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Sample records for standard clinical dose

  1. Low-dose versus standard-dose CT protocol in patients with clinically suspected renal colic.

    Science.gov (United States)

    Poletti, Pierre-Alexandre; Platon, Alexandra; Rutschmann, Olivier T; Schmidlin, Franz R; Iselin, Christophe E; Becker, Christoph D

    2007-04-01

    The purpose of our study was to compare a low-dose abdominal CT protocol, delivering a dose of radiation close to the dose delivered by abdominal radiography, with standard-dose unenhanced CT in patients with suspected renal colic. One hundred twenty-five patients (87 men, 38 women; mean age, 45 years) who were admitted with suspected renal colic underwent both abdominal low-dose CT (30 mAs) and standard-dose CT (180 mAs). Low-dose CT and standard-dose CT were independently reviewed, in a delayed fashion, by two radiologists for the characterization of renal and ureteral calculi (location, size) and for indirect signs of renal colic (renal enlargement, pyeloureteral dilatation, periureteral or renal stranding). Results reported for low-dose CT, with regard to the patients' body mass indexes (BMIs), were compared with those obtained with standard-dose CT (reference standard). The presence of non-urinary tract-related disorders was also assessed. Informed consent was obtained from all patients. In patients with a BMI 3 mm. Low-dose CT was 100% sensitive and specific for depicting non-urinary tract-related disorders (n = 6). Low-dose CT achieves sensitivities and specificities close to those of standard-dose CT in assessing the diagnosis of renal colic, depicting ureteral calculi > 3 mm in patients with a BMI < 30, and correctly identifying alternative diagnoses.

  2. Postimplant Dosimetry Using a Monte Carlo Dose Calculation Engine: A New Clinical Standard

    International Nuclear Information System (INIS)

    Carrier, Jean-Francois; D'Amours, Michel; Verhaegen, Frank; Reniers, Brigitte; Martin, Andre-Guy; Vigneault, Eric; Beaulieu, Luc

    2007-01-01

    Purpose: To use the Monte Carlo (MC) method as a dose calculation engine for postimplant dosimetry. To compare the results with clinically approved data for a sample of 28 patients. Two effects not taken into account by the clinical calculation, interseed attenuation and tissue composition, are being specifically investigated. Methods and Materials: An automated MC program was developed. The dose distributions were calculated for the target volume and organs at risk (OAR) for 28 patients. Additional MC techniques were developed to focus specifically on the interseed attenuation and tissue effects. Results: For the clinical target volume (CTV) D 90 parameter, the mean difference between the clinical technique and the complete MC method is 10.7 Gy, with cases reaching up to 17 Gy. For all cases, the clinical technique overestimates the deposited dose in the CTV. This overestimation is mainly from a combination of two effects: the interseed attenuation (average, 6.8 Gy) and tissue composition (average, 4.1 Gy). The deposited dose in the OARs is also overestimated in the clinical calculation. Conclusions: The clinical technique systematically overestimates the deposited dose in the prostate and in the OARs. To reduce this systematic inaccuracy, the MC method should be considered in establishing a new standard for clinical postimplant dosimetry and dose-outcome studies in a near future

  3. Comparison of ESD and major organ absorbed doses of 5 year old standard guidekines and clinical exposure conditions

    Energy Technology Data Exchange (ETDEWEB)

    Kang, A Ram; Ahn, Sung Min [Dept. of Radiological Science, The Graduate School, Gachon University, Incheon (Korea, Republic of); Lee, In Ja [Dept. of Radiologic technology, Dongnam health University, Suwon (Korea, Republic of)

    2017-09-15

    Pediatrics are more sensibility to radiation than adults and because they are organs that are not completely grown, they have a life expectancy that can be adversely affected by exposure. Therefore, the management of exposure dose is more important than the case of adult. The purpose of this study was to determine the suitability of the 10 year old phantom for the 5 year old pediatric's recommendation and the incident surface dose, and to measure the organ absorbed dose. This study is compared the organ absorbed dose and the entrance surface dose in the clinical conditions at 5 and 10 years old pediatric. Clinical 5 year old condition was slightly higher than recommendation condition and 10 year old condition was very high. In addition, recommendation condition ESD was found to be 43% higher than the ESD of the 5 year old group and the ESD of the 10 year old group was 126% higher than that of the 5 year old group. The recommended ESD at 5 years old and the ESD according to clinical imaging conditions were 31.6%. There was no significant difference between the 5 year old recommended exposure conditions and the organ absorbed dose due to clinical exposure conditions, but there was a large difference between the Chest and Pelvic. However, it was found that there was a remarkable difference when comparing the organ absorbed dose by 10 year clinical exposure conditions. Therefore, more detailed standard exposure dose for the recommended dose of pediatric should be studied.

  4. QCM-D surpassing clinical standard for the dose administration of new oral anticoagulant in the patient of coagulation disorders.

    Science.gov (United States)

    Hussain, Munawar; Wendel, Hans Peter; Schmidt, Katrin; Langer, Elisabeth; Körber, Mareike Kristina; Faul, Oksana; Northoff, Hinnak; von Heymann, Christian; Gehring, Frank K

    2018-05-01

    The study focuses the dose administration of dabigatran to avoid the deaths due to hemorrhagic complications and thromboembolic stroke in clinics worldwide. To target the issue, a novel emerging acoustic technology, namely ''Quartz Crystal Microbalance with Dissipation'' (QCM-D) has been applied, while the acoustic assays namely ''activated Partial Thromboplastin Time'' (aPTT) and ''Prothrombinase complex-induced Clotting Test'' (PiCT) have been compared with the standard methods in parallel. Both techniques have been applied to 300 samples, including 220 plasma samples of patients suffering coagulation disorders and 80 plasma samples of non-patients. In comparison, the coagulation times of the acoustic aPTT and PiCT yielded an excellent correlation with the standard methods with in analytical standard deviation limits. Finally, the acoustic aPTT assay is the ''gold standard'' for a dose administration of the new oral anticoagulant, where the Δf/ΔΓ ratio of the acoustic assay demonstrates that dabigatran with FEIBA 50 combination could be a safe remedy to avoid the deaths in clinics. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Randomised clinical trial: high-dose vs. standard-dose proton pump inhibitors for the prevention of recurrent haemorrhage after combined endoscopic haemostasis of bleeding peptic ulcers.

    Science.gov (United States)

    Chen, C-C; Lee, J-Y; Fang, Y-J; Hsu, S-J; Han, M-L; Tseng, P-H; Liou, J-M; Hu, F-C; Lin, T-l; Wu, M-S; Wang, H-P; Lin, J-T

    2012-04-01

    The optimal dosage of intravenous proton pump inhibitors (PPIs) for the prevention of peptic ulcer rebleeding remains unclear. To compare the rebleeding rate of high-dose and standard-dose PPI use after endoscopic haemostasis. A total of 201 patients with bleeding ulcers undergoing endoscopic treatment with epinephrine injection and heater probe thermocoagulation were randomised to receive a high-dose regimen (80 mg bolus, followed by pantoprazole 8 mg/h infusion, n = 100) or a standard-dose regimen (pantoprazole 40 mg bolus daily, n = 101). After 72 h, all patients were given 40 mg pantoprazole daily orally for 27 days. There were no statistical differences in mean units of blood transfused, length of hospitalisation ≦5 days, surgical or radiological interventions and mortality within 30 days between two groups. Bleeding recurred within 30 days in six patients [6.2%, 95% confidence interval (CI) 1.3-11.1%] in the high-dose group, as compared to five patients (5.2%, 95% CI 0.6-9.7%) in the standard-dose group (P = 0.77). The stepwise Cox regression analysis showed end-stage renal disease, haematemesis, chronic obstructive pulmonary disease (hazard ratio: 37.15, 10.07, 9.12, 95% CI: 6.76-204.14, 2.07-49.01, 1.66-50.00 respectively) were independent risk factors for rebleeding and Helicobacter pylori infection was associated with lower risk of rebleeding (hazard ratio: 0.20, 95% CI: 0.04-0.94). Following combined endoscopic haemostasis of bleeding ulcers, co-morbidities, haematemesis and H. pylori Status, but not PPI dosage, are associated with rebleeding (http://www.Clinical Trials.gov.ID: NCT00709046). © 2012 Blackwell Publishing Ltd.

  6. Performance standard for dose Calibrator

    CERN Document Server

    Darmawati, S

    2002-01-01

    Dose calibrator is an instrument used in hospitals to determine the activity of radionuclide for nuclear medicine purposes. International Electrotechnical Commission (IEC) has published IEC 1303:1994 standard that can be used as guidance to test the performance of the instrument. This paper briefly describes content of the document,as well as explains the assessment that had been carried out to test the instrument accuracy in Indonesia through intercomparison measurement.Its is suggested that hospitals acquire a medical physicist to perform the test for its dose calibrator. The need for performance standard in the form of Indonesia Standard is also touched.

  7. An open-label prospective clinical study to assess the efficacy of increasing levocetirizine dose up to four times in chronic spontaneous urticaria not controlled with standard dose.

    Science.gov (United States)

    Sharma, Vinod Kumar; Gupta, Vishal; Pathak, Mona; Ramam, M

    2017-09-01

    The EAACI/GA 2 LEN/EDF/WAO recommendation of increasing antihistamines' dose up to four times in urticaria not adequately controlled with the standard dose is largely based on expert opinion. The objective of this study is to test the current urticaria guidelines of up-dosing antihistamines as second-line treatment. This was an open-label study conducted prospectively on 113 patients with chronic spontaneous urticaria. All patients were treated with sequentially increasing doses of levocetrizine (5 mg, 10 mg, 15 mg and 20 mg/day) every week till the patients became completely asymptomatic or dose of 20 mg/day reached. Urticaria Activity Score (UAS)-7, urticaria-related quality-of-life (CU-Q2oL) and patients' global assessment were used to assess treatment response. Twenty-one (18.58%) patients became asymptomatic with levocetirizine 5 mg/day, while 50 required higher doses of levocetirizine for complete control: 29/92 (31.52%), 6/63 (9.52%) and 15/57 (26.31%) with 10 mg, 15 mg and 20 mg/day, respectively. The percentage of patients experiencing >75% improvement increased with increasing doses of levocetirizine: 26.54%, 53.98%, 60.17% and 69.91% with 5 mg, 10 mg, 15 mg and 20 mg/day, respectively. Sequential up-dosing of levocetirizine produced a progressive improvement in both urticaria control (UAS-7) and quality-of-life (CU-Q2oL) without significantly increasing somnolence. Our results support the current recommendations of increasing antihistamines up to four times the standard dose in patients who fail the first-line treatment.

  8. Evaluation of dose reduction versus standard dosing for maintenance of remission in patients with spondyloarthritis and clinical remission with anti-TNF (REDES-TNF): study protocol for a randomized controlled trial.

    Science.gov (United States)

    Pontes, Caridad; Gratacós, Jordi; Torres, Ferran; Avendaño, Cristina; Sanz, Jesús; Vallano, Antoni; Juanola, Xavier; de Miguel, Eugenio; Sanmartí, Raimon; Calvo, Gonzalo

    2015-08-20

    Dose reduction schedules of tumor necrosis factor antagonists (anti-TNF) as maintenance therapy in patients with spondyloarthritis are used empirically in clinical practice, despite the lack of clinical trials providing evidence for this practice. To address this issue the Spanish Society of Rheumatology (SER) and Spanish Society of Clinical Pharmacology (SEFC) designed a 3-year multicenter, randomized, open-label, controlled clinical trial (2 years for inclusion and 1 year of follow-up). The study is expected to include 190 patients with axial spondyloarthritis on stable maintenance treatment (≥4 months) with any anti-TNF agent at doses recommended in the summary of product characteristics. Patients will be randomized to either a dose reduction arm or maintenance of the dosing regimen as per the official labelling recommendations. Randomization will be stratified according to the anti-TNF agent received before study inclusion. Patient follow-up, visit schedule, and examinations will be maintained as per normal clinical practice recommendations according to SER guidelines. The study aims to test the hypothesis of noninferiority of the dose reduction strategy compared with standard treatment. The first patients were recruited in July 2012, and study completion is scheduled for the end of April 2015. The REDES-TNF study is a pragmatic clinical trial that aims to provide evidence to support a medical decision now made empirically. The study results may help inform clinical decisions relevant to both patients and healthcare decision makers. EudraCT 2011-005871-18 (21 December 2011).

  9. Challenging the One-Dose-Fits-All Model for Insulin in the Acute Treatment of Pediatric Diabetic Ketoacidosis. A Critical Appraisal of "Low-Dose Versus Standard-Dose Insulin in Pediatric Diabetic Ketoacidosis: A Randomized Clinical Trial" by Nallasamy et al (JAMA Pediatrics 2014; 168:999-1005).

    Science.gov (United States)

    Orwoll, Benjamin Edward

    2016-10-01

    To review the findings and discuss the implications of the use of low-dose insulin infusions in pediatric diabetic ketoacidosis compared with standard-dose insulin. A search of the electronic PubMed database was used to perform the clinical query as well as to search for additional relevant literature. The article by Nallasamy K et al "Low-Dose vs Standard-Dose Insulin in Pediatric Diabetic Ketoacidosis: A Randomized Clinical Trial. JAMA Pediatrics 2014; 17:e477-e480" was selected for critical appraisal and literature review. The authors performed a randomized controlled trial among 50 consecutive patients of 0-12 years old presenting to the emergency department in diabetic ketoacidosis. They found that low-dose (0.05 U/kg/hr) insulin infusion was noninferior to standard-dose (0.1 U/kg/hr) insulin in terms of resolution of hyperglycemia and acidosis with a trend toward lower rates of therapy-related complications in the low-dose group. Low-dose insulin infusion is noninferior to standard-dose insulin in the treatment of younger pediatric patients with diabetic ketoacidosis and may lead to fewer therapy-related complications.

  10. Dose-response relationship in clinical oncology

    International Nuclear Information System (INIS)

    Gehan, E.A.

    1984-01-01

    The relationship of dose (and dose rate) to response and toxicity in clinical oncology is reviewed. The concepts expressed by some authors in dose-response studies in animal and human systems are reviewed briefly. Dose rate and tactics of conducting clinical studies are reviewed for both radiotherapy and various types of chemotherapeutic treatment. Examples are given from clinical studies in Hodgkin's disease, acute leukemia, and breast cancer that may prove useful in planning future clinical studies

  11. Radiation dose monitoring in the clinical routine

    Energy Technology Data Exchange (ETDEWEB)

    Guberina, Nika [UK Essen (Germany). Radiology

    2017-04-15

    Here we describe the first clinical experiences regarding the use of an automated radiation dose management software to monitor the radiation dose of patients during routine examinations. Many software solutions for monitoring radiation dose have emerged in the last decade. The continuous progress in radiological techniques, new scan features, scanner generations and protocols are the primary challenge for radiation dose monitoring software systems. To simulate valid dose calculations, radiation dose monitoring systems have to follow current trends and stay constantly up-to-date. The dose management software is connected to all devices at our institute and conducts automatic data acquisition and radiation dose calculation. The system incorporates 18 virtual phantoms based on the Cristy phantom family, estimating doses in newborns to adults. Dose calculation relies on a Monte Carlo simulation engine. Our first practical experiences demonstrate that the software is capable of dose estimation in the clinical routine. Its implementation and use have some limitations that can be overcome. The software is promising and allows assessment of radiation doses, like organ and effective doses according to ICRP 60 and ICRP 103, patient radiation dose history and cumulative radiation doses. Furthermore, we are able to determine local diagnostic reference doses. The radiation dose monitoring software systems can facilitate networking between hospitals and radiological departments, thus refining radiation doses and implementing reference doses at substantially lower levels.

  12. Clinical quality standards for radiotherapy

    Science.gov (United States)

    2012-01-01

    Aim of the study The technological progress that is currently being witnessed in the areas of diagnostic imaging, treatment planning systems and therapeutic equipment has caused radiotherapy to become a high-tech and interdisciplinary domain involving staff of various backgrounds. This allows steady improvement in therapy results, but at the same time makes the diagnostic, imaging and therapeutic processes more complex and complicated, requiring every stage of those processes to be planned, organized, controlled and improved so as to assure high quality of services provided. The aim of this paper is to present clinical quality standards for radiotherapy as developed by the author. Material and methods In order to develop the quality standards, a comparative analysis was performed between European and Polish legal acts adopted in the period of 1980-2006 and the universal industrial ISO 9001:2008 standard, defining requirements for quality management systems, and relevant articles published in 1984-2009 were reviewed, including applicable guidelines and recommendations of American, international, European and Polish bodies, such as the American Association of Physicists in Medicine (AAPM), the European Society for Radiotherapy & Oncology (ESTRO), the International Atomic Energy Agency (IAEA), and the Organisation of European Cancer Institutes (OECI) on quality assurance and management in radiotherapy. Results As a result, 352 quality standards for radiotherapy were developed and categorized into the following three groups: 1 – organizational standards; 2 – physico-technical standards and 3 – clinical standards. Conclusion Proposed clinical quality standards for radiotherapy can be used by any institution using ionizing radiation for medical purposes. However, standards are of value only if they are implemented, reviewed, audited and improved, and if there is a clear mechanism in place to monitor and address failure to meet agreed standards. PMID:23788854

  13. Comparison of the efficacy and safety of intensive-dose and standard-dose statin treatment for stroke prevention

    Science.gov (United States)

    Wang, Juan; Chen, Dan; Li, Da-Bing; Yu, Xin; Shi, Guo-Bing

    2016-01-01

    Abstract Background: Previous study indicated that high-dose statin treatment might increase the risk of hemorrhagic stroke and adverse reactions. We aim to compare the efficacy and safety of intensive-dose and standard-dose statin treatment for preventing stroke in high-risk patients. Methods: A thorough search was performed of multiple databases for publications from 1990 to June 2015. We selected the randomized clinical trials comparing standard-dose statin with placebo and intensive-dose statin with standard-dose statin or placebo for the prevention of stroke events in patients. Duplicate independent data extraction and bias assessments were performed. Data were pooled using a fixed-effects model or a random-effects model if significant heterogeneity was present. Results: For the all stroke incidences, intensive-dose statin treatment compared with placebo treatment and standard-dose statin treatment compared with placebo treatment showed a significant 21% reduction in relative risk (RR) (RR 0.79, 95% confidence interval (CI) [0.71, 0.87], P statin treatment compared with standard dose or placebo was effective reducing fatal stroke (RR 0.61, 95% CI [0.39, 0.96], P = 0.03) and the RR was 1.01 (95% CI [0.85, 1.20], P = 0.90) in standard-dose statin treatment compared with placebo. Conclusion: The results of this meta-analysis suggest that intensive-dose statin treatment might be more favorable for reducing the incidences of all strokes than standard-dose statin treatment, especially for patients older than 65 years in reducing the incidences of all stroke incidences. PMID:27684837

  14. The Australian Commonwealth standard of measurement for absorbed radiation dose

    International Nuclear Information System (INIS)

    Sherlock, S.L.

    1990-06-01

    This report documents the absorbed dose standard for photon beams in the range from 1 to 25 MeV. Measurements of absorbed dose in graphite irradiated by a beam of cobalt-60 gamma rays from an Atomic Energy of Canada Limited (AECL) E1 Dorado 6 teletherapy unit are reported. The measurements were performed using a graphite calorimeter, which is the primary standard for absorbed dose. The measurements are used to calibrate a working standard ion chamber in terms of absorbed dose in graphite. Details of the methods, results and correction factors applied are given in Appendices. 13 refs., 6 tabs., 6 figs

  15. Clinical impact of electron density calibration on dose calculation

    International Nuclear Information System (INIS)

    Fisher, S. T.; Bromley, R.; Oliver, L.D.

    2011-01-01

    Full text: 3D calculation of dose for radiotherapy planning requires accurate density data in the form of Hounsfield Units (HU) obtained from CT scans. This investigation aims to establish the clinical impact that inaccuracies in the definition of the relationship between HU and electron density may have on the dose distribution for a range of treatment sites. HU versus electron density calibration relationships were derived from RMI 465, Catphan and CTRS phantoms scanned on a GE Lightspeed RT CT. Dose calculations were performed using Eclipse AAA 8.6.14. A range of patient case studies were assessed in terms of reference point doses, off axis dose points, dose subtraction plots and dose volume histograms. The RMI electron density calibration was regarded as the gold standard. All plans used identical field parameters, monitor units and optimal fluence maps derived from the RMI reference plan to enable direct dosimetric comparison. Plans calculated with the CIRS and RMI electron density calibrations were comparable. In contrast, the electron density calibration derived from Catphan produced dose differences in the order of 8% for head and neck, 6% for pelvis and 2% for a simple spine case. Incorrect electron density calibration data can result in significant dosimetric error and should be validated against a gold standard prior to implementation in a TPS.

  16. Measuring pacemaker dose: A clinical perspective

    Energy Technology Data Exchange (ETDEWEB)

    Studenski, Matthew T., E-mail: matthew.studenski@jeffersonhospital.org [Department of Radiation Oncology at the Jefferson Medical College and Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA (United States); Xiao Ying; Harrison, Amy S. [Department of Radiation Oncology at the Jefferson Medical College and Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA (United States)

    2012-07-01

    Recently in our clinic, we have seen an increased number of patients presenting with pacemakers and defibrillators. Precautions are taken to develop a treatment plan that minimizes the dose to the pacemaker because of the adverse effects of radiation on the electronics. Here we analyze different dosimeters to determine which is the most accurate in measuring pacemaker or defibrillator dose while at the same time not requiring a significant investment in time to maintain an efficient workflow in the clinic. The dosimeters analyzed here were ion chambers, diodes, metal-oxide-semiconductor field effect transistor (MOSFETs), and optically stimulated luminescence (OSL) dosimeters. A simple phantom was used to quantify the angular and energy dependence of each dosimeter. Next, 8 patients plans were delivered to a Rando phantom with all the dosimeters located where the pacemaker would be, and the measurements were compared with the predicted dose. A cone beam computed tomography (CBCT) image was obtained to determine the dosimeter response in the kilovoltage energy range. In terms of the angular and energy dependence of the dosimeters, the ion chamber and diode were the most stable. For the clinical cases, all the dosimeters match relatively well with the predicted dose, although the ideal dosimeter to use is case dependent. The dosimeters, especially the MOSFETS, tend to be less accurate for the plans, with many lateral beams. Because of their efficiency, we recommend using a MOSFET or a diode to measure the dose. If a discrepancy is observed between the measured and expected dose (especially when the pacemaker to field edge is <10 cm), we recommend analyzing the treatment plan to see whether there are many lateral beams. Follow-up with another dosimeter rather than repeating multiple times with the same type of dosimeter. All dosimeters should be placed after the CBCT has been acquired.

  17. Raising standards in clinical research

    DEFF Research Database (Denmark)

    Ohmann, C.; Canham, S.; Demotes, J.

    2017-01-01

    The nature and the purpose of the ECRIN Data Centre Certification Programme are summarised, and a very brief description is given of the underlying standards (129 in total, divided into 19 separate lists). The certification activity performed so far is described. In a pilot phase 2 centres were c...

  18. Standard and trace-dose lithium: a systematic review of dementia prevention and other behavioral benefits.

    Science.gov (United States)

    Mauer, Sivan; Vergne, Derick; Ghaemi, S Nassir

    2014-09-01

    Dementia is a major public health issue, with notably high rates in persons with mood illnesses. Lithium has been shown to have considerable neuroprotective effects, even in trace or low doses. The aim of this review is to summarize the current understanding of lithium benefits in trace or low doses in dementia prevention and for other behavioral or medical benefits. A systematic review identified 24 clinical, epidemiological, and biological reports that met inclusion criteria of assessing lithium in standard or low doses for dementia or other behavioral or medical benefits. Five out of seven epidemiological studies found an association between standard-dose lithium and low dementia rates. Nine out of 11 epidemiological studies, usually of drinking water sources, found an association between trace-dose lithium and low suicide/homicide/mortality and crime rates. All four small randomized clinical trials of lithium for Alzheimer's dementia have found at least some clinical or biological benefits versus placebo. Only one small randomized clinical trial (RCT) of trace lithium has been conducted, assessing mood symptoms in former substance abusers, and found benefit with lithium versus placebo. Lithium, in both standard and trace doses, appears to have biological benefits for dementia, suicide, and other behavioral outcomes. Further RCT research of trace lithium in dementia is warranted. © The Royal Australian and New Zealand College of Psychiatrists 2014.

  19. Effect of Tailored Dose-Dense Chemotherapy vs Standard 3-Weekly Adjuvant Chemotherapy on Recurrence-Free Survival Among Women With High-Risk Early Breast Cancer: A Randomized Clinical Trial.

    Science.gov (United States)

    Foukakis, Theodoros; von Minckwitz, Gunter; Bengtsson, Nils-Olof; Brandberg, Yvonne; Wallberg, Birgitta; Fornander, Tommy; Mlineritsch, Brigitte; Schmatloch, Sabine; Singer, Christian F; Steger, Günther; Egle, Daniel; Karlsson, Eva; Carlsson, Lena; Loibl, Sibylle; Untch, Michael; Hellström, Mats; Johansson, Hemming; Anderson, Harald; Malmström, Per; Gnant, Michael; Greil, Richard; Möbus, Volker; Bergh, Jonas

    2016-11-08

    Standard dosing of chemotherapy based on body surface area results in marked interpatient variation in pharmacokinetics, toxic effects, and efficacy. Whether tailored dosing can improve outcomes is unknown, as is the role of dose-dense adjuvant chemotherapy. To determine whether tailored dose-dense adjuvant chemotherapy improves the outcomes of early breast cancer compared with a standard 3-weekly chemotherapy schedule. A randomized, open-label, phase 3 trial of women aged 65 years and younger who had surgery for nonmetastatic node-positive or high-risk node-negative breast cancer at 86 sites in Sweden, Germany, and Austria between February 20, 2007, and September 14, 2011. Patients were randomized 1:1 either to 4 cycles of leukocyte nadir-based tailored and dose-dense adjuvant epirubicin and cyclophosphamide every 2 weeks followed by 4 cycles of tailored dose-dense docetaxel every 2 weeks, or to standard-interval chemotherapy with 3 cycles of fluorouracil and epirubicin-cyclophosphamide every 3 weeks followed by 3 cycles of docetaxel every 3 weeks. The primary end point was breast cancer recurrence-free survival (BCRFS). Secondary end points included 5-year event-free survival (EFS), distant disease-free survival (DDFS), overall survival (OS), and rates of grade 3 or 4 toxic effects. Among 2017 randomized patients (1006 in the tailored dose-dense group and 1011 in the control group; median [IQR] age, 51 [45-58] years; 80% with hormone receptor-positive tumors; 97% with node-positive disease), 2000 received study treatment (≥1 cycle of chemotherapy; 1001 in the tailored dose-dense group and 999 in the control group). After a median follow-up of 5.3 years (IQR, 4.5-6.1 years), 269 BCRFS events were reported, 118 in the tailored dose-dense group and 151 in the control group (HR, 0.79; 95% CI, 0.61-1.01; log-rank P = .06; 5-year BCRFS, 88.7% vs 85.0%). The tailored dose-dense group had significantly better EFS than the control group (HR, 0.79; 95% CI, 0

  20. Standards for Clinical Grade Genomic Databases.

    Science.gov (United States)

    Yohe, Sophia L; Carter, Alexis B; Pfeifer, John D; Crawford, James M; Cushman-Vokoun, Allison; Caughron, Samuel; Leonard, Debra G B

    2015-11-01

    Next-generation sequencing performed in a clinical environment must meet clinical standards, which requires reproducibility of all aspects of the testing. Clinical-grade genomic databases (CGGDs) are required to classify a variant and to assist in the professional interpretation of clinical next-generation sequencing. Applying quality laboratory standards to the reference databases used for sequence-variant interpretation presents a new challenge for validation and curation. To define CGGD and the categories of information contained in CGGDs and to frame recommendations for the structure and use of these databases in clinical patient care. Members of the College of American Pathologists Personalized Health Care Committee reviewed the literature and existing state of genomic databases and developed a framework for guiding CGGD development in the future. Clinical-grade genomic databases may provide different types of information. This work group defined 3 layers of information in CGGDs: clinical genomic variant repositories, genomic medical data repositories, and genomic medicine evidence databases. The layers are differentiated by the types of genomic and medical information contained and the utility in assisting with clinical interpretation of genomic variants. Clinical-grade genomic databases must meet specific standards regarding submission, curation, and retrieval of data, as well as the maintenance of privacy and security. These organizing principles for CGGDs should serve as a foundation for future development of specific standards that support the use of such databases for patient care.

  1. A new low-dose CT examination compared with standard-dose CT in the diagnosis of acute sinusitis

    Energy Technology Data Exchange (ETDEWEB)

    Hagtvedt, T.; Aaloekken, T.M.; Noetthellen, J.; Kolbenstvedt, A. [Department of Radiology, Rikshospitalet, 0027 Oslo (Norway)

    2003-05-01

    A low-dose CT of the paranasal sinuses was designed with few, thin sections, non-uniform intersection gaps, low milliampere settings and avoidance of direct radiation to the eye lens. The low-dose CT was prospectively compared with standard-dose CT in patients with suspicion of acute sinusitis. Forty-seven patients were examined with low-dose CT immediately after standard-dose CT. The effective dose and the lens dose were calculated and compared. Using standard-dose CT as a gold standard the sensitivity and specificity of low-dose CT was calculated for each sinus group. The effective dose and the lens dose of the low-dose CT were reduced to, respectively, 3 and 2% of the standard-dose CT. The diagnostic yield of the low-dose CT with regard to acute sinusitis was good with a high specificity ({>=}96%) for all sinus groups. The sensitivity was also high ({>=}95%) except for the frontal sinus where the sensitivity was 83%. Low-dose CT offers considerable dose reduction and should be the standard for imaging patients with suspected acute inflammatory paranasal disease. (orig.)

  2. Status of air kerma and absorbed dose standards in India

    International Nuclear Information System (INIS)

    Vijayam, M.; Ramanathan, G.; Patki, V.S.; Soman, A.T.; Shigwan, J.B.; Vinatha, S.P.; Jadhavgaonkar, P.S.; Kadam, V.D.; Shaha, V.V.; Abani, M.C.

    2002-01-01

    -volumes are maintained as primary standards for protection level and brachytherapy measurements of Ir-192, Cs-137 and Co-60 sources. These chambers are made of high purity reactor-grade graphite of density 1700 kg/m 3 . The three chambers have different wall thickness, the external diameters of all the chambers being equal. A reference standard in the form of a re-entrant chamber developed at BARC, calibrated against this primary standard was intercompared with a reference standard from M.D Anderson Centre, Houston, U.S.A and the results showed a good agreement. Recently one of the chambers was used for the Cs-137 intercomparison with IAEA and showed an agreement of better than ± 1%. 3. Primary Standard for X-rays - the free air chamber (FAC): This facility is utilized in conjunction with a Philips RT-250 X-ray machine for calibrating secondary standard dosemeters at different X-ray qualities in the 75 to 250 kV range. The total uncertainty in the realization of air kerma is around ±1% using the free air chamber. Accuracy of calibration of the secondary standards is estimated to be better than ±2%. The FAC has been intercompared via transferable transfer standards with FACs at BIPM (1971), BNM (France) RCL (Canada) and Kriss (Korea), which showed good agreement within ±1% after necessary correction for the spectral differences in X-ray beams. BARC is just now taking part in intercomparisons of X-ray air kerma calibration factors organised by Institute of Nuclear Energy Research (INER), Taiwan under Asia Pacific Metrology Programme. In addition to the above-mentioned primary standards, the SSDL is also maintaining the following secondary standards. For air kerma measurements at Co-60 gamma energy, ionisation chambers of Exradin A3, NE2571, NE2577 and Victoreen 415 types are calibrated and maintained. For Co-60 radiation dose to water measurements, NE 2571 and NE 2577 chambers calibrated at BIPM in terms of N D,W are maintained. For air kerma at medium energy x

  3. Prediction of standard-dose brain PET image by using MRI and low-dose brain [{sup 18}F]FDG PET images

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Jiayin [School of Electronics Engineering, Huaihai Institute of Technology, Lianyungang, Jiangsu 222005, China and IDEA Laboratory, Department of Radiology and BRIC, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599 (United States); Gao, Yaozong [IDEA Laboratory, Department of Radiology and BRIC, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599 and Department of Computer Science, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599 (United States); Shi, Feng [IDEA Laboratory, Department of Radiology and BRIC, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599 (United States); Lalush, David S. [Joint UNC-NCSU Department of Biomedical Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States); Lin, Weili [MRI Laboratory, Department of Radiology and BRIC, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599 (United States); Shen, Dinggang, E-mail: dgshen@med.unc.edu [IDEA Laboratory, Department of Radiology and BRIC, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599 and Department of Brain and Cognitive Engineering, Korea University, Seoul 136-713 (Korea, Republic of)

    2015-09-15

    Purpose: Positron emission tomography (PET) is a nuclear medical imaging technology that produces 3D images reflecting tissue metabolic activity in human body. PET has been widely used in various clinical applications, such as in diagnosis of brain disorders. High-quality PET images play an essential role in diagnosing brain diseases/disorders. In practice, in order to obtain high-quality PET images, a standard-dose radionuclide (tracer) needs to be used and injected into a living body. As a result, it will inevitably increase the patient’s exposure to radiation. One solution to solve this problem is predicting standard-dose PET images using low-dose PET images. As yet, no previous studies with this approach have been reported. Accordingly, in this paper, the authors propose a regression forest based framework for predicting a standard-dose brain [{sup 18}F]FDG PET image by using a low-dose brain [{sup 18}F]FDG PET image and its corresponding magnetic resonance imaging (MRI) image. Methods: The authors employ a regression forest for predicting the standard-dose brain [{sup 18}F]FDG PET image by low-dose brain [{sup 18}F]FDG PET and MRI images. Specifically, the proposed method consists of two main steps. First, based on the segmented brain tissues (i.e., cerebrospinal fluid, gray matter, and white matter) in the MRI image, the authors extract features for each patch in the brain image from both low-dose PET and MRI images to build tissue-specific models that can be used to initially predict standard-dose brain [{sup 18}F]FDG PET images. Second, an iterative refinement strategy, via estimating the predicted image difference, is used to further improve the prediction accuracy. Results: The authors evaluated their algorithm on a brain dataset, consisting of 11 subjects with MRI, low-dose PET, and standard-dose PET images, using leave-one-out cross-validations. The proposed algorithm gives promising results with well-estimated standard-dose brain [{sup 18}F]FDG PET

  4. Prediction of standard-dose brain PET image by using MRI and low-dose brain [18F]FDG PET images

    International Nuclear Information System (INIS)

    Kang, Jiayin; Gao, Yaozong; Shi, Feng; Lalush, David S.; Lin, Weili; Shen, Dinggang

    2015-01-01

    Purpose: Positron emission tomography (PET) is a nuclear medical imaging technology that produces 3D images reflecting tissue metabolic activity in human body. PET has been widely used in various clinical applications, such as in diagnosis of brain disorders. High-quality PET images play an essential role in diagnosing brain diseases/disorders. In practice, in order to obtain high-quality PET images, a standard-dose radionuclide (tracer) needs to be used and injected into a living body. As a result, it will inevitably increase the patient’s exposure to radiation. One solution to solve this problem is predicting standard-dose PET images using low-dose PET images. As yet, no previous studies with this approach have been reported. Accordingly, in this paper, the authors propose a regression forest based framework for predicting a standard-dose brain [ 18 F]FDG PET image by using a low-dose brain [ 18 F]FDG PET image and its corresponding magnetic resonance imaging (MRI) image. Methods: The authors employ a regression forest for predicting the standard-dose brain [ 18 F]FDG PET image by low-dose brain [ 18 F]FDG PET and MRI images. Specifically, the proposed method consists of two main steps. First, based on the segmented brain tissues (i.e., cerebrospinal fluid, gray matter, and white matter) in the MRI image, the authors extract features for each patch in the brain image from both low-dose PET and MRI images to build tissue-specific models that can be used to initially predict standard-dose brain [ 18 F]FDG PET images. Second, an iterative refinement strategy, via estimating the predicted image difference, is used to further improve the prediction accuracy. Results: The authors evaluated their algorithm on a brain dataset, consisting of 11 subjects with MRI, low-dose PET, and standard-dose PET images, using leave-one-out cross-validations. The proposed algorithm gives promising results with well-estimated standard-dose brain [ 18 F]FDG PET image and substantially

  5. Emphysema quantification and lung volumetry in chest X-ray equivalent ultralow dose CT - Intra-individual comparison with standard dose CT.

