotherapy Quality Program (PQRT) of the Brazilian National Cancer Institute (INCA) has developed a phantom for quality control in IMRT and has implemented it in its routine. It must be sent or taken to the participating institutions to be irradiated under certain conditions and then be returned to the PQRT, where the discrepancy degree between the planned treatment and those effectively delivered will be evaluated. This work aims to show the results of the use of this system to evaluate those radiotherapy services in Rio de Janeiro that perform the IMRT technique. To evaluate the conformity between the planned and delivered dose in the planning target volume (PTV) we have considered two parameters: absorbed dose measured with thermoluminescence dosimeters (TLD) and gamma index of the dose distribution, measured with radiochromic films and a dose analysis software. We have evaluated all the radiotherapy services in Rio de Janeiro that performed the IMRT technique until the period of end of 2011 and the beginning of 2012. Among the nine linear accelerators evaluated, 33,3% of them were out of ± 3% for measured dose in PTV and 50% of them less than 95% of conformity for the 5%-3mm gamma index for the dose distribution. Although IMRT is a high precision radiotherapy technique and its use has spread out quickly over the world, its quality control still needs more attention, as demonstrated with the numbers presented in this work. This sample held in Rio de Janeiro can be extrapolated to other sites that perform the IMRT technique and its use in these services also need to be evaluated. (author)

  12. WE-EF-BRD-01: Past, Present and Future: MRI-Guided Radiotherapy From 2005 to 2025

    Energy Technology Data Exchange (ETDEWEB)

    Lagendijk, J. [University Medical Center Utrecht (Netherlands)

    2015-06-15

    MRI-guided treatment is a growing area of medicine, particularly in radiotherapy and surgery. The exquisite soft tissue anatomic contrast offered by MRI, along with functional imaging, makes the use of MRI during therapeutic procedures very attractive. Challenging the utility of MRI in the therapy room are many issues including the physics of MRI and the impact on the environment and therapeutic instruments, the impact of the room and instruments on the MRI; safety, space, design and cost. In this session, the applications and challenges of MRI-guided treatment will be described. The session format is: Past, present and future: MRI-guided radiotherapy from 2005 to 2025: Jan Lagendijk Battling Maxwell’s equations: Physics challenges and solutions for hybrid MRI systems: Paul Keall I want it now!: Advances in MRI acquisition, reconstruction and the use of priors to enable fast anatomic and physiologic imaging to inform guidance and adaptation decisions: Yanle Hu MR in the OR: The growth and applications of MRI for interventional radiology and surgery: Rebecca Fahrig Learning Objectives: To understand the history and trajectory of MRI-guided radiotherapy To understand the challenges of integrating MR imaging systems with linear accelerators To understand the latest in fast MRI methods to enable the visualisation of anatomy and physiology on radiotherapy treatment timescales To understand the growing role and challenges of MRI for image-guided surgical procedures My disclosures are publicly available and updated at: http://sydney.edu.au/medicine/radiation-physics/about-us/disclosures.php.

  13. Should elderly patients with glioblastoma be proposed to radiotherapy?; Faut-il irradier les glioblastomes chez les patients ages?

    Energy Technology Data Exchange (ETDEWEB)

    Lopez, S.; Taillibert, S.; Idbaih, A.; Simon, J.M.; Mazeron, J.J. [Groupe Hospitalier Pitie-Salpetriere, Service d' Oncologie Radiotherapique, Centre des Tumeurs, 75 -Paris (France)

    2008-12-15

    In glioblastoma multiform-patients, advanced age has been associated with poor prognosis and decreased tolerance to treatments. The optimal management, especially with irradiation, was not definitively determined in the eighth and ninth decades. The Association of French-speaking neuro-oncologists (Anocef) has recently conducted a randomized clinical trial comparing radiotherapy plus supportive care versus supportive care alone in such patients. Patients aged 70-years and older with newly diagnosed glioblastoma and a Karnofsky performance score of 70 or above were randomly assigned to receive focal irradiation in daily fraction of 1.8 Gy given five days per week for a total dose of 50 Gy plus supportive care or supportive care only. Radiotherapy resulted in a modest but significant improvement in overall survival without reducing quality of life or cognition. However, the optimal regimen of radiotherapy in this fragile population remains uncertain. Abbreviated course of radiotherapy (40 Gy in 15 fractions over 19 days) has been proposed. Analysis of preliminary results showed that efficacy and safety of this hypo-fractionated accelerated regimen compared favourably with those of classically fractionated treatments. Finally, the potential contribution of surgery and chemotherapy should be evaluated in prospective clinical trials. (authors)

  14. Accuracy in the reproducibility of daily patients' setup in 3D conformal radiotherapy for prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Giordani, Adelmo Jose; Dias, Rodrigo Souza; Segreto, Roberto Araujo, E-mail: adelmogiordani@ig.com.b [Universidade Federal de Sao Paulo (UNIFESP), SP (Brazil). Unidade de Radioterapia; Segreto, Helena Regina Comodo [Universidade Federal de Sao Paulo (UNIFESP), SP (Brazil). Dept. de Oncologia Clinica e Experimental