    Science.gov (United States)

    Messerli, Michael; Ottilinger, Thorsten; Warschkow, René; Leschka, Sebastian; Alkadhi, Hatem; Wildermuth, Simon; Bauer, Ralf W

    2017-06-01

    To determine whether ultralow dose chest CT with tin filtration can be used for emphysema quantification and lung volumetry and to assess differences in emphysema measurements and lung volume between standard dose and ultralow dose CT scans using advanced modeled iterative reconstruction (ADMIRE). 84 consecutive patients from a prospective, IRB-approved single-center study were included and underwent clinically indicated standard dose chest CT (1.7±0.6mSv) and additional single-energy ultralow dose CT (0.14±0.01mSv) at 100kV and fixed tube current at 70mAs with tin filtration in the same session. Forty of the 84 patients (48%) had no emphysema, 44 (52%) had emphysema. One radiologist performed fully automated software-based pulmonary emphysema quantification and lung volumetry of standard and ultralow dose CT with different levels of ADMIRE. Friedman test and Wilcoxon rank sum test were used for multiple comparison of emphysema and lung volume. Lung volumes were compared using the concordance correlation coefficient. The median low-attenuation areas (LAA) using filtered back projection (FBP) in standard dose was 4.4% and decreased to 2.6%, 2.1% and 1.8% using ADMIRE 3, 4, and 5, respectively. The median values of LAA in ultralow dose CT were 5.7%, 4.1% and 2.4% for ADMIRE 3, 4, and 5, respectively. There was no statistically significant difference between LAA in standard dose CT using FBP and ultralow dose using ADMIRE 4 (p=0.358) as well as in standard dose CT using ADMIRE 3 and ultralow dose using ADMIRE 5 (p=0.966). In comparison with standard dose FBP the concordance correlation coefficients of lung volumetry were 1.000, 0.999, and 0.999 for ADMIRE 3, 4, and 5 in standard dose, and 0.972 for ADMIRE 3, 4 and 5 in ultralow dose CT. Ultralow dose CT at chest X-ray equivalent dose levels allows for lung volumetry as well as detection and quantification of emphysema. However, longitudinal emphysema analyses should be performed with the same scan protocol and

  6. Standardized training in nurse model travel clinics.

    Science.gov (United States)

    Sofarelli, Theresa A; Ricks, Jane H; Anand, Rahul; Hale, Devon C

    2011-01-01

    International travel plays a significant role in the emergence and redistribution of major human diseases. The importance of travel medicine clinics for preventing morbidity and mortality has been increasingly appreciated, although few studies have thus far examined the management and staff training strategies that result in successful travel-clinic operations. Here, we describe an example of travel-clinic operation and management coordinated through the University of Utah School of Medicine, Division of Infectious Diseases. This program, which involves eight separate clinics distributed statewide, functions both to provide patient consult and care services, as well as medical provider training and continuing medical education (CME). Initial training, the use of standardized forms and protocols, routine chart reviews and monthly continuing education meetings are the distinguishing attributes of this program. An Infectious Disease team consisting of one medical doctor (MD) and a physician assistant (PA) act as consultants to travel nurses who comprise the majority of clinic staff. Eight clinics distributed throughout the state of Utah serve approximately 6,000 travelers a year. Pre-travel medical services are provided by 11 nurses, including 10 registered nurses (RNs) and 1 licensed practical nurse (LPN). This trained nursing staff receives continuing travel medical education and participate in the training of new providers. All nurses have completed a full training program and 7 of the 11 (64%) of clinic nursing staff serve more than 10 patients a week. Quality assurance measures show that approximately 0.5% of charts reviewed contain a vaccine or prescription error which require patient notification for correction. Using an initial training program, standardized patient intake forms, vaccine and prescription protocols, preprinted prescriptions, and regular CME, highly trained nurses at travel clinics are able to provide standardized pre-travel care to

  7. High versus standard dose caffeine for apnoea: a systematic review.

    Science.gov (United States)

    Vliegenthart, Roos; Miedema, Martijn; Hutten, Gerard J; van Kaam, Anton H; Onland, Wes

    2018-02-07

    Placebo-controlled trials have shown that caffeine is highly effective in treating apnoea of prematurity and reduces the risk of bronchopulmonary dysplasia (BPD) and neurodevelopmental impairment (NDI). To identify, appraise and summarise studies investigating the modulating effect of different caffeine dosages. A systematic review identified all randomised controlled trials (RCTs) comparing a high versus a standard caffeine treatment regimen in infants with a gestational age <32 weeks, by searching the main electronic databases and abstracts of the Pediatric Academic Societies. Studies comparing caffeine to placebo or theophylline only were excluded. Primary outcomes were BPD and mortality at 36 weeks postmenstrual age. Secondary key-outcome was neurodevelopmental outcome at 12 and 24 months corrected age. Meta-analysis was performed using RevMan 5.3. Six RCTs including 620 infants were identified. Meta-analysis showed a significant decrease in BPD, the combined outcome BPD or mortality, and failure to extubate in infants allocated to a higher caffeine dose. No differences were found in mortality alone and NDI. The quality of the outcome measures were deemed low to very low according to the Grading of Recommendations Assessment, Development and Evaluation guidelines. Although this review suggests that administering a higher dose of caffeine might enhance its beneficial effect on death or BPD, firm recommendations on the optimal caffeine dose cannot be given due to the low level of evidence. A large RCT is urgently needed to confirm or refute these findings and determine the optimal dose of caffeine. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  8. Short-course aminoglycoside therapy in patients with spinal cord injury. Standard dose versus low dose.

    Science.gov (United States)

    Sapico, F L; Lindquist, L B; Montgomerie, J Z; Jimenez, E M; Morrow, J W

    1980-05-01

    Twenty-nine patients with spinal cord injury and asymptomatic urinary tract infection were treated with standard or reduced doses of tobramycin and amikacin. The patients received five days of intramuscular antibiotics. Most of the patients in the tobramycin groups had Pseudomonas aeruginosa infection and most of those in the amikacin group had either Proteus rettgeri or Providencia stuartii infections. Only 1 patient had a positive urine antibody coating test. High antibiotic concentrations were demonstrated in the urine of all patients during therapy. Urine cultures were obtained two and seven days after completion of therapy. Forty-eight per cent of the patients were cured, while 31 per cent showed persistence or relapse, and 21 per cent had reinfection with other bacteria. No significant differences in results were observed between the standard-dose and low-dose regimens and between the amikacin and tobramycin groups. The low success rate of the regimens used may indicate the need to evaluate alternative therapeutic regimens to treat urinary tract infections in this special group of patients.

  9. Comparison of passive and standard dosing of polycyclic aromatic hydrocarbons to the marine algae Phaeodactylum tricornutum

    DEFF Research Database (Denmark)

    Witt, G.; Niehus, N. C.; Konopka, K.

    2015-01-01

    dosing according to the standard marine algae test procedure on microtiter plates. A comparison of the EC50 values of passive dosing vs. EC50 values of standard dosing showed an underestimation of the effects when using nominal standard dosing probably due to sorption, evaporation and limiting....... Passive dosing is a practical and economical way of improving the exposure of HOCs in aquatic toxicity or bioconcentration tests like the algae growth inhibition test. \

  10. Creation and clinical application of real-time dose monitor using dose area product meter

    International Nuclear Information System (INIS)

    Matsubara, Kosuke; Uoyama, Yoshinori; Iida, Hiroji; Mizushima, Takashi

    2004-01-01

    The management of patient dose has become more of an issue in recent years. Dose can be determined non-invasively and in real time through the use of a dose area product meter, but it is the area dose value that is obtained. Therefore, we created a program that estimates entrance skin dose (ESD) in real time from area dose values obtained during procedures. We used Microsoft Visual C++ 6.0 (Standard Edition) for the programming language and C language for the programming environment. The value was a maximum 285.4 mGy at ileus tube insertion when measuring ESD for radiography of the digestive organ and non-vascular type interventional radiology (IVR) using the created program and seeking the average according to the procedures. The program that we created can be considered valid for monitoring ESD correctly and in real time. (author)

  11. Analysis of uncertainties in the measurements of absorbed dose to water in a secondary standard dosimetry laboratory (SSDL) 60Cobalt

    International Nuclear Information System (INIS)

    Silva, Cosme Norival Mello da; Rosado, Paulo Henrique Goncalves

    2011-01-01

    The National Metrology Laboratory of Ionizing Radiation (LNMRI) is the laboratory designated by INMETRO in the field of Metrology of ionizing radiation and is a Secondary Standard Dosimetry Laboratory (SSDL). One of its guidelines is to maintain and disseminate LNMRI absorbed dose in water used as a national standard dosimetry in radiotherapy. For this pattern is metrologically acceptable accuracy and uncertainties should be assessed over time. The objective of this study is to analyze the uncertainties involved in determining the absorbed dose rate in water and standard uncertainty of absorbed dose calibration in water from a clinical dosimeter. The largest sources of uncertainty in determining the rate of absorbed dose in water are due to: calibration coefficient of the calibration certificate supplied by the BIPM, electrometer calibration, camber stability over time, variation of pressure and humidity, strong dependence and non-uniformity of the field. The expanded uncertainty is 0.94% for k = 2. For the calibration standard uncertainty of absorbed dose in water of a dosimeter in a clinical a major source of uncertainty is due to the absorbed dose rate in water (0.94%). The value of expanded uncertainty of calibrating a clinical dosimeter is 1.2% for k = 2. (author)

  12. Standard concentration infusions in paediatric intensive care: the clinical approach.

    Science.gov (United States)

    Perkins, Joanne; Aguado-Lorenzo, Virginia; Arenas-Lopez, Sara

    2017-05-01

    The use of standard concentrations of intravenous infusions has been advocated by international organisations to increase intravenous medication safety in paediatric and neonatal critical care. However, there is no guidance on how to identify and implement these infusions leading to great interunit variability. To identify the most appropriate clinical concentrations required by our paediatric intensive care unit (PICU) population with regard to accuracy of delivery and overall fluid allowance. Firstly a matrix was used to balance the concentration, dose and infusion volume (weight range 1.5-50 kg). Results were further refined considering: patient fluid allowance based on fluid volume targets, infusion pump accuracy and challenging each infusion against clinical scenarios requiring administration of multiple drug infusions found in PICU. Consideration was given to the standard concentrations routinely used in adults, in order to assess whether alignment with paediatrics was possible for some of the concentrations proposed. Finally a risk assessment of the infusions was conducted using the NPSA 20 tool. Twenty-five drugs identified as the most commonly used intravenous infusions in the unit. For the majority of the medicines, three weight bands of standard concentrations were necessary to cover the children's weight ranges and kept within predefined fluid requirements and accuracy of delivery. This work shows a patient focused systematic approach for defining and evaluating standardised concentrations in intensive care children. © 2016 Royal Pharmaceutical Society.

  13. Accuracy of low dose CT in the diagnosis of appendicitis in childhood and comparison with USG and standard dose CT.

    Science.gov (United States)

    Yi, Dae Yong; Lee, Kyung Hoon; Park, Sung Bin; Kim, Jee Taek; Lee, Na Mi; Kim, Hyery; Yun, Sin Weon; Chae, Soo Ahn; Lim, In Seok

    Computed tomography should be performed after careful consideration due to radiation hazard, which is why interest in low dose CT has increased recently in acute appendicitis. Previous studies have been performed in adult and adolescents populations, but no studies have reported on the efficacy of using low-dose CT in children younger than 10 years. Patients (n=475) younger than 10 years who were examined for acute appendicitis were recruited. Subjects were divided into three groups according to the examinations performed: low-dose CT, ultrasonography, and standard-dose CT. Subjects were categorized according to age and body mass index (BMI). Low-dose CT was a contributive tool in diagnosing appendicitis, and it was an adequate method, when compared with ultrasonography and standard-dose CT in terms of sensitivity (95.5% vs. 95.0% and 94.5%, p=0.794), specificity (94.9% vs. 80.0% and 98.8%, p=0.024), positive-predictive value (96.4% vs. 92.7% and 97.2%, p=0.019), and negative-predictive value (93.7% vs. 85.7% and 91.3%, p=0.890). Low-dose CT accurately diagnosed patients with a perforated appendix. Acute appendicitis was effectively diagnosed using low-dose CT in both early and middle childhood. BMI did not influence the accuracy of detecting acute appendicitis on low-dose CT. Low-dose CT is effective and accurate for diagnosing acute appendicitis in childhood, as well as in adolescents and young adults. Additionally, low-dose CT was relatively accurate, irrespective of age or BMI, for detecting acute appendicitis. Therefore, low-dose CT is recommended for assessing children with suspected acute appendicitis. Copyright © 2017. Published by Elsevier Editora Ltda.

  14. Standardization of image quality and radiation dose in mammography

    International Nuclear Information System (INIS)

    Hendrick, R.E.

    1990-01-01

    Image quality is the cornerstone to the practice of high-quality mammography. To ensure high quality in the practice of mammography, the American College of Radiology has established a voluntary program for the accreditation of mammographic screening sites. Between August 15, 1987, and February 1, 1989, 647 mammography units completed the accreditation program. Data collected from those units are presented, demonstrating that broad ranges of image quality and dose currently exist among mammographic screening sites. Reasons are discussed for the wide ranges observed, and steps are proposed to narrow the ranges of image quality and dose in the practice of mammography

  15. Individual versus standard dose of rFSH in a mild stimulation protocol for intrauterine insemination: a randomized study

    DEFF Research Database (Denmark)

    la Cour Freiesleben, N; Lossl, K; Bogstad, J

    2009-01-01

    -stimulating hormone (rFSH) dosage nomogram. The nomogram has now been tested. METHODS: Multicentre randomized controlled trial (RCT) including 228 ovulatory patients scheduled for COS and IUI. Patients were randomized to 'individual' (50-100 IU rFSH/day, n = 113) or 'standard' (75 IU rFSH/day, n = 115) dose......' group and 21/115 (18%) in the 'standard' group and the rate of multiple gestations was 1/113 (1%) versus 5/115 (4%), P = 0.21. CONCLUSIONS: This RCT is the first to clinically test a dosage nomogram in ovulatory IUI patients' first rFSH treatment cycle. Dosing according to the nomogram was superior...

  16. Comparative effectiveness of high-dose versus standard-dose influenza vaccination on numbers of US nursing home residents admitted to hospital: a cluster-randomised trial.

    Science.gov (United States)

    Gravenstein, Stefan; Davidson, H Edward; Taljaard, Monica; Ogarek, Jessica; Gozalo, Pedro; Han, Lisa; Mor, Vincent

    2017-09-01

    Immune responses to influenza vaccines decline with age, reducing clinical effectiveness. We compared the effect of the more immunogenic high-dose trivalent influenza vaccine with a standard-dose vaccine to identify the effect on reducing hospital admissions of nursing home residents in the USA. We did a single-blind, pragmatic, comparative effectiveness, cluster-randomised trial with a 2 × 2 factorial design. Medicare-certified nursing homes in the USA located within 50 miles of a Centers for Disease Control and Prevention influenza reporting city were recruited, so long as the facilities were not located in a hospital, had more than 50 long-stay residents, had less than 20% of the population aged under 65 years, and were not already planning to administer the high-dose influenza vaccine to residents. Enrolled nursing homes were randomised to a facility-wide standard of care for the residents of either high dose or standard dose as the vaccine for the 2013-14 influenza season and half of each group were randomly allocated to free vaccines for staff. Individual residents were included in the analysis group if they were aged 65 years or older and were long-stay residents (ie, had been in the facility 90 days or more before commencing the influenza vaccination programme). The analysts and investigators with access to the raw data were masked to study group by coding the groups until after the analyses were complete. The primary outcome was hospital admissions related to pulmonary and influenza-like illness between Nov 1, 2013, and May 31, 2014, identified from Medicare hospital claims available for residents who were without private health insurance (ie, those who were considered Medicare fee-for-service). We obtained data from the Centers for Medicare & Medicaid Services (CMS) and enrolled facilities. The analyses used marginal Poisson and Cox proportional hazards regression, accounting for clustering of residents within homes, on an intention-to-treat basis

  17. Standard dosing of piperacillin and meropenem fail to achieve adequate plasma concentrations in ICU patients.

    Science.gov (United States)

    Petersson, J; Giske, C G; Eliasson, E

    2016-11-01

    Controversies remain regarding optimal dosing and the need for plasma concentration measurements when treating intensive care patients with beta-lactam antibiotics. We studied ICU patients treated with either antibiotic, excluding patients on renal replacement therapy. Antibiotic concentrations were measured at the mid and end of the dosing interval, and repeated after 2-3 days when feasible. Glomerular filtration rate (GFR) was estimated from plasma creatinine and cystatin C, GFR calculated from cystatin C (eGFR) and measured creatinine clearance (CrCl). Measured concentrations were compared to the clinical susceptible breakpoints for Pseudomonas aeruginosa, 16 and 2 mg/l for piperacillin and meropenem respectively. We analysed 33 and 31 paired samples from 20 and 19 patients treated with piperacillin-tazobactam and meropenem respectively. Antibiotic concentrations at the mid and end of the dosing interval were for piperacillin, 27.0 (14.7-52.9) and 8.6 (2.7-30.3); and for meropenem, 7.5 (4.7-10.2) and 2.4 (1.0-3.5). All values median (interquartile range) and concentrations in mg/l. The percentage of measured concentrations below the breakpoint at the mid and end of the dosing interval were for piperacillin, 27% and 61%; and for meropenem, 6% and 48%. Lower estimates of GFR were associated with higher concentrations but concentrations varied greatly between patients with similar GFR. The correlation with terminal concentration half-life was similar for eGFR and CrCl. With standard doses of meropenem and piperacillin-tazobactam, plasma concentrations in ICU patients vary > 10-fold and are suboptimal in a significant percentage of patients. The variation is large also between patients with similar renal function. © 2016 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  18. 42 CFR 493.1457 - Standard; Clinical consultant responsibilities.

    Science.gov (United States)

    2010-10-01

    ... HUMAN SERVICES (CONTINUED) STANDARDS AND CERTIFICATION LABORATORY REQUIREMENTS Personnel for Nonwaived Testing Laboratories Performing High Complexity Testing § 493.1457 Standard; Clinical consultant... 42 Public Health 5 2010-10-01 2010-10-01 false Standard; Clinical consultant responsibilities. 493...

  19. Assessment of the occupational eye lens dose for clinical staff in interventional radiology, cardiology and neuroradiology.

    Science.gov (United States)

    Omar, Artur; Kadesjö, Nils; Palmgren, Charlotta; Marteinsdottir, Maria; Segerdahl, Tony; Fransson, Annette

    2017-03-20

    In accordance with recommendations by the International Commission on Radiological Protection, the current European Basic Safety Standards has adopted a reduced occupational eye lens dose limit of 20 mSv yr -1 . The radiation safety implications of this dose limit is of concern for clinical staff that work with relatively high dose x-ray angiography and interventional radiology. Presented in this work is a thorough assessment of the occupational eye lens dose based on clinical measurements with active personal dosimeters worn by staff during various types of procedures in interventional radiology, cardiology and neuroradiology. Results are presented in terms of the estimated equivalent eye lens dose for various medical professions. In order to compare the risk of exceeding the regulatory annual eye lens dose limit for the widely different clinical situations investigated in this work, the different medical professions were separated into categories based on their distinct work pattern: staff that work (a) regularly beside the patient, (b) in proximity to the patient and (c) typically at a distance from the patient. The results demonstrate that the risk of exceeding the annual eye lens dose limit is of concern for staff category (a), i.e. mainly the primary radiologist/cardiologist. However, the results also demonstrate that the risk can be greatly mitigated if radiation protection shields are used in the clinical routine. The results presented in this work cover a wide range of clinical situations, and can be used as a first indication of the risk of exceeding the annual eye lens dose limit for staff at other medical centres.

  20. 42 CFR 493.1417 - Standard; Clinical consultant qualifications.

    Science.gov (United States)

    2010-10-01

    ... Testing Laboratories Performing Moderate Complexity Testing § 493.1417 Standard; Clinical consultant qualifications. The clinical consultant must be qualified to consult with and render opinions to the laboratory's... 42 Public Health 5 2010-10-01 2010-10-01 false Standard; Clinical consultant qualifications. 493...

  1. 42 CFR 493.1419 - Standard; Clinical consultant responsibilities.

    Science.gov (United States)

    2010-10-01

    ... Testing Laboratories Performing Moderate Complexity Testing § 493.1419 Standard; Clinical consultant... clinical consultation to the laboratory's clients; (b) Be available to assist the laboratory's clients in... 42 Public Health 5 2010-10-01 2010-10-01 false Standard; Clinical consultant responsibilities. 493...

  2. 42 CFR 493.1455 - Standard; Clinical consultant qualifications.

    Science.gov (United States)

    2010-10-01

    ... Testing Laboratories Performing High Complexity Testing § 493.1455 Standard; Clinical consultant qualifications. The clinical consultant must be qualified to consult with and render opinions to the laboratory's... 42 Public Health 5 2010-10-01 2010-10-01 false Standard; Clinical consultant qualifications. 493...

  3. Comparison of the two different standard flux-to-dose rate conversion factors

    International Nuclear Information System (INIS)

    Metghalchi, M.; Ashrafi, R.

    1983-01-01

    A very useful and simple way of obtaining the dose rate associated with neutron or photon fluxes is to multiply these fluxes by the appropriate flux-to-dose rate conversion factors. Two basic standard flux-to-dose rate conversion factors. are being used in all over the world, those recommended by the International Commission on Radiation Protection (ICRP) and the American National Standars (ANS). The purpose of this paper is to compare these two standard with each other. The comparison proved that the dose rate associated with a specific neutron flux, obtained by the ANS flux-to-dose rate conversion factors is usually higher than those calculated by the ICRP's conversion factors. Whereas in the case of the photon, in all energies, the difference between the dose rates obtained by these two standard flux-to-dose rate conversion factors are noticeable, and the ANS results are higher than the ICRP ones. So, it should be noted that for a specific neutron or photon flux the dose rate obtained by the ANS flux-to-dose rate conversion factors are more conservative than those obtained by the ICRP's. Therefore, in order to establish a more reasonable new standard flux-to-dose rate conversion factors, more work should be done. (author)

  4. Thermal dose requirement for tissue effect: experimental and clinical findings

    Science.gov (United States)

    Dewhirst, Mark; Viglianti, Benjamin L.; Lora-Michiels, Michael; Hoopes, P. Jack; Hanson, Margaret A.

    2003-06-01

    In this review we have summarized the basic principles that govern the relationships between thermal exposure (temperature and time of exposure) and thermal damage, with an emphasis on normal tissue effects. We have also attempted to identify specific thermal dose information (for safety and injury) for a variety of tissues in a variety of species. We address the use, accuracy and difficulty of conversion of an individual time and temperature (thermal dose) to a standardized value (eg equivalent minutes at 43degC) for comparison of thermal treatments. Although, the conversion algorithm appears to work well within a range of moderately elevated temperatures (2-15degC) above normal physiologic baseline (37-39degC) there is concern that conversion accuracy does not hold up for temperatures which are minimally or significantly above baseline. An extensive review of the literature suggests a comprehensive assessment of the "thermal dose-to-tissue effect" has not previously been assembled for most individual tissues and never been viewed in a semi-comprehensive (tissues and species) manner. Finally, we have addressed the relationship of thermal dose-to-effect vs. baseline temperature. This issues is important since much of the thermal dose-to-effect information has been accrued in animal models with baseline temperatures 1-2 deg higher than that of humans.

  5. Reliability of dose volume constraint inference from clinical data

    DEFF Research Database (Denmark)

    Lutz, C M; Møller, D S; Hoffmann, L

    2017-01-01

    Dose volume histogram points (DVHPs) frequently serve as dose constraints in radiotherapy treatment planning. An experiment was designed to investigate the reliability of DVHP inference from clinical data for multiple cohort sizes and complication incidence rates. The experimental background...... was radiation pneumonitis in non-small cell lung cancer and the DVHP inference method was based on logistic regression. From 102 NSCLC real-life dose distributions and a postulated DVHP model, an 'ideal' cohort was generated where the most predictive model was equal to the postulated model. A bootstrap...... and a Cohort Replication Monte Carlo (CoRepMC) approach were applied to create 1000 equally sized populations each. The cohorts were then analyzed to establish inference frequency distributions. This was applied to nine scenarios for cohort sizes of 102 (1), 500 (2) to 2000 (3) patients (by sampling...

  6. A simple method for estimating the effective dose in dental CT. Conversion factors and calculation for a clinical low-dose protocol

    International Nuclear Information System (INIS)

    Homolka, P.; Kudler, H.; Nowotny, R.; Gahleitner, A.; Wien Univ.

    2001-01-01

    An easily appliable method to estimate effective dose including in its definition the high radio-sensitivity of the salivary glands from dental computed tomography is presented. Effective doses were calculated for a markedly dose reduced dental CT protocol as well as for standard settings. Data are compared with effective doses from the literature obtained with other modalities frequently used in dental care. Methods: Conversion factors based on the weighted Computed Tomography Dose Index were derived from published data to calculate effective dose values for various CT exposure settings. Results: Conversion factors determined can be used for clinically used kVp settings and prefiltrations. With reduced tube current an effective dose for a CT examination of the maxilla of 22 μSv can be achieved, which compares to values typically obtained with panoramic radiography (26 μSv). A CT scan of the mandible, respectively, gives 123 μSv comparable to a full mouth survey with intraoral films (150 μSv). Conclusion: For standard CT scan protocols of the mandible, effective doses exceed 600 μSv. Hence, low dose protocols for dental CT should be considered whenever feasable, especially for paediatric patients. If hard tissue diagnoses is performed, the potential of dose reduction is significant despite the higher image noise levels as readability is still adequate. (orig.) [de

  7. Quantitative comparison of low dose and standard dose radioiodine therapy effectiveness in patients with low risk differentiated thyroid cancer.

    Science.gov (United States)

    Abdulrezzak, Ummuhan; Tutus, Ahmet; Isik, Ilknur; Kurt, Yurdagul; Kula, Mustafa

    2017-09-01

    The aim of this paper was to compare the results of postoperative I-131 remnant ablation therapy using a quantitative data in the low activity (1110 MBq) and standard dose (3700 MBq). The study included two groups of patients with low risk differentiated thyroid cancer (DTC): Group L (low dose group) included 54 patients who were treated with 1110 MBq I-131 and Group S (standard dose group) included 61 patients treated with 3700 MBq. The postoperative thyroid remnants were assessed with the pretreatment thyroid uptake test (PTUT) and the whole body scans (WBS) were performed in the 7th day after the ablation treatment. We obtained the average count per pixel from the standard region of interest analysis of the thyroid bed (Tavc), liver (Lavc), thigh (Thavc) and whole body (WBkc). At the sixth month after the treatment, WBS were performed to 106 patients (45 patients from Group L and 61 patients from Group S) to evaluate the success of ablation treatment. A significant difference in PTUT and Tavc was not found between the two groups (P>0.05). However, Lavc, Thavc and WBkc were significantly higher in Group S compared with Group L (P0.05). In low risk DTC patients, low dose radioactive iodine can ablate thyroid remnants as effectively as a higher dose with less radiation exposure to other non-target organs and the whole body.

  8. Hormone-Balancing Effect of Pre-Gelatinized Organic Maca (Lepidium peruvianum Chacon): (II) Physiological and Symptomatic Responses of Early-Postmenopausal Women to Standardized doses of Maca in Double Blind, Randomized, Placebo-Controlled, Multi-Centre Clinical Study.

    Science.gov (United States)

    Meissner, H O; Mscisz, A; Reich-Bilinska, H; Kapczynski, W; Mrozikiewicz, P; Bobkiewicz-Kozlowska, T; Kedzia, B; Lowicka, A; Barchia, I

    2006-12-01

    This was a double-blind, randomized, placebo-corrected, outpatient, multi-centre (five sites) clinical study, in which a total of 168 Caucasian early-postmenopausal women volunteers (age>49 years) participated after fulfilling the criteria: follicle stimulating hormone (FSH) >30 IU/ml and estrogen (E2) Maca (Maca-GO) treatment, according to different monthly treatment sequences scheduled for each site. Two 500 mg vegetable hard gel capsules with Maca-GO or Placebo powder were self-administered twice daily with meals (total 2 g/day) during three (Trial I; n=102) or four (Trial II; n=66) months study periods. At the baseline and follow- up monthly intervals, blood levels of FSH, E2, progesterone (PRG) and lutinizing hormone (LH), as well as serum cholesterol (CHOL), triglycerides (TRG), high- and low density lipoproteins (HDL and LDL) were measured. Menopausal symptoms were assessed according to Greene's Score (GMS) and Kupperman's Index (KMI). Data were analyzed using multivariate technique on blocs of monthly results in one model and Maca versus Placebo contrast in another model. A total of 124 women concluded the study. Maca-GO significantly stimulated production of E2 (PMaca-GO significantly reduced both frequency and severity of individual menopausal symptoms (hot flushes and night sweating in particular) resulting in significant (P<0.001) alleviation of KMI (from 22 to 10), thus, offering an attractive non-hormonal addition to the choices available to early-postmenopausal women in the form of a natural plant alternative to Hormone Replacement Therapy (HRT) - hence, reducing dependence on hormone therapy programs.

  9. Trends and the determination of effective doses for standard X-ray procedures

    International Nuclear Information System (INIS)

    Johnson, H.M.; Neduzak, C.; Gallet, J.; Sandeman, J.

    2001-01-01

    Trends in the entrance skin exposures (air kerma) for standard x-ray imaging procedures are reported for the Province of Manitoba, Canada. Average annual data per procedure using standard phantoms and standard ion chambers have been recorded since 1981. For example, chest air kerma (backscatter included) has decreased from 0.14 to 0.09 mGy. Confounding factors may negate the gains unless facility quality control programs are maintained. The data were obtained for a quality assurance and regulatory compliance program. Quoting such data for risk evaluation purposes lacks rigor hence a compartment model for organ apportioning, using organ absorbed doses and weighting factors, has been applied to determine effective dose per procedure. The effective doses for the standard procedures are presented, including the value of 0.027 mSv (1999) calculated for the effective dose in PA chest imaging. (author)

  10. Effect of High-Dose vs Standard-Dose Wintertime Vitamin D Supplementation on Viral Upper Respiratory Tract Infections in Young Healthy Children.

    Science.gov (United States)

    Aglipay, Mary; Birken, Catherine S; Parkin, Patricia C; Loeb, Mark B; Thorpe, Kevin; Chen, Yang; Laupacis, Andreas; Mamdani, Muhammad; Macarthur, Colin; Hoch, Jeffrey S; Mazzulli, Tony; Maguire, Jonathon L

    2017-07-18

    Epidemiological studies support a link between low 25-hydroxyvitamin D levels and a higher risk of viral upper respiratory tract infections. However, whether winter supplementation of vitamin D reduces the risk among children is unknown. To determine whether high-dose vs standard-dose vitamin D supplementation reduces the incidence of wintertime upper respiratory tract infections in young children. A randomized clinical trial was conducted during the winter months between September 13, 2011, and June 30, 2015, among children aged 1 through 5 years enrolled in TARGet Kids!, a multisite primary care practice-based research network in Toronto, Ontario, Canada. Three hundred forty-nine participants were randomized to receive 2000 IU/d of vitamin D oral supplementation (high-dose group) vs 354 participants who were randomized to receive 400 IU/d (standard-dose group) for a minimum of 4 months between September and May. The primary outcome was the number of laboratory-confirmed viral upper respiratory tract infections based on parent-collected nasal swabs over the winter months. Secondary outcomes included the number of influenza infections, noninfluenza infections, parent-reported upper respiratory tract illnesses, time to first upper respiratory tract infection, and serum 25-hydroxyvitamin D levels at study termination. Among 703 participants who were randomized (mean age, 2.7 years, 57.7% boys), 699 (99.4%) completed the trial. The mean number of laboratory-confirmed upper respiratory tract infections per child was 1.05 (95% CI, 0.91-1.19) for the high-dose group and 1.03 (95% CI, 0.90-1.16) for the standard-dose group, for a between-group difference of 0.02 (95% CI, -0.17 to 0.21) per child. There was no statistically significant difference in number of laboratory-confirmed infections between groups (incidence rate ratio [RR], 0.97; 95% CI, 0.80-1.16). There was also no significant difference in the median time to the first laboratory-confirmed infection: 3.95 months

  11. Primary seroresponses to double-dose compared with standard-dose hepatitis B vaccination in patients with chronic kidney disease: a systematic review and meta-analysis.

    Science.gov (United States)

    Mulley, William R; Le, Suong T T; Ives, Kathryn E

    2017-01-01

    Clinical guidelines recommend double-dose hepatitis B vaccination for patients requiring dialysis, due to an increased risk of hepatitis B infection and reduced vaccine responsiveness. There are no recommendations for patients with chronic kidney disease (CKD) prior to dialysis. We performed a systematic review and meta-analysis of randomized and quasi-randomized trials comparing efficacy (seroresponses) and harms of double-dose compared with standard-dose hepatitis B vaccination in patients with CKD, including those requiring dialysis. A systematic literature search (CENTRAL, MEDLINE and EMBASE) was performed using a predetermined search strategy. Relative risks were calculated from pooled data using a random-effects model with subgroup analysis by dialysis requirement and vaccine type. Seven studies (501 patients) fulfilled review criteria: four in patients receiving dialysis and three in patients not receiving dialysis. The incidence of seroconversion was not increased with double-dose vaccination overall [risk ratio (RR) 1.17, 95% confidence interval (CI) 0.98-1.39], by dialysis requirement or vaccine type. The incidence of seroprotection (reported by only four studies) was increased with double-dose vaccination overall (RR 1.53, 95% CI 1.17-2.00) but not by dialysis requirement. Adverse events were not reported by treatment arm, precluding comparison. The overall quality of included studies was moderate to low. The current data do not support clinical guideline recommendations for administering double-dose vaccination for patients with CKD as seroconversion was not improved and seroprotection was inadequately assessed. Large high-quality studies are required to overcome the current evidence gap regarding vaccine dosing in CKD. © The Author 2016. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

  12. Clinical radiation doses for spinal cord: the 1988 international questionnaire

    International Nuclear Information System (INIS)

    Fowler, J.F.; Bogaert, W. vanden; Scheuren, E. van der; Bentzen, S.M.; Bond, S.J.; Ang, K.K.; Kogel, A.J. van der

    2000-01-01

    Emmanuel van der Schueren gave a keynote lecture at the 1988 ASTRO annual conference pointing out that the spinal cord 'tolerance doses' then prescribed were probably unnecessarily cautious, resulting in probable underdosing of some tumours. This lecture was supported both by an international questionnaire which he and two of the present authors had conducted, and by animal experimental data. In 1997 he initiated a 10-year follow-up questionnaire, the results of which are summarised here. The present report analyses the chance in prescriptions from 1988 to 1998 and the variation in prescriptions among various regions of the World. The main conclusion is that prescribed dose levels have increased significantly in this period. Large geographical variations still exist. Among responders who use a formula to correct for changed dose per fraction, 90% are now using the linear-quadratic model vs. 33% in 1988. The current status of clinically acceptable doses to spinal cord in 2-Gy fractions is discussed briefly. Further details from the responses to the 1998 questionnaire will be presented in another publication. (author)

  13. Prescribed dose versus calculated dose of spinal cord in standard head and neck irradiation assessed by 3-D plan

    Directory of Open Access Journals (Sweden)

    Dipanjan Majumder

    2014-01-01

    Full Text Available Background and Purpose: Spinal cord toxicity can be dreaded complication while treating head and neck cancer by conventional radiotherapy. Cord sparing approach is applied by two phase planning in conventional head neck radiotherapy. In spite of cord sparing approach spinal cord still receives considerable scatter dose. Our study aims to do the volumetric analysis of spinal cord dosimetry and to correlate with the clinical findings. Materials and Methods: Treatment planning was done in two phases. First phase treatment fi elds include gross disease- both tumor and involved nodes. in the second phase, treatment field shrinkage was done to cover the gross disease sparing the spinal cord. These fields are termed as off-cord fields. 42 patients with histological proven squamous cell carcinoma of the head and neck region were analysed with two groups. In Group A, 46 Gy was given in 23 fractions, and then tumor-boost with off-cord fi eld received 24 Gy in 12 fractions. In Group B 50 Gy was prescribed in 25 fractions initially, then off-cord fi eld given 20 Gy in 10 fractions to analyze theoutcome. Planning Computed tomography (CT scan was done Philips Brilliance 16 slice CT scan machine, and contouring and dose calculation were done at ASHA treatment planning software. Results: Maximum dose and dose at 1 cm3, 2 cm3, and 5 cm3 were calculated. Maximum dose to cord was 52.6 Gy (range 48.1-49.7 Gy in Group A and 54.3 Gy (range 51.48-52.33 Gy in Group B initially. Off-cord fi elds received mean dose 8.07 Gy (85.85% of maximum in Group A and 5.47 Gy (86.84% of maximum in Group B. At the end of 6 months from the last date of radiotherapy, grade 1 spinal cord toxicity found in two patients in Group A and one patient in Group B respectively (P = 0.55. Both groups received additional dose, which are higher than the prescribed dose, but no patients show significant spinal cord toxicity after 6 month of follow-up. Conclusion: Spinal cord received scatter dose

  14. Low dose versus standard dose of corticosteroids in the management of adverse events of special interest from abiraterone acetate: data from a literature-based meta-analysis.

    Science.gov (United States)

    Roviello, Giandomenico; Corona, Silvia Paola; Generali, Daniele

    2017-08-29

    Abiraterone acetate is a CYP-17 inhibitor approved for the treatment of prostate cancer. Abiraterone acetate (AA) therapy is associated with toxicities, including hypokalemia, hypertension, liver function test abnormalities and cardiac events. These adverse events are traditionally managed with a standard dose of corticosteroids. However, preliminary data are available on the use of a lower dose of corticosteroids. The aim of this report is to perform a pooled analysis evaluating the risk ratio (RR) of AA-related adverse events of special interest associated with low or standard dose of corticosteroids. A total of 5374 cases from 4 randomized clinical trials were included. Subgroup analysis according to corticosteroids dosage revealed a higher RR of adverse events associated with a dose of 5 mg, compared to 10 mg. In particular, there was a statistically significant higher RR of hypokalemia and ALT/AST increase, and only a modest risk increase for cardiac disorders and hypertension. In conclusion, given the limitations of a literature-based study, in comparison with a meta-analysis based on individual patients' data, our study identified a relatively small increase in RR for hypertension and cardiac disorders and a bigger increase of RR for hypokalemia and ALT/AST toxicity when 5 mg, rather than 10 mg of corticosteroids were administered to manage adverse events of special interest from AA. Further studies with specified end-points are awaited to confirm these results.

  15. Standardized clinical photography: the role of flash.

    Science.gov (United States)

    Cariello, Angelino; Viana, Giovanni André; Osaki, Midori; Pamplona, André Luis; Höfling-Lima, Ana Luisa

    2012-01-01

    Medical photographic documentation is important for professional, research, and ethical concerns. This study analyzed the possible interference that the flash could cause on evaluation of lower eyelid cosmetic results. Standardized photographs with and without flash were taken of 10 patients with dermatochalasis. The photographs were evaluated by 3 independent observers, as before (without flash) and after (with flash) an alternative esthetic treatment of the lower eyelid. The observers rated the overall cosmetic improvement of the lower eyelid photographs on a visual analog scale. The 3 surgeons believed that there was improvement in cosmetic outcome from the first (without flash) to the second (with flash) picture. The results indicate that a simple flash addition in one of 2 consecutive photographs, taken seconds apart, could influence the impression of experienced surgeons on the final outcome of oculoplastic surgeries and may constitute a bias in observer-dependent studies.

  16. Population pharmacokinetics of piperacillin in the early phase of septic shock: does standard dosing result in therapeutic plasma concentrations?

    Science.gov (United States)

    Öbrink-Hansen, Kristina; Juul, Rasmus Vestergaard; Storgaard, Merete; Thomsen, Marianne Kragh; Hardlei, Tore Forsingdal; Brock, Birgitte; Kreilgaard, Mads; Gjedsted, Jakob

    2015-11-01

    Antibiotic dosing in septic shock patients poses a challenge for clinicians due to the pharmacokinetic (PK) variability seen in this patient population. Piperacillin-tazobactam is often used for empirical treatment, and initial appropriate dosing is crucial for reducing mortality. Accordingly, we determined the pharmacokinetic profile of piperacillin (4 g) every 8 h, during the third consecutive dosing interval, in 15 patients treated empirically for septic shock. We developed a population pharmacokinetic model to assess empirical dosing and to simulate alternative dosing regimens and modes of administration. Time above the MIC (T>MIC) predicted for each patient was evaluated against clinical breakpoint MIC for Pseudomonas aeruginosa (16 mg/liter). Pharmacokinetic-pharmacodynamic (PK/PD) targets evaluated were 50% fT>4×MIC and 100% fT>MIC. A population PK model was developed using NONMEM, and data were best described by a two-compartment model. Central and intercompartmental clearances were 3.6 liters/h (relative standard error [RSE], 15.7%) and 6.58 liters/h (RSE, 16.4%), respectively, and central and peripheral volumes were 7.3 liters (RSE, 11.8%) and 3.9 liters (RSE, 9.7%), respectively. Piperacillin plasma concentrations varied considerably between patients and were associated with levels of plasma creatinine. Patients with impaired renal function were more likely to achieve predefined PK/PD targets than were patients with preserved or augmented renal function. Simulations of alternative dosing regimens showed that frequent intermittent bolus dosing as well as dosing by extended and continuous infusion increases the probability of attaining therapeutic plasma concentrations. For septic shock patients with preserved or augmented renal function, dose increment or prolonged infusion of the drug needs to be considered. (This study has been registered at ClinicalTrials.gov under registration no. NCT02306928.). Copyright © 2015, American Society for Microbiology

  17. Exposure to low dose ionising radiation: Molecular and clinical consequences.

    LENUS (Irish Health Repository)

    Martin, Lynn M

    2014-07-10

    This review article provides a comprehensive overview of the experimental data detailing the incidence, mechanism and significance of low dose hyper-radiosensitivity (HRS). Important discoveries gained from past and present studies are mapped and highlighted to illustrate the pathway to our current understanding of HRS and the impact of HRS on the cellular response to radiation in mammalian cells. Particular attention is paid to the balance of evidence suggesting a role for DNA repair processes in the response, evidence suggesting a role for the cell cycle checkpoint processes, and evidence investigating the clinical implications\\/relevance of the effect.

  18. Standards in clinical decision support: activities in health level seven.

    Science.gov (United States)

    Jenders, Robert A; Jenders, Robert Allen; Del Fiol, Guilherme; Kawamoto, Kensaku; Sailors, R Matthew

    2008-11-06

    Health Level Seven (HL7) has evolved into an international standards development organization (SDO) with a suite of standards. Prominent among these are formalisms related to clinical decision support, including the Arden Syntax, GELLO and Decision Support Service (DSS) standards. Continuing improvement in these standards and ongoing development of future decision support standards require wide participation in order to maximize their success. Accordingly, the purpose of the workshop is twofold. First, instructors will convey the latest developments regarding existing decision support standards and related efforts to develop new standards. Second, the instructors will solicit feedback so that attendees who do not participate in HL7 can have input into the standards activities of that organization. The instructors of this workshop, who are the co-chairs and/or members of the Clinical Decision Support Technical Committee of HL7, will review progress in these areas. They will present the details of the ongoing development of the extant Arden Syntax, GELLO and DSS standards. They will discuss work on current draft and proposed future standards, including the Infobutton communication and Order Set standards that are undergoing development in anticipation of certification as standards. Finally, they will solicit discussion regarding the future direction of standards development in these areas.

  19. Clinical impact of MRI assisted dose volume adaptation and dose escalation in brachytherapy of locally advanced cervix cancer

    International Nuclear Information System (INIS)

    Poetter, Richard; Dimopoulos, Johannes; Georg, Petra; Lang, Stefan; Waldhaeusl, Claudia; Wachter-Gerstner, Natascha; Weitmann, Hajo; Reinthaller, Alexander; Knocke, Tomas Hendrik; Wachter, Stefan; Kirisits, Christian

    2007-01-01

    Background: To investigate the clinical impact of MRI based cervix cancer brachytherapy combined with external beam radiochemotherapy applying dose volume adaptation and dose escalation in a consecutive group of patients with locally advanced cervix cancer. Methods: In the period 1998-2003, 145 patients with cervix cancer stages IB-IVA were treated with definitive radiotherapy +/- cisplatin chemotherapy. Median age was 60 years. In 67 patients, the tumour size was 2-5 cm, in 78 patients it was >5 cm. In 29 cases the standard intracavitary technique was combined with interstitial brachytherapy. Total prescribed dose was 80-85 Gy (total biologically equivalent dose in 2 Gy fractions). Since 2001, MRI based treatment planning integrated systematic concepts for High Risk Clinical Target Volume (HR CTV) and organs at risk (OAR), biological modelling, Dose-Volume-Histogram analysis, dose-volume-adaptation (D90, D 2 cm 3 ), and dose escalation, if appropriate and feasible. Findings: Dose volume adaptation was performed in 130/145 patients. The mean D90 during the whole period was 86 Gy, with a mean D90 of 81 Gy and 90 Gy during the first and second period, respectively (p 5 cm it was 71% in 1998-2000 and 90% in 2001-2003 (p = 0.05). Progression free survival (PFS) for true pelvis (local control) was 85%, PFS for distant metastases was 80%, both at 3 years. Local control for tumours >5 cm was 64% in 1998-2000 and 82% in 2001-2003 (p = 0.09) and 100% and 96%, respectively, for tumours 2-5 cm. PFS for distant metastases remained the same during the two treatment periods with 79% and 80%. Overall survival (OS) was 58%, and cancer-specific survival (CSS) was 68% at 3 years. In the two different periods improvement in OS was from 53% to 64% (p = 0.03) and in CSS from 62% to 74% (p = 0.13). Improvement occurred only in tumours >5 cm: OS 28% versus 58% (p = 0.003); CSS 40% versus 62% (p = 0.07). Actuarial late morbidity rate (LENT SOMA, grades 3 and 4) at 3 years was

  20. Reliability of dose volume constraint inference from clinical data

    Science.gov (United States)

    Lutz, C. M.; Møller, D. S.; Hoffmann, L.; Knap, M. M.; Alber, M.

    2017-04-01

    Dose volume histogram points (DVHPs) frequently serve as dose constraints in radiotherapy treatment planning. An experiment was designed to investigate the reliability of DVHP inference from clinical data for multiple cohort sizes and complication incidence rates. The experimental background was radiation pneumonitis in non-small cell lung cancer and the DVHP inference method was based on logistic regression. From 102 NSCLC real-life dose distributions and a postulated DVHP model, an ‘ideal’ cohort was generated where the most predictive model was equal to the postulated model. A bootstrap and a Cohort Replication Monte Carlo (CoRepMC) approach were applied to create 1000 equally sized populations each. The cohorts were then analyzed to establish inference frequency distributions. This was applied to nine scenarios for cohort sizes of 102 (1), 500 (2) to 2000 (3) patients (by sampling with replacement) and three postulated DVHP models. The Bootstrap was repeated for a ‘non-ideal’ cohort, where the most predictive model did not coincide with the postulated model. The Bootstrap produced chaotic results for all models of cohort size 1 for both the ideal and non-ideal cohorts. For cohort size 2 and 3, the distributions for all populations were more concentrated around the postulated DVHP. For the CoRepMC, the inference frequency increased with cohort size and incidence rate. Correct inference rates  >85 % were only achieved by cohorts with more than 500 patients. Both Bootstrap and CoRepMC indicate that inference of the correct or approximate DVHP for typical cohort sizes is highly uncertain. CoRepMC results were less spurious than Bootstrap results, demonstrating the large influence that randomness in dose-response has on the statistical analysis.

  1. Dose computation in conformal radiation therapy including geometric uncertainties: Methods and clinical implications

    Science.gov (United States)

    Rosu, Mihaela

    The aim of any radiotherapy is to tailor the tumoricidal radiation dose to the target volume and to deliver as little radiation dose as possible to all other normal tissues. However, the motion and deformation induced in human tissue by ventilatory motion is a major issue, as standard practice usually uses only one computed tomography (CT) scan (and hence one instance of the patient's anatomy) for treatment planning. The interfraction movement that occurs due to physiological processes over time scales shorter than the delivery of one treatment fraction leads to differences between the planned and delivered dose distributions. Due to the influence of these differences on tumors and normal tissues, the tumor control probabilities and normal tissue complication probabilities are likely to be impacted upon in the face of organ motion. In this thesis we apply several methods to compute dose distributions that include the effects of the treatment geometric uncertainties by using the time-varying anatomical information as an alternative to the conventional Planning Target Volume (PTV) approach. The proposed methods depend on the model used to describe the patient's anatomy. The dose and fluence convolution approaches for rigid organ motion are discussed first, with application to liver tumors and the rigid component of the lung tumor movements. For non-rigid behavior a dose reconstruction method that allows the accumulation of the dose to the deforming anatomy is introduced, and applied for lung tumor treatments. Furthermore, we apply the cumulative dose approach to investigate how much information regarding the deforming patient anatomy is needed at the time of treatment planning for tumors located in thorax. The results are evaluated from a clinical perspective. All dose calculations are performed using a Monte Carlo based algorithm to ensure more realistic and more accurate handling of tissue heterogeneities---of particular importance in lung cancer treatment planning.

  2. Multicentre dose audit for clinical trials of radiation therapy in Asia.

    Science.gov (United States)

    Mizuno, Hideyuki; Fukuda, Shigekazu; Fukumura, Akifumi; Nakamura, Yuzuru-Kutsutani; Jianping, Cao; Cho, Chul-Koo; Supriana, Nana; Dung, To Anh; Calaguas, Miriam Joy; Devi, C R Beena; Chansilpa, Yaowalak; Banu, Parvin Akhter; Riaz, Masooma; Esentayeva, Surya; Kato, Shingo; Karasawa, Kumiko; Tsujii, Hirohiko

    2017-05-01

    A dose audit of 16 facilities in 11 countries has been performed within the framework of the Forum for Nuclear Cooperation in Asia (FNCA) quality assurance program. The quality of radiation dosimetry varies because of the large variation in radiation therapy among the participating countries. One of the most important aspects of international multicentre clinical trials is uniformity of absolute dose between centres. The National Institute of Radiological Sciences (NIRS) in Japan has conducted a dose audit of participating countries since 2006 by using radiophotoluminescent glass dosimeters (RGDs). RGDs have been successfully applied to a domestic postal dose audit in Japan. The authors used the same audit system to perform a dose audit of the FNCA countries. The average and standard deviation of the relative deviation between the measured and intended dose among 46 beams was 0.4% and 1.5% (k = 1), respectively. This is an excellent level of uniformity for the multicountry data. However, of the 46 beams measured, a single beam exceeded the permitted tolerance level of ±5%. We investigated the cause for this and solved the problem. This event highlights the importance of external audits in radiation therapy. © The Author 2016. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

  3. Parkinson’s Disease: Low-Dose Haloperidol Increases Dopamine Receptor Sensitivity and Clinical Response

    Directory of Open Access Journals (Sweden)

    Craig J. Hudson

    2014-01-01

    Full Text Available Background. It is known that ultra-low doses of haloperidol can cause dopamine supersensitivity of dopamine D2 receptors and related behaviour in animals. Objective. The objective was to determine whether a daily ultra-low dose of 40 micrograms of haloperidol could enhance the clinical action of levodopa in Parkinson’s disease patients. Method. While continuing their daily treatment with levodopa, 16 patients with Parkinson’s disease were followed weekly for six weeks. They received an add-on daily dose of 40 micrograms of haloperidol for the first two weeks only. The SPES/SCOPA scale (short scale for assessment of motor impairments and disabilities in Parkinson’s disease was administered before treatment and weekly throughout the trial. Results. The results showed a mean decrease in SPES/SCOPA scores after one week of the add-on treatment. Conclusion. SCOPA scores decreased after the addition of low-dose haloperidol to the standard daily levodopa dose. This finding is consistent with an increase in sensitivity of dopamine D2 receptors induced by haloperidol. Such treatment for Parkinson’s disease may possibly permit the levodopa dose to be reduced and, thus, delay the onset of levodopa side effects.

  4. Parkinson's disease: low-dose haloperidol increases dopamine receptor sensitivity and clinical response.

    Science.gov (United States)

    Hudson, Craig J; Seeman, Philip; Seeman, Mary V

    2014-01-01

    Background. It is known that ultra-low doses of haloperidol can cause dopamine supersensitivity of dopamine D2 receptors and related behaviour in animals. Objective. The objective was to determine whether a daily ultra-low dose of 40 micrograms of haloperidol could enhance the clinical action of levodopa in Parkinson's disease patients. Method. While continuing their daily treatment with levodopa, 16 patients with Parkinson's disease were followed weekly for six weeks. They received an add-on daily dose of 40 micrograms of haloperidol for the first two weeks only. The SPES/SCOPA scale (short scale for assessment of motor impairments and disabilities in Parkinson's disease) was administered before treatment and weekly throughout the trial. Results. The results showed a mean decrease in SPES/SCOPA scores after one week of the add-on treatment. Conclusion. SCOPA scores decreased after the addition of low-dose haloperidol to the standard daily levodopa dose. This finding is consistent with an increase in sensitivity of dopamine D2 receptors induced by haloperidol. Such treatment for Parkinson's disease may possibly permit the levodopa dose to be reduced and, thus, delay the onset of levodopa side effects.

  5. Intermediate-dose cytarabine plus mitoxantrone versus standard-dose cytarabine plus daunorubicine for acute myeloid leukemia in elderly patients.

    Science.gov (United States)

    Röllig, C; Kramer, M; Gabrecht, M; Hänel, M; Herbst, R; Kaiser, U; Schmitz, N; Kullmer, J; Fetscher, S; Link, H; Mantovani-Löffler, L; Krümpelmann, U; Neuhaus, T; Heits, F; Einsele, H; Ritter, B; Bornhäuser, M; Schetelig, J; Thiede, C; Mohr, B; Schaich, M; Platzbecker, U; Schäfer-Eckart, K; Krämer, A; Berdel, W E; Serve, H; Ehninger, G; Schuler, U

    2018-01-30

    The combination of intermediate-dose cytarabine plus mitoxantrone (IMA) can induce high complete remission rates with acceptable toxicity in elderly patients with acute myeloid leukemia (AML). We present the final results of a randomized-controlled trial comparing IMA with the standard 7 + 3 induction regimen consisting of continuous infusion daunorubicin plus cytarabine (DA). Patients with newly diagnosed AML >60 years were randomized to receive either intermediate-dose cytarabine (1000 mg/m2 BID days 1,3,5,7) plus mitoxantrone (10 mg/m2 days 1-3) (IMA) or standard induction therapy with cytarabine (100 mg/m2 continuously days 1-7) plus daunorubicin (45 mg/m2 days 3-5) (DA). Patients in complete remission after DA received intermediate-dose cytarabine plus amsacrine as consolidation treatment, whereas patients after IMA were consolidated with standard-dose cytarabine plus mitoxantrone. Between February 2005 and October 2009, 485 patients were randomized; 241 for treatment arm DA and 244 for IMA; 76% of patients were >65 years. The CR rate after DA was 39% (95%-CI; 33-45) versus 55% (95%-CI; 49-61) after IMA (OR 1.89, p=0.001). The six-week early-death rate was 14% in both arms. Relapse-free survival (RFS) curves were superimposable in the first year, but separated afterwards, resulting in 3-year RFS rates of 29% versus 14% in the DA versus IMA arms, respectively (p=0.042). The median OS was 10 months in both arms (p=0.513). The dose escalation of cytarabine in induction therapy lead to improved remission rates in the elderly AML patients. This did not translate into a survival advantage, most likely due to differences in consolidation treatment. Thus, effective consolidation strategies need to be further explored. In combination with an effective consolidation strategy, the use of intermediate dose cytarabine in induction may improve curative treatment for elderly AML patients. © The Author 2018. Published by Oxford University Press on behalf of the

  6. Standard Guide for Absorbed-Dose Mapping in Radiation Processing Facilities

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2003-01-01

    1.1 This document provides guidance in determining absorbed-dose distributions in products, materials or substances irradiated in gamma, X-ray (bremsstrahlung) and electron beam facilities. Note 1—For irradiation of food and the radiation sterilization of health care products, other specific ISO and ISO/ASTM standards containing dose mapping requirements exist. For food irradiation, see ISO/ASTM 51204, Practice for Dosimetry in Gamma Irradiation Facilities for Food Processing and ISO/ASTM 51431, Practice for Dosimetry in Electron and Bremsstrahlung Irradiation Facilities for Food Processing. For the radiation sterilization of health care products, see ISO 11137: 1995, Sterilization of Health Care Products Requirements for Validation and Routine Control Radiation Sterilization. In those areas covered by ISO 11137, that standard takes precedence. ISO/ASTM Practice 51608, ISO/ASTM Practice 51649, and ISO/ASTM Practice 51702 also contain dose mapping requirements. 1.2 Methods of analyzing the dose map data ar...

  7. Clinical implementation of full Monte Carlo dose calculation in proton beam therapy

    International Nuclear Information System (INIS)

    Paganetti, Harald; Jiang, Hongyu; Parodi, Katia; Slopsema, Roelf; Engelsman, Martijn

    2008-01-01

    The goal of this work was to facilitate the clinical use of Monte Carlo proton dose calculation to support routine treatment planning and delivery. The Monte Carlo code Geant4 was used to simulate the treatment head setup, including a time-dependent simulation of modulator wheels (for broad beam modulation) and magnetic field settings (for beam scanning). Any patient-field-specific setup can be modeled according to the treatment control system of the facility. The code was benchmarked against phantom measurements. Using a simulation of the ionization chamber reading in the treatment head allows the Monte Carlo dose to be specified in absolute units (Gy per ionization chamber reading). Next, the capability of reading CT data information was implemented into the Monte Carlo code to model patient anatomy. To allow time-efficient dose calculation, the standard Geant4 tracking algorithm was modified. Finally, a software link of the Monte Carlo dose engine to the patient database and the commercial planning system was established to allow data exchange, thus completing the implementation of the proton Monte Carlo dose calculation engine ('DoC++'). Monte Carlo re-calculated plans are a valuable tool to revisit decisions in the planning process. Identification of clinically significant differences between Monte Carlo and pencil-beam-based dose calculations may also drive improvements of current pencil-beam methods. As an example, four patients (29 fields in total) with tumors in the head and neck regions were analyzed. Differences between the pencil-beam algorithm and Monte Carlo were identified in particular near the end of range, both due to dose degradation and overall differences in range prediction due to bony anatomy in the beam path. Further, the Monte Carlo reports dose-to-tissue as compared to dose-to-water by the planning system. Our implementation is tailored to a specific Monte Carlo code and the treatment planning system XiO (Computerized Medical Systems Inc

  8. Semi-Supervised Tripled Dictionary Learning for Standard-dose PET Image Prediction using Low-dose PET and Multimodal MRI

    Science.gov (United States)

    Wang, Yan; Ma, Guangkai; An, Le; Shi, Feng; Zhang, Pei; Lalush, David S.; Wu, Xi; Pu, Yifei; Zhou, Jiliu; Shen, Dinggang

    2017-01-01

    Objective To obtain high-quality positron emission tomography (PET) image with low-dose tracer injection, this study attempts to predict the standard-dose PET (S-PET) image from both its low-dose PET (L-PET) counterpart and corresponding magnetic resonance imaging (MRI). Methods It was achieved by patch-based sparse representation (SR), using the training samples with a complete set of MRI, L-PET and S-PET modalities for dictionary construction. However, the number of training samples with complete modalities is often limited. In practice, many samples generally have incomplete modalities (i.e., with one or two missing modalities) that thus cannot be used in the prediction process. In light of this, we develop a semi-supervised tripled dictionary learning (SSTDL) method for S-PET image prediction, which can utilize not only the samples with complete modalities (called complete samples) but also the samples with incomplete modalities (called incomplete samples), to take advantage of the large number of available training samples and thus further improve the prediction performance. Results Validation was done on a real human brain dataset consisting of 18 subjects, and the results show that our method is superior to the SR and other baseline methods. Conclusion This work proposed a new S-PET prediction method, which can significantly improve the PET image quality with low-dose injection. Significance The proposed method is favorable in clinical application since it can decrease the potential radiation risk for patients. PMID:27187939

  9. Establishment of quality assessment standard for mammographic equipment: evaluation of phantom and clinical images

    International Nuclear Information System (INIS)

    Lee, Sung Hoon; Choe, Yeon Hyeon; Chung, Soo Young

    2005-01-01

    The purpose of this study was to establish a quality standard for mammographic equipment Korea and to eventually improve mammographic quality in clinics and hospitals throughout Korea by educating technicians and clinic personnel. For the phantom test and on site assessment, we visited 37 sites and examined 43 sets of mammographic equipment. Items that were examined include phantom test, radiation dose measurement, developer assessment, etc. The phantom images were assessed visually and by optical density measurements. For the clinical image assessment, clinical images from 371 sites were examined following the new Korean standard for clinical image evaluation. The items examined include labeling, positioning, contrast, exposure, artifacts, collimation among others. Quality standard of mammographic equipment was satisfied in all equipment on site visits. Average mean glandular dose was 114.9 mRad. All phantom image test scores were over 10 points (average, 10.8 points). However, optical density measurements were below 1.2 in 9 sets of equipment (20.9%). Clinical image evaluation revealed appropriate image quality in 83.5%, while images from non-radiologist clinics were adequate in 74.6% (91/122), which was the lowest score of any group. Images were satisfactory in 59.0% (219/371) based on evaluation by specialists following the new Korean standard for clinical image evaluation. Satisfactory images had a mean score of 81.7 (1 S.D. =8.9) and unsatisfactory images had a mean score of 61.9 (1 S.D = 11). The correlation coefficient between the two observers was 0.93 (ρ < 0.01) in 49 consecutive cases. The results of the phantom tests suggest that optical density measurements should be performed as part of a new quality standard for mammographic equipment. The new clinical evaluation criteria that was used in this study can be implemented with some modifications for future mammography quality control by the Korean government

  10. Determination of dialysis dose: a clinical comparison of methods.

    Science.gov (United States)

    Ahrenholz, Peter; Taborsky, Petr; Bohling, Margot; Rawer, Peter; Ibrahim, Noureddin; Gajdos, Martin; Machek, Petr; Sagova, Michaela; Gruber, Hans; Moucka, Pavel; Rychlik, Ivan; Leimenstoll, Gerd; Vyskocil, Pavel; Toenne, Gunter; Possnickerova, Jindriska; Woggan, Joerg; Riegel, Werner; Schneider, Helmut; Wojke, Ralf

    2011-01-01

    Guidelines recommend regular measurements of the delivered hemodialysis dose Kt/V. Nowadays, automatic non-invasive online measurements are available as alternatives to the conventional method with blood sampling, laboratory analysis, and calculation. In a prospective clinical trial, three different methods determining dialysis dose were simultaneously applied: Kt/V(Dau) (conventional method with Daugirdas' formula), Kt/V(OCM) [online clearance measurement (OCM) with urea distribution volume V based on anthropometric estimate], and Kt/V(BCM) [OCM measurement with V measured by bioimpedance analysis (Body Composition Monitor)]. 1,076 hemodialysis patients were analyzed. The dialysis dose was measured as Kt/V(Dau) = 1.74 ± 0.45, Kt/V(OCM) = 1.47 ± 0.34, and Kt/V(BCM) = 1.65 ± 0.42. The difference between Kt/V(OCM) and Kt/V(BCM) was due to the difference between anthropometric estimated V(Watson) and measured V(BCM). Compared to Kt/V(Dau), Kt/V(OCM) was 15% lower and Kt/V(BCM) 5% lower. Kt/V(Dau) was incidentally prone to falsely high values due to operative errors, whereas in these cases OCM-based measurements Kt/V(OCM) and Kt/V(BCM) delivered realistic values. The automated OCM Kt/V(OCM) with anthropometric estimation of urea distribution volume was the easiest method to use, but Kt/V(BCM) with measured urea distribution volume was closer to the conventional method. Copyright © 2011 S. Karger AG, Basel.

  11. 466 Bee venom Immunotherapy with Standardized Extract, Two Case Comunication and Clinical Progress

    Science.gov (United States)

    Cardona, Aristoteles Alvarez; Nieto, Leticia Hernandez; Melendez, Alvaro Pedroza

    2012-01-01

    Background Bee venom immunotherapy is a safe and effective treatment, indicated in patients with previous history of severe systemic reactions to bee venom, demonstrating succesful desensitization in more than 90% of cases with standardized extract. Currently in Mexico there is no standardized extract commercially available for treatment, despite of having high activity of beekeeping and occupational exposure with at least 17,478 registered stings per year and an annually honey production of nearly 70 tons. Methods We present the clinical progress of 2 patients with history of severe systemic reactions to bee venom and occupational exposure, both with demonstrated sensitization by specific IgE and who underwent specific immunotherapy with standardized extract (Alk-US) reaching a maintenance weekly dose of 100 mcg (PLA2) for the last 4 years. Results Both patients sufered of accidental stings after reached the maintenance dose presenting mild local reactions to stings. Both patients had very different clinical course presenting a wide variety of adverse reactions during desensitization protocol; from mild local to generalized reactions all generally well tolerated allowed to reach the maintenance dose with succesful desensitization proved by accidental exposure without severe systemic reactions. Conclusions Bee venom specific immunotherapy with standardized extract is a well tolerated and efective treatment preventing the development of life threathening reactions in sensitized patients. It is important to promote the use and availability of standardized extract in developing countries with poor safety measures and high occupational exposure.

  12. SU-G-BRC-15: The Potential Clinical Significance of Dose Mapping Error for Intra- Fraction Dose Mapping for Lung Cancer Patients

    Energy Technology Data Exchange (ETDEWEB)

    Sayah, N [Thomas Cancer Center, Richmond, VA (United States); Weiss, E [Virginia Commonwealth University, Richmond, Virginia (United States); Watkins, W [University of Virginia, Charlottesville, VA (United States); Siebers, J [University of Virginia Health System, Charlottesville, VA (United States)

    2016-06-15

    Purpose: To evaluate the dose-mapping error (DME) inherent to conventional dose-mapping algorithms as a function of dose-matrix resolution. Methods: As DME has been reported to be greatest where dose-gradients overlap tissue-density gradients, non-clinical 66 Gy IMRT plans were generated for 11 lung patients with the target edge defined as the maximum 3D density gradient on the 0% (end of inhale) breathing phase. Post-optimization, Beams were copied to 9 breathing phases. Monte Carlo dose computed (with 2*2*2 mm{sup 3} resolution) on all 10 breathing phases was deformably mapped to phase 0% using the Monte Carlo energy-transfer method with congruent mass-mapping (EMCM); an externally implemented tri-linear interpolation method with voxel sub-division; Pinnacle’s internal (tri-linear) method; and a post-processing energy-mass voxel-warping method (dTransform). All methods used the same base displacement-vector-field (or it’s pseudo-inverse as appropriate) for the dose mapping. Mapping was also performed at 4*4*4 mm{sup 3} by merging adjacent dose voxels. Results: Using EMCM as the reference standard, no clinically significant (>1 Gy) DMEs were found for the mean lung dose (MLD), lung V20Gy, or esophagus dose-volume indices, although MLD and V20Gy were statistically different (2*2*2 mm{sup 3}). Pinnacle-to-EMCM target D98% DMEs of 4.4 and 1.2 Gy were observed ( 2*2*2 mm{sup 3}). However dTransform, which like EMCM conserves integral dose, had DME >1 Gy for one case. The root mean square RMS of the DME for the tri-linear-to- EMCM methods was lower for the smaller voxel volume for the tumor 4D-D98%, lung V20Gy, and cord D1%. Conclusion: When tissue gradients overlap with dose gradients, organs-at-risk DME was statistically significant but not clinically significant. Target-D98%-DME was deemed clinically significant for 2/11 patients (2*2*2 mm{sup 3}). Since tri-linear RMS-DME between EMCM and tri-linear was reduced at 2*2*2 mm{sup 3}, use of this resolution is

  13. Advances in absorbed dose measurement standards at the australian radiation laboratory

    International Nuclear Information System (INIS)

    Boas, J.F.; Hargrave, N.J.; Huntley, R.B.; Kotler, L.H.; Webb, D.V.; Wise, K.N.

    1996-01-01

    The applications of ionising radiation in the medical and industrial fields require both an accurate knowledge of the amount of ionising radiation absorbed by the medium in question and the capability of relating this to National and International standards. The most useful measure of the amount of radiation is the absorbed dose which is defined as the energy absorbed per unit mass. For radiotherapy, the reference medium is water, even though the measurement of the absorbed dose to water is not straightforward. Two methods are commonly used to provide calibrations in absorbed dose to water. The first is the calibration of the chamber in terms of exposure in a Cobalt-60 beam, followed by the conversion by a protocol into dose to water in this and higher energy beams. The other route is via the use of a graphite calorimeter as a primary standard device, where the conversion from absorbed dose to graphite to absorbed dose in water is performed either by theoretical means making use of cavity ionisation theory, or by experiment where the graphite calorimeter and secondary standard ionisation chamber are placed at scaled distances from the source of the radiation beam (known as the Dose-Ratio method). Extensive measurements have been made at Cobalt-60 at ARL using both the exposure and absorbed dose to graphite routes. Agreement between the ARL measurements and those based on standards maintained by ANSTO and NPL is within ± 0.3%. Absorbed dose measurements have also been performed at ARL with photon beams of nominal energy 16 and 19 MeV obtained from the ARL linac. The validity of the protocols at high photon energies, the validity of the methods used to convert from absorbed dose in graphite to absorbed dose in water and the validity of the indices used to specify the beams are discussed. Brief mention will also be made of the establishment of a calibration facility for neutron monitors at ARL and of progress in the development of ERP dosimetry

  14. Low-Dose and Standard-Dose Unenhanced Helical Computed Tomography for the Assessment of Acute Renal Colic: Prospective Comparative Study

    International Nuclear Information System (INIS)

    Kim, Bong Soo; Hwang, Im Kyung; Choi, Yo Won; Namkung, Sook; Kim, Heung Cheol; Hwang, Woo Cheol; Choi, Kuk Myung; Park, Ji Kang; Han, Tae Il; Kang, Weechang

    2005-01-01

    Purpose: To compare the efficacy of low-dose and standard-dose computed tomography (CT) for the diagnosis of ureteral stones. Material and Methods: Unenhanced helical CT was performed with both a standard dose (260 mAs, pitch 1.5) and a low dose (50 mAs, pitch 1.5) in 121 patients suspected of having acute renal colic. The two studies were prospectively and independently interpreted for the presence and location of ureteral stones, abnormalities unrelated to stone disease, identification of secondary signs, i.e. hydronephrosis and perinephric stranding, and tissue rim sign. The standard-dose CT images were interpreted by one reviewer and the low-dose CT images independently by two reviewers unaware of the standard-dose CT findings. The findings of the standard and low-dose CT scans were compared with the exact McNemar test. Interobserver agreements were assessed with kappa analysis. The effective radiation doses resulting from two different protocols were calculated by means of commercially available software to which the Monte-Carlo phantom model was given. Results: The sensitivity, specificity, and accuracy of standard-dose CT for detecting ureteral stones were 99%, 93%, and 98%, respectively, whereas for the two reviewers the sensitivity of low-dose CT was 93% and 95%, specificity 86%, and accuracy 92% and 94%. We found no significant differences between standard-dose and low-dose CT in the sensitivity and specificity for diagnosing ureter stones ( P >0.05 for both). However, the sensitivity of low-dose CT for detection of 19 stones less than or equal to 2 mm in diameter was 79% and 68%, respectively, for the two reviewers. Low-dose CT was comparable to standard-dose CT in visualizing hydronephrosis and the tissue rim sign. Perinephric stranding was far less clear on low-dose CT. Low-dose CT had the same diagnostic performance as standard-dose CT in diagnosing alternative diseases. Interobserver agreement between the two low-dose CT reviewers in the diagnosis of

  15. Low-Dose and Standard-Dose Unenhanced Helical Computed Tomography for the Assessment of Acute Renal Colic: Prospective Comparative Study

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Bong Soo; Hwang, Im Kyung; Choi, Yo Won; Namkung, Sook; Kim, Heung Cheol; Hwang, Woo Cheol; Choi, Kuk Myung; Park, Ji Kang; Han, Tae Il; Kang, Weechang [Cheju National Univ. College of Medicine, Jeju (Korea, Republic of). Dept. of Diagnostic Radiology

    2005-11-01

    Purpose: To compare the efficacy of low-dose and standard-dose computed tomography (CT) for the diagnosis of ureteral stones. Material and Methods: Unenhanced helical CT was performed with both a standard dose (260 mAs, pitch 1.5) and a low dose (50 mAs, pitch 1.5) in 121 patients suspected of having acute renal colic. The two studies were prospectively and independently interpreted for the presence and location of ureteral stones, abnormalities unrelated to stone disease, identification of secondary signs, i.e. hydronephrosis and perinephric stranding, and tissue rim sign. The standard-dose CT images were interpreted by one reviewer and the low-dose CT images independently by two reviewers unaware of the standard-dose CT findings. The findings of the standard and low-dose CT scans were compared with the exact McNemar test. Interobserver agreements were assessed with kappa analysis. The effective radiation doses resulting from two different protocols were calculated by means of commercially available software to which the Monte-Carlo phantom model was given. Results: The sensitivity, specificity, and accuracy of standard-dose CT for detecting ureteral stones were 99%, 93%, and 98%, respectively, whereas for the two reviewers the sensitivity of low-dose CT was 93% and 95%, specificity 86%, and accuracy 92% and 94%. We found no significant differences between standard-dose and low-dose CT in the sensitivity and specificity for diagnosing ureter stones ( P >0.05 for both). However, the sensitivity of low-dose CT for detection of 19 stones less than or equal to 2 mm in diameter was 79% and 68%, respectively, for the two reviewers. Low-dose CT was comparable to standard-dose CT in visualizing hydronephrosis and the tissue rim sign. Perinephric stranding was far less clear on low-dose CT. Low-dose CT had the same diagnostic performance as standard-dose CT in diagnosing alternative diseases. Interobserver agreement between the two low-dose CT reviewers in the diagnosis of

  16. Quantitative Image Quality Comparison of Reduced- and Standard-Dose Dual-Energy Multiphase Chest, Abdomen, and Pelvis CT.

    Science.gov (United States)

    Buty, Mario; Xu, Ziyue; Wu, Aaron; Gao, Mingchen; Nelson, Chelyse; Papadakis, Georgios Z; Teomete, Uygar; Celik, Haydar; Turkbey, Baris; Choyke, Peter; Mollura, Daniel J; Bagci, Ulas; Folio, Les R

    2017-06-01

    We present a new image quality assessment method for determining whether reducing radiation dose impairs the image quality of computed tomography (CT) in qualitative and quantitative clinical analyses tasks. In this Institutional Review Board-exempt study, we conducted a review of 50 patients (male, 22; female, 28) who underwent reduced-dose CT scanning on the first follow-up after standard-dose multiphase CT scanning. Scans were for surveillance of von Hippel-Lindau disease (N = 26) and renal cell carcinoma (N = 10). We investigated density, morphometric, and structural differences between scans both at tissue (fat, bone) and organ levels (liver, heart, spleen, lung). To quantify structural variations caused by image quality differences, we propose using the following metrics: dice similarity coefficient, structural similarity index, Hausdorff distance, gradient magnitude similarity deviation, and weighted spectral distance. Pearson correlation coefficient and Welch 2-sample t test were used for quantitative comparisons of organ morphometry and to compare density distribution of tissue, respectively. For qualitative evaluation, 2-sided Kendall Tau test was used to assess agreement among readers. Both qualitative and quantitative evaluations were designed to examine significance of image differences for clinical tasks. Qualitative judgment served as an overall assessment, whereas detailed quantifications on structural consistency, intensity homogeneity, and texture similarity revealed more accurate and global difference estimations. Qualitative and quantitative results indicated no significant image quality degradation. Our study concludes that low(er)-dose CT scans can be routinely used because of no significant loss in quantitative image information compared with standard-dose CT scans.

  17. The need for international standardization in clinical beta dosimetry for brachytherapy

    International Nuclear Information System (INIS)

    Quast, U.; Boehm, J.; Kaulich, T.W.

    2002-01-01

    Beta radiation has found increasing interest in radiotherapy. Besides the curative treatment of small and medium-sized intraocular tumors by means of ophthalmic beta radiation plaques, intravascular brachytherapy has proven to successfully overcome the severe problem of restenosis after interventional treatment of arterial stenosis in coronaries and peripheral vessels in many clinical trials with a large number of patients. Prior to initiating procedures applying beta radiation in radiotherapy, however, there is a common need to specify methods for the determination and specification of the absorbed dose to water or tissue and their spatial distributions. The IAEA-TECDOC-1274 Calibration of photon and beta ray sources used in brachytherapy (2002) is a help for photon brachytherapy calibration. But, for beta seed and line sources, IAEA recommends well type ionization chambers as working standards which are far from measuring absorbed dose to water of the radiation clinically used. Although the application of such working standards seems to be more precise, large errors can occur when the medical physicist has to convert the calibration data to absorbed dose to water of the beta radiation emitted. The user must believe that the source is equally activated and that the manufacturer did not change the design and construction of the source encapsulation. With the DGMP Report 16 (2001) Guidelines for medical physical aspects of intravascular brachytherapy a very detailed code of practice is given, especially for the calibration and clinical dosimetry of intravascular beta radiation sources. As there is a global need for standardization in clinical dosimetry for intravascular brachytherapy utilizing beta radiation, the DIN-NAR, the German committee on standardization in radiology, task group dosimetry, has initiated an international adhoc working group for a new ISO work item proposal on the standardization of procedures in clinical dosimetry to guarantee reliable

  18. Feasibility study on standardization of 131I dose in hyperthyrodisom treatment

    International Nuclear Information System (INIS)

    Tang Yi

    2011-01-01

    To explore feasibility of standardization of 131 I dose in Graves' hyperthyroidism treatment, the data of 681 Graves' disease cases treated with 131 I was retrospective studied. The software was developed to re-calculate the 131 I doses for the patients and compared with original doses given by traditional method. 313 patients with complete information were taken and divided to three groups base on the remedial effect, Cured Group (123 patients), Uncured Group (125 patients) and Hypothyroid Group (65 patients). The results showed that there was no statistically significant difference between the 131 I dose for Graves' hyperthyroidism treatment calculated by two methods (P>0.05). There was obviously statistically significant difference in hypothyroid Group (P 131 I calculated by software method (174.27 MBq) was less than that of traditional method (190.18 MBq). In uncured group, there was still obviously statistically significant difference (P 131 I calculated by software method (187.22 MBq) was more than that of the traditional method (169.46 MBq). In cured group, there was no statistically significant difference (P>0.005), the mean dose of 131 I calculated by software method (185 MBq) was slightly smaller than that of the traditional method(192.03 MBq). The results indicate the calculation of standard 131 I dose for Graves' hyperthyroidism treatment by software developed in this study is feasible. (authors)

  19. The 1997 determination of the Australian standards of exposure and absorbed dose at 60Co

    International Nuclear Information System (INIS)

    Huntley, R.B.; Boas, J.F.; Van der Gaast, H.