    2010-07-15

    Objective: to evaluate the reproducibility of daily patients' setup in 3D conformal radiotherapy for prostate cancer. Materials and methods: the present study evaluated a total of 960 radiological images (anterior and lateral views) of 120 patients submitted to conformal radiotherapy for prostate cancer with the isocentric technique. A 6 MV particle accelerator was utilized in the process. A specific protocol for prostate radiotherapy planning and treatment was applied, with the patients placed in supine position, hands on the chest and legs placed on and appropriate support. Daily, the patients were positioned according to previously made skin markings in alignment with the in-room laser. The portal images were compared with digitally reconstructed radiographs (DRR) in the Eclipse treatment planning system based on the tomographic images. Radiography was performed at the first day, and weekly afterwards until the treatment was completed. Results: the following average position shifts were observed: 1.99 +- 1.25 mm craniocaudally, 1.37 +- 0.84 mm laterally, and 1.94 +- 1.10 mm anteroposteriorly. Conclusion: the use of specific protocols for patients' setup is feasible in the clinical practice, allowing appropriate reproducibility and quick correction of possible errors in conformal radiotherapy for prostate cancer. (author)

  15. Vibration control in accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Montag, C.

    2011-01-01

    In the vast majority of accelerator applications, ground vibration amplitudes are well below tolerable magnet jitter amplitudes. In these cases, it is necessary and sufficient to design a rigid magnet support structure that does not amplify ground vibration. Since accelerator beam lines are typically installed at an elevation of 1-2m above ground level, special care has to be taken in order to avoid designing a support structure that acts like an inverted pendulum with a low resonance frequency, resulting in untolerable lateral vibration amplitudes of the accelerator components when excited by either ambient ground motion or vibration sources within the accelerator itself, such as cooling water pumps or helium flow in superconducting magnets. In cases where ground motion amplitudes already exceed the required jiter tolerances, for instance in future linear colliders, passive vibration damping or active stabilization may be considered.

  16. Compact particle accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Elizondo-Decanini, Juan M.

    2017-08-29

    A compact particle accelerator having an input portion configured to receive power to produce particles for acceleration, where the input portion includes a switch, is provided. In a general embodiment, a vacuum tube receives particles produced from the input portion at a first end, and a plurality of wafer stacks are positioned serially along the vacuum tube. Each of the plurality of wafer stacks include a dielectric and metal-oxide pair, wherein each of the plurality of wafer stacks further accelerate the particles in the vacuum tube. A beam shaper coupled to a second end of the vacuum tube shapes the particles accelerated by the plurality of wafer stacks into a beam and an output portion outputs the beam.

  17. Rejuvenating CERN's Accelerators

    CERN Multimedia

    2004-01-01

    In the coming years and especially in 2005, CERN's accelerators are going to receive an extensive renovation programme to ensure they will perform reliably and effectively when the LHC comes into service.

  18. Joint International Accelerator School

    CERN Multimedia

    CERN Accelerator School

    2014-01-01

    The CERN and US Particle Accelerator Schools recently organised a Joint International Accelerator School on Beam Loss and Accelerator Protection, held at the Hyatt Regency Hotel, Newport Beach, California, USA from 5-14 November 2014. This Joint School was the 13th in a series of such schools, which started in 1985 and also involves the accelerator communities in Japan and Russia.   Photo courtesy of Alfonse Pham, Michigan State University.   The school attracted 58 participants representing 22 different nationalities, with around half from Europe and the other half from Asia and the Americas. The programme comprised 26 lectures, each of 90 minutes, and 13 hours of case study. The students were given homework each day and had an opportunity to sit a final exam, which counted towards university credit. Feedback from the participants was extremely positive, praising the expertise and enthusiasm of the lecturers, as well as the high standard and quality of their lectures. Initial dis...

  19. Dielectric assist accelerating structure

    Science.gov (United States)

    Satoh, D.; Yoshida, M.; Hayashizaki, N.

    2016-01-01

    A higher-order TM02 n mode accelerating structure is proposed based on a novel concept of dielectric loaded rf cavities. This accelerating structure consists of ultralow-loss dielectric cylinders and disks with irises which are periodically arranged in a metallic enclosure. Unlike conventional dielectric loaded accelerating structures, most of the rf power is stored in the vacuum space near the beam axis, leading to a significant reduction of the wall loss, much lower than that of conventional normal-conducting linac structures. This allows us to realize an extremely high quality factor and a very high shunt impedance at room temperature. A simulation of a 5 cell prototype design with an existing alumina ceramic indicates an unloaded quality factor of the accelerating mode over 120 000 and a shunt impedance exceeding 650 M Ω /m at room temperature.

  20. Laser-driven particle acceleration towards radiobiology and medicine

    CERN Document Server

    2016-01-01

    This book deals with the new method of laser-driven acceleration for application to radiation biophysics and medicine. It provides multidisciplinary contributions from world leading scientist in order to assess the state of the art of innovative tools for radiation biology research and medical applications of ionizing radiation. The book contains insightful contributions on highly topical aspects of spatio-temporal radiation biophysics, evolving over several orders of magnitude, typically from femtosecond and sub-micrometer scales. Particular attention is devoted to the emerging technology of laser-driven particle accelerators and their applicatio to spatio-temporal radiation biology and medical physics, customization of non-conventional and selective radiotherapy and optimized radioprotection protocols.