    1998-05-01

    The arrangements for the maintenance of the Australian standards for 60 Co are described in detail. The primary standards are a graphite cavity chamber for exposure/air kerma and a graphite calorimeter for absorbed dose. These secondary standards are described and their responses in corresponding 90 Sr reference sources are reported. Accurate ratios between the Australian Radiation Laboratory (ARL) and Australian Nuclear Science and Technology (ANSTO) 90 Sr reference sources are derived for use in future calibrations. The value of 28.8 years for the half-life of 90 Sr is confirmed. The usefulness of 90 Sr reference source measurements in quality assurance is discussed. The charge sensitivity and linearity of the ANSTO electrometers are reported by two different methods and are compared with previous results. Calibration factors for all the secondary standard ionization chambers are given, in terms of exposure, air kerma and absorbed dose to water. Calibration factors are also given for most of the chambers in terms of absorbed dose to graphite. The methods of deriving the calibration factors are explained in detail, including all the corrections applied to both the primary and secondary standard measurements. Three alternative methods of deriving the absorbed dose to water calibration factors are compared. The reported calibration factors are compared with previous results. Changes in the Australian units of exposure, air kerma and absorbed dose to graphite and water are derived from changes in the corresponding calibration factors. The Australian units of exposure and air kerma have not changed significantly since 1990. The Australian unit of absorbed dose to graphite is now 1.1 % smaller than in 1993 and 1.3 % smaller than in 1990. The Australian unit of absorbed dose to water is now 1.4 % smaller than in 1993, but is only 0.9 % smaller than in 1990. Comparisons of the Australian standards of exposure/air kerma and absorbed dose with those of the Bureau

  20. The 1997 determination of the Australian standards of exposure and absorbed dose at {sup 60}Co

    Energy Technology Data Exchange (ETDEWEB)

    Huntley, R.B.; Boas, J.F. [Australian Radiation Laboratory, Yallambie, VIC (Australia); Van der Gaast, H. [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia)

    1998-05-01

    The arrangements for the maintenance of the Australian standards for {sup 60}Co are described in detail. The primary standards are a graphite cavity chamber for exposure/air kerma and a graphite calorimeter for absorbed dose. These secondary standards are described and their responses in corresponding {sup 90}Sr reference sources are reported. Accurate ratios between the Australian Radiation Laboratory (ARL) and Australian Nuclear Science and Technology (ANSTO) {sup 90}Sr reference sources are derived for use in future calibrations. The value of 28.8 years for the half-life of {sup 90}Sr is confirmed. The usefulness of {sup 90}Sr reference source measurements in quality assurance is discussed. The charge sensitivity and linearity of the ANSTO electrometers are reported by two different methods and are compared with previous results. Calibration factors for all the secondary standard ionization chambers are given, in terms of exposure, air kerma and absorbed dose to water. Calibration factors are also given for most of the chambers in terms of absorbed dose to graphite. The methods of deriving the calibration factors are explained in detail, including all the corrections applied to both the primary and secondary standard measurements. Three alternative methods of deriving the absorbed dose to water calibration factors are compared. The reported calibration factors are compared with previous results. Changes in the Australian units of exposure, air kerma and absorbed dose to graphite and water are derived from changes in the corresponding calibration factors. The Australian units of exposure and air kerma have not changed significantly since 1990. The Australian unit of absorbed dose to graphite is now 1.1 % smaller than in 1993 and 1.3 % smaller than in 1990. The Australian unit of absorbed dose to water is now 1.4 % smaller than in 1993, but is only 0.9 % smaller than in 1990. Comparisons of the Australian standards of exposure/air kerma and absorbed dose with

  1. Contribution to the determination of a standard of absorbed dose in water for cobalt 60 photons

    International Nuclear Information System (INIS)

    Zitouni, Y.

    1986-07-01

    A new standard, expressed in terms of absorbed dose at a depth of 5g/cm 2 in a water phantom irradiated by cobalt 60 gamma photons, is determined. The procedure developed is based on a transfer method using two dosimetric techniques: Fricke dosimetry and ionometry (0.6 cm 3 NE 2571 radiotherapy ionization chamber). Their calibration is performed with the primary calibration standard of absorbed dose: the graphite calorimeter. The relative discrepancy between the values of absorbed dose in water determined by the chemical dosimeter and the ionization chamber is equal to 1%. The ionization chamber has been also calibrated near the Cobalt 60 reference beam characterized in terms of air kerma [fr

  2. Amodiaquine-associated adverse effects after inadvertent overdose and after a standard therapeutic dose

    DEFF Research Database (Denmark)

    Adjei, G O; Goka, B Q; Rodrigues, O P

    2009-01-01

    A case of an acute dystonic reaction in a child presumptively treated for malaria with amodiaquine, and a case of persistent asymptomatic bradycardia in another child with mild pulmonary stenosis treated with a standard dose of amodiaquine for parasitologically confirmed uncomplicated malaria, is...

  3. Organizational, technical, physical and clinical quality standards for radiotherapy

    Science.gov (United States)

    Bogusz-Czerniewicz, Marta; Kaźmierczak, Daniel

    2012-01-01

    Background Indisputably, radiotherapy has become an entirely interdisciplinary specialty. This situation requires efficient planning, verification, monitoring, quality control and constant improvement of all aspects of service delivery, referring both to patients’ (including diagnosis, prescription and method of treatment, its justification, realization and follow up) and organizational, technical and physics matters. Aim The aim of this work was to develop technical, physics and clinical quality standards for radiotherapy. This paper presents chosen standards for each of the aforementioned category. Materials and methods For the development of quality standards the comparison analysis of EU and Polish acts of law passed between 1980 and 2010 was conducted, the universal industrial ISO norm 9001:2008 referring to quality management system was reviewed. Recommendations of this norm were completed with detailed quality standards based on the author's 11 year work experience and the review of articles on quality assurance and quality control standards for radiotherapy published between 1984 and 2009 and the review of current recommendations and guidelines of American, International, European and National bodies (associations, societies, agencies such as AAPM, ESTRO, IAEA, and OECI) for quality assurance and quality management in radiotherapy. Results As a result 352 quality standards for radiotherapy were developed and categorized into the following three groups: (1) organizational standards, (2) physics and technical standards and (3) clinical standards. Conclusions Proposed quality standards for radiotherapy, can be used by any institution using ionizing radiation for medical procedures. Nevertheless standards are only of value if they are implemented, reviewed, audited and improved and if there is a clear mechanism in place to monitor and address failure to meet agreed standards. PMID:24377023

  4. The provision of national standards of absorbed dose for radiation processing. The role of NPL in the United Kingdom

    International Nuclear Information System (INIS)

    Ellis, S.C.

    1981-01-01

    The system of national and international standardization is examined, particularly with respect to the problems of standardizing high absorbed dose measurements required in processing with photons from cobalt-60 and electrons. The need for development of primary standards specifically dedicated to this application versus the possibility of extrapolation from standards in use at lower dose levels is considered together with means for dissemination and intercomparison. The present status of standards at NPL and the future programme are outlined. (author)

  5. Clinical practitioners' knowledge of ionizing radiation doses in ...

    African Journals Online (AJOL)

    Background: Observation has shown a preponderance of irrelevant, unjustified and perhaps unnecessary radiological requests in the study area. The consequences of this on the patients' doses and population collective dose may be dire. Objective: To assess Clinicians/Referrers' knowledge of radiation doses of patients ...

  6. Dependence of alanine gel dosimeter response as a function of photon clinical beams dose rate

    International Nuclear Information System (INIS)

    Silva, Cleber Feijo; Campos, Leticia Lucente

    2013-01-01

    Gel dosimetry is a new area developed by Gore, it is ery useful for application in radiotherapy because using NMR imaging as evaluation technique is possible to evaluate three dimensional absorbed dose distribution. The measure technique is based on difference of ferrous (Fe 2+ ) and ferric (Fe 3+ ) ) ions concentration that can be measured also by spectrophotometry technique. The Alanine gel dosimeter was developed at IPEN. The alanine is an amino acid and tissue equivalent material that presents significant improvement on previous alanine dosimetry systems. The addition of Alanine increases the production of ferric ions in the solution. This work aims to study the dose rate dependence of photon clinical beams radiation on the alanine gel dosimeter optical response, as well as the response repeatability and gel production reproducibility, since this property is very important for characterization and standardization of any dosimeter. (author)

  7. CCRI supplementary comparison of standards for absorbed dose to water in {sup 60}Co gamma radiation at radiation processing dose levels

    Energy Technology Data Exchange (ETDEWEB)

    Burns, D.T. [Bureau International des Poids et Mesures, Pavillon de Breteuil, F-92312 Sevres Cedex (France)]. E-mail: dburns@bipm.org; Allisy-Roberts, P.J. [Bureau International des Poids et Mesures, Pavillon de Breteuil, F-92312 Sevres Cedex (France); Desrosiers, M.F. [National Institute of Standards and Technology, Gaithersburg, MD (United States); Nagy, V.Yu. [National Institute of Standards and Technology, Gaithersburg, MD (United States); Sharpe, P.H.G. [National Physical Laboratory, Teddington, Middlesex (United Kingdom); Laitano, R.F. [Istituto Nazionale di Metrologia delle Radiazioni Ionizzanti, Rome (Italy); Mehta, K. [International Atomic Energy Agency, Vienna (Austria); Schneider, M.K.H. [Physikalisch-Technische Bundesanstalt, Braunschweig (Germany); Zhang, Y.L. [National Institute of Metrology, Beijing (China)

    2006-09-15

    Six national standards for absorbed dose to water in {sup 60}Co gamma radiation at the dose levels used in radiation processing have been compared over the range from 5 to 30 kGy using the alanine dosimeters of the NIST and the NPL as the transfer dosimeters. The standards are in agreement at the level of around 0.5%, which is significantly smaller than the stated standard uncertainties.

  8. Cone beam CT paranasal sinuses versus standard multidetector and low dose multidetector CT studies.

    Science.gov (United States)

    Al Abduwani, Janan; ZilinSkiene, Laura; Colley, Steve; Ahmed, Shahzada

    2016-01-01

    Cone-beam computed tomography (CBCT) is a promising modality for quick outpatient imaging with lower radiation dose and less metal artifact when compared to conventional CT (MDCT) scans. This article will be providing evidence on the diagnostic and treatment-planning applications of CBCT in sinus imaging, mainly, in patients with chronic sinusitis for surgical planning, which retrospectively assessed 21 patients over a period of one year at Queen Elisabeth Hospital, Birmingham, UK. The main objective was to compare the absorbed dose of radiation from CBCT and conventional CT, and to compare the clarity and image quality for important structures in sinus anatomy in patients with sinus disease meriting CT scan imaging. Results of the mean effective dose of twenty-one consecutive CBCTs of paranasal sinuses were 0.27 mSv (range 0.05-0.48 mSv). This dose was approximately 40% lower when compared to a similar cohort of standard MDCT examinations and 30% lower when compared to low dose sinus CT scans. The visualization of high-contrast bone morphology on CBCT was comparable to standard sinus CT, allowing clear delineation of the principal surgically relevant osseous structures. Soft tissue visibility was however limited. We concluded that, CBCT scan provides a fast and efficient alternative to conventional CT with substantial radiation dose reduction and low dose MDCT techniques. However for more advanced sinus disease, conventional CT scan is preferable. The main objective was to compare the absorbed dose in the cone beam computed tomography (CBCT) and conventional CT and to compare the clarity and image quality for important structures in sinus anatomy. Retrospective scan review. We compared both the image characteristics and the effective dose used in CBCT and conventional MDCT sinus imaging, performed at Queen Elizabeth Hospital Birmingham over a 1 year period. Patient with sinus disease meriting CT scan imaging. Comparison of effective dose exposure and image quality

  9. Prospective evaluation of reduced dose computed tomography for the detection of low-contrast liver lesions. Direct comparison with concurrent standard dose imaging

    Energy Technology Data Exchange (ETDEWEB)

    Pooler, B.D.; Lubner, Meghan G.; Kim, David H.; Chen, Oliver T. [University of Wisconsin School of Medicine and Public Health, Department of Radiology, Madison, WI (United States); Li, Ke; Chen, Guang-Hong [University of Wisconsin School of Medicine and Public Health, Department of Radiology, Madison, WI (United States); University of Wisconsin School of Medicine and Public Health, Department of Medical Physics, Madison, WI (United States); Pickhardt, Perry J. [University of Wisconsin School of Medicine and Public Health, Department of Radiology, Madison, WI (United States); University of Wisconsin School of Medicine and Public Health, E3/311 Clinical Science Center, Department of Radiology, Madison, WI (United States)

    2017-05-15

    To prospectively compare the diagnostic performance of reduced-dose (RD) contrast-enhanced CT (CECT) with standard-dose (SD) CECT for detection of low-contrast liver lesions. Seventy adults with non-liver primary malignancies underwent abdominal SD-CECT immediately followed by RD-CECT, aggressively targeted at 60-70 % dose reduction. SD series were reconstructed using FBP. RD series were reconstructed with FBP, ASIR, and MBIR (Veo). Three readers - blinded to clinical history and comparison studies - reviewed all series, identifying liver lesions ≥4 mm. Non-blinded review by two experienced abdominal radiologists - assessing SD against available clinical and radiologic information - established the reference standard. RD-CECT mean effective dose was 2.01 ± 1.36 mSv (median, 1.71), a 64.1 ± 8.8 % reduction. Pooled per-patient performance data were (sensitivity/specificity/PPV/NPV/accuracy) 0.91/0.78/0.60/0.96/0.81 for SD-FBP compared with RD-FBP 0.79/0.75/0.54/0.91/0.76; RD-ASIR 0.84/0.75/0.56/0.93/0.78; and RD-MBIR 0.84/0.68/0.49/0.92/0.72. ROC AUC values were 0.896/0.834/0.858/0.854 for SD-FBP/RD-FBP/RD-ASIR/RD-MBIR, respectively. RD-FBP (P = 0.002) and RD-MBIR (P = 0.032) AUCs were significantly lower than those of SD-FBP; RD-ASIR was not (P = 0.052). Reader confidence was lower for all RD series (P < 0.001) compared with SD-FBP, especially when calling patients entirely negative. Aggressive CT dose reduction resulted in inferior diagnostic performance and reader confidence for detection of low-contrast liver lesions compared to SD. Relative to RD-ASIR, RD-FBP showed decreased sensitivity and RD-MBIR showed decreased specificity. (orig.)

  10. MDCT for suspected acute appendicitis in adults: impact of oral and IV contrast media at standard-dose and simulated low-dose techniques.

    Science.gov (United States)

    Keyzer, Caroline; Cullus, Pierre; Tack, Denis; De Maertelaer, Viviane; Bohy, Pascale; Gevenois, Pierre Alain

    2009-11-01

    The objective of this study was to prospectively investigate the influence of oral, IV, and oral and IV contrast media on the information provided by MDCT at standard and simulated low radiation doses in adults suspected of having acute appendicitis. One hundred thirty-one consecutive patients (80 women, 51 men; age range, 18-87 years; mean age, 37 years) suspected of having appendicitis were randomly assigned to either ingest or not ingest iodinated contrast material. Thereafter, all patients underwent IV unenhanced and enhanced abdominopelvic MDCT with a 4 x 2.5 mm collimation at 120 kVp and 100 mAs(eff). Dose reduction corresponding to 30 mAs(eff) was simulated. Two radiologists independently read scans during separate sessions, assessed appendix visualization, and proposed a diagnosis (i.e., appendicitis or an alternative diagnosis). The final diagnosis was based on either surgical findings or clinical follow-up. Data were analyzed by factorial analysis of multiple correspondences followed by an ascending hierarchic classification method. Factorial analysis and ascending hierarchic classification revealed that, in terms of diagnostic correctness, reader influence predominated over the influence of IV and oral contrast media use and radiation dose but that correctness was also influenced by the patient's sex (p = 0.048) and was lower in cases of alternative diseases (p technique.

  11. Clinical application of a OneDose(TM) MOSFET for skin dose measurements during internal mammary chain irradiation with high dose rate brachytherapy in carcinoma of the breast

    International Nuclear Information System (INIS)

    Kinhikar, Rajesh A; Sharma, Pramod K; Tambe, Chandrashekhar M; Mahantshetty, Umesh M; Sarin, Rajiv; Deshpande, Deepak D; Shrivastava, Shyam K

    2006-01-01

    In our earlier study, we experimentally evaluated the characteristics of a newly designed metal oxide semiconductor field effect transistor (MOSFET) OneDose(TM) in-vivo dosimetry system for Ir-192 (380 keV) energy and the results were compared with thermoluminescent dosimeters (TLDs). We have now extended the same study to the clinical application of this MOSFET as an in-vivo dosimetry system. The MOSFET was used during high dose rate brachytherapy (HDRBT) of internal mammary chain (IMC) irradiation for a carcinoma of the breast. The aim of this study was to measure the skin dose during IMC irradiation with a MOSFET and a TLD and compare it with the calculated dose with a treatment planning system (TPS). The skin dose was measured for ten patients. All the patients' treatment was planned on a PLATO treatment planning system. TLD measurements were performed to compare the accuracy of the measured results from the MOSFET. The mean doses measured with the MOSFET and the TLD were identical (0.5392 Gy, 15.85% of the prescribed dose). The mean dose was overestimated by the TPS and was 0.5923 Gy (17.42% of the prescribed dose). The TPS overestimated the skin dose by 9% as verified by the MOSFET and TLD. The MOSFET provides adequate in-vivo dosimetry for HDRBT. Immediate readout after irradiation, small size, permanent storage of dose and ease of use make the MOSFET a viable alternative for TLDs. (note)

  12. HALF-DOSE DEPOT TRIPTORELIN COMPARABLE TO REDUCED DAILY BUSERELIN: A RANDOMIZED CLINICAL TRIAL

    Directory of Open Access Journals (Sweden)

    L. Safdarian

    2007-09-01

    Full Text Available Pituitary suppression by depot GnRH agonist may be excessive for ovarian stimulation. This study compares the efficacy of a single half-dose depot triptorelin and reduced-dose daily buserelin in a long protocol ICSI/ET. METHODS: A total of 182 patients were randomized into two groups using sealed envelopes. Pituitary desensitization was obtained in group 1 (91 patients with half-dose (1.87 mg depot triptorelin in the mid-luteal phase of their menstrual cycle, and in group 2 (91 patients with standard daily dose (0.5 mg buserelin, which was then reduced to 0.25 mg at the start of human menopausal gonadotropin (HMG stimulation. RESULTS: No significant differences were found among those who received HCG in terms of clinical pregnancy rate (34.4% in both groups, implantation rate (14.8% in group 1 versus 11.1% in group 2, fertilization rate (93.3 versus 95.6%, poor response rate (11.1 versus 6.7%, and miscarriage rate (11.1 versus 7.8%. No significant differences were seen in number of HMG ampoules used, follicles at HCG administration, and oocytes retrieved. The number of days of stimulation was significantly reduced in group 2 (11.2 +/- 1.8 in group 1 versus 10.6 +/- 1.9, p = 0.030. CONCLUSION: A half-dose of depot triptorelin can be successfully used in ovarian stimulation instead of reduced-dose daily buserelin, with more patient comfort and reduced stress and cost of injections.

  13. Symptom-triggered benzodiazepine therapy for alcohol withdrawal syndrome in the emergency department: a comparison with the standard fixed dose benzodiazepine regimen.

    LENUS (Irish Health Repository)

    Cassidy, Eugene M

    2012-10-01

    The aim of the study was to compare symptom-triggered and standard benzodiazepine regimens for the treatment of alcohol withdrawal syndrome in an emergency department clinical decision unit. The authors found that the symptom-triggered approach reduced cumulative benzodiazepine dose and length of stay.

  14. Unenhanced low-dose versus standard-dose CT localization in patients with upper urinary calculi for minimally invasive percutaneous nephrolithotomy (MPCNL).

    Science.gov (United States)

    Licheng, Jiang; Yidong, Fan; Ping, Wang; Keqiang, Yan; Xueting, Wang; Yingchen, Zhang; Lei, Gao; Jiyang, Ding; Zhonghua, Xu

    2014-03-01

    With the ethical concern about the dose of CT scan and wide use of CT in protocol of suspected renal colic, more attention has been paid to low dose CT. The aim of the present study was to make a comparison of unenhanced low-dose spiral CT localization with unenhanced standard-dose spiral CT in patients with upper urinary tract calculi for minimally invasive percutaneous nephrolithotomy (MPCNL) treatment. Twenty eight patients with ureter and renal calculus, preparing to take MPCNL, underwent both abdominal low-dose CT (25 mAs) and standard-dose CT (100 mAs). Low-dose CT and standard-dose CT were independently evaluated for the characterization of renal/ureteral calculi, perirenal adjacent organs, blood vessels, indirect signs of renal or ureteral calculus (renal enlargement, pyeloureteral dilatation), and the indices of localization (percutaneous puncture angulation and depth) used in the MPCNL procedure. In all 28 patients, low-dose CT was 100 per cent coincidence 100 per cent sensitive and 100 per cent specific for depicting the location of the renal and ureteral calculus, renal enlargement, pyeloureteral dilatation, adjacent organs, and the presumptive puncture point and a 96.3 per cent coincidence 96 per cent sensitivity and 93 per cent specificity for blood vessel signs within the renal sinus, and with an obvious lower radiation exposure for patients when compared to standard-dose CT (Plow-dose CT achieves a sensitivity and accuracy similar to that of standard-dose CT in assessing the localization of renal ureteral calculus and adjacent organs conditions and identifying the maximum calculus transverse diameter on the axial surface, percutaneous puncture depth, and angulation in patients, with a significant lower radiation exposure, who are to be treated by MPCNL, and can be used as an alternative localization method.

  15. Clinical perceptions of radiation therapy undergraduate competency standards.

    Science.gov (United States)

    Carmichael, Mary-Ann; Bridge, Pete

    2014-12-01

    The multifactorial nature of clinical skills development makes assessment of undergraduate radiation therapist competence level by clinical mentors challenging. A recent overhaul of the clinical assessment strategy at Queensland University of Technology has moved away from the high-stakes Objective Structured Clinical Examination (OSCE) to encompass a more continuous measure of competence. This quantitative study aimed to gather stakeholder evidence to inform development of standards by which to measure student competence for a range of levels of progression. A simple anonymous questionnaire was distributed to all Queensland radiation therapists. The tool asked respondents to assign different levels of competency with a range of clinical tasks to different levels of student. All data were anonymous and was combined for analysis using Microsoft Excel. Feedback indicated good agreement with tasks that specified the amount of direction required and this has been incorporated into the new clinical achievements record that the students need to have signed off. Additional puzzling findings suggested higher expectations with planning tasks than with treatment-based tasks. The findings suggest that the amount of direction required by students is a valid indicator of their level and has been adopted into the clinical assessment scheme. Further work will build on this to further define standards of competency for undergraduates.

  16. Extension of the Commonwealth standard of absorbed dose from cobalt-60 energy to 25 MV

    International Nuclear Information System (INIS)

    Sherlock, S.L.

    1986-01-01

    With the introduction of high energy linear accelerators in hospitals, there is a need for direct measurement of absorbed dose for energies to 25 MV for photons and 20 MeV electrons. The present Australian standard for absorbed dose at cobalt-60 energy is a graphite micro-calorimeter maintained at the AAEC Lucas Heights Research Laboratories. A thorough theoretical analysis of calorimeter operation suggests that computer control and monitoring techniques are appropriate. Solution of Newton's law of cooling for a four-body calorimeter allows development of a computer simulation model. Different temperature control algorithms may then be run and assessed using this model. In particular, the application of a simple differencer is examined. Successful implementation of the calorimeter for energies up to 25 MV could lead to the introduction of an Australian absorbed dose protocol based on calorimetry, therby reducing the uncertainties associated with exposure-based protocols

  17. WE-F-BRB-01: The Power of Ontologies and Standardized Terminologies for Capturing Clinical Knowledge

    International Nuclear Information System (INIS)

    Gabriel, P.

    2015-01-01

    Advancements in informatics in radiotherapy are opening up opportunities to improve our ability to assess treatment plans. Models on individualizing patient dose constraints from prior patient data and shape relationships have been extensively researched and are now making their way into commercial products. New developments in knowledge based treatment planning involve understanding the impact of the radiation dosimetry on the patient. Akin to radiobiology models that have driven intensity modulated radiotherapy optimization, toxicity and outcome predictions based on treatment plans and prior patient experiences may be the next step in knowledge based planning. In order to realize these predictions, it is necessary to understand how the clinical information can be captured, structured and organized with ontologies and databases designed for recall. Large databases containing radiation dosimetry and outcomes present the opportunity to evaluate treatment plans against predictions of toxicity and disease response. Such evaluations can be based on dose volume histogram or even the full 3-dimensional dose distribution and its relation to the critical anatomy. This session will provide an understanding of ontologies and standard terminologies used to capture clinical knowledge into structured databases; How data can be organized and accessed to utilize the knowledge in planning; and examples of research and clinical efforts to incorporate that clinical knowledge into planning for improved care for our patients. Learning Objectives: Understand the role of standard terminologies, ontologies and data organization in oncology Understand methods to capture clinical toxicity and outcomes in a clinical setting Understand opportunities to learn from clinical data and its application to treatment planning Todd McNutt receives funding from Philips, Elekta and Toshiba for some of the work presented

  18. Dose reduction in abdominal computed tomography: intraindividual comparison of image quality of full-dose standard and half-dose iterative reconstructions with dual-source computed tomography.

    Science.gov (United States)

    May, Matthias S; Wüst, Wolfgang; Brand, Michael; Stahl, Christian; Allmendinger, Thomas; Schmidt, Bernhard; Uder, Michael; Lell, Michael M

    2011-07-01

    We sought to evaluate the image quality of iterative reconstruction in image space (IRIS) in half-dose (HD) datasets compared with full-dose (FD) and HD filtered back projection (FBP) reconstruction in abdominal computed tomography (CT). To acquire data with FD and HD simultaneously, contrast-enhanced abdominal CT was performed with a dual-source CT system, both tubes operating at 120 kV, 100 ref.mAs, and pitch 0.8. Three different image datasets were reconstructed from the raw data: Standard FD images applying FBP which served as reference, HD images applying FBP and HD images applying IRIS. For the HD data sets, only data from 1 tube detector-system was used. Quantitative image quality analysis was performed by measuring image noise in tissue and air. Qualitative image quality was evaluated according to the European Guidelines on Quality criteria for CT. Additional assessment of artifacts, lesion conspicuity, and edge sharpness was performed. : Image noise in soft tissue was substantially decreased in HD-IRIS (-3.4 HU, -22%) and increased in HD-FBP (+6.2 HU, +39%) images when compared with the reference (mean noise, 15.9 HU). No significant differences between the FD-FBP and HD-IRIS images were found for the visually sharp anatomic reproduction, overall diagnostic acceptability (P = 0.923), lesion conspicuity (P = 0.592), and edge sharpness (P = 0.589), while HD-FBP was rated inferior. Streak artifacts and beam hardening was significantly more prominent in HD-FBP while HD-IRIS images exhibited a slightly different noise pattern. Direct intrapatient comparison of standard FD body protocols and HD-IRIS reconstruction suggest that the latest iterative reconstruction algorithms allow for approximately 50% dose reduction without deterioration of the high image quality necessary for confident diagnosis.

  19. The 1998 calibration of Australian secondary standards of exposure and absorbed dose at 60Co

    International Nuclear Information System (INIS)

    Huntley, R.B.; Van der Gaast, H.

    1998-10-01

    New calibration factors are reported for several of the ionization chambers maintained at the Australian Radiation Laboratory (ARL) and at the Australian Nuclear Science and Technology Organisation (ANSTO) as Australian secondary standards of exposure/air kerma and absorbed dose at 60 Co. These calibration factors supplement or replace the calibration factors given in earlier reports. Updated 90 Sr reference source data are given for the ARL chambers, and for two of the ANSTO chambers. These results confirm the stability of the secondary standards. A re-calibration of the ANSTO reference electrometer is reported. This was carried out using an improved method, which is fully described

  20. Offsite dose calculation manual guidance: Standard radiological effluent controls for boiling water reactors

    International Nuclear Information System (INIS)

    Meinke, W.W.; Essig, T.H.

    1991-04-01

    This report contains guidance which may be voluntarily used by licensees who choose to implement the provision of Generic Letter 89-- 01, which allows Radiological Effluent Technical Specifications (RETS) to be removed from the main body of the Technical Specifications and placed in the Offsite Dose Calculation Manual (ODCM). Guidance is provided for Standard Effluent Controls definitions, Controls for effluent monitoring instrumentation, Controls for effluent releases, Controls for radiological environmental monitoring, and the basis for Controls. Guidance on the formulation of RETS has been available in draft form for a number of years; the current effort simply recasts those RETS into Standard Radiological Effluent Controls for application to the ODCM. 11 tabs

  1. Influence of standard RF coil materials on surface and buildup dose from a 6 MV photon beam in magnetic field.

    Science.gov (United States)

    Ghila, A; Fallone, B G; Rathee, S

    2016-11-01

    Magnetic resonance guided teletherapy systems aspire to image the patient concurrently with the radiation delivery. Thus, the radiofrequency (RF) coils used for magnetic resonance imaging, placed on or close to patient skin and in close proximity to the treatment volume, would be irradiated leading to modifications of radiation dose to the skin and in the buildup region. The purpose of this work is to measure and assess these dose modifications due to standard off-the-shelf RF coil materials. A typical surface coil was approximated as layered sheets of polycarbonate, copper tape, and Teflon to emulate the base, conductor, and cover, respectively. A separate investigation used additional coil materials, such as copper pipe, plastic coil housing, a typical coil padding material, and a thin copper conductor. The materials were placed in the path of a 6 MV photon beam at various distances from polystyrene phantoms in which the surface and buildup doses were measured. The experiments were performed on a clinical Varian linac with no magnetic field and with a 0.21 T electromagnet producing a magnetic field parallel to the beam central axis. The authors repeated similar experiments in the presence of a 0.22 T magnetic field oriented perpendicular to the beam central axis using an earlier linac-MR prototype, with a biplanar permanent magnet. The radiation detectors used for the measurements were two different parallel plate ion chambers and GAFChromic films. A typical open beam surface dose of 20% (relative to open beam D max ) was increased to 63% by the coil padding material and to >74% by all other materials when placed in direct contact with the phantom, irrespective of magnetic field presence or orientation. Without a magnetic field, the surface dose decreased as the test materials were moved away from the phantom surface toward the radiation source, reaching between 30% and 40% at 10 cm gap between the phantom and the test materials. In the presence of the transverse

  2. The Australian Commonwealth standard of measurement for absorbed radiation dose. Part 1

    International Nuclear Information System (INIS)

    Sherlock, S.L.

    1989-08-01

    As an agent for the Commonwealth Scientific and Industrial Research Organisation, the Australian Nuclear Science and Technology Organisation is responsible for maintenance of the Australian Commonwealth standard of absorbed dose. This standard of measurement has application in radiation therapy dosimetry, which is required for the treatment of cancer patients. This report is the first in a series of reports documenting the absorbed dose standard for photon beams in the range from 1 to 25 MeV. The Urquhart graphite micro-calorimeters, which is used for the determination of absorbed dose under high energy photon beams, has been now placed under computer control. Accordingly, a complete upgrade of the calorimeter systems was performed to allow operation in the hospital. In this report, control and monitoring techniques have been described, with an assessment of the performance achieved being given for 6 and 18 MeV bremsstrahlung beams. Random errors have been reduced to near negligible proportions, while systematic errors have been minimized by achieving true quasi-adiabatic operation. 16 refs., 9 tabs., 11 figs

  3. Skin Absorbed Doses from Full Mouth Standard Intraoral Radiography in Bisecting Angle and Paralleling techniques

    Energy Technology Data Exchange (ETDEWEB)

    Nah, Kyung Soo; Kim, Ae Ji [Dept. of Oral Radiology, College of Dentistry, Pusan National University, Pusan (Korea, Republic of); Doh, Shi Hong [Dept. of Applied physics . National Fisheries University of Pusan Department of Radiotherapy, Pusan (Korea, Republic of); Kim, Hyun Ja [Dept. of Oral Radiology, Baptist Hospital, Pusan (Korea, Republic of); Yoo, Meong Jin [Dept. of Radiology, College of Dentistry, Pusan National University, Pusan (Korea, Republic of)

    1990-08-15

    This study was performed to measure the skin absorbed doses from full mouth standard intraoral radiography(14 exposures) in bisecting angle and paralleling techniques. Thermoluminescent dosimeters were used in a phantom. Circular tube collimator (60 mm in diameter, 20 cm in length) and rectangular collimator (35 mm X 44 mm, 40 cm in length) were set for bisecting angle and paralleling techniques respectively. All measurement sites were classified into 8 groups according to distance from each point of central rays. The results were as follows: 1. The skin absorbed doses from the paralleling technique were significantly decreased than those from the bisecting technique in both points at central ray and points away from central ray. The percentage rats of decrease were greater at points away from central ray than those at central ray. 2. The skin absorbed doses at the lens of eye, parotid gland, submandibular gland and thyroid region were significantly decreased in paralleling technique, but those of the midline of palate remained similar in both techniques. 3. The highest doses were measured at the site 20 mm above the point of central ray for the mandibular premolars in bisecting angle technique and at the point of central ray for the mandibular premolars in paralleling techniques. The lowest doses were measured at the thyroid region in both techniques.

  4. Skin Absorbed Doses from Full Mouth Standard Intraoral Radiography in Bisecting Angle and Paralleling techniques

    International Nuclear Information System (INIS)

    Nah, Kyung Soo; Kim, Ae Ji; Doh, Shi Hong; Kim, Hyun Ja; Yoo, Meong Jin

    1990-01-01

    This study was performed to measure the skin absorbed doses from full mouth standard intraoral radiography(14 exposures) in bisecting angle and paralleling techniques. Thermoluminescent dosimeters were used in a phantom. Circular tube collimator (60 mm in diameter, 20 cm in length) and rectangular collimator (35 mm X 44 mm, 40 cm in length) were set for bisecting angle and paralleling techniques respectively. All measurement sites were classified into 8 groups according to distance from each point of central rays. The results were as follows: 1. The skin absorbed doses from the paralleling technique were significantly decreased than those from the bisecting technique in both points at central ray and points away from central ray. The percentage rats of decrease were greater at points away from central ray than those at central ray. 2. The skin absorbed doses at the lens of eye, parotid gland, submandibular gland and thyroid region were significantly decreased in paralleling technique, but those of the midline of palate remained similar in both techniques. 3. The highest doses were measured at the site 20 mm above the point of central ray for the mandibular premolars in bisecting angle technique and at the point of central ray for the mandibular premolars in paralleling techniques. The lowest doses were measured at the thyroid region in both techniques.

  5. International Standardization of the Clinical Dosimetry of Beta Radiation Brachytherapy Sources: Progress of an ISO Standard

    Science.gov (United States)

    Soares, Christopher

    2006-03-01

    In 2004 a new work item proposal (NWIP) was accepted by the International Organization for Standardization (ISO) Technical Committee 85 (TC85 -- Nuclear Energy), Subcommittee 2 (Radiation Protection) for the development of a standard for the clinical dosimetry of beta radiation sources used for brachytherapy. To develop this standard, a new Working Group (WG 22 - Ionizing Radiation Dosimetry and Protocols in Medical Applications) was formed. The standard is based on the work of an ad-hoc working group initiated by the Dosimetry task group of the Deutsches Insitiut für Normung (DIN). Initially the work was geared mainly towards the needs of intravascular brachytherapy, but with the decline of this application, more focus has been placed on the challenges of accurate dosimetry for the concave eye plaques used to treat ocular melanoma. Guidance is given for dosimetry formalisms, reference data to be used, calibrations, measurement methods, modeling, uncertainty determinations, treatment planning and reporting, and clinical quality control. The document is currently undergoing review by the ISO member bodies for acceptance as a Committee Draft (CD) with publication of the final standard expected by 2007. There are opportunities for other ISO standards for medical dosimetry within the framework of WG22.

  6. Determination of the delivered hemodialysis dose using standard methods and on-line clearance monitoring

    Directory of Open Access Journals (Sweden)

    Vlatković Vlastimir

    2006-01-01

    Full Text Available Background/aim: Delivered dialysis dose has a cumulative effect and significant influence upon the adequacy of dialysis, quality of life and development of co-morbidity at patients on dialysis. Thus, a great attention is given to the optimization of dialysis treatment. On-line Clearance Monitoring (OCM allows a precise and continuous measurement of the delivered dialysis dose. Kt/V index (K = dialyzer clearance of urea; t = dialysis time; V = patient's total body water, measured in real time is used as a unit for expressing the dialysis dose. The aim of this research was to perform a comparative assessment of the delivered dialysis dose by the application of the standard measurement methods and a module for continuous clearance monitoring. Methods. The study encompassed 105 patients who had been on the chronic hemodialysis program for more than three months, three times a week. By random choice, one treatment per each controlled patient was taken. All the treatments understood bicarbonate dialysis. The delivered dialysis dose was determined by the calculation of mathematical models: Urea Reduction Ratio (URR singlepool index Kt/V (spKt/V and by the application of OCM. Results. Urea Reduction Ratio was the most sensitive parameter for the assessment and, at the same time, it was in the strongest correlation with the other two, spKt/V indexes and OCM. The values pointed out an adequate dialysis dose. The URR values were significantly higher in women than in men, p < 0.05. The other applied model for the delivered dialysis dose measurement was Kt/V index. The obtained values showed that the dialysis dose was adequate, and that, according to this parameter, the women had significantly better dialysis, then the men p < 0.05. According to the OCM, the average value was slightly lower than the adequate one. The women had a satisfactory dialysis according to this index as well, while the delivered dialysis dose was insufficient in men. The difference

  7. E-health stakeholders experiences with clinical modelling and standardizations.

    Science.gov (United States)

    Gøeg, Kirstine Rosenbeck; Elberg, Pia Britt; Højen, Anne Randorff

    2015-01-01

    Stakeholders in e-health such as governance officials, health IT-implementers and vendors have to co-operate to achieve the goal of a future-proof interoperable e-health infrastructure. Co-operation requires knowledge on the responsibility and competences of stakeholder groups. To increase awareness on clinical modeling and standardization we conducted a workshop for Danish and a few Norwegian e-health stakeholders' and made them discuss their views on different aspects of clinical modeling using a theoretical model as a point of departure. Based on the model, we traced stakeholders' experiences. Our results showed there was a tendency that stakeholders were more familiar with e-health requirements than with design methods, clinical information models and clinical terminology as they are described in the scientific literature. The workshop made it possible for stakeholders to discuss their roles and expectations to each other.

  8. Theoretical analysis of the dose dependence of the oxygen enhancement ratio and its relevance for clinical applications

    International Nuclear Information System (INIS)

    Wenzl, Tatiana; Wilkens, Jan J

    2011-01-01

    The increased resistance of hypoxic cells to ionizing radiation is usually believed to be the primary reason for treatment failure in tumors with oxygen-deficient areas. This oxygen effect can be expressed quantitatively by the oxygen enhancement ratio (OER). Here we investigate theoretically the dependence of the OER on the applied local dose for different types of ionizing irradiation and discuss its importance for clinical applications in radiotherapy for two scenarios: small dose variations during hypoxia-based dose painting and larger dose changes introduced by altered fractionation schemes. Using the widespread Alper-Howard-Flanders and standard linear-quadratic (LQ) models, OER calculations are performed for T1 human kidney and V79 Chinese hamster cells for various dose levels and various hypoxic oxygen partial pressures (pO2) between 0.01 and 20 mmHg as present in clinical situations in vivo. Our work comprises the analysis for both low linear energy transfer (LET) treatment with photons or protons and high-LET treatment with heavy ions. A detailed analysis of experimental data from the literature with respect to the dose dependence of the oxygen effect is performed, revealing controversial opinions whether the OER increases, decreases or stays constant with dose. The behavior of the OER with dose per fraction depends primarily on the ratios of the LQ parameters alpha and beta under hypoxic and aerobic conditions, which themselves depend on LET, pO2 and the cell or tissue type. According to our calculations, the OER variations with dose in vivo for low-LET treatments are moderate, with changes in the OER up to 11% for dose painting (1 or 3 Gy per fraction compared to 2 Gy) and up to 22% in hyper-/hypofractionation (0.5 or 20 Gy per fraction compared to 2 Gy) for oxygen tensions between 0.2 and 20 mmHg typically measured clinically in hypoxic tumors. For extremely hypoxic cells (0.01 mmHg), the dose dependence of the OER becomes more pronounced (up to 36

  9. A review of the clinical experience in pulsed dose rate brachytherapy

    NARCIS (Netherlands)

    Balgobind, Brian V.; Koedooder, Kees; Ordoñez Zúñiga, Diego; Dávila Fajardo, Raquel; Rasch, Coen R. N.; Pieters, Bradley R.

    2015-01-01

    Pulsed dose rate (PDR) brachytherapy is a treatment modality that combines physical advantages of high dose rate (HDR) brachytherapy with the radiobiological advantages of low dose rate brachytherapy. The aim of this review was to describe the effective clinical use of PDR brachytherapy worldwide in

  10. Estimation of the annual cumulative radiation dose received by the dentist in dental clinics in Chennai

    Directory of Open Access Journals (Sweden)

    Sanarpalayam Chinaswamy Selvamuthukumar

    2014-01-01

    Full Text Available Aim and Objectives: To estimate the annual cumulative radiation dose received by a dentist in a ′less than an ideally sized clinic′ in Chennai. The objective of the study is to estimate the annual cumulative radiation dose received by the dentist at various distances and various angulations from the x-ray tube. Study Design: The head of a mannequin model was mounted on the dental chair to simulate a patient′s head and three thermoluminescent dosimeter (TLD chips were kept at various distances and various angulations, at a constant height. The standard conventional intraoral dental radiographic unit was used, which was kept stationary, with a constant voltage of 70 Kv, 8 mA current, and a constant exposure time of 0.3 seconds. Ninety-two TLD chips were exposed 20 times a day with constant horizontal angulations for a period of one year. The reading from the TLD chips was obtained on a computer through a TLD Badge Reader. Statistical Analysis: Post Hoc tests and One-way analysis of variance (ANOVA were used. Results and Conclusion: A decreasing trend was obtained in the average radiation doses, as the distance increased from the x-ray source, and a highly significant difference in doses (P < 0.001% was found between 4 and 5.5 feet (ft. We found a minimum average radiation dose at an angle of 60° to 80° and behind the tube. The purpose of this study was to create awareness among dental professionals, who had ′less than an ideally sized clinic′. We recommend that the dentist follow guidelines suggested by the National Council on Radiation Protection and Measurements (NCRP, USA. From this study, it is clear that most clinics are of sizes that do not permit this distance (6 ft, and hence, it is recommended that they use suitable barriers.

  11. Post-processing image filtration enabling dose reduction in standard abdominal CT.

    Science.gov (United States)

    Leander, Peter; Söderberg, Marcus; Fält, Tobias; Gunnarsson, Mikael; Albertsson, Ida

    2010-01-01

    The collective effective radiation dose to the population is increasing due to a higher use of computerised tomography. SharpView AB, Linköping, Sweden, has developed an adaptive non-linear post-processing image filtration that may enable the use of lower radiation doses. The present study assessed if a lower dose with image filtration had the same image quality as a higher dose without the filter applied. All imaging was performed on a Siemens Somatom Sensation 16 CT. The parameters used were 120 kV and 200 mAs (40 patients) and 130 mAs without and with image filtering (40 patients), respectively. All studies were quantitatively evaluated for noise and image quality was assessed by visual grading characteristics (VGC) analysis. After image filtration, the noise in the processed images was lowered and the image quality was improved as shown by the VGC analysis. However, images using the higher dose were still ranked as the best in five out of eight criteria as shown by the VGC analysis. Image filtration enhances CT images significantly and further studies will show if 130 mAs with image filtration may be sufficient for clinically general abdominal CT.

  12. Standardized Representation of Clinical Study Data Dictionaries with CIMI Archetypes.

    Science.gov (United States)

    Sharma, Deepak K; Solbrig, Harold R; Prud'hommeaux, Eric; Pathak, Jyotishman; Jiang, Guoqian

    2016-01-01

    Researchers commonly use a tabular format to describe and represent clinical study data. The lack of standardization of data dictionary's metadata elements presents challenges for their harmonization for similar studies and impedes interoperability outside the local context. We propose that representing data dictionaries in the form of standardized archetypes can help to overcome this problem. The Archetype Modeling Language (AML) as developed by the Clinical Information Modeling Initiative (CIMI) can serve as a common format for the representation of data dictionary models. We mapped three different data dictionaries (identified from dbGAP, PheKB and TCGA) onto AML archetypes by aligning dictionary variable definitions with the AML archetype elements. The near complete alignment of data dictionaries helped map them into valid AML models that captured all data dictionary model metadata. The outcome of the work would help subject matter experts harmonize data models for quality, semantic interoperability and better downstream data integration.

  13. Comparison of the standards for absorbed dose to water of the ARPANSA and the BIPM for 60Co γ radiation

    International Nuclear Information System (INIS)

    Allisy-Roberts, P.J.; Burns, D.T.; Boas, J.F.; Huntley, R.B.; Wise, K.N.

    2000-10-01

    A comparison of the standards for absorbed dose to water of the Australian Radiation Protection and Nuclear Safety Agency and of the Bureau International des Poids et Mesures (BIPM) has been carried out in 60 Co gamma radiation. The Australian standard is based on a graphite calorimeter and the subsequent conversion from absorbed dose to graphite to absorbed dose to water using the photon fluence scaling theorem. The BIPM standard is ionometric using a graphite-walled cavity ionization chamber. The comparison result is 1.0024 (standard uncertainty 0.0029). (authors)

  14. Reformulation of a clinical-dose system for carbon-ion radiotherapy treatment planning at the National Institute of Radiological Sciences, Japan.

    Science.gov (United States)

    Inaniwa, Taku; Kanematsu, Nobuyuki; Matsufuji, Naruhiro; Kanai, Tatsuaki; Shirai, Toshiyuki; Noda, Koji; Tsuji, Hiroshi; Kamada, Tadashi; Tsujii, Hirohiko

    2015-04-21

    At the National Institute of Radiological Sciences (NIRS), more than 8,000 patients have been treated for various tumors with carbon-ion (C-ion) radiotherapy in the past 20 years based on a radiobiologically defined clinical-dose system. Through clinical experience, including extensive dose escalation studies, optimum dose-fractionation protocols have been established for respective tumors, which may be considered as the standards in C-ion radiotherapy. Although the therapeutic appropriateness of the clinical-dose system has been widely demonstrated by clinical results, the system incorporates several oversimplifications such as dose-independent relative biological effectiveness (RBE), empirical nuclear fragmentation model, and use of dose-averaged linear energy transfer to represent the spectrum of particles. We took the opportunity to update the clinical-dose system at the time we started clinical treatment with pencil beam scanning, a new beam delivery method, in 2011. The requirements for the updated system were to correct the oversimplifications made in the original system, while harmonizing with the original system to maintain the established dose-fractionation protocols. In the updated system, the radiation quality of the therapeutic C-ion beam was derived with Monte Carlo simulations, and its biological effectiveness was predicted with a theoretical model. We selected the most used C-ion beam with αr = 0.764 Gy(-1) and β = 0.0615 Gy(-2) as reference radiation for RBE. The C-equivalent biological dose distribution is designed to allow the prescribed survival of tumor cells of the human salivary gland (HSG) in entire spread-out Bragg peak (SOBP) region, with consideration to the dose dependence of the RBE. This C-equivalent biological dose distribution is scaled to a clinical dose distribution to harmonize with our clinical experiences with C-ion radiotherapy. Treatment plans were made with the original and the updated clinical-dose systems, and both

  15. SPECIAL CONSIDERATIONS REGARDING WARFARIN DOSE TITRATION IN PATIENTS WITH ATRIAL FIBRILLATION DEPENDING ON CLINICAL FACTORS

    OpenAIRE

    E. L. Artanova; E. V. Saleeva; I. M. Sokolov; Y. G. Shvarts

    2011-01-01

    Aim. To study the relations of clinical characteristics and individual warfarin dose titration in patients with atrial fibrillation. Material and methods. Period of warfarin dose titration was analyzed in 68 patients with atrial fibrillation due to ischemic heart disease. Adjusted warfarin dose in milligram, duration of dose titration in days and maximal international normalized ratio (INR) were taken into account. Sex, age, history of myocardial infarction and stroke, concomitant diseases, a...

  16. CDISC standard-based electronic archiving of clinical trials.

    Science.gov (United States)

    Kuchinke, Wolfgang; Aerts, J; Semler, S C; Ohmann, C

    2009-01-01

    Our objectives were to develop, based on the analysis of archived clinical trial documents and data and on the requirements of GCP-compliant electronic archiving, a concept for legally secure and technically feasible archiving of the entire clinical trial, including the essential documents of the trial master file and the study database. Based on own experiences with CDISC, existing implementations and future developments, CDISC standards were evaluated concerning requirements for archiving clinical studies. Trial master files of a small, medium and large clinical study were analyzed to collect specifications for electronic archiving of records. Two different ways of long-term storage exist for the clinical trial archive: document-oriented archival and data archiving of the study database. The trial master file has a highly complex structure; its different parts can vary greatly in size, depending of the working style of investigators, number of patients recruited, the number of adverse event reports and the number of queries. The CDISC standard ODM is especially suited for archiving clinical trials, because among other features it contains the entire clinical trial data and full audit trail information. On the other hand SDTM is a content standard suited for data warehouses. Two recent developments in CDISC will affect the archival of studies: the further development of ODM in the area of "eCRF submission" and the use of "Electronic Source Data". The complexity and size of the trial master file requires new solutions. Though ODM provides effective means to archive the study database, it shows still deficiencies, especially for the joint archiving of data and the complex documentation of the trial master file. A concept was developed in which the ODM standard is part of an integrated archiving of the trial data and documents. ODM archiving of the study database enables long-term storage which is GCP-compliant. Archiving of documents of the trial master file in PDF

  17. A method to adjust radiation dose-response relationships for clinical risk factors

    DEFF Research Database (Denmark)

    Appelt, Ane Lindegaard; Vogelius, Ivan R

    2012-01-01

    Several clinical risk factors for radiation induced toxicity have been identified in the literature. Here, we present a method to quantify the effect of clinical risk factors on radiation dose-response curves and apply the method to adjust the dose-response for radiation pneumonitis for patients...

  18. Single Dose Versus 3 Doses of Intramuscular Benzathine Penicillin for Early Syphilis in HIV: A Randomized Clinical Trial.

    Science.gov (United States)

    Andrade, Roberto; Rodriguez-Barradas, Maria C; Yasukawa, Kosuke; Villarreal, Erick; Ross, Michael; Serpa, Jose A

    2017-03-15

    Patients coinfected with syphilis and human immunodeficiency virus (HIV) may have a slower decrease in rapid plasma reagin (RPR) titers. Currently a single dose of 2.4 million units of intramuscular benzathine penicillin G (BPG) is recommended for the treatment of early syphilis. Some observational studies have suggested that this regimen may lead to high failure rates in coinfected patients. We conducted an open-label randomized clinical trial to compare the efficacy of single-dose and 3-dose regimens of BPG for the treatment of early syphilis in HIV-infected individuals. RPR titers were monitored every 3 months. Treatment success was defined as a decrease in RPR titers of ≥2 dilutions (4-fold) during a 12-month follow-up period. Sixty-four patients were included. In the intention-to-treat analysis, treatment success rates were 80% (28 of 35 subjects) and 93% (27 of 29 subjects) in the single-dose and 3-dose regimens, respectively (absolute difference, 13% [95% confidence interval {CI}, -5% to 30%; P = .17). In the per-protocol analysis, success rates were 93% (27 of 29) and 100% in the single-dose and 3-dose regimens, respectively (absolute difference, 7% [95% CI, -7% to 22%]; P = .49). CD4 T-cell count, RPR titer and syphilis stage did not affect treatment results. When compared with a single dose of BPG, a 3-dose regimen did not improve syphilis serological outcomes. Our results support the Centers for Disease Control and Prevention recommendation of a single dose of BPG in HIV-infected patients with early syphilis. NCT02611765.

  19. Standardizing Benchmark Dose Calculations to Improve Science-Based Decisions in Human Health Assessments

    Science.gov (United States)

    Wignall, Jessica A.; Shapiro, Andrew J.; Wright, Fred A.; Woodruff, Tracey J.; Chiu, Weihsueh A.; Guyton, Kathryn Z.

    2014-01-01

    Background: Benchmark dose (BMD) modeling computes the dose associated with a prespecified response level. While offering advantages over traditional points of departure (PODs), such as no-observed-adverse-effect-levels (NOAELs), BMD methods have lacked consistency and transparency in application, interpretation, and reporting in human health assessments of chemicals. Objectives: We aimed to apply a standardized process for conducting BMD modeling to reduce inconsistencies in model fitting and selection. Methods: We evaluated 880 dose–response data sets for 352 environmental chemicals with existing human health assessments. We calculated benchmark doses and their lower limits [10% extra risk, or change in the mean equal to 1 SD (BMD/L10/1SD)] for each chemical in a standardized way with prespecified criteria for model fit acceptance. We identified study design features associated with acceptable model fits. Results: We derived values for 255 (72%) of the chemicals. Batch-calculated BMD/L10/1SD values were significantly and highly correlated (R2 of 0.95 and 0.83, respectively, n = 42) with PODs previously used in human health assessments, with values similar to reported NOAELs. Specifically, the median ratio of BMDs10/1SD:NOAELs was 1.96, and the median ratio of BMDLs10/1SD:NOAELs was 0.89. We also observed a significant trend of increasing model viability with increasing number of dose groups. Conclusions: BMD/L10/1SD values can be calculated in a standardized way for use in health assessments on a large number of chemicals and critical effects. This facilitates the exploration of health effects across multiple studies of a given chemical or, when chemicals need to be compared, providing greater transparency and efficiency than current approaches. Citation: Wignall JA, Shapiro AJ, Wright FA, Woodruff TJ, Chiu WA, Guyton KZ, Rusyn I. 2014. Standardizing benchmark dose calculations to improve science-based decisions in human health assessments. Environ Health

  20. Effects of dose reduction on the detectability of standardized radiolucent lesions in digital panoramic radiography.

    Science.gov (United States)

    Dula, K; Sanderink, G; van der Stelt, P F; Mini, R; Buser, D

    1998-08-01

    Dose reduction in digital panoramic radiography was studied. Intentional underexposure was performed with the Orthophos DS while six different human mandibles were radiographed. Exposure settings were 69 kV/15 mA (standard), 64 kV/16 mA, and 60 kV/16 mA. Standardized spherical defects, each either 1 or 1.25 mm in diameter, were simulated in 288 of 432 images, and seven observers decided whether defects were present or not. Areas under the receiver operating characteristics curves were calculated. They showed no significant differences in the detectability of the 1-mm defect at 69, 64, or 60 kV. For the 1.25-mm defect, no difference was found between the 69 and 60 kV images, but a statistically significant different detectability was found for 64 kV images in comparison with both 69 and 60 kV images. A dose reduction of up to 43% was ascertained with a Pedo-RT-Humanoid phantom when panoramic radiography was performed at 60 kV/16 mA. The conclusion is that with the Orthophos DS, it seems possible to reduce the dose rate of x-rays without loss of diagnostic quality in the case of radiolucent changes.

  1. Supplementary comparison CCRI(I)-S2 of standards for absorbed dose to water in 60Co gamma radiation at radiation processing dose levels

    DEFF Research Database (Denmark)

    Burns, D. T.; Allisy-Roberts, P. J.; Desrosiers, M. F.

    2011-01-01

    Eight national standards for absorbed dose to water in 60Co gamma radiation at the dose levels used in radiation processing have been compared over the range from 1 kGy to 30 kGy using the alanine dosimeters of the NIST and the NPL as the transfer dosimeters. The comparison was organized by the B......Eight national standards for absorbed dose to water in 60Co gamma radiation at the dose levels used in radiation processing have been compared over the range from 1 kGy to 30 kGy using the alanine dosimeters of the NIST and the NPL as the transfer dosimeters. The comparison was organized...... by the Bureau International des Poids et Mesures, who also participated at the lowest dose level using their radiotherapy-level standard for the same quantity. The national standards are in general agreement within the standard uncertainties, which are in the range from 1 to 2 parts in 102. Evidence of a dose...

  2. Evaluation of reduced-dose CT for acute non-traumatic abdominal pain: evaluation of diagnostic accuracy in comparison to standard-dose CT.

    Science.gov (United States)

    Othman, Ahmed E; Bongers, Malte Niklas; Zinsser, Dominik; Schabel, Christoph; Wichmann, Julian L; Arshid, Rami; Notohamiprodjo, Mike; Nikolaou, Konstantin; Bamberg, Fabian

    2018-01-01

    Background Patients with acute non-traumatic abdominal pain often undergo abdominal computed tomography (CT). However, abdominal CT is associated with high radiation exposure. Purpose To evaluate diagnostic performance of a reduced-dose 100 kVp CT protocol with advanced modeled iterative reconstruction as compared to a linearly blended 120 kVp protocol for assessment of acute, non-traumatic abdominal pain. Material and Methods Two radiologists assessed 100 kVp and linearly blended 120 kVp series of 112 consecutive patients with acute non-traumatic pain (onset diagnostic confidence. Both 100 kVp and linearly blended 120 kVp series were quantitatively evaluated regarding radiation dose and image noise. Comparative statistics and diagnostic accuracy was calculated using receiver operating curve (ROC) statistics, with final clinical diagnosis/clinical follow-up as reference standard. Results Image quality was high for both series without detectable significant differences ( P = 0.157). Image noise and artifacts were rated low for both series but significantly higher for 100 kVp ( P ≤ 0.021). Diagnostic accuracy was high for both series (120 kVp: area under the curve [AUC] = 0.950, sensitivity = 0.958, specificity = 0.941; 100 kVp: AUC ≥ 0.910, sensitivity ≥ 0.937, specificity = 0.882; P ≥ 0.516) with almost perfect inter-rater agreement (Kappa = 0.939). Diagnostic confidence was high for both dose levels without significant differences (100 kVp 5, range 4-5; 120 kVp 5, range 3-5; P = 0.134). The 100 kVp series yielded 26.1% lower radiation dose compared with the 120 kVp series (5.72 ± 2.23 mSv versus 7.75 ± 3.02 mSv, P diagnostic accuracy for the assessment of acute non-traumatic abdominal pain.

  3. SPIRIT 2013 Statement: defining standard protocol items for clinical trials

    Directory of Open Access Journals (Sweden)

    An-Wen Chan

    Full Text Available The protocol of a clinical trial serves as the foundation for study planning, conduct, reporting, and appraisal. However, trial protocols and existing protocol guidelines vary greatly in content and quality. This article describes the systematic development and scope of SPIRIT (Standard Protocol Items: Recommendations for Interventional Trials 2013, a guideline for the minimum content of a clinical trial protocol. The 33-item SPIRIT checklist applies to protocols for all clinical trials and focuses on content rather than format. The checklist recommends a full description of what is planned; it does not prescribe how to design or conduct a trial. By providing guidance for key content, the SPIRIT recommendations aim to facilitate the drafting of high-quality protocols. Adherence to SPIRIT would also enhance the transparency and completeness of trial protocols for the benefit of investigators, trial participants, patients, sponsors, funders, research ethics committees or institutional review boards, peer reviewers, journals, trial registries, policymakers, regulators, and other key stakeholders.

  4. Assessment of organ doses by standard X-ray procedures in the GDR

    International Nuclear Information System (INIS)

    Tautz, M.; Brandt, G.A.

    1986-01-01

    A modern method has been described to assess the radiation burden by X-ray procedures with consideration of the standards of our Society for Medical Radiology in the GDR. The underlying methodology is a Monte Carlo computer technique, which simulates stochastically the energy deposition of X-ray photons in a mathematically described heterogeneous anthropomorphic phantom by Rosenstein (US Department of Health, Education and Welfare). To apply the procedure specific values for the following parameters must be determined for each dose estimation: projection and view, X-ray field size and location entrance exposure at skin surface, beam quality, source-to-image receptor distance. The base data are obtained in terms of tissue-air ratio. Organ doses were calculated for chest, urography, skull, cervical spine, thoracic spine, lumbar spine, pelvis and lymphography. Concluding possibilities have been discussed for reduction of radiation burden. 9 refs., 6 figs., 9 tabs. (author)

  5. A logistic dose-ranging method for phase I clinical investigations trials.

    Science.gov (United States)

    Murphy, J R; Hall, D L

    1997-11-01

    This paper describes an alternative to the continual reassessment method (CRM) for phase I trials. The logistic dose ranging strategy (LDRS) uses logistic regression and a dose allocation scheme similar to the CRM. It can easily be implemented from any logistic regression program. The LDRS can be a stand alone dose allocation scheme or it can be incorporated into standard three on a dose strategies to indicate when escalation can proceed more rapidly. Finally, the effect of covariates such as age or comorbid conditions on the toxicity expected for the dose selected for a phase II trial can be examined.

  6. Development of standardized methods to verify absorbed dose of irradiated fresh and dried fruits, tree nuts in trade

    International Nuclear Information System (INIS)

    Siddiqui, A.K.; Amin, M.R.; Chowdhury, N.A.; Begum, F.; Mollah, A.S.; Mollah, R.A.; Chowdhury, A.H.

    2001-01-01

    Investigations were carried out on standardization of desired process control parameters such as dose distribution in trade containers, container standardization and development of 'label' dosimeters. A prototype 'label' dose indicators Sterins for threshold doses of 125 Gy and 300 Gy was studied. Dose distribution was studied using fresh fruits and tree nuts in trade and standardized containers with varying product densities. The distribution of absorbed doses was measured by Fricke, Gammachrome YR, clear Polymethylmethacrylate (PMMA), EthanolChlorobenzene (ECB) and Sterin 300. These values are given as Dmax/Dmin ratios in relation to product bulk densities. It was observed that bulk densities varied greatly among different products depending on the types of fruits, containers and pattern of loading which also affected dose distribution. Dmax/Dmin obtained by proper dose mapping could be kept low by arranging proper irradiation conditions which ensured uniform dose distribution. Prototype 'label' dose indicators like Sterins and clear PMMA were used for dose mapping along with the standard primary and secondary dosimeters. Sterins and clear PMMA were also studied for their dosimetric properties, particularly for use in label dosimetry. Sterins 125 and 300 evaluated visually showed their integrity at their threshold doses. The word NOT on Sterin 125 eclipsed after 115 Gy and on Sterin 300 after 270 Gy dose. Clear PMMA samples of 410 mm thickness irradiated at 200-1000 Gy showed linear response and had postirradiation stability for over a month storage at normal temperatures (21-35 deg. C) and humidities. These could be investigated further for developing as 'label' dosimeters in insect control quarantine treatment. Other low dose indicators studied such as coloured perspex, dye solutions were not found useful at quarantine dose levels. Further investigations are required for developing a 'label' dosimeter for commercial use. (author)

  7. SPECIAL CONSIDERATIONS REGARDING WARFARIN DOSE TITRATION IN PATIENTS WITH ATRIAL FIBRILLATION DEPENDING ON CLINICAL FACTORS

    Directory of Open Access Journals (Sweden)

    E. L. Artanova

    2011-01-01

    Full Text Available Aim. To study the relations of clinical characteristics and individual warfarin dose titration in patients with atrial fibrillation. Material and methods. Period of warfarin dose titration was analyzed in 68 patients with atrial fibrillation due to ischemic heart disease. Adjusted warfarin dose in milligram, duration of dose titration in days and maximal international normalized ratio (INR were taken into account. Sex, age, history of myocardial infarction and stroke, concomitant diseases, amiodarone therapy were considered among clinical characteristics. Results. Adjusted warfarin dose was significantly higher in obesity , and it was lower in case of experienced myocardial infarction. The INR highest levels and maximal amplitudes of its fluctuations were observed in patients with thyroid gland nodes and smokers. Period of warfarin dose titration was longer in patients treated with amiodarone. Conclusion. Warfarin dose titration in patients with atrial fibrillation depends on the presence of myocardial infarction, obesity , thyroid nodular changes, smoking and amiodarone treatment.

  8. A standardized clinical evaluation of phenotypic diversity in diabetic polyneuropathy.

    Science.gov (United States)

    Scholz, Joachim; Rathmell, James P; David, William S; Chad, David A; Broderick, Alithia C; Perros, Stephen G; Shin, Naomi S; Wells, Jenna L; Davis, John B; DiMaggio, Charles J; Wang, Shuang; Tate, Simon N

    2016-10-01

    Diabetic polyneuropathy (DPN) is a major cause of neuropathic pain and a frequent target condition in analgesic treatment trials. Differences in the clinical symptoms and signs associated with DPN suggest distinct pathophysiological mechanisms underlying nerve damage and dysfunction that are likely to have therapeutic relevance. The aim of this study was to develop a tool for the bedside assessment of painful neuropathies such as DPN that captures the diversity of phenotypes. Sixty-one patients with type 2 diabetes and painful neuropathy, 19 patients with painless DPN, 25 patients with type 2 diabetes but no clinical evidence of neuropathy, and 20 healthy control subjects completed a structured interview (47 items) and a standardized physical examination (39 items). After analyzing critical features of pain and painless symptoms and examining the outcome of physical tests of sensory function, we determined principal components of the phenotypic variance among patients. Increased sensitivity to mechanical or thermal stimuli and, to a lesser extent, the sensory quality of pain or paresthesia were the most discriminating elements of DPN phenotypes. Correlation patterns of symptoms and signs indicated the involvement of functionally distinct nerve fiber populations. We combined interview questions and physical tests identifying these differences in a shortened assessment protocol that we named Standardized Evaluation of Pain and Somatosensory Function (StEPS). The protocol StEPS generates a phenotypic profile of patients with neuropathy. Separate intensity ratings for spontaneous painful symptoms and pain evoked by standard stimuli support a detailed documentation of neuropathic pain and its response to analgesic treatment.

  9. Individualized versus standard FSH dosing in women starting IVF/ICSI: an RCT. Part 2: The predicted hyper responder.

    Science.gov (United States)

    Oudshoorn, Simone C; van Tilborg, Theodora C; Eijkemans, Marinus J C; Oosterhuis, G Jur E; Friederich, Jaap; van Hooff, Marcel H A; van Santbrink, Evert J P; Brinkhuis, Egbert A; Smeenk, Jesper M J; Kwee, Janet; de Koning, Corry H; Groen, Henk; Lambalk, Cornelis B; Mol, Ben Willem J; Broekmans, Frank J M; Torrance, Helen L

    2017-12-01

    cumulative live birth rate was 66.3% (169/255) in the reduced versus 69.5% (185/266) in the standard group (relative risk (RR) 0.95 [95%CI, 0.85-1.07], P = 0.423). The occurrence of any grade of OHSS was lower after a lower FSH dose (5.2% versus 11.8%, RR 0.44 [95%CI, 0.28-0.71], P = 0.001), but the occurrence of severe OHSS did not differ (1.3% versus 1.1%, RR 1.25 [95%CI, 0.38-4.07], P = 0.728). As dose reduction was not less expensive (€4.622 versus €4.714, delta costs/woman €92 [95%CI, -479-325]), there was no dominant strategy in the economic analysis. Despite our training programme, the AFC might have suffered from inter-observer variation. Although strict cancellation criteria were provided, selective cancelling in the reduced dose group (for poor response in particular) cannot be excluded as observers were not blinded for the FSH dose and small dose adjustments were allowed in subsequent cycles. However, as first cycle live birth rates did not differ from the cumulative results, the open design probably did not mask a potential benefit for the reduced dosing group. As this RCT was embedded in a larger cohort study, the power in this study was unavoidably lower than it should be. Participants had a relatively low BMI from an international perspective, which may limit generalization of the findings. In women with a predicted hyper response scheduled for IVF/ICSI, a reduced FSH dose does not affect live birth rates. A lower FSH dose did reduce the incidence of mild and moderate OHSS, but had no impact on severe OHSS. Future research into ORT-based dosing in women with a predicted hyper response should compare various safety management strategies and should be powered on a clinically relevant safety outcome while assessing non-inferiority towards live birth rates. This trial was funded by The Netherlands Organization for Health Research and Development (ZonMW, Project Number 171102020). SCO, TCvT and HLT received an unrestricted research grant from Merck Serono

  10. Offsite dose calculation manual guidance: Standard radiological effluent controls for pressurized water reactors

    International Nuclear Information System (INIS)

    Meinke, W.W.; Essig, T.H.

    1991-04-01

    This report contains guidance which may be voluntarily used by licensees who choose to implement the provision of Generic Letter 89-01, which allows Radiological Effect Technical Specifications (RETS) to be removed from the main body of the Technical Specifications and placed in the Offsite Dose Calculation Manual (ODCM). Guidance is provided for Standard Effluent Controls definitions, Controls for effluent monitoring instrumentation, Controls for effluent releases, Controls for radiological environmental monitoring, and the basis for Controls. Guidance on the formulation of RETS has been available in draft from (NUREG-0471 and -0473) for a number of years; the current effort simply recasts those RETS into Standard Radiological Effluent Controls for application to the ODCM. Also included for completeness are: (1) radiological environmental monitoring program guidance previously which had been available as a Branch Technical Position (Rev. 1, November 1979); (2) existing ODCM guidance; and (3) a reproduction of generic Letter 89-01

  11. Comparison of Low- and Standard-Dose CT for the Diagnosis of Acute Appendicitis: A Meta-Analysis.

    Science.gov (United States)

    Yun, Seong Jong; Ryu, Chang-Woo; Choi, Na Young; Kim, Hyun Cheol; Oh, Ji Young; Yang, Dal Mo

    2017-06-01

    A meta-analysis was performed to compare low-dose CT and standard-dose CT in the diagnosis of acute appendicitis with an emphasis on diagnostic value. A systematic literature search for articles published through June 2016 was performed to identify studies that compared low-dose CT with standard-dose CT for the evaluation of patients suspected of having acute appendicitis. Summary estimates of sensitivity and specificity with 95% CIs were calculated using a bivariate random-effects model. Meta-regression was used to perform statistical comparisons of low-dose CT and standard-dose CT. Of 154 studies, nine studies investigating a total of 2957 patients were included in this meta-analysis. The pooled sensitivity and specificity of low-dose CT were 96.25% (95% CI, 91.88-98.31%) and 93.22% (95% CI, 88.75-96.00%), respectively. The pooled sensitivity and specificity of standard-dose CT were 96.40% (95% CI, 93.55-98.02%) and 92.17% (95% CI, 88.24-94.86%), respectively. In a joint model estimation of meta-regression, lowand standard-dose CT did not show a statistically significant difference (p = 0.71). Both lowand standard-dose CT seem to be characterized by high positive and negative predictive values across a broad spectrum of pretest probabilities for acute appendicitis. Low-dose CT is highly effective for the diagnosis of suspected appendicitis and can be considered a valid alternative first-line imaging test that reduces the potential risk of exposure to ionizing radiation.

  12. Virtual glaucoma clinics: patient acceptance and quality of patient education compared to standard clinics.

    Science.gov (United States)

    Court, Jennifer H; Austin, Michael W

    2015-01-01

    Virtual glaucoma clinics allow rapid, reliable patient assessment but the service should be acceptable to patients and concordance with treatment needs to be maintained with adequate patient education. This study compares experiences and understanding of patients reviewed via the virtual clinic versus the standard clinic by way of an extended patient satisfaction questionnaire (PSQ). One hundred PSQs were given to consecutive patients attending glaucoma clinics in October 2013. All 135 patients reviewed via the virtual clinic from April 2013 until August 2013 were sent postal PSQs in September 2013. Data were obtained for demographics, understanding of glaucoma, their condition, satisfaction with their experience, and quality of information. Responses were analyzed in conjunction with the clinical records. Eighty-five percent of clinic patients and 63% of virtual clinic patients responded to the PSQ. The mean satisfaction score was over 4.3/5 in all areas surveyed. Virtual clinic patients' understanding of their condition was very good, with 95% correctly identifying their diagnosis as glaucoma, 83% as ocular hypertension and 78% as suspects. There was no evidence to support inferior knowledge or self-perceived understanding compared to standard clinic patients. Follow-up patients knew more about glaucoma than new patients. Over 95% of patients found our information leaflet useful. Forty percent of patients sought additional information but less than 20% used the internet for this. A substantial proportion of glaucoma pathway patients may be seen by non-medical staff supervised by glaucoma specialists via virtual clinics. Patients are accepting of this format, reporting high levels of satisfaction and non-inferior knowledge to those seen in standard clinics.

  13. Virtual glaucoma clinics: patient acceptance and quality of patient education compared to standard clinics

    Directory of Open Access Journals (Sweden)

    Court JH

    2015-04-01

    Full Text Available Jennifer H Court,1 Michael W Austin1,21Department of Ophthalmology, Singleton Hospital, Swansea, Wales, UK; 2Department of Ophthalmology, Neath Port Talbot Hospital, Swansea, Wales, UKPurpose: Virtual glaucoma clinics allow rapid, reliable patient assessment but the service should be acceptable to patients and concordance with treatment needs to be maintained with adequate patient education. This study compares experiences and understanding of patients reviewed via the virtual clinic versus the standard clinic by way of an extended patient satisfaction questionnaire (PSQ.Patients and methods: One hundred PSQs were given to consecutive patients attending glaucoma clinics in October 2013. All 135 patients reviewed via the virtual clinic from April 2013 until August 2013 were sent postal PSQs in September 2013. Data were obtained for demographics, understanding of glaucoma, their condition, satisfaction with their experience, and quality of information. Responses were analyzed in conjunction with the clinical records.Results: Eighty-five percent of clinic patients and 63% of virtual clinic patients responded to the PSQ. The mean satisfaction score was over 4.3/5 in all areas surveyed. Virtual clinic patients’ understanding of their condition was very good, with 95% correctly identifying their diagnosis as glaucoma, 83% as ocular hypertension and 78% as suspects. There was no evidence to support inferior knowledge or self-perceived understanding compared to standard clinic patients. Follow-up patients knew more about glaucoma than new patients. Over 95% of patients found our information leaflet useful. Forty percent of patients sought additional information but less than 20% used the internet for this.Conclusion: A substantial proportion of glaucoma pathway patients may be seen by non-medical staff supervised by glaucoma specialists via virtual clinics. Patients are accepting of this format, reporting high levels of satisfaction and non

  14. Reduced Radiation Dose with Model-based Iterative Reconstruction versus Standard Dose with Adaptive Statistical Iterative Reconstruction in Abdominal CT for Diagnosis of Acute Renal Colic.

    Science.gov (United States)

    Fontarensky, Mikael; Alfidja, Agaïcha; Perignon, Renan; Schoenig, Arnaud; Perrier, Christophe; Mulliez, Aurélien; Guy, Laurent; Boyer, Louis

    2015-07-01

    To evaluate the accuracy of reduced-dose abdominal computed tomographic (CT) imaging by using a new generation model-based iterative reconstruction (MBIR) to diagnose acute renal colic compared with a standard-dose abdominal CT with 50% adaptive statistical iterative reconstruction (ASIR). This institutional review board-approved prospective study included 118 patients with symptoms of acute renal colic who underwent the following two successive CT examinations: standard-dose ASIR 50% and reduced-dose MBIR. Two radiologists independently reviewed both CT examinations for presence or absence of renal calculi, differential diagnoses, and associated abnormalities. The imaging findings, radiation dose estimates, and image quality of the two CT reconstruction methods were compared. Concordance was evaluated by κ coefficient, and descriptive statistics and t test were used for statistical analysis. Intraobserver correlation was 100% for the diagnosis of renal calculi (κ = 1). Renal calculus (τ = 98.7%; κ = 0.97) and obstructive upper urinary tract disease (τ = 98.16%; κ = 0.95) were detected, and differential or alternative diagnosis was performed (τ = 98.87% κ = 0.95). MBIR allowed a dose reduction of 84% versus standard-dose ASIR 50% (mean volume CT dose index, 1.7 mGy ± 0.8 [standard deviation] vs 10.9 mGy ± 4.6; mean size-specific dose estimate, 2.2 mGy ± 0.7 vs 13.7 mGy ± 3.9; P < .001) without a conspicuous deterioration in image quality (reduced-dose MBIR vs ASIR 50% mean scores, 3.83 ± 0.49 vs 3.92 ± 0.27, respectively; P = .32) or increase in noise (reduced-dose MBIR vs ASIR 50% mean, respectively, 18.36 HU ± 2.53 vs 17.40 HU ± 3.42). Its main drawback remains the long time required for reconstruction (mean, 40 minutes). A reduced-dose protocol with MBIR allowed a dose reduction of 84% without increasing noise and without an conspicuous deterioration in image quality in patients suspected of having renal colic.

  15. Comparison of doses delivered in clinical trials of neutron capture therapy in the USA

    International Nuclear Information System (INIS)

    Albritton, J.R.; Binns, P.J.; Riley, K.J.; Coderre, J.A.; Harling, O.K.; Kiger, W.S. III

    2006-01-01

    A combined 81 brain tumor patients have been treated in dose escalation trials of Neutron Capture Therapy (NCT) at Harvard-MIT and Brookhaven National Laboratory (BNL). Pooling the clinical outcomes from these trials will permit evaluation with more statistical rigor. However, differences in physical and computational dosimetry between the institutions make direct comparison of the clinical dosimetry difficult. This paper describes work performed to normalize the BNL clinical dosimetry to that of Harvard-MIT for combined dose response analysis. This normalization involved analysis of MIT measurements and calculations using the BNL treatment planning system (TPS), BNCT - Rtpe, for two different phantoms. The BNL TPS was calibrated to dose measurements made by MIT at the BMRR in the BNL calibration phantom, a Lucite cube, and then validated by MIT dose measurements at the BMMR in an ellipsoidal water phantom. Treatment plans for all BNL patients were recomputed using the newly determined TPS calibration, yielding reductions in reported mean brain doses of 19% on average in the initial 15 patients and 31% in the latter 38 patients. These reductions in reported doses have clinically significant implications for those relying on reported BNL doses as a basis for initial dose selection in clinical studies. (author)

  16. Standard Procedure for Dose Assessment using the film holder NRPB/AERE and the film AGFA Monitoring 2/10

    International Nuclear Information System (INIS)

    Guillen, J.A.

    1998-07-01

    This paper describes the calculation method to assess dose and energy using the film holder from NRPB/AERE and the film Agfa Monitoring 2/10. Also includes all the steps since preparing the standard curve, fitting of calibration curve, dose assesment, description of filtration of the film holder and the form of the calibration curve

  17. An adaptive design for phase II non-oncology dose selection clinical trials.

    Science.gov (United States)

    Su, Zheng

    2010-01-01

    A non-oncology dose selection phase II trial tests multiple active doses in a controlled fashion, and it not only needs to determine whether the treatment is effective but also to select the 'lowest efficacious' dose if the treatment is indeed efficacious. Few approaches exist in the literature for designing phase II non-oncology dose selection trials, and the standard design with a fixed sample size has been widely used. The objective of this study was to develop a more efficient design for phase II dose selection trials that terminates the trial early for futility and adjusts the sample size and number of doses at interim analyses when appropriate. One-sided statistical tests and confidence intervals were used to develop an adaptive design for non-oncology phase II dose selection trials. With several interim analyses built in, the adaptive design uses accumulated data to determine, at each interim analysis, whether the highest dose is efficacious and whether the low doses are as efficacious as the highest dose. Once a confident answer to either or both of these questions can be obtained, the trial may either be terminated early or some of the lower doses may be dropped to prevent assigning more patients to inferior doses and thus reduce the total sample size needed. Theoretical analyses and simulation studies show that the proposed adaptive design significantly outperforms the standard design with a fixed sample size. The proposed adaptive design should be preferred over the standard design especially in cases where enrolment is slow and efficacy can be measured after a relatively short period of time.

  18. Intravenous iron isomaltoside 1000 administered by high single-dose infusions or standard medical care for the treatment of fatigue in women after postpartum haemorrhage

    DEFF Research Database (Denmark)

    Holm, Charlotte; Thomsen, Lars Lykke; Norgaard, Astrid

    2015-01-01

    randomised controlled studies have compared the clinical efficacy and safety of standard medical care with intravenous administration of iron supplementation after postpartum haemorrhage.The primary objective of this study is to compare the efficacy of an intravenous high single-dose of iron isomaltoside...... medical care. Healthy parturients with a singleton pregnancy will be included within 48 hours after delivery.Participants will complete structured questionnaires that focus on several dimensions of fatigue and mental health (Multidimensional Fatigue Inventory, Edinburgh Postnatal Depression Scale...... Inventory. The primary objective will be considered to have been met if an intravenous high single dose of iron isomaltoside 1000 is shown to be superior to standard medical care in women after postpartum haemorrhage regarding physical fatigue.For claiming superiority, we set the minimal clinically relevant...

  19. Ultralow-Dose Abdominal Computed Tomography: Comparison of 2 Iterative Reconstruction Techniques in a Prospective Clinical Study.

    Science.gov (United States)

    Khawaja, Ranish Deedar Ali; Singh, Sarabjeet; Blake, Michael; Harisinghani, Mukesh; Choy, Gary; Karaosmanoglu, Ali; Karosmanoglu, Ali; Padole, Atul; Pourjabbar, Saravenaz; Do, Synho; Kalra, Mannudeep K

    2015-01-01

    To assess lesion detection and image quality of ultralow-dose (ULD) abdominal computed tomography (CT) reconstructed with filtered back projection (FBP) and 2 iterative reconstruction techniques: hybrid-based iDose, and image-based SafeCT. In this institutional review board-approved ongoing prospective clinical study, 41 adult patients provided written informed consent for an additional ULD abdominal CT examination immediately after standard dose (SD) CT exam on a 256-slice multidetector computed tomography (iCT, Philips-Healthcare). The SD examination (size-specific dose estimate, 10 ± 3 mGy) was performed at 120 kV with automatic exposure control, and reconstructed with FBP. The ULD examination (1.5 ± 0.4 mGy) was performed at 120 kV and fixed tube current of 17 to 20 mAs/slice to achieve ULD radiation dose, with the rest of the scan parameters same as SD examination. The ULD data were reconstructed with (a) FBP, (b) iDose, and (c) SafeCT. Lesions were detected on ULD FBP series and compared to SD FBP "reference-standard" series. True lesions, pseudolesions, and missed lesions were recorded. Four abdominal radiologists independently blindly performed subjective image quality. Objective image quality included image noise calculation and noise spectral density plots. All true lesions (n, 52: liver metastases, renal cysts, diverticulosis) in SD FBP images were detected in ULD images. Although there were no missed or pseudolesions on ULD iDose and ULD SafeCT images, appearance of small low-contrast hepatic lesions was suboptimal. The ULD FBP images were unacceptable across all patients for both lesion detection and image quality. In patients with a body mass index (BMI) of 25 kg/m or less, ULD iDose and ULD SafeCT images were acceptable for image quality that was close to SD FBP for both normal and abnormal abdominal and pelvic structures. With increasing BMI, the image quality of ULD images was deemed unacceptable due to photo starvation. Evaluation of kidney

  20. Clinical Utility and Safety of a Model-Based Patient-Tailored Dose of Vancomycin in Neonates.

    Science.gov (United States)

    Leroux, Stéphanie; Jacqz-Aigrain, Evelyne; Biran, Valérie; Lopez, Emmanuel; Madeleneau, Doriane; Wallon, Camille; Zana-Taïeb, Elodie; Virlouvet, Anne-Laure; Rioualen, Stéphane; Zhao, Wei

    2016-04-01

    Pharmacokinetic modeling has often been applied to evaluate vancomycin pharmacokinetics in neonates. However, clinical application of the model-based personalized vancomycin therapy is still limited. The objective of the present study was to evaluate the clinical utility and safety of a model-based patient-tailored dose of vancomycin in neonates. A model-based vancomycin dosing calculator, developed from a population pharmacokinetic study, has been integrated into the routine clinical care in 3 neonatal intensive care units (Robert Debré, Cochin Port Royal, and Clocheville hospitals) between 2012 and 2014. The target attainment rate, defined as the percentage of patients with a first therapeutic drug monitoring serum vancomycin concentration achieving the target window of 15 to 25 mg/liter, was selected as an endpoint for evaluating the clinical utility. The safety evaluation was focused on nephrotoxicity. The clinical application of the model-based patient-tailored dose of vancomycin has been demonstrated in 190 neonates. The mean (standard deviation) gestational and postnatal ages of the study population were 31.1 (4.9) weeks and 16.7 (21.7) days, respectively. The target attainment rate increased from 41% to 72% without any case of vancomycin-related nephrotoxicity. This proof-of-concept study provides evidence for integrating model-based antimicrobial therapy in neonatal routine care. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  1. Immunogenicity and safety of high-dose trivalent inactivated influenza vaccine compared to standard-dose vaccine in children and young adults with cancer or HIV infection.

    Science.gov (United States)

    Hakim, Hana; Allison, Kim J; Van de Velde, Lee-Ann; Tang, Li; Sun, Yilun; Flynn, Patricia M; McCullers, Jonathan A

    2016-06-08

    Approaches to improve the immune response of immunocompromised patients to influenza vaccination are needed. Children and young adults (3-21 years) with cancer or HIV infection were randomized to receive 2 doses of high-dose (HD) trivalent influenza vaccine (TIV) or of standard-dose (SD) TIV. Hemagglutination inhibition (HAI) antibody titers were measured against H1, H3, and B antigens after each dose and 9 months later. Seroconversion was defined as ≥4-fold rise in HAI titer comparing pre- and post-vaccine sera. Seroprotection was defined as a post-vaccine HAI titer ≥1:40. Reactogenicity events (RE) were solicited using a structured questionnaire 7 and 14 days after each dose of vaccine, and adverse events by medical record review for 21 days after each dose of vaccine. Eighty-five participants were enrolled in the study; 27 with leukemia, 17 with solid tumor (ST), and 41 with HIV. Recipients of HD TIV had significantly greater fold increase in HAI titers to B antigen in leukemia group and to H1 antigen in ST group compared to SD TIV recipients. This increase was not documented in HIV group. There were no differences in seroconversion or seroprotection between HD TIV and SD TIV in all groups. There was no difference in the percentage of solicited RE in recipients of HD TIV (54% after dose 1 and 38% after dose 2) compared to SD TIV (40% after dose 1 and 20% after dose 2, p=0.27 and 0.09 after dose 1 and 2, respectively). HD TIV was more immunogenic than SD TIV in children and young adults with leukemia or ST, but not with HIV. HD TIV was safe and well-tolerated in children and young adults with leukemia, ST, or HIV. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Evaluation of Wall Correction Factor of INER's Air-Kerma Primary Standard Chamber and Dose Variation by Source Displacement for HDR 192Ir Brachytherapy

    Directory of Open Access Journals (Sweden)

    J. H. Lee

    2013-01-01

    Full Text Available The aim of the present study was to estimate the wall effect of the self-made spherical graphite-walled cavity chamber with the Monte Carlo method for establishing the air-kerma primary standard of high-dose-rate (HDR 192Ir brachytherapy sources at the Institute of Nuclear Energy Research (INER, Taiwan. The Monte Carlo method established in this paper was also employed to respectively simulate wall correction factors of the 192Ir air-kerma standard chambers used at the National Institute of Standards and Technology (NIST, USA and the National Physical Laboratory (NPL, UK for comparisons and verification. The chamber wall correction calculation results will be incorporated into INER's HDR 192Ir primary standard in the future. For the brachytherapy treatment in the esophagus or in the bronchi, the position of the isotope may have displacement in the cavity. Thus the delivered dose would differ from the prescribed dose in the treatment plan. We also tried assessing dose distribution due to the position displacement of HDR 192Ir brachytherapy source in a phantom with a central cavity by the Monte Carlo method. The calculated results could offer a clinical reference for the brachytherapy within the human organs with cavity.

  3. Extracting and standardizing medication information in clinical text - the MedEx-UIMA system.

    Science.gov (United States)

    Jiang, Min; Wu, Yonghui; Shah, Anushi; Priyanka, Priyanka; Denny, Joshua C; Xu, Hua

    2014-01-01

    Extraction of medication information embedded in clinical text is important for research using electronic health records (EHRs). However, most of current medication information extraction systems identify drug and signature entities without mapping them to standard representation. In this study, we introduced the open source Java implementation of MedEx, an existing high-performance medication information extraction system, based on the Unstructured Information Management Architecture (UIMA) framework. In addition, we developed new encoding modules in the MedEx-UIMA system, which mapped an extracted drug name/dose/form to both generalized and specific RxNorm concepts and translated drug frequency information to ISO standard. We processed 826 documents by both systems and verified that MedEx-UIMA and MedEx (the Python version) performed similarly by comparing both results. Using two manually annotated test sets that contained 300 drug entries from medication list and 300 drug entries from narrative reports, the MedEx-UIMA system achieved F-measures of 98.5% and 97.5% respectively for encoding drug names to corresponding RxNorm generic drug ingredients, and F-measures of 85.4% and 88.1% respectively for mapping drug names/dose/form to the most specific RxNorm concepts. It also achieved an F-measure of 90.4% for normalizing frequency information to ISO standard. The open source MedEx-UIMA system is freely available online at http://code.google.com/p/medex-uima/.

  4. Maximal safe dose therapy of I-131 after failure of standard fixed dose therapy in patients with differentiated thyroid carcinoma

    International Nuclear Information System (INIS)

    Lee, Jong Jin; Seok, Ju Won; Uh, Jae Sun

    2005-01-01

    In patients with recurrent or metastatic differentiated thyroid carcinoma, residual disease despite repetitive fixed dose I-131 therapy presents an awkward situation in terms of treatment decision making. Maximal safe dose (MSD) administration base on bone marrow radiation allows the delivery of a large amount I-131 to thyroid cancer tissue within the safety margin. We investigated the efficacy of MSD in differentiated thyroid cancers, which had persisted after conventional fixed dose therapy. Forty-six patients with differentiated thyroid carcinoma who had non-responsible residual disease despite repetitive fixed dose I-131 therapy were enrolled in this study. The postoperative pathology consisted of 43 papillary carcinomas and 3 follicular carcinomas. MSD was calculated according the Memorial Sloan Kettering Cancer Center protocol using blood samples. MSDs were administered at intervals of at least 6 months. Treatment responses were evaluated using I-131 whole body scan (WBS) and serum thyroglobulin measurements. Mean calculated MSD was 12.5±2.1 GBq. Of the 46 patients, 6 (13.0%) showed complete remission, 15 (32.6%) partial response, 19 (41.3%) stable disease, and 6 (13.0%) disease progression. Thus, about a half of the patients showed complete or partial remission, and of these patients, 14 (67%) showed response after a single MSD administration and 6 (29%) showed response after the second dose of MSD administrations. Twenty-nine patients (63%) experienced transient cytopenia after therapy, and recovered spontaneously with the exception of one. MSD administration is an effective method even in the patients who failed to be treated by conventional fixed dose therapy. MSD therapy of I-131 can be considered in the patients who failed by fixed dose therapy

  5. Applicability Evaluation of Job Standards for Diabetes Nutritional Management by Clinical Dietitian

    OpenAIRE

    Baek, Young Jin; Oh, Na Gyeong; Sohn, Cheong-Min; Woo, Mi-Hye; Lee, Seung Min; Ju, Dal Lae; Seo, Jung-Sook

    2017-01-01

    This study was conducted to evaluate applicability of job standards for diabetes nutrition management by hospital clinical dietitians. In order to promote the clinical nutrition services, it is necessary to present job standards of clinical dietitian and to actively apply these standardized tasks to the medical institution sites. The job standard of clinical dietitians for diabetic nutrition management was distributed to hospitals over 300 beds. Questionnaire was collected from 96 clinical di...

  6. Pharmacogenetic versus clinical dosing of warfarin in individuals of Chinese and African-American ancestry: assessment using data simulation.

    Science.gov (United States)

    Syn, Nicholas L X; Lee, Soo-Chin; Brunham, Liam R; Goh, Boon-Cher

    2015-10-01

    Clinical trials of genotype-guided dosing of warfarin have yielded mixed results, which may in part reflect ethnic differences among study participants. However, no previous study has compared genotype-guided versus clinically guided or standard-of-care dosing in a Chinese population, whereas those involving African-Americans were underpowered to detect significant differences. We present a preclinical strategy that integrates pharmacogenetics (PG) and pharmacometrics to predict the outcome or guide the design of dosing strategies for drugs that show large interindividual variability. We use the example of warfarin and focus on two underrepresented groups in warfarin research. We identified the parameters required to simulate a patient population and the outcome of dosing strategies. PG and pharmacogenetic plus loading (PG+L) algorithms that take into account a patient's VKORC1 and CYP2C9 genotype status were considered and compared against a clinical (CA) algorithm for a simulated Chinese population using a predictive Monte Carlo and pharmacokinetic-pharmacodynamic framework. We also examined a simulated population of African-American ancestry to assess the robustness of the model in relation to real-world clinical trial data. The simulations replicated similar trends observed with clinical data in African-Americans. They further predict that the PG+L regimen is superior to both the CA and the PG regimen in maximizing percentage time in therapeutic range in a Chinese cohort, whereas the CA regimen poses the highest risk of overanticoagulation during warfarin initiation. The findings supplement the literature with an unbiased comparison of warfarin dosing algorithms and highlights interethnic differences in anticoagulation control.

  7. Standard and reduced radiation dose liver CT images: adaptive statistical iterative reconstruction versus model-based iterative reconstruction-comparison of findings and image quality.

    Science.gov (United States)

    Shuman, William P; Chan, Keith T; Busey, Janet M; Mitsumori, Lee M; Choi, Eunice; Koprowicz, Kent M; Kanal, Kalpana M

    2014-12-01

    To investigate whether reduced radiation dose liver computed tomography (CT) images reconstructed with model-based iterative reconstruction ( MBIR model-based iterative reconstruction ) might compromise depiction of clinically relevant findings or might have decreased image quality when compared with clinical standard radiation dose CT images reconstructed with adaptive statistical iterative reconstruction ( ASIR adaptive statistical iterative reconstruction ). With institutional review board approval, informed consent, and HIPAA compliance, 50 patients (39 men, 11 women) were prospectively included who underwent liver CT. After a portal venous pass with ASIR adaptive statistical iterative reconstruction images, a 60% reduced radiation dose pass was added with MBIR model-based iterative reconstruction images. One reviewer scored ASIR adaptive statistical iterative reconstruction image quality and marked findings. Two additional independent reviewers noted whether marked findings were present on MBIR model-based iterative reconstruction images and assigned scores for relative conspicuity, spatial resolution, image noise, and image quality. Liver and aorta Hounsfield units and image noise were measured. Volume CT dose index and size-specific dose estimate ( SSDE size-specific dose estimate ) were recorded. Qualitative reviewer scores were summarized. Formal statistical inference for signal-to-noise ratio ( SNR signal-to-noise ratio ), contrast-to-noise ratio ( CNR contrast-to-noise ratio ), volume CT dose index, and SSDE size-specific dose estimate was made (paired t tests), with Bonferroni adjustment. Two independent reviewers identified all 136 ASIR adaptive statistical iterative reconstruction image findings (n = 272) on MBIR model-based iterative reconstruction images, scoring them as equal or better for conspicuity, spatial resolution, and image noise in 94.1% (256 of 272), 96.7% (263 of 272), and 99.3% (270 of 272), respectively. In 50 image sets, two reviewers

  8. Evaluation of a standard breast tangent technique: a dose-volume analysis of tangential irradiation using three-dimensional tools

    International Nuclear Information System (INIS)

    Krasin, Matthew; McCall, Anne; King, Stephanie; Olson, Mary; Emami, Bahman

    2000-01-01

    Purpose: A thorough dose-volume analysis of a standard tangential radiation technique has not been published. We evaluated the adequacy of a tangential radiation technique in delivering dose to the breast and regional lymphatics, as well as dose delivered to underlying critical structures. Methods and Materials: Treatment plans of 25 consecutive women with breast cancer undergoing lumpectomy and adjuvant breast radiotherapy were studied. Patients underwent two-dimensional (2D) treatment planning followed by treatment with standard breast tangents. These 2D plans were reconstructed without modification on our three-dimensional treatment planning system and analyzed with regard to dose-volume parameters. Results: Adequate coverage of the breast (defined as 95% of the target receiving at least 95% of the prescribed dose) was achieved in 16 of 25 patients, with all patients having at least 85% of the breast volume treated to 95% of the prescribed dose. Only 1 patient (4%) had adequate coverage of the Level I axilla, and no patient had adequate coverage of the Level II axilla, Level III axilla, or the internal mammary lymph nodes. Conclusion: Three-dimensional treatment planning is superior in quantification of the dose received by the breast, regional lymphatics, and critical structures. The standard breast tangent technique delivers an adequate dose to the breast but does not therapeutically treat the regional lymph nodes in the majority of patients. If coverage of the axilla or internal mammary lymph nodes is desired, alternate beam arrangements or treatment fields will be necessary

  9. Multiparametric prostate MRI: technical conduct, standardized report and clinical use.

    Science.gov (United States)

    Manfredi, Matteo; Mele, Fabrizio; Garrou, Diletta; Walz, Jochen; Fütterer, Jurgen J; Russo, Filippo; Vassallo, Lorenzo; Villers, Arnauld; Emberton, Mark; Valerio, Massimo

    2018-02-01

    Multiparametric prostate MRI (mp-MRI) is an emerging imaging modality for diagnosis, characterization, staging, and treatment planning of prostate cancer (PCa). The technique, results reporting, and its role in clinical practice have been the subject of significant development over the last decade. Although mp-MRI is not yet routinely used in the diagnostic pathway, almost all urological guidelines have emphasized the potential role of mp-MRI in several aspects of PCa management. Moreover, new MRI sequences and scanning techniques are currently under evaluation to improve the diagnostic accuracy of mp-MRI. This review presents an overview of mp-MRI, summarizing the technical applications, the standardized reporting systems used, and their current roles in various stages of PCa management. Finally, this critical review also reports the main limitations and future perspectives of the technique.

  10. A new method of real-time skin dose visualization. Clinical evaluation of fluoroscopically guided interventions

    Energy Technology Data Exchange (ETDEWEB)

    Boujan, Fazel [Hopital Hautepierre, Service d' Imagerie 2 - Neuroradiologie, Strasbourg (France); University Hospitals of Strasbourg, Division of Neurointerventional Radiology, Imaging Department, Strasbourg (France); Clauss, Nicolas; Mertz, Luc [University Hospitals of Strasbourg, Division of Radiation Physics and Radiation Safety, Imaging Department, Strasbourg (France); Santos, Emilie; Boon, Sjirk; Schouten, Gerard [Philips Healthcare, Best (Netherlands); Dietemann, Jean-Louis [University Hospitals of Strasbourg, Division of Neuroradiology and Neurointerventional, Imaging Department, Strasbourg (France)

    2014-11-15

    We have conducted a prospective study to clinically evaluate a new radiation dose observing tool that displays patient's peak skin dose (PSD) map in real time. The skin dose map (SDM) prototype quantifies the air kerma based on exposure parameters from the X-ray system. The accuracy of this prototype was evaluated with radiochromic films, which were used as a mean for PSD measurement. The SDM is a reliable tool that provides an accurate PSD estimation and location. SDM also has many advantages over the radiochromic films, such as real-time dose evaluation and easy access to critical operational parameters for physicians and technicians. (orig.)

  11. Noncontrast chest computed tomography immediately after transarterial chemoembolization in patients with hepatocellular carcinoma: clinical benefits and effect of radiation reduction on image quality in low-dose scanning.

    Science.gov (United States)

    Choi, Joon-Il; Kim, Hyun Beom; Kim, Min Ju; Lee, Jong Seok; Koh, Young Whan; An, Sang Bu; Ko, Heung-kyu; Park, Joong-Won

    2011-11-01

    To evaluate the clinical benefits of noncontrast chest computed tomography (CT) immediately after transarterial chemoembolization in patients with hepatocellular carcinoma and to assess the effect of radiation reduction on image quality in low-dose scanning. From June to October 2010, we performed standard-dose, noncontrast chest CTs immediately after transarterial chemoembolization in 160 patients and low-dose CTs in 88 patients. We reviewed the entire noncontrast chest CTs and follow-up CTs to reveal the clinical benefits of CT evaluation immediately after transarterial chemoembolization. Using two independent readers, we also retrospectively evaluated the radiation dose and image quality in terms of the image noise, contrast between the liver parenchyma and iodized oil and diagnostic acceptability for the evaluation of treatment response after transarterial chemoembolization. In 5.2% of the patients, additional treatment was performed immediately after the interpretation of the noncontrast chest CT, and additional pulmonary lesions were found in 8.5% of the patients. The measured mean dose-length product for the low-dose scanning was 18.4% of that of the standard-dose scanning. The image noise was significantly higher with the low-dose scanning (pbenefits for immediate decision making and detecting pulmonary lesions. Low-dose, noncontrast chest CTs immediately after transarterial chemoembolization consistently provide diagnostically acceptable images and information on treatment response in patients who have undergone transarterial chemoembolization. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  12. Maximal safe dose of I-131 after failure of standard fixed dose therapy in patients with differentiated thyroid carcinoma

    International Nuclear Information System (INIS)

    Lee, Jong-Jin; Chung, June-Key; Kim, Sung-Eun; Kang, Won-Jun; Park, Do-Joon; Lee, Dong-Soo; Cho, Bo-Youn; Lee, Myung-Chul

    2008-01-01

    The maximal safe dose (MSD) on the basis of bone marrow irradiation levels allows the delivery of a large amount of I-131 to thyroid cancer tissue. The efficacy of MSD therapy in differentiated metastatic thyroid cancers that persisted after conventional fixed dose therapy is investigated. Forty-seven differentiated thyroid carcinoma patients with non-responsive residual disease despite repetitive fixed dose I-131 therapy were enrolled in this study. Their postoperative pathologies were 43 papillary carcinomas and 4 follicular carcinomas. The MSD was calculated with the Memorial Sloan-Kettering Cancer Center protocol using serial blood samples. The MSDs were administered at intervals of 6 months. Treatment responses were evaluated using I-131 whole-body scans and serum thyroglobulin measurements. The mean calculated MSD was 12.5±2.1 GBq (339.6±57.5 mCi). Of the 46 patients, 7 (14.9%) showed complete remission, 15 (31.9%) partial remission, 19 (40.4%) stable disease, and 6 (12.8%) disease progression. Of the patients who showed complete or partial remission, 15 (65%) showed response after the first MSD session and 6 (26%) showed response after the second session. Twenty-nine patients (62%) experienced transient cytopenia after therapy, but three did not recover to the baseline level. The maximal safe dose provides an effective means of treatment in patients who failed to respond adequately to conventional fixed dose therapy. I-131 MSD therapy can be considered in patients who fail fixed dose therapy. (author)

  13. Randomised clinical trial of early specialist palliative care plus standard care versus standard care alone in patients with advanced cancer

    DEFF Research Database (Denmark)

    Grønvold, Mogens; Petersen, Morten Aagaard; Damkier, Anette

    2017-01-01

    Palliative Care Trial (DanPaCT) (ClinicalTrials.gov NCT01348048) is a multicentre randomised clinical trial comparing early referral to a specialist palliative care team plus standard care versus standard care alone. The planned sample size was 300. At five oncology departments, consecutive patients...

  14. Robust, standardized quantification of pulmonary emphysema in low dose CT exams.

    Science.gov (United States)

    Ceresa, Mario; Bastarrika, Gorka; de Torres, Juan P; Montuenga, Luis M; Zulueta, Javier J; Ortiz-de-Solorzano, Carlos; Muñoz-Barrutia, Arrate

    2011-11-01

    The aim of this study was to present and evaluate a fully automated system for emphysema quantification on low-dose computed tomographic images. The platform standardizes emphysema measurements against changes in the reconstruction algorithm and slice thickness. Emphysema was quantified in 149 patients using a fully automatic, in-house developed software (the Robust Automatic On-Line Pulmonary Helper). The accuracy of the system was evaluated against commercial software, and its reproducibility was assessed using pairs of volume-corrected images taken 1 year apart. Furthermore, to standardize quantifications, the effect of changing the reconstruction parameters was modeled using a nonlinear fit, and the inverse of the model function was then applied to the data. The association between quantifications and pulmonary function testing was also evaluated. The accuracy of the in-house software compared to that of commercial software was measured using Spearman's rank correlation coefficient, the mean difference, and the intrasubject variability. Agreement between the methods was studied using Bland-Altman plots. To assess the reproducibility of the method, intraclass correlation coefficients and Bland-Altman plots were used. The statistical significance of the differences between the standardized data and the reference data (soft-tissue reconstruction algorithm B40f; slice thickness, 1 mm) was assessed using a paired two-sample t test. The accuracy of the method, measured as intrasubject variability, was 3.86 mL for pulmonary volume, 0.01% for emphysema index, and 0.39 Hounsfield units for mean lung density. Reproducibility, assessed using the intraclass correlation coefficient, was >0.95 for all measurements. The standardization method applied to compensate for variations in the reconstruction algorithm and slice thickness increased the intraclass correlation coefficients from 0.87 to 0.97 and from 0.99 to 1.00, respectively. The correlation of the standardized

  15. Iterative reconstruction and automatic tube voltage selection reduce clinical CT radiation doses and image noise.

    Science.gov (United States)

    O'Hora, L; Foley, S J

    2018-02-01

    Computed Tomography (CT) use has increased in recent years with trends indicating increasing population doses as a result. Optimization of clinical radiation doses through technological developments has demonstrated potential to reduce patient dose from CT. This study aimed to quantify these dose reductions across a large clinical cohort. Patient cohort was divided into three groups, assigned by CT optimisation technique. Group one underwent scanning with automated tube current modulation only. Group two underwent scanning with automated tube current modulation and iterative reconstruction and group three underwent scanning with automated tube current modulation, iterative reconstruction and automatic tube voltage modulation. Patient dose length product doses were retrospectively collected for the three groups. Clinical radiation doses between the groups were compared for four common CT examinations (Brain, pulmonary angiography, abdomen and thorax abdomen pelvis scans). Of 4011 patients, group one comprised of 1643 patients (40.96%), group two 1077 patients (26.85%) and group three 1291 patients (32.19%). No differences were found when comparing AP diameter between groups (p ≥ 0.05). Statistically significant dose reductions of 16-31% were achieved using iterative reconstruction alone (p = 0.001) and 24-42% with both iterative reconstruction and automatic tube voltage selection (p = 0.001). Objective noise improved when iterative reconstruction was used (p staff and procedural protocols remaining consistent throughout. Dose reductions are likely to reflect the clinical dose reducing potential of the optimization software investigated. Copyright © 2017 The College of Radiographers. Published by Elsevier Ltd. All rights reserved.

  16. A Comparison of Radiation Dose Between Standard and 3D Angiography in Congenital Heart Disease

    Energy Technology Data Exchange (ETDEWEB)

    Manica, João Luiz Langer, E-mail: joca.pesquisa@gmail.com; Borges, Mônica Scott; Medeiros, Rogério Fachel de; Fischer, Leandro dos Santos; Broetto, Gabriel; Rossi, Raul Ivo Filho [Instituto de Cardiologia / Fundação Universitária de Cardiologia, Porto Alegre, RS (Brazil)

    2014-08-15

    The use of three-dimensional rotational angiography (3D-RA) to assess patients with congenital heart diseases appears to be a promising technique despite the scarce literature available. The objective of this study was to describe our initial experience with 3D-RA and to compare its radiation dose to that of standard two-dimensional angiography (2D-SA). Between September 2011 and April 2012, 18 patients underwent simultaneous 3D-RA and 2D-SA during diagnostic cardiac catheterization. Radiation dose was assessed using the dose-area-product (DAP). The median patient age and weight were 12.5 years and 47.5 Kg, respectively. The median DAP of each 3D-RA acquisition was 1093µGy.m{sup 2} and 190µGy.m{sup 2} for each 2D-SA acquisition (p<0.01). In patients weighing more than 45Kg (n=7), this difference was attenuated but still significant (1525 µGy.m{sup 2} vs.413µGy.m{sup 2}, p=0.01). No difference was found between one 3D-RA and three 2D-SA (1525µGy.m{sup 2} vs.1238 µGy.m{sup 2}, p = 0.575) in this population. This difference was significantly higher in patients weighing less than 45Kg (n=9) (713µGy.m{sup 2} vs.81µGy.m{sup 2}, P = 0.008), even when comparing one 3D-RA with three 2D-SA (242µGy.m{sup 2}, respectively, p<0.008). 3D-RA was extremely useful for the assessment of conduits of univentricular hearts, tortuous branches of the pulmonary artery, and aorta relative to 2D-SA acquisitions. The radiation dose of 3D-RA used in our institution was higher than those previously reported in the literature and this difference was more evident in children. This type of assessment is of paramount importance when starting to perform 3D-RA.

  17. Standard and Low-dose Hormone Therapy for Postmenopausal Women—Focus on the Breast

    Directory of Open Access Journals (Sweden)

    Peng-Hui Wang

    2007-06-01

    can be used with symptomatic menopausal women, but is worthy of further evaluation because we found the following potential benefits, including (i low-dose oral EPT appears to be effective for the alleviation of climacteric symptoms; (ii it has a good tolerability profile with a low incidence of the most common and problematic side effects, such as breast tenderness and an increased mammographic density. Altogether, when compared with the standard dose HT, physicians may prefer to use low-dose HT initially in managing the climacteric symptoms of postmenopausal women. Time will prove.

  18. Comparison of the NMIJ and the ARPANSA standards for absorbed dose to water in high-energy photon beams.

    Science.gov (United States)

    Shimizu, M; Morishita, Y; Kato, M; Tanaka, T; Kurosawa, T; Takata, N; Saito, N; Ramanathan, G; Harty, P D; Oliver, C; Wright, T; Butler, D J

    2015-04-01

    The authors report the results of an indirect comparison of the standards of absorbed dose to water in high-energy photon beams from a clinical linac and (60)Co radiation beam performed between the National Metrology Institute of Japan (NMIJ) and the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA). Three ionisation chambers were calibrated by the NMIJ in April and June 2013 and by the ARPANSA in May 2013. The average ratios of the calibration coefficients for the three ionisation chambers obtained by the NMIJ to those obtained by the ARPANSA were 0.9994, 1.0040 and 1.0045 for 6-, 10- and 15-MV (18 MV at the ARPANSA) high-energy photon beams, respectively. The relative standard uncertainty of the value was 7.2 × 10(-3). The ratio for (60)Co radiation was 0.9986(66), which is consistent with the results published in the key comparison of BIPM.RI(I)-K4. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  19. Determining clinical photon beam spectra from measured depth dose with the Cimmino algorithm

    International Nuclear Information System (INIS)

    Bloch, P.; Altschuler, M.D.; Bjaerngard, B.E.; Kassaee, A.; McDonough, J.

    2000-01-01

    A method to determine the spectrum of a clinical photon beam from measured depth-dose data is described. At shallow depths, where the range of Compton-generated electrons increases rapidly with photon energy, the depth dose provides the information to discriminate the spectral contributions. To minimize the influence of contaminating electrons, small (6x6cm2 ) fields were used. The measured depth dose is represented as a linear combination of basis functions, namely the depth doses of monoenergetic photon beams derived by Monte Carlo simulations. The weights of the basis functions were obtained with the Cimmino feasibility algorithm, which examines in each iteration the discrepancy between predicted and measured depth dose. For 6 and 15 MV photon beams of a clinical accelerator, the depth dose obtained from the derived spectral weights was within about 1% of the measured depth dose at all depths. Because the problem is ill conditioned, solutions for the spectrum can fluctuate with energy. Physically realistic smooth spectra for these photon beams appeared when a small margin (about ±1%) was attributed to the measured depth dose. The maximum energy of both derived spectra agreed with the measured energy of the electrons striking the target to within 1 MeV. The use of a feasibility method on minimally relaxed constraints provides realistic spectra quickly and interactively. (author)

  20. Comparison between Clinically Used Irregular Fields Shielded by Cerrobend and Standard Lead Blocks

    Directory of Open Access Journals (Sweden)

    Farajollahi A. R.

    2015-06-01

    Full Text Available Introduction: In radiation therapy centers across Iran, protection of normal tissues is usually accomplished by either Cerrobend or lead block shielding. In this study, the influence of these two shielding methods on central axis dose distribution of photon beam a Cobalt unit was investigated in clinical conditions. Materials and Methods: All measurements were performed for 60Co γ-ray beams and the Cerrobend blocks were fabricated by commercial Cerrobend materials. Standard lead block shields belonged to Cobalt unit. Data was collected through a calibrated ionization chamber, relative dosimetry systems and a TLD dosimetery. Results: Results of the percent depth dose (PDD measurements at depths of 0.5, 1, 5, 10, 15 and 20 cm for 23 different field sizes of patients with head and neck cancer showed no significant differences between lead and Cerrobend shielding methods. Measurement results of absolute dosimetry in depths of 1.5, 3, 5, 7, 10 and 12 cm also showed no significant differences between these two shielding methods. The same results were obtained by TLD dosimetry on patient skin. Conclusion: Use of melt shielding methods is a very easy and fast shield-making technique with no differences in PDD, absolute and skin dose between lead and Cerrobend block shielding methods.

  1. Key clinical beam parameters for nanoparticle-mediated radiation dose amplification.

    Science.gov (United States)

    Detappe, Alexandre; Kunjachan, Sijumon; Drané, Pascal; Kotb, Shady; Myronakis, Marios; Biancur, Douglas E; Ireland, Thomas; Wagar, Matthew; Lux, Francois; Tillement, Olivier; Berbeco, Ross

    2016-09-23

    As nanoparticle solutions move towards human clinical trials in radiation therapy, the influence of key clinical beam parameters on therapeutic efficacy must be considered. In this study, we have investigated the clinical radiation therapy delivery variables that may significantly affect nanoparticle-mediated radiation dose amplification. We found a benefit for situations which increased the proportion of low energy photons in the incident beam. Most notably, "unflattened" photon beams from a clinical linear accelerator results in improved outcomes relative to conventional "flat" beams. This is measured by significant DNA damage, tumor growth suppression, and overall improvement in survival in a pancreatic tumor model. These results, obtained in a clinical setting, clearly demonstrate the influence and importance of radiation therapy parameters that will impact clinical radiation dose amplification with nanoparticles.

  2. Clinical standard of neurosurgical disorder. (9) Disturbance of consciousness

    International Nuclear Information System (INIS)

    Ohta, Tomio

    2009-01-01

    Functional diagnosis of consciousness disturbance (CD) in acute and chronic stages is becoming more important along with the progress of morphological diagnosis by CT and MRI at the stroke and brain lesion. Here described and discussed are the definition of consciousness and unconsciousness, cause and scoring of CD by various scaling and clinical significance of the scale for therapy. The author's definition for consciousness is based on patients' self identity and orientation. The above CD is essentially caused by the increased intracranial pressure, which is evaluable by imaging as the increase is derived from the herniation by tumor or edema mainly through transtentorial (uncal, hippocampal) and/or foraminal (cerebellar tonsillar) pathways. Scaling of CD stands on three factors of validity, reliability and feasibility, of which standards of JCS (Japan coma scale) and GCS (Glasgow coma scale) have been widely employed. In discussion of merit/demerit of JCS and GCS, the author et al. have proposed a new scale ECS (emergency coma scale) with 3 levels of digit code for patient's response and behavior under CD. Therapeutic outcome is greatly affected by acute CD levels evaluable by scaling, in which awakening/alertness relates with mortality, and local symptom/consciousness, with morbidity. ECS is now globally getting around. (K.T.)

  3. International intercomparison of standards for low collision kerma rates in air by means of low dose TLD techniques

    International Nuclear Information System (INIS)

    Spanne, P.; Carlsson, C.A.; Carlsson, G.A.

    1984-01-01

    An international intercomparison of standards for calibration of radiation protection instruments is described. The intercomparison involved collision kerma rates in air in the range 5.7 to 7.400 μGy.h -1 and was performed using low dose TLD techniques with TL-LiF dosemeters. The dosemeters were specifically tested with regard to their dose rate dependence, but none was found. (author)

  4. Characterization of an absorbed dose standard in water through ionometric methods

    International Nuclear Information System (INIS)

    Vargas V, M.X.

    2003-01-01

    In this work the unit of absorbed dose at the Secondary Standard Dosimetry Laboratory (SSDL) of Mexico, is characterized by means of the development of a primary standard of absorbed dose to water, D agua . The main purpose is to diminish the uncertainty in the service of dosimetric calibration of ionization chambers (employed in radiotherapy of extemal beams) that offers this laboratory. This thesis is composed of seven chapters: In Chapter 1 the position and justification of the problem is described, as well as the general and specific objectives. In Chapter 2, a presentation of the main quantities and units used in dosimetry is made, in accordance with the recommendations of the International Commission on Radiation Units and Measurements (ICRU) that establish the necessity to have a coherent system with the international system of units and dosimetric quantities. The concepts of equilibrium and transient equilibrium of charged particles (TCPE) are also presented, which are used later in the quantitative determination of D agua . Finally, since the proposed standard of D agua is of ionometric type, an explanation of the Bragg-Gray and Spencer-Attix cavity theories is made. These theories are the foundation of this type of standards. On the other hand, to guarantee the complete validity of the conditions demanded by these theories it is necessary to introduce correction factors. These factors are determined in Chapters 5 and 6. Since for the calculation of the correction factors Monte Carlo (MC) method is used in an important way, in Chapter 3 the fundamental concepts of this method are presented; in particular the principles of the code MCNP4C [Briesmeister 2000] are detailed, making emphasis on the basis of electron transport and variance reduction techniques used in this thesis. Because a phenomenological approach is carried out in the development of the standard of D agua , in Chapter 4 the characteristics of the Picker C/9 unit, the ionization chamber type

  5. A review of the clinical experience in pulsed dose rate brachytherapy.

    Science.gov (United States)

    Balgobind, Brian V; Koedooder, Kees; Ordoñez Zúñiga, Diego; Dávila Fajardo, Raquel; Rasch, Coen R N; Pieters, Bradley R

    2015-01-01

    Pulsed dose rate (PDR) brachytherapy is a treatment modality that combines physical advantages of high dose rate (HDR) brachytherapy with the radiobiological advantages of low dose rate brachytherapy. The aim of this review was to describe the effective clinical use of PDR brachytherapy worldwide in different tumour locations. We found 66 articles reporting on clinical PDR brachytherapy including the treatment procedure and outcome. Moreover, PDR brachytherapy has been applied in almost all tumour sites for which brachytherapy is indicated and with good local control and low toxicity. The main advantage of PDR is, because of the small pulse sizes used, the ability to spare normal tissue. In certain cases, HDR resembles PDR brachytherapy by the use of multifractionated low-fraction dose.

  6. Determination of electron clinical spectra from percentage depth dose (PDD) curves by classical simulated annealing method

    International Nuclear Information System (INIS)

    Visbal, Jorge H. Wilches; Costa, Alessandro M.

    2016-01-01

    Percentage depth dose of electron beams represents an important item of data in radiation therapy treatment since it describes the dosimetric properties of these. Using an accurate transport theory, or the Monte Carlo method, has been shown obvious differences between the dose distribution of electron beams of a clinical accelerator in a water simulator object and the dose distribution of monoenergetic electrons of nominal energy of the clinical accelerator in water. In radiotherapy, the electron spectra should be considered to improve the accuracy of dose calculation since the shape of PDP curve depends of way how radiation particles deposit their energy in patient/phantom, that is, the spectrum. Exist three principal approaches to obtain electron energy spectra from central PDP: Monte Carlo Method, Direct Measurement and Inverse Reconstruction. In this work it will be presented the Simulated Annealing method as a practical, reliable and simple approach of inverse reconstruction as being an optimal alternative to other options. (author)

  7. Islet Oxygen Consumption Rate (OCR Dose Predicts Insulin Independence in Clinical Islet Autotransplantation.

    Directory of Open Access Journals (Sweden)

    Klearchos K Papas

    Full Text Available Reliable in vitro islet quality assessment assays that can be performed routinely, prospectively, and are able to predict clinical transplant outcomes are needed. In this paper we present data on the utility of an assay based on cellular oxygen consumption rate (OCR in predicting clinical islet autotransplant (IAT insulin independence (II. IAT is an attractive model for evaluating characterization assays regarding their utility in predicting II due to an absence of confounding factors such as immune rejection and immunosuppressant toxicity.Membrane integrity staining (FDA/PI, OCR normalized to DNA (OCR/DNA, islet equivalent (IE and OCR (viable IE normalized to recipient body weight (IE dose and OCR dose, and OCR/DNA normalized to islet size index (ISI were used to characterize autoislet preparations (n = 35. Correlation between pre-IAT islet product characteristics and II was determined using receiver operating characteristic analysis.Preparations that resulted in II had significantly higher OCR dose and IE dose (p<0.001. These islet characterization methods were highly correlated with II at 6-12 months post-IAT (area-under-the-curve (AUC = 0.94 for IE dose and 0.96 for OCR dose. FDA/PI (AUC = 0.49 and OCR/DNA (AUC = 0.58 did not correlate with II. OCR/DNA/ISI may have some utility in predicting outcome (AUC = 0.72.Commonly used assays to determine whether a clinical islet preparation is of high quality prior to transplantation are greatly lacking in sensitivity and specificity. While IE dose is highly predictive, it does not take into account islet cell quality. OCR dose, which takes into consideration both islet cell quality and quantity, may enable a more accurate and prospective evaluation of clinical islet preparations.

  8. The clinical meaning of radiodermatitis considering the surface dose of supervoltage electron beam

    International Nuclear Information System (INIS)

    Hiraki, Tatsunosuke; Rikimaru, Shigeho; Kakishita, Masao; Kuranishi, Makoto.

    1975-01-01

    In our experience using supervoltage betatron electron beam, the skin surface dose of the electron decreased when the energy became either greater of less than 18 MeV. When we considered 18 MeV to be a 100% dose, the dose with 4 MeV, which was the least amount, corresponded to 81% of the dose. The skin surface dose of 10 MeV betatron electrons or more became greater than the 90% standard tumor dose. An external irradiation of more than 10 MeV should not be applied to neoplasms of which the curative ratio is less than 1.0. Therefore another methods such as intraoperative irradiation, should be used. The surface skin dose about 4-6 MeV betatron postoperative irradiation, particularly after resection of breast cancer, was less than the skin dose with 10 MeV. Close care should be taken to prevent hot lesions which are caused by duplication of irradiation fields. It should be kept in mind that the late effects of hot lesions caused by electron beam irradiation with an energy of 10 MeV or more are serious. (Kashu, E.)

  9. High-dose dual therapy is superior to standard first-line or rescue therapy for Helicobacter pylori infection.

    Science.gov (United States)

    Yang, Jyh-Chin; Lin, Chun-Jung; Wang, Hong-Long; Chen, Jin-De; Kao, John Y; Shun, Chia-Tung; Lu, Chien-Wei; Lin, Bor-Ru; Shieh, Ming-Jium; Chang, Ming-Chu; Chang, Yu-Ting; Wei, Shu-Chen; Lin, Lin-Chih; Yeh, Wen-Chun; Kuo, Jen-Shin; Tung, Chien-Chih; Leong, Yew-Loong; Wang, Teh-Hong; Wong, Jau-Min

    2015-05-01

    The efficacy of treatment of Helicobacter pylori infection has decreased steadily because of increasing resistance to clarithromycin, metronidazole, and levofloxacin. Resistance to amoxicillin is generally low, and high intragastric pH increases the efficacy of amoxicillin, so we investigated whether a combination of a high-dose proton pump inhibitor and amoxicillin (dual therapy) was more effective than standard first-line or rescue therapies in eradicating H pylori. We performed a large-scale multihospital trial to compare the efficacy of a high-dose dual therapy (HDDT) with that of standard therapies in treatment-naive (n = 450) or treatment-experienced (n = 168) patients with H pylori infection. Treatment-naive patients were randomly assigned to groups given HDDT (rabeprazole 20 mg and amoxicillin 750 mg, 4 times/day for 14 days, group A1), sequential therapy for 10 days (group B1), or clarithromycin-containing triple therapy for 7 days (group C1). Treatment-experienced patients were randomly assigned to groups given HDDT for 14 days (group A2), sequential therapy for 10 days (B2), or levofloxacin-containing triple therapy for 7 days (C2). H pylori infection was detected by using the (13)C-urea breath test. We evaluated factors associated with treatment outcomes. In the intention-to-treat analysis, H pylori was eradicated in 95.3% of patients in group A1 (95% confidence interval [CI], 91.9%-98.8%), 85.3% in B1 (95% CI, 79.6%-91.1%), and 80.7% in group C1 (95% CI, 74.3%-87.1%). Infection was eradicated in 89.3% of patients in group A2 (95% CI, 80.9%-97.6%), 51.8% in group B2 (95% CI, 38.3%-65.3%), and 78.6% (95% CI, 67.5%-89.7%) in group C2. The efficacy of HDDT was significantly higher than that of currently recommended regimens, irrespective of CYP2C19 genotype. Bacterial resistance to drugs was associated with treatment failure. There were no significant differences between groups in adverse events or patient adherence. HDDT is superior to standard regimens

  10. Comparison of measured and calculated contralateral breast doses in whole breast radiotherapy for VMAT and standard tangent techniques

    International Nuclear Information System (INIS)

    Tse, T.L.J; Bromley, R.; Booth, J.; Gray, A.

    2011-01-01

    Full text: Objective This study aims to evaluate the accuracy of calculated dose with the Eclipse analytical anisotropic algorithm (AAA) for contralateral breast (CB) in left-sided breast radiotherapy for dual-arc VMA T and standard wedged tangent (SWT) techniques. Methods and materials Internal and surface CB doses were measured with EBT2 film in an anthropomorphic phantom mounted with C-cup and D-cup breasts. The measured point dose was approximated by averaging doses over the 4 x 4 mm 2 central region of each 2 x 2 cm2 piece of film. The dose in the target region of the breast was also measured. The measured results were compared to AAA calculations with calculation grids of I, 2.5 and 5 mm. Results In SWT plans, the average ratios of calculation to measurement for internal doses were 0.63 ± 0.081 and 0.5 I ± 0.28 in the medial and lateral aspects, respectively. Corresponding ratios for surface doses were 0.88 ± 0.22 and 0.38 ± 0.38. In VMAT plans, however, the calculation accuracies showed little dependence on the measurement locations, the ratios were 0.78 ± O. I I and 0.81 ± 0.085 for internal and surface doses. In general, finer calculation resolutions did not inevitably improve the dose estimates of internal doses. For surface doses, using smaller grid size I mm could improve the calculation accuracies on the medial but not the lateral aspects of CB. Conclusion In all plans, AAA had a tendency to underestimate both internal and surface CB doses. Overall, it produces more accurate results in VMAT than SWT plans.

  11. MR imaging in recurrent pain after back surgery. A comparative study using standard and high doses of gadolinium contrast agents

    International Nuclear Information System (INIS)

    Aakeson, P.; Jonsson, E.; Holtaas, S.

    1996-01-01

    Purpose: To compare the diagnostic results following injection of (a) a high dose (0.3 mmol/kg b.w.) of gadodiamide injection and (b) the standard dose (0.1 mmol/kg b.w.) of Gd-DTPA, in patients with recurrent symptoms after surgery for lumbar disc herniation. Material and Methods: Twenty patients with recurrent or sustained symptoms after surgery for lumbar disc herniations were examined. MR imaging (0.3 T) was first performed before and after Gd-DTPA at 0.1 mmol/kg b.w., and then within one month (17 patients) or within 3 months (3 patients) before and after gadodiamide injection at 0.3 mmol/kg b.w. The examinations were first evaluated by 2 neuroradiologists blinded to dose but not to patient as the images were presented in pairs. Six months later the same investigators evaluated the examinations again, this time blinded to both dose and patient. Results: At the evaluation in pairs (with the investigators blinded to dose only) the high-dose examinations were considered the most informative (p=0.05). However, at the later evaluation (with the investigators blinded both to dose and patient) no significant difference between high and standard dose was found regarding diagnosis or diagnostic certainty. Conclusion: In this study the high-dose contrast enhancement of MR imaging at 0.3 T did not increase the diagnostic information for differentiating between scar and recurrent hernia. The high-dose images were considered more informative when evaluated in pairs, but gave no additional or different information when evaluated separately. The study also indicated that comparisons in pairs should be interpreted with caution. (orig.)

  12. MR imaging in recurrent pain after back surgery. A comparative study using standard and high doses of gadolinium contrast agents

    Energy Technology Data Exchange (ETDEWEB)

    Aakeson, P. [Univ. Hospital, Lund (Sweden). Dept. of Radiology; Annertz, M. [Univ. Hospital, Lund (Sweden). Dept. of Radiology; Kristoffersen, D.T. [Nycomed Imaging AS, Oslo (Norway); Jonsson, E. [Nycomed AB, Stockholm (Sweden); Holtaas, S. [Univ. Hospital, Lund (Sweden). Dept. of Radiology

    1996-11-01

    Purpose: To compare the diagnostic results following injection of (a) a high dose (0.3 mmol/kg b.w.) of gadodiamide injection and (b) the standard dose (0.1 mmol/kg b.w.) of Gd-DTPA, in patients with recurrent symptoms after surgery for lumbar disc herniation. Material and Methods: Twenty patients with recurrent or sustained symptoms after surgery for lumbar disc herniations were examined. MR imaging (0.3 T) was first performed before and after Gd-DTPA at 0.1 mmol/kg b.w., and then within one month (17 patients) or within 3 months (3 patients) before and after gadodiamide injection at 0.3 mmol/kg b.w. The examinations were first evaluated by 2 neuroradiologists blinded to dose but not to patient as the images were presented in pairs. Six months later the same investigators evaluated the examinations again, this time blinded to both dose and patient. Results: At the evaluation in pairs (with the investigators blinded to dose only) the high-dose examinations were considered the most informative (p=0.05). However, at the later evaluation (with the investigators blinded both to dose and patient) no significant difference between high and standard dose was found regarding diagnosis or diagnostic certainty. Conclusion: In this study the high-dose contrast enhancement of MR imaging at 0.3 T did not increase the diagnostic information for differentiating between scar and recurrent hernia. The high-dose images were considered more informative when evaluated in pairs, but gave no additional or different information when evaluated separately. The study also indicated that comparisons in pairs should be interpreted with caution. (orig.).

  13. Consolidating duodenal and small bowel toxicity data via isoeffective dose calculations based on compiled clinical data.

    Science.gov (United States)

    Prior, Phillip; Tai, An; Erickson, Beth; Li, X Allen

    2014-01-01

    To consolidate duodenum and small bowel toxicity data from clinical studies with different dose fractionation schedules using the modified linear quadratic (MLQ) model. A methodology of adjusting the dose-volume (D,v) parameters to different levels of normal tissue complication probability (NTCP) was presented. A set of NTCP model parameters for duodenum toxicity were estimated by the χ(2) fitting method using literature-based tolerance dose and generalized equivalent uniform dose (gEUD) data. These model parameters were then used to convert (D,v) data into the isoeffective dose in 2 Gy per fraction, (D(MLQED2),v) and convert these parameters to an isoeffective dose at another NTCP (D(MLQED2'),v). The literature search yielded 5 reports useful in making estimates of duodenum and small bowel toxicity. The NTCP model parameters were found to be TD50(1)(model) = 60.9 ± 7.9 Gy, m = 0.21 ± 0.05, and δ = 0.09 ± 0.03 Gy(-1). Isoeffective dose calculations and toxicity rates associated with hypofractionated radiation therapy reports were found to be consistent with clinical data having different fractionation schedules. Values of (D(MLQED2'),v) between different NTCP levels remain consistent over a range of 5%-20%. MLQ-based isoeffective calculations of dose-response data corresponding to grade ≥2 duodenum toxicity were found to be consistent with one another within the calculation uncertainty. The (D(MLQED2),v) data could be used to determine duodenum and small bowel dose-volume constraints for new dose escalation strategies. Copyright © 2014 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.

  14. Patient radiation dose in some dental radiography clinics in Khartoum, Sudan

    International Nuclear Information System (INIS)

    Mohamed, Aziza Hamed Abdelgadir

    2016-01-01

    Patient dose audit is an important tool for quality control and it is important for monitoring patient exposure. The DAP meter has proved to be an easy and accurate tool for patient dosimetry and for establishment of diagnostic reference levels in dental radiology. The objective of this study was measure patient dose in dental radiography in some dental radiography clinics in Khartoum. The study was performed in five dental clinics comprising six panoramic and six intraoral dental radiography devices in Khartoum state. The incident surface air kerma (k i ) and dose area product were measured for intraoral and panoramic dental examinations, respectively for digital and film imaging modalities. Incident surface air kerma (k i ) was measured using calibrated dose rate meter where dose area product were determined from dose width product (DWP) measured using 3 cc pencil type CT ionization chamber. For intraoral examinations, the maximum, average and minimum, (1.95, 1.48, and 1.24) mGy, (5.84, 4.54, and 3.6) mGy for digital and imaging, respectively. This result was lower in digital in traol and higher in film imaging. The result for panoramic examination calculated dose area product (DAP) mean value for adult and pediatric was (103, 70.42) mGy cm 2 , respectively, where the dose for digital imaging was highest in two centers, compared to previous study. Increased patient dose in intraoral dental radiography could partially be explained by the use of circular collimators. or intraoral x-ray equipment the downward trend in patient dose can only be continue, a through the adoption of digital imaging methods. Our results are relatively higher in digital panoramic dental examinations. It is important to point out that non of the dental units under study were covered by regular quality assurance programme.(Author)

  15. Actual survey of dose evaluation method for standardization of radiation therapy techniques. With special reference to display method of radiation doses

    International Nuclear Information System (INIS)

    Kumagai, Kozo; Yoshiura, Takao; Izumi, Takashi; Araki, Fujio; Takada, Takuo; Jingu, Kenichi.

    1994-01-01

    This report presents the results of questionnaire survey for actual conditions of radiation therapy, which was conducted with the aim of establishing the standardization of radiation therapy techniques. Questionnaires were sent to 100 facilities in Japan, and 86 of these answered, consisting of 62 university hospitals, 2 national hospitals, 14 cancer centers, 4 prefectural or municipal hospitals, and 4 other hospitals. In addition to electron beam therapy, the following typical diseases for radiation therapy were selected as standard irradiation models: cancers of the larynx, esophagus, breast, and uterine cervix, and malignant lymphomas. According to these models, questionnaire results are analyzed in terms of the following four items: (1) irradiation procedures, (2) energy used for radiotherapy, (3) the depth for calculating target absorption doses, and (4) points for displaying target absorption doses. (N.K.)

  16. Sub-milliSievert (sub-mSv) CT colonography: a prospective comparison of image quality and polyp conspicuity at reduced-dose versus standard-dose imaging

    International Nuclear Information System (INIS)

    Lubner, Meghan G.; Pooler, B.D.; Kitchin, Douglas R.; Kim, David H.; Munoz del Rio, Alejandro; Pickhardt, Perry J.; Tang, Jie; Li, Ke; Chen, Guang-Hong

    2015-01-01

    To prospectively compare reduced-dose (RD) CT colonography (CTC) with standard-dose (SD) imaging using several reconstruction algorithms. Following SD supine CTC, 40 patients (mean age, 57.3 years; 17 M/23 F; mean BMI, 27.2) underwent an additional RD supine examination (targeted dose reduction, 70-90 %). DLP, CTDI vol , effective dose, and SSDE were compared. Several reconstruction algorithms were applied to RD series. SD-FBP served as reference standard. Objective image noise, subjective image quality and polyp conspicuity were assessed. Mean CTDI vol and effective dose for RD series was 0.89 mGy (median 0.65) and 0.6 mSv (median 0.44), compared with 3.8 mGy (median 3.1) and 2.8 mSv (median 2.3) for SD series, respectively. Mean dose reduction was 78 %. Mean image noise was significantly reduced on RD-PICCS (24.3 ± 19HU) and RD-MBIR (19 ± 18HU) compared with RD-FBP (90 ± 33), RD-ASIR (72 ± 27) and SD-FBP (47 ± 14 HU). 2D image quality score was higher with RD-PICCS, RD-MBIR, and SD-FBP (2.7 ± 0.4/2.8 ± 0.4/2.9 ± 0.6) compared with RD-FBP (1.5 ± 0.4) and RD-ASIR (1.8 ± 0.44). A similar trend was seen with 3D image quality scores. Polyp conspicuity scores were similar between SD-FBP/RD-PICCS/RD-MBIR (3.5 ± 0.6/3.2 ± 0.8/3.3 ± 0.6). Sub-milliSievert CTC performed with iterative reconstruction techniques demonstrate decreased image quality compared to SD, but improved image quality compared to RD images reconstructed with FBP. (orig.)

  17. Once-daily dose regimen of ribavirin is interchangeable with a twice-daily dose regimen: randomized open clinical trial

    Directory of Open Access Journals (Sweden)

    Balk JM

    2015-08-01

    .05. No significant differences in the hematological profile were observed (P>0.05. Conclusion: The standard twice-daily RBV regimen is interchangeable with the once-daily regimen. The once-daily regimen will improve compliance and opens the opportunity to combine RBV with other drugs dosed once a day, in a single pill. Keywords: hepatitis C, dose regimen, ribavirin, pegylated interferon

  18. Correlation of clinical outcome to the estimated radiation dose from Boron Neutron Capture Therapy (BNCT)

    Energy Technology Data Exchange (ETDEWEB)

    Chadha, M. [Beth Israel Medical Center, NY (United States). Dept. of Radiation Oncology; Coderre, J.A.; Chanana, A.D. [Brookhaven National Lab., Upton, NY (United States)] [and others

    1996-12-31

    A phase I/II trial delivering a single fraction of BNCT using p-Boronophenylalanine-Fructose and epithermal neutrons at the the Brookhaven Medical Research Reactor was initiated in September 1994. The primary endpiont of the study was to evaluate the feasibility and safety of a given BNCT dose. The clinical outcome of the disease was a secondary endpoint of the study. The objective of this paper is to evaluate the correlation of the clinical outcome of patients to the estimated radiation dose from BNCT.

  19. Correlation of clinical outcome to the estimated radiation dose from Boron Neutron Capture Therapy (BNCT)

    International Nuclear Information System (INIS)

    Chadha, M.

    1996-01-01

    A phase I/II trial delivering a single fraction of BNCT using p-Boronophenylalanine-Fructose and epithermal neutrons at the the Brookhaven Medical Research Reactor was initiated in September 1994. The primary endpiont of the study was to evaluate the feasibility and safety of a given BNCT dose. The clinical outcome of the disease was a secondary endpoint of the study. The objective of this paper is to evaluate the correlation of the clinical outcome of patients to the estimated radiation dose from BNCT

  20. [Cerebral hemorrhage induced by low-dose streptokinase: a pharmacologic paradox? Report of a clinical case].

    Science.gov (United States)

    Fedeli, F; Skouse, D; Messina, A

    1997-01-01

    A case of an important intracranial hemorrhage after a low dose (approx. 500,000 UI) of streptokinase in a 60 year-old woman suffering from myocardial infarction is presented. Clinical, electrocardiographic, echocardiographic, lab and tomographic findings are described. The authors suggest a pharmacokinetic mechanism which could be responsible of a "paradox effect" (a powerful and dangerous effect of the drug when given in low dose) and they wonder whether in case of allergic reactions should it be better not to stop the infusion of the thrombolytic drug and be more liberal with the "symptomatic" drugs. Tha patient is still alive and the clinical conditions slowly progressing.

  1. Radiation dose to children in diagnostic radiology. Measurements and methods for clinical optimisation studies

    Energy Technology Data Exchange (ETDEWEB)

    Almen, A.J.

    1995-09-01

    A method for estimating mean absorbed dose to different organs and tissues was developed for paediatric patients undergoing X-ray investigations. The absorbed dose distribution in water was measured for the specific X-ray beam used. Clinical images were studied to determine X-ray beam positions and field sizes. Size and position of organs in the patient were estimated using ORNL phantoms and complementary clinical information. Conversion factors between the mean absorbed dose to various organs and entrance surface dose for five different body sizes were calculated. Direct measurements on patients estimating entrance surface dose and energy imparted for common X-ray investigations were performed. The examination technique for a number of paediatric X-ray investigations used in 19 Swedish hospitals was studied. For a simulated pelvis investigation of a 1-year old child the entrance surface dose was measured and image quality was estimated using a contrast-detail phantom. Mean absorbed doses to organs and tissues in urography, lung, pelvis, thoracic spine, lumbar spine and scoliosis investigations was calculated. Calculations of effective dose were supplemented with risk calculations for special organs e g the female breast. The work shows that the examination technique in paediatric radiology is not yet optimised, and that the non-optimised procedures contribute to a considerable variation in radiation dose. In order to optimise paediatric radiology there is a need for more standardised methods in patient dosimetry. It is especially important to relate measured quantities to the size of the patient, using e g the patient weight and length. 91 refs, 17 figs, 8 tabs.

  2. Radiation dose to children in diagnostic radiology. Measurements and methods for clinical optimisation studies

    International Nuclear Information System (INIS)

    Almen, A.J.

    1995-09-01

    A method for estimating mean absorbed dose to different organs and tissues was developed for paediatric patients undergoing X-ray investigations. The absorbed dose distribution in water was measured for the specific X-ray beam used. Clinical images were studied to determine X-ray beam positions and field sizes. Size and position of organs in the patient were estimated using ORNL phantoms and complementary clinical information. Conversion factors between the mean absorbed dose to various organs and entrance surface dose for five different body sizes were calculated. Direct measurements on patients estimating entrance surface dose and energy imparted for common X-ray investigations were performed. The examination technique for a number of paediatric X-ray investigations used in 19 Swedish hospitals was studied. For a simulated pelvis investigation of a 1-year old child the entrance surface dose was measured and image quality was estimated using a contrast-detail phantom. Mean absorbed doses to organs and tissues in urography, lung, pelvis, thoracic spine, lumbar spine and scoliosis investigations was calculated. Calculations of effective dose were supplemented with risk calculations for special organs e g the female breast. The work shows that the examination technique in paediatric radiology is not yet optimised, and that the non-optimised procedures contribute to a considerable variation in radiation dose. In order to optimise paediatric radiology there is a need for more standardised methods in patient dosimetry. It is especially important to relate measured quantities to the size of the patient, using e g the patient weight and length. 91 refs, 17 figs, 8 tabs

  3. [Clinical effectiveness of different doses of caffeine for primary apnea in preterm infants].

    Science.gov (United States)

    Zhao, Ying; Tian, Xiuying; Liu, Ge

    2016-01-01

    To evaluate the effectiveness and safety of different doses of caffeine in treatment of primary apnea in preterm infants. A total of 164 preterm infants (apnea, were recruited in Tianjin Central Hospital of Gynecology and Obstetrics from October 2013 to December 2014. The patients were prospectively allocated into low-dose (loading 20 mg/kg and maintenance of 5 mg/(kg·d) after 24 h, n=82) and high-dose (loading 20 mg/kg and maintenance of 15 mg/(kg·d) after 24 h, n=82) groups of caffeine citrate treatment by using a random number table. The treatment effects, side effects of caffeine, and the clinical outcome of the preterm infants were compared between groups by χ(2) test or nonparametric test. The patients in low-dose group had birth weight of (1,237 ± 338) g, male gender of 43 (52%) and gestational age of (29.8 ± 3.4) weeks. The patients in high-dose group had birth weight of (1 262 ± 296) g, male gender of 45 (55%) and gestational age of (29.9 ± 2.7) weeks. The baseline characteristics including birth weight, gender and gestational age were comparable between the two groups. Frequency of apnea was significantly lower in high-dose group compared with low-dose group (10 (8, 15) vs.18 (13, 22), Z = -2.610, P = 0.009), and the success rate of removal of the ventilator was significantly higher in high-dose group compared with low-dose group (85% (70/82) vs.70% (57/82), χ(2) = 5.898, P = 0.015). The effective rate of caffeine treatment was significantly higher in high-dose group compared with low-dose group (82% (67/82) vs.61% (50/82), χ(2)=8.619, P = 0.003). No significant differences were observed concerning the incidence of caffeine-associated side effects including tachycardia, irritability, difficulty in feeding, hyperglycemia, hypertension, digestive disorders and electrolyte disturbances between two groups (P all > 0.05). There were no significant differences in the clinical outcomes of the preterm infants including death during hospitalization

  4. Clinical characteristics of low dose radiation influences consequences on body . Chapter 7

    International Nuclear Information System (INIS)

    2000-01-01

    120 Chernobyl accident liquidators in age from 20 to 46 years were treated. During examination of sufferers from action of low radiation doses the polymorphism of complains and clinical manifestations are marked. Leading dysfunctions were astheno-vegetative dysfunctions. According with careful analysis of complains, existing clinical pattern and results of conducting investigations the four variants (syndromes) of disease's manifestation were revealed. Frequency of main clinical syndromes revealings with sicks having late actions of low radiation doses is defined. During comparing of disease pattern with got doses the certain dependence of frequency and seriousness of syndromes from got radiation doses are established. Sicks with consequences of radiation actions with rate 0.01-0.25 Gy have most typical astheno-neurotic syndrome. Under action of radiation with dose 0.25-0.5 Gy in late period the syndrome of vegetative dystonia is observed with liquidators. 25 men (20.9 %) sicks had hypothalamus syndrome of vegetative-muscular form. Most seldom 9.1 % of liquidators have syndrome of vegetative-sensor polyradiculoneuropathy

  5. The clinic and pathologic picture in the lethal dose irradiated ewes

    International Nuclear Information System (INIS)

    Halagan, J.; Stanikova, A.; Maracek, I.

    2004-01-01

    The history of clinical symptoms as well as pathologic histological and morphological changes after long/lasting gamma irradiation were estimated in seven clinical healthy ewes. The animals were irradiated continually seven days with totally 6.7 Gy per ewe. Clinically recognizable symptoms of the radiation sickness were observed commencing the 4 th after last dose of irradiation. Sharp increase of the body temperature, heart and respiratory frequency rate as well as apathy, anorexia, arrhythmia, dyspnoe, diarrhea, dehydration, polyuria were prevalent in clinical founding . All of the animals were death in course of seven days after last irradiated dose. The gastrointestinal radiation syndrome was typical evidence of gastrointestinal tract and the general hemorrhagic enhancing of the gamma irradiation damage effects was confirmed. (authors)

  6. Central image archiving and managements system for multicenter clinical studies: Lessons from low-dose CT for appendicitis trial

    Energy Technology Data Exchange (ETDEWEB)

    Ko, You Sun; Lee, Kyong Joon; Lee, Kyoung Ho [Dept. of Radiology, Seoul National University Bundang Hospital, Seongnam (Korea, Republic of); and others

    2017-03-15

    This special report aimed to document our experiences in implementing the Central Imaging Archiving and Management System (CIAMS) for a multicenter clinical trial, Low-dose CT for Appendicitis Trial (LOCAT), supported by the Korean Society of Radiology and Radiology Imaging Network of Korea for Clinical Research. LOCAT was a randomized controlled trial to determine whether low-dose CT is non-inferior to standard-dose CT with respect to the negative appendectomy rate in patients aged from 15 to 44 years. Site investigators downloaded the CT images from the site picture archiving and communication system servers, and uploaded the anonymized images to the primary server. CIAMS administrators inspected the images routed to the secondary server by a cross-check against image submission worksheets provided by the site investigators. The secondary server was automatically synchronized to the tertiary backup server. Up to June 2016, 2715 patients from 20 sites participated in LOCAT for 30 months. A total of 2539 patients' images (93.5%, 2539/2715) were uploaded to the primary server, 2193 patients' worksheets (80.8%, 2193/2715) were submitted, and 2163 patients' data (79.7%, 2163/2715) were finally monitored. No data error occurred.

  7. Dose accuracy of SoloSTAR and FlexPen as assessed in a clinical setting.

    Science.gov (United States)

    Friedrichs, Arnd

    2009-09-01

    This study aimed to compare the accuracy of SoloSTAR(sanofi-aventis, Paris, France) and FlexPen (Novo Nordisk, Bagsvaerd, Denmark) to deliver doses of insulin when used by insulin/device-naive people attending a local healthcare practice. For the determination of dose accuracy, SoloSTAR containing insulin glargine (lot 672) and FlexPen containing insulin aspart (lot SH70557) were used for all tests. The participants were given instruction by an independent monitor on how to use the pens. To be consistent, users were trained to hold the pens in situ for 10 s at the end of injection to ensure that the full dose was injected. Forty-eight subjects performed three dose deliveries of 20 units (into a sponge) with each pen type. The method of injecting into a sponge aimed to mimic real-life practice; this approach is commonly used to ensure the patient has a correct injection technique before the patient self-administers the injection. The delivery (n = 144) of individual doses of 20 units was not statistically different (P = 0.187) between SoloSTAR (mean +/- SD, 19.75 +/- 0.30 units) and FlexPen (19.80 +/- 0.33 units). In total, 2% of doses from both devices were insulin. This is likely to have beneficial clinical effects in terms of glycemic control, as well as improved patient confidence that insulin pens accurately deliver doses of insulin.

  8. Adaptive dose-finding studies: a review of model-guided phase I clinical trials.

    Science.gov (United States)

    Iasonos, Alexia; O'Quigley, John

    2014-08-10

    We provide a comprehensive review of adaptive phase I clinical trials in oncology that used a statistical model to guide dose escalation to identify the maximum-tolerated dose (MTD). We describe the clinical setting, practical implications, and safety of such applications, with the aim of understanding how these designs work in practice. We identified 53 phase I trials published between January 2003 and September 2013 that used the continual reassessment method (CRM), CRM using escalation with overdose control, or time-to-event CRM for late-onset toxicities. Study characteristics, design parameters, dose-limiting toxicity (DLT) definition, DLT rate, patient-dose allocation, overdose, underdose, sample size, and trial duration were abstracted from each study. In addition, we examined all studies in terms of safety, and we outlined the reasons why escalations occur and under what circumstances. On average, trials accrued 25 to 35 patients over a 2-year period and tested five dose levels. The average DLT rate was 18%, which is lower than in previous reports, whereas all levels above the MTD had an average DLT rate of 36%. On average, 39% of patients were treated at the MTD, and 74% were treated at either the MTD or an adjacent level (one level above or below). This review of completed phase I studies confirms the safety and generalizability of model-guided, adaptive dose-escalation designs, and it provides an approach for using, interpreting, and understanding such designs to guide dose escalation in phase I trials. © 2014 by American Society of Clinical Oncology.

  9. Toward an ozone standard to protect vegetation based on effective dose: a review of deposition resistances and a possible metric

    Science.gov (United States)

    Massman, W. J.

    Present air quality standards to protect vegetation from ozone are based on measured concentrations (i.e., exposure) rather than on plant uptake rates (or dose). Some familiar cumulative exposure-based indices include SUM06, AOT40, and W126. However, plant injury is more closely related to dose, or more appropriately to effective dose, than to exposure. This study develops and applies a simple model for estimating effective ozone dose that combines the plant canopy's rate of stomatal ozone uptake with the plant's defense to ozone uptake. Here the plant defense is explicitly parameterized as a function of gross photosynthesis and the model is applied using eddy covariance (ozone and CO 2) flux data obtained at a vineyard site in the San Joaquin Valley during the California Ozone Deposition Experiment (CODE91). With the ultimate intention of applying these concepts using prognostic models and remotely sensed data, the pathways for ozone deposition are parameterized (as much as possible) in terms of canopy LAI and the surface friction velocity. Results indicate that (1) the daily maximum potential for plant injury (based on effective dose) tends to coincide with the daily peak in ozone mixing ratio (ppbV), (2) potentially there are some significant differences between ozone metrics based on dose (no plant defense) and effective dose, and (3) nocturnal conductance can contribute significantly to the potential for plant ozone injury.

  10. Effect of low doses of cosyntropin on serum cortisol concentrations in clinically normal dogs.

    Science.gov (United States)

    Martin, Linda G; Behrend, Ellen N; Mealey, Katrina L; Carpenter, D Mark; Hickey, Kathy C

    2007-05-01

    To determine the lowest of 5 doses of cosyntropin (1.0, 0.5, 0.1, 0.05, or 0.01 microg/kg) administered IV that stimulates maximal cortisol secretion in clinically normal dogs. 10 clinically normal dogs. 5 dose-response experiments were performed in each of the dogs. Each dog received 5 doses of cosyntropin (1.0, 0.5, 0.1, 0.05, and 0.01 microg/kg) IV in random order (2-week interval between each dose). Serum samples for determination of cortisol concentrations were obtained before (baseline) and at 10, 20, 30, 40, 50, 60, 120, and 240 minutes after cosyntropin administration. Compared with baseline values, mean serum cortisol concentration in the study dogs increased significantly after administration of each of the 5 cosyntropin doses. Mean peak serum cortisol concentration was significantly lower after administration of 0.01, 0.05, and 0.1 microg of cosyntropin/kg, compared with findings after administration of 0.5 and 1.0 microg of cosyntropin/kg. After administration of 0.5 and 1.0 microg of cosyntropin/kg, mean peak serum cortisol concentration did not differ significantly; higher doses of cosyntropin resulted in more sustained increases in serum cortisol concentration, and peak response developed after a longer interval. Administration of cosyntropin IV at a dose of 0.5 microg/kg induced maximal cortisol secretion in healthy dogs. Serum cortisol concentration was reliably increased in all dogs after the administration of each of the 5 doses of cosyntropin. These data should be useful in subsequent studies to evaluate the hypothalamic-pituitary-adrenal axis in healthy and critically ill dogs.

  11. Comparison of photon organ and effective dose coefficients for PIMAL stylized phantom in bent positions in standard irradiation geometries.

    Science.gov (United States)

    Dewji, Shaheen; Reed, K Lisa; Hiller, Mauritius

    2017-08-01

    Computational phantoms with articulated arms and legs have been constructed to enable the estimation of radiation dose in different postures. Through a graphical user interface, the Phantom wIth Moving Arms and Legs (PIMAL) version 4.1.0 software can be employed to articulate the posture of a phantom and generate a corresponding input deck for the Monte Carlo N-Particle (MCNP) radiation transport code. In this work, photon fluence-to-dose coefficients were computed using PIMAL to compare organ and effective doses for a stylized phantom in the standard upright position with those for phantoms in realistic work postures. The articulated phantoms represent working positions including fully and half bent torsos with extended arms for both the male and female reference adults. Dose coefficients are compared for both the upright and bent positions across monoenergetic photon energies: 0.05, 0.1, 0.5, 1.0, and 5.0 MeV. Additionally, the organ doses are compared across the International Commission on Radiological Protection's standard external radiation exposure geometries: antero-posterior, postero-anterior, left and right lateral, and isotropic (AP, PA, LLAT, RLAT, and ISO). For the AP and PA irradiation geometries, differences in organ doses compared to the upright phantom become more profound with increasing bending angles and have doses largely overestimated for all organs except the brain in AP and bladder in PA. In LLAT and RLAT irradiation geometries, energy deposition for organs is more likely to be underestimated compared to the upright phantom, with no overall change despite increased bending angle. The ISO source geometry did not cause a significant difference in absorbed organ dose between the different phantoms, regardless of position. Organ and effective fluence-to-dose coefficients are tabulated. In the AP geometry, the effective dose at the 45° bent position is overestimated compared to the upright phantom below 1 MeV by as much as 27% and 82% in the 90

  12. Comparison of photon organ and effective dose coefficients for PIMAL stylized phantom in bent positions in standard irradiation geometries

    Energy Technology Data Exchange (ETDEWEB)

    Dewji, Shaheen; Hiller, Mauritius [Oak Ridge National Laboratory, Center for Radiation Protection Knowledge, Environmental Sciences Division, Oak Ridge, TN (United States); Reed, K.L. [Georgia Institute of Technology, Nuclear and Radiological Engineering Program, Atlanta, GA (United States)

    2017-08-15

    Computational phantoms with articulated arms and legs have been constructed to enable the estimation of radiation dose in different postures. Through a graphical user interface, the Phantom wIth Moving Arms and Legs (PIMAL) version 4.1.0 software can be employed to articulate the posture of a phantom and generate a corresponding input deck for the Monte Carlo N-Particle (MCNP) radiation transport code. In this work, photon fluence-to-dose coefficients were computed using PIMAL to compare organ and effective doses for a stylized phantom in the standard upright position with those for phantoms in realistic work postures. The articulated phantoms represent working positions including fully and half bent torsos with extended arms for both the male and female reference adults. Dose coefficients are compared for both the upright and bent positions across monoenergetic photon energies: 0.05, 0.1, 0.5, 1.0, and 5.0 MeV. Additionally, the organ doses are compared across the International Commission on Radiological Protection's standard external radiation exposure geometries: antero-posterior, postero-anterior, left and right lateral, and isotropic (AP, PA, LLAT, RLAT, and ISO). For the AP and PA irradiation geometries, differences in organ doses compared to the upright phantom become more profound with increasing bending angles and have doses largely overestimated for all organs except the brain in AP and bladder in PA. In LLAT and RLAT irradiation geometries, energy deposition for organs is more likely to be underestimated compared to the upright phantom, with no overall change despite increased bending angle. The ISO source geometry did not cause a significant difference in absorbed organ dose between the different phantoms, regardless of position. Organ and effective fluence-to-dose coefficients are tabulated. In the AP geometry, the effective dose at the 45 bent position is overestimated compared to the upright phantom below 1 MeV by as much as 27% and 82% in the

  13. Photon iso-effective dose for cancer treatment with mixed field radiation based on dose-response assessment from human and an animal model: clinical application to boron neutron capture therapy for head and neck cancer

    Science.gov (United States)

    González, S. J.; Pozzi, E. C. C.; Monti Hughes, A.; Provenzano, L.; Koivunoro, H.; Carando, D. G.; Thorp, S. I.; Casal, M. R.; Bortolussi, S.; Trivillin, V. A.; Garabalino, M. A.; Curotto, P.; Heber, E. M.; Santa Cruz, G. A.; Kankaanranta, L.; Joensuu, H.; Schwint, A. E.

    2017-10-01

    Boron neutron capture therapy (BNCT) is a treatment modality that combines different radiation qualities. Since the severity of biological damage following irradiation depends on the radiation type, a quantity different from absorbed dose is required to explain the effects observed in the clinical BNCT in terms of outcome compared with conventional photon radiation therapy. A new approach for calculating photon iso-effective doses in BNCT was introduced previously. The present work extends this model to include information from dose-response assessments in animal models and humans. Parameters of the model were determined for tumour and precancerous tissue using dose-response curves obtained from BNCT and photon studies performed in the hamster cheek pouch in vivo models of oral cancer and/or pre-cancer, and from head and neck cancer radiotherapy data with photons. To this end, suitable expressions of the dose-limiting Normal Tissue Complication and Tumour Control Probabilities for the reference radiation and for the mixed field BNCT radiation were developed. Pearson’s correlation coefficients and p-values showed that TCP and NTCP models agreed with experimental data (with r  >  0.87 and p-values  >0.57). The photon iso-effective dose model was applied retrospectively to evaluate the dosimetry in tumours and mucosa for head and neck cancer patients treated with BNCT in Finland. Photon iso-effective doses in tumour were lower than those obtained with the standard RBE-weighted model (between 10% to 45%). The results also suggested that the probabilities of tumour control derived from photon iso-effective doses are more adequate to explain the clinical responses than those obtained with the RBE-weighted values. The dosimetry in the mucosa revealed that the photon iso-effective doses were about 30% to 50% higher than the corresponding RBE-weighted values. While the RBE-weighted doses are unable to predict mucosa toxicity, predictions based on the proposed

  14. Differences in HCV viral decline between low and standard-dose pegylated-interferon-alpha-2a with ribavirin in HIV/HCV genotype 3 patients.

    Directory of Open Access Journals (Sweden)

    Antonio Rivero-Juárez

    Full Text Available BACKGROUND: The aim of the study was to analyze the different impact of standard and low-dose Peg-IFN-α2a/RBV therapies on HCV viral decline in HIV/HCV genotype 3 co-infected patients during the first weeks of treatment. METHODS: Plasma HCV viral decline was analyzed between baseline and weeks 1, 2 and 4 in two groups of treatment-naïve HCV genotype 3 patients with HIV co-infection. The Standard Dose Group (SDG included patients who received Peg-IFN at 180 µg/per week with a weight-adjusted dose of ribavirin; Low-Dose Group (LDG patients received Peg-IFN at 135 µg/per week with 800 mg/day ribavirin. The effect of IL28B genotype on HCV viral decline was evaluated in both groups. HCV viral decline was analyzed using a multivariate linear regression model. RESULTS: One hundred and six patients were included: 48 patients in the SDG and 58 in the LDG. HCV viral decline for patients in the LDG was less than for those in the SDG (week 1:1.72±0.74 log(10 IU/mL versus 1.78±0.67 log(10 IU/mL, p = 0.827; week 2:2.3±0.89 log(10 IU/mL versus 3.01±1.02 log(10 IU/mL, p = 0.013; week 4:3.52±1.2 log(10 IU/mL versus 4.09±1.1 log(10 IU/mL, p = 0.005. The linear regression model identified the Peg-IFN/RBV dose as an independent factor for HCV viral decline at week 4. CONCLUSIONS: Our results showed that HCV viral decline was less for patients in the low-dose group compared to those receiving the standard dose. Until a randomized clinical trial is conducted, clinicians should be cautious about using lower doses of Peg-IFN/RBV in HIV/HCV genotype 3 co-infected patients.

  15. Per-beam, planar IMRT QA passing rates do not predict clinically relevant patient dose errors

    Energy Technology Data Exchange (ETDEWEB)

    Nelms, Benjamin E.; Zhen Heming; Tome, Wolfgang A. [Canis Lupus LLC and Department of Human Oncology, University of Wisconsin, Merrimac, Wisconsin 53561 (United States); Department of Medical Physics, University of Wisconsin, Madison, Wisconsin 53705 (United States); Departments of Human Oncology, Medical Physics, and Biomedical Engineering, University of Wisconsin, Madison, Wisconsin 53792 (United States)

    2011-02-15

    Purpose: The purpose of this work is to determine the statistical correlation between per-beam, planar IMRT QA passing rates and several clinically relevant, anatomy-based dose errors for per-patient IMRT QA. The intent is to assess the predictive power of a common conventional IMRT QA performance metric, the Gamma passing rate per beam. Methods: Ninety-six unique data sets were created by inducing four types of dose errors in 24 clinical head and neck IMRT plans, each planned with 6 MV Varian 120-leaf MLC linear accelerators using a commercial treatment planning system and step-and-shoot delivery. The error-free beams/plans were used as ''simulated measurements'' (for generating the IMRT QA dose planes and the anatomy dose metrics) to compare to the corresponding data calculated by the error-induced plans. The degree of the induced errors was tuned to mimic IMRT QA passing rates that are commonly achieved using conventional methods. Results: Analysis of clinical metrics (parotid mean doses, spinal cord max and D1cc, CTV D95, and larynx mean) vs IMRT QA Gamma analysis (3%/3 mm, 2/2, 1/1) showed that in all cases, there were only weak to moderate correlations (range of Pearson's r-values: -0.295 to 0.653). Moreover, the moderate correlations actually had positive Pearson's r-values (i.e., clinically relevant metric differences increased with increasing IMRT QA passing rate), indicating that some of the largest anatomy-based dose differences occurred in the cases of high IMRT QA passing rates, which may be called ''false negatives.'' The results also show numerous instances of false positives or cases where low IMRT QA passing rates do not imply large errors in anatomy dose metrics. In none of the cases was there correlation consistent with high predictive power of planar IMRT passing rates, i.e., in none of the cases did high IMRT QA Gamma passing rates predict low errors in anatomy dose metrics or vice versa

  16. Guidelines for Standard Photography in Gross and Clinical Anatomy

    Science.gov (United States)

    Barut, Cagatay; Ertilav, Hakan

    2011-01-01

    Photography has a widespread usage in medicine and anatomy. In this review, authors focused on the usage of photography in gross and clinical anatomy. Photography in gross and clinical anatomy is not only essential for accurate documentation of morphological findings but also important in sharing knowledge and experience. Photographs of cadavers…

  17. Population pharmacokinetics of piperacillin in the early phase of septic shock – does standard dosing result in therapeutic plasma concentrations?

    DEFF Research Database (Denmark)

    Öbrink-Hansen, Kristina Margareta; Juul, Rasmus Vestergaard; Storgaard, Merete

    2015-01-01

    of administration. Time above the minimal inhibitory concentration (T>MIC) predicted for each patient was evaluated against clinical breakpoint MIC for Pseudomonas aeruginosa (16 mg/L). Pharmacokinetic-pharmacodynamic (PK/PD) targets evaluated were 50% fT>4xMIC and 100% f T>MIC. A population PK model was developed...... between patients and were associated with levels of plasma creatinine. Patients with impaired renal function were more likely to achieve predefined PK/PD targets compared to patients with preserved or augmented renal function. Simulations of alternative dosing regimens showed that frequent intermittent...... bolus dosing as well as dosing by extended and continuous infusion increases the probability of attaining therapeutic plasma concentrations. For septic shock patients with preserved or augmented renal function, dose increment or prolonged infusion of the drug need to be considered....

  18. Lactose malabsorption diagnosed by 50-g dose is inferior to assess clinical intolerance and to predict response to milk withdrawal than 25-g dose in an endemic area.

    Science.gov (United States)

    Ghoshal, Uday C; Kumar, Sunil; Misra, Asha; Mittal, Balraj

    2013-09-01

    Lactose malabsorption (LM), diagnosed currently using lactose hydrogen breath and tolerance tests (LHBT, LTT) with a high, nonphysiological dose (50-g), may mimic irritable bowel syndrome (IBS). In LM-endemic areas, clinically significant malabsorption (lactose intolerance) may be better diagnosed using a lesser dose, and positive results so obtained may predict response to milk withdrawal more effectively. Fifty patients each with IBS (Rome III) were evaluated using LHBT and LTT with 50-g, 25-g, and 12-g lactose. Sensitivity and specificity of LHBT and LTT with different dosages (gold standard: lactase gene C/T-13910 polymorphism) and symptom development were evaluated. Effect of milk withdrawal was studied. Of 150 patients, 37/50 (74%) and 28/50 (56%) had LM by LHBT and LTT using 50-g lactose; 41/50 (82%) and 31/50 (62%) had LM using 25-g lactose, and 14/50 (28%) and 29/50 (58%) using 12-g lactose, respectively. Sensitivity and specificity of LHBT using 50-g, 25-g, and 12-g lactose were 92.6%, 52.0%, and 94%, 60%, and 36.4%, 88.2%, and those of LTT, 92%, 80.0%, and 84.8%, 82.4%, and 66.7%, 58.8%, respectively. Breath hydrogen correlated with lactose dose. Though patients developing symptoms with 50-g lactose exhaled more hydrogen than those remaining asymptomatic, hydrogen levels did not differ following 25-g and 12-g dosages in relation to symptom development. Patients' milk intake was 335 ± 92 mL/d (≈ 16.7 ± 9.6-g lactose). Positive LHBT using 25-g dose better predicted symptom resolution than by 50-g and 12-g lactose. Twenty-five gram is the ideal dose of lactose for LHBT and LTT in LM-endemic areas. © 2013 Journal of Gastroenterology and Hepatology Foundation and Wiley Publishing Asia Pty Ltd.

  19. Low-dose (10-Gy) total skin electron beam therapy for cutaneous T-cell lymphoma: an open clinical study and pooled data analysis.

    Science.gov (United States)

    Kamstrup, Maria R; Gniadecki, Robert; Iversen, Lars; Skov, Lone; Petersen, Peter Meidahl; Loft, Annika; Specht, Lena

    2015-05-01

    Cutaneous T-cell lymphomas (CTCLs) are dominated by mycosis fungoides (MF) and Sézary syndrome (SS), and durable disease control is a therapeutic challenge. Standard total skin electron beam therapy (TSEBT) is an effective skin-directed therapy, but the possibility of retreatments is limited to 2 to 3 courses in a lifetime due to skin toxicity. This study aimed to determine the clinical effect of low-dose TSEBT in patients with MF and SS. In an open clinical study, 21 patients with MF/SS stages IB to IV were treated with low-dose TSEBT over dose of 10 Gy in 10 fractions. Data from 10 of these patients were published previously but were included in the current pooled data analysis. Outcome measures were response rate, duration of response, and toxicity. The overall response rate was 95% with a complete cutaneous response or a very good partial response rate (dose (10-Gy) TSEBT offers a high overall response rate and is relatively safe. With this approach, reirradiation at times of relapse or progression is likely to be less toxic than standard dose TSEBT. It remains to be established whether adjuvant and combination treatments can prolong the beneficial effects of low-dose TSEBT. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. [Clinical gastroenterology--luxury or standard of service in gastroenterology?].

    Science.gov (United States)

    Birkner, B

    2005-12-01

    Gastroenterology is one of the important specialities in internal medicine. The reform of the training curriculum for internal medicine and the reimbursement for inpatient and outpatient services in gastroenterology threatens the existence of internal medicine and gastroenterology in Germany, too. The capacity for training in internal medicine and gastroenterology is reduced by a decrease in the number of hospital beds in academic and community training centres. The concentration on gastrointestinal endoscopy in outpatient gastroenterology will be a result of an increasing demand for gastrointestinal endoscopy services and the decreasing number of gastroenterology clinics, respectively. Therefore, clinical gastroenterology as a core service in gastroenterology will be steadily eliminated. This development will diminish clinical gastroenterology to gastrointestinal endoscopy by eliminating the clinical services for chronic gastroenterological conditions such as, e.g., IBD, chronic hepatitis, reflux disease, IBS and functional dyspepsia. In this way gastroenterology looses its central role in health care services in specialised internal medicine. In 2003 the American Gastroenterological Association position paper: "Training the Gastroenterologist of the Future: the Gastroenterology Core Curriculum" was published. It has emphasised the role of clinical gastroenterology in medical training and medical services, too. Clinical gastroenterology consists of an array of several disciplines, e.g., GI physiology, GI research, infectious diseases, hepatology, oncology and gastrointestinal endoscopy, which all contribute to the effectiveness and efficiency in health care service. Financial incentives and better prospects of leading positions for young gastroenterologists in clinical gastroenterology have to be accomplished in order to nourish clinical gastroenterology in Germany. The German Association of Gastroenterology should negotiate with the responsible authorities for

  1. Donepezil across the spectrum of Alzheimer's disease: dose optimization and clinical relevance.

    Science.gov (United States)

    Lee, J-H; Jeong, S-K; Kim, B C; Park, K W; Dash, A

    2015-05-01

    Alzheimer's disease (AD) is an irreversible and progressive neurodegenerative disorder. AD is the most common cause of dementia worldwide, and its incidence is increasing in line with population aging. The primary feature of AD is progressive cognitive decline, and severe AD is characterized by reduced communication skills and mobility. However, successful treatment can substantially improve quality of life. Donepezil is an acetylcholinesterase inhibitor approved for use across the full spectrum of mild, moderate, and severe AD. Donepezil has been available at doses of 5 or 10 mg once daily for more than a decade and, more recently, a single high once-daily sustained-release 23-mg dose has been approved for treatment of patients with moderate to severe AD. The rationale for the higher dose formulation was the expected increase in acetylcholinesterase inhibition given the dose-response relationship of donepezil, with the benefits of the higher dose being most apparent in patients with more advanced AD. Donepezil 5 and 10 mg/day have been well studied in mild-to-moderate AD, and a clinical trial has confirmed the benefits of donepezil 23 mg/day in patients with moderate to severe AD, particularly for language and visuospatial ability. This review presents an overview of the evidence for donepezil across the spectrum of AD, with a focus on dose optimization for disease progression. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  2. Radiation dose optimization in coronary angiography and percutaneous coronary intervention (PCI). II. Clinical evaluation

    International Nuclear Information System (INIS)

    Geijer, Haakan; Andersson, Torbjoern; Beckman, Karl-Wilhelm; Persliden, Jan

    2002-01-01

    In a previous part of this study, the fluoroscopy dose rate was reduced in a cardiac catheterization laboratory. The objectives of the present study were to evaluate the effects in a clinical population undergoing percutaneous coronary intervention (PCI) of the dose-reducing measures detailed previously. Kerma area-product (KAP) values were first recorded for 154 patients undergoing PCI. Then, the fluoroscopy KAP rate was reduced from 44 to 16 mGy cm 2 /s by increasing filtration and reducing the image intensifier dose request. After this optimization, KAP was recorded for another 138 PCI procedures. After adjustment for differing proportions of combined procedures (coronary angiography+PCI), the total KAP was reduced to 67% of the original value with a 95% confidence interval from 57 to 78%, statistically significant. The mean total KAP values were 93.6 Gy cm 2 before and 69.1 Gy cm 2 after optimization. The KAP for digital acquisition did not change significantly. It is possible to make a large dose reduction in PCI by reducing the fluoroscopy dose rate. This dose reduction is beneficial for both patients and staff. (orig.)

  3. Low-Dose versus Standard-Dose Intravenous Immunoglobulin to Prevent Fetal Intracranial Hemorrhage in Fetal and Neonatal Alloimmune Thrombocytopenia: A Randomized Trial.

    Science.gov (United States)

    Paridaans, Noortje P; Kamphuis, Marije M; Taune Wikman, Agneta; Tiblad, Eleonor; Van den Akker, Eline S; Lopriore, Enrico; Challis, Daniel; Westgren, Magnus; Oepkes, Dick

    2015-01-01

    Pregnancies at risk of fetal and neonatal alloimmune thrombocytopenia (FNAIT) are commonly treated using weekly intravenous immunoglobulin (IVIG) at 1 g/kg maternal weight. IVIG is an expensive multidonor human blood product with dose-related side effects. Our aim was to evaluate the effectiveness of IVIG at a lower dose, i.e., 0.5 g/kg. This was a randomized controlled multicenter trial conducted in Sweden, the Netherlands and Australia. Pregnant women with human platelet antigen alloantibodies and an affected previous child without intracranial hemorrhage (ICH) were enrolled. The participants were randomized to IVIG at 0.5 or 1 g/kg per week. The analyses were per intention to treat. The primary outcome was fetal or neonatal ICH. Secondary outcomes were platelet count at birth, maternal and neonatal IgG levels, neonatal treatment and bleeding other than ICH. A total of 23 women were randomized into two groups (low dose: n = 12; standard dose: n = 11). The trial was stopped early due to poor recruitment. No ICH occurred. The median newborn platelet count was 81 × 10(9)/l (range 8-269) in the 0.5 g/kg group versus 110 × 10(9)/l (range 11-279) in the 1 g/kg group (p = 0.644). The risk of adverse outcomes in FNAIT pregnancies treated with IVIG at 0.5 g/kg is very low, similar to that using 1 g/kg, although our uncompleted trial lacked the power to conclusively prove the noninferiority of using the low dose.

  4. Seventy kilovolt ultra-low dose CT of the paranasal sinus: first clinical results

    International Nuclear Information System (INIS)

    Bodelle, B.; Wichmann, J.L.; Klotz, N.; Lehnert, T.; Vogl, T.J.; Luboldt, W.; Schulz, B.

    2015-01-01

    Aim: To evaluate the diagnostic image quality and radiation dose of low-dose 70 kV computed tomography (CT) of the paranasal sinus in comparison to 100 and 120 kV CT. Materials and methods: CT of the paranasal sinus was performed in 127 patients divided into three groups using different tube voltages and currents (70 kV/75 mAs, ultra-low dose protocol, n = 44; 100 kV/40 mAs, standard low-dose protocol, n = 42; 120 kV/40 mAs, standard protocol, n = 41). CT dose index (CTDIvol), dose–length product (DLP), attenuation, image noise and signal-to-noise ratio (SNR) were compared between the groups using Wilcoxon–Mann–Whitney U-test. Subjective diagnostic image quality was compared by using a five-point scale (1 = non-diagnostic, 5 = excellent, read by two readers in consensus) and Cohen's weighted kappa analysis for interobserver agreement. Results: Radiation dose was significantly lower with 70 kV acquisition than 100 and 120 kV (DLP: 31 versus 52 versus 82 mGy·cm; CTDI 2.33 versus 3.95 versus 6.31 mGy, all p < 0.05). Mean SNR (70 kV: 0.37; 100 kV: 0.21; 120 kV: 0.13; p < 0.05) and organ attenuation increased significantly with lower voltages. All examinations showed diagnostic image quality. Subjective diagnostic image quality was higher with standard protocols than the 70 kV protocol (120 kV: 5.0; 100 kV: 4.5; 70 kV: 3.5, p < 0.05) without significant differences with substantial interobserver agreement (κ > 0.59). Conclusion: The ultra-low dose (70 kV) CT imaging of the paranasal sinus allowed for significant dose reduction by 61% and an increased attenuation of organ structures in comparison to standard acquisition while maintaining diagnostic image quality with a slight reduction in subjective image quality. -- Highlights: •Image quality and radiation dose of 70 kV ultra-low dose CT of the paranasal sinus. •70 kV ultra-low dose CT of the paranasal sinus allows for dose reduction by 61%. •70 kV CT of the

  5. Submillisievert standard-pitch CT pulmonary angiography with ultra-low dose contrast media administration: A comparison to standard CT imaging.

    Science.gov (United States)

    Suntharalingam, Saravanabavaan; Mikat, Christian; Stenzel, Elena; Erfanian, Youssef; Wetter, Axel; Schlosser, Thomas; Forsting, Michael; Nassenstein, Kai

    2017-01-01

    To evaluate the image quality and radiation dose of submillisievert standard-pitch CT pulmonary angiography (CTPA) with ultra-low dose contrast media administration in comparison to standard CTPA. Hundred patients (56 females, 44 males, mean age 69.6±15.4 years; median BMI: 26.6, IQR: 5.9) with suspected pulmonary embolism were examined with two different protocols (n = 50 each, group A: 80 kVp, ref. mAs 115, 25 ml of contrast medium; group B: 100 kVp, ref. mAs 150, 60 ml of contrast medium) using a dual-source CT equipped with automated exposure control. Objective and subjective image qualities, radiation exposure as well as the frequency of pulmonary embolism were evaluated. There was no significant difference in subjective image quality scores between two groups regarding pulmonary arteries (p = 0.776), whereby the interobserver agreement was excellent (group A: k = 0.9; group B k = 1.0). Objective image analysis revealed that signal intensities (SI), signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of the pulmonary arteries were equal or significantly higher in group B. There was no significant difference in the frequency of pulmonary embolism (p = 0.65). Using the low dose and low contrast media protocol resulted in a radiation dose reduction by 71.8% (2.4 vs. 0.7 mSv; pcontrast agent volume can obtain sufficient image quality to exclude or diagnose pulmonary emboli while reducing radiation dose by approximately 71%.

  6. Joint American Nuclear Society and Health Physics Society Conference: Applicability of Radiation Response Models to Low Dose Protection Standards.

    Science.gov (United States)

    Glines, Wayne M; Markham, Anna

    2018-05-01

    Seventy-five years after the Hanford Site was initially created as the primary plutonium production site for atomic weapons development under the Manhattan Project, the American Nuclear Society and the Health Physics Society are sponsoring a conference from 30 September through 3 October 2018, in Pasco, Washington, titled "Applicability of Radiation Response Models to Low Dose Protection Standards." The goal of this conference is to use current scientific data to update the approach to regulating low-level radiation doses; i.e., to answer a quintessential question of radiation protection-how to best develop radiation protection standards that protect human populations against detrimental effects while allowing the beneficial uses of radiation and radioactive materials. Previous conferences (e.g., "Wingspread Conference," "Arlie Conference") have attempted to address this question; but now, almost 20 y later, the key issues, goals, conclusions, and recommendations of those two conferences remain and are as relevant as they were then. Despite the best efforts of the conference participants and increased knowledge and understanding of the science underlying radiation effects in human populations, the bases of current radiation protection standards have evolved little. This 2018 conference seeks to provide a basis and path forward for evolving radiation protection standards to be more reflective of current knowledge and understanding of low dose response models.

  7. Reliability of individual doses relating to the epidemiological studies on nuclear industry workers in Japan (1). Historical changes on definition of radiation dose, historical changes on technical standards of measurement and radiation workplace

    International Nuclear Information System (INIS)

    Numakunai, Takao; Ishiguro, Hideharu; Kawada, Yasushi; Minami, Kentaro; Yoshimoto, Yasuhiko.

    1997-01-01

    Records of radiation workers collected in the Research Organization for Information of Science and Technology, concerning individual doses from 1957 to 1992 were used for epidemiological studies for obtaining the scientific information of the effect of low dose radiation. Since many changes were made on definition of radiation dose, dosimetry technology and so on during such a long time period, reliability of recorded individual doses and of their measurement should be evaluated for validation, which is the purpose of this paper. Followings were discussed and validation was made. Historical changes on standards for radiation protection: ICRP Recommendation and ICRU Report, and changes of law concerning radiation dose in Japan and of dose standards. Changes on dosimetry for radiation protection: ICRP Recommendation and working place dosimetry, trends of investigations for introduction of measured practical doses, ICRU sphere as a receptor, and introduction of measured practical doses. Characteristics of radiation field and radiation exposure: Radiation source and characteristics of radiation field; Research and development organizations for atomic power, atomic power plants, facilities for nuclear fuel, Classification of radiation works and characteristics of the exposure; BWR, PWR, GCR. Changes on the standards of individual dosemeter and on its use: method to use individual dosemeter and its installation, measurement of individual dose and Japanese Industrial Standard (JIS); Standard of the film badge for X and gamma rays, Standard of the film badge for neutron, Standard for thermoluminescence dosemeter, and changes on selection of the major apparatus and on its use. (K.H.)

  8. The clinical demand for information and the radiation dose in pelvimetry and amniography

    International Nuclear Information System (INIS)

    Wilbrand, H.F.; Lindmark, G.; Ytterbergh, C.

    1982-01-01

    Radiographic measurements are an important part of antenatal care and are in fact used to a great extent in nulliparous women. In view of this clinical background and also for ethical reasons, reduction of the radiation doses is mandatory. As radiographic pelvimetry is used in so many pregnant women, it is of importance that no higher radiation doses are applied than are absolutely needed to guarantee correct and necessary information. Dose reduction is afforded in two different ways - by optimizing the imaging techniques and by closing a suitable film-screen combination. Measurement of absorbed doses in patients was carried out with highly sensitive lithium fluoride thermoluminiscence dosimeters (TLD) with a dimension of 3x3x0.9 mm (Harshaw type TLD-100). All TLD probes were calibrated with Co60 radiation between the measurement series. Absorbed radiation doses were measured in the rectum for different film-screen combinations. Depending on the position of the fetus in relation to the maternal pelvis, it is obvious that in any individual case varying parts of the fetus will lie directly in the radiation beam. In amniography the absorbed radiation doses will vary from case to case depending on the number of exposures, which should not exceed six, and the duration of fluoroscopy, which should be no longer than 1 min. With the use of lanex Regular screens and highly coned images the radiation dose will not exceed 3.0 mGy. Since a high image quality is mandatory for evaluation of disorders in the fetal skeleton, measurements were not performed with other high-speed screens. The MR 800 screen appears to provide further reduction of the radiation dose in this type of examination. (orig./MG)

  9. SU-F-T-93: Breast Surface Dose Enhancement Using a Clinical Prone Breast Board

    Energy Technology Data Exchange (ETDEWEB)

    Guerra, M; Jozsef, G [New York University Langone Medical Center, New York, NY (United States)

    2016-06-15

    Purpose: The use of specialized patient set-up devices in radiotherapy, such as prone breast boards, may have unwanted dosimetric effects. The goal of this study was to evaluate the effect of a clinically used prone breast board on skin dose due to buildup. Methods: GafChromic film (EBT3) was used for dose measurements on the surface of a solid water phantom shaped to mimic the curvature of the breast. We investigated two setup scenarios: the medial field border placed at the medial edge of the board and 1 cm contralaterally from that edge. A strip of film was taped to the medial surface of the phantom. Gantry angles varied from 10 to 30 degrees below the lateral gantry position, representing anterior oblique fields. The measurements were performed with and without the presence of the board; the ratio of their corresponding doses (dose enhancement) was evaluated. Results: For the cases where the field edge is at the edge of the board, the dose enhancement is negligible for all the tested angles. When the field edge is 1 cm inside the board, the maximum surface dose enhancement varies depending on the gantry angle between 2.2 for 30 degrees and 3.2 for 20 degrees. The length on the film at which the presence of the board is detectable (i.e. where there is dose enhancement) is longer for the shallower angles. Conclusion: Even the low-density, thin carbon fiber board with a thin soft foam pad on the top can produce significant dose enhancement on the skin in prone breast treatment due to loss of buildup. However, it happens only when the patient mid-sternum is over the board, i.e. the medial edge of the field traverses through the board and pad. Even then, the effect occurs only at the field edge, i.e. the penumbral region.

  10. Role of renal function in risk assessment of target non-attainment after standard dosing of meropenem in critically ill patients: a prospective observational study.

    Science.gov (United States)

    Ehmann, Lisa; Zoller, Michael; Minichmayr, Iris K; Scharf, Christina; Maier, Barbara; Schmitt, Maximilian V; Hartung, Niklas; Huisinga, Wilhelm; Vogeser, Michael; Frey, Lorenz; Zander, Johannes; Kloft, Charlotte

    2017-10-21

    Severe bacterial infections remain a major challenge in intensive care units because of their high prevalence and mortality. Adequate antibiotic exposure has been associated with clinical success in critically ill patients. The objective of this study was to investigate the target attainment of standard meropenem dosing in a heterogeneous critically ill population, to quantify the impact of the full renal function spectrum on meropenem exposure and target attainment, and ultimately to translate the findings into a tool for practical application. A prospective observational single-centre study was performed with critically ill patients with severe infections receiving standard dosing of meropenem. Serial blood samples were drawn over 4 study days to determine meropenem serum concentrations. Renal function was assessed by creatinine clearance according to the Cockcroft and Gault equation (CLCR CG ). Variability in meropenem serum concentrations was quantified at the middle and end of each monitored dosing interval. The attainment of two pharmacokinetic/pharmacodynamic targets (100%T >MIC , 50%T >4×MIC ) was evaluated for minimum inhibitory concentration (MIC) values of 2 mg/L and 8 mg/L and standard meropenem dosing (1000 mg, 30-minute infusion, every 8 h). Furthermore, we assessed the impact of CLCR CG on meropenem concentrations and target attainment and developed a tool for risk assessment of target non-attainment. Large inter- and intra-patient variability in meropenem concentrations was observed in the critically ill population (n = 48). Attainment of the target 100%T >MIC was merely 48.4% and 20.6%, given MIC values of 2 mg/L and 8 mg/L, respectively, and similar for the target 50%T >4×MIC . A hyperbolic relationship between CLCR CG (25-255 ml/minute) and meropenem serum concentrations at the end of the dosing interval (C 8h ) was derived. For infections with pathogens of MIC 2 mg/L, mild renal impairment up to augmented renal function was

  11. The Cardiology Audit and Registration Data Standards (CARDS), European data standards for clinical cardiology practice

    NARCIS (Netherlands)

    M.R. Flynn (Rachel); C. Barrett (Conor); F.G. Cosio (Francisco); A.K. Gitt (Anselm); L.C. Wallentin (Lars); P. Kearney (Peter); M. Lonergan (Moira); E. Shelley (Emer); M.L. Simoons (Maarten)

    2005-01-01

    textabstractAIMS: Systematic registration of data from clinical practice is important for clinical care, local, national and international registries, and audit. Data to be collected for these different purposes should be harmonized. Therefore, during Ireland's Presidency of the European Union (EU)

  12. Impact of Clinical Response on Different Approved Doses in Japan and the United States.

    Science.gov (United States)

    Sugita, Yuko; Inoue, Eisuke; Narukawa, Mamoru

    2012-10-01

    The pharmaceutical industry has increasingly aimed to achieve efficient strategies for simultaneous international and worldwide development of medicines, and there has been a growing need to understand ethnic differences in drug evaluation. Japan is one of the unique countries in which substantial domestic clinical data are required for dose selection as well as for marketing authorization. However, it appears challenging to accumulate a large amount of data in a single country in the recent shift to international drug development. To gain a better understanding of the influence of ethnic factors, the dosages of the products approved in Japan during 2003-2010 were reviewed, and differences in clinical responses between Japan and the United States were evaluated using a modeling approach. Of new medicines (new molecular entities) approved in Japan, 39 products (28.1%) have been approved at a different dose level compared with the United States, of which 13 products have considerable difference, twice or greater. Of those 13 products, only 2 were suggested to have a different clinical response, although limited data availability should be taken into careful consideration. Further investigation is recommended to establish new approaches for appropriate dose selection and thereby increase the efficiency of international drug development. 2012 American College of Clinical Pharmacology.

  13. Impact of genetic and clinical factors on dose requirements and quality of anticoagulation therapy in Polish patients receiving acenocoumarol: dosing calculation algorithm.

    Science.gov (United States)

    Wolkanin-Bartnik, Jolanta; Pogorzelska, Hanna; Szperl, Małgorzata; Bartnik, Aleksandra; Koziarek, Jacek; Bilinska, Zofia T

    2013-11-01

    Despite the recent emergence of new oral anticoagulants, vitamin K antagonists remain the primary therapy in patients with atrial fibrillation and the only therapy licensed for use in patients with artificial heart valves. The aim of this study was (a) to assess the impact of clinical and genetic factors on acenocoumarol (AC) dose requirements and the percentage of time in therapeutic range (%TTR) and (b) to develop pharmacogenetic-guided AC dose calculation algorithm. We included 235 outpatients of the Institute of Cardiology (Warsaw), mean age 69.3, 46.9% women, receiving AC for artificial heart valves and/or atrial fibrillation. A multiple linear-regression analysis was performed using log-transformed effective AC dose as the dependent variable, and combining CYP2C9 and VKORC1 genotyping with other clinical factors as independent predictors. We identified factors that influenced the AC dose: CYP2C9 polymorphisms (P=0.004), VKORC1 polymorphisms (Pgenetic factors explained 49.0% of AC dose variability. We developed a dosing calculation algorithm that is, to the best of our knowledge, the first one to assess the effect of such clinical factors as creatinine clearance and dietary vitamin K intake on the AC dose. The clinical usefulness of the algorithm was assessed on separate validation group (n=50) with 70% accuracy. Dietary vitamin K intake higher than 200 mcg/day improved international normalized ratio control (%TTR 73.3±17 vs. 67.7±18, respectively, P=0.04). Inclusion of a variety of genetic and clinical factors in the dosing calculation algorithm allows for precise AC dose estimation in most patients and thus improves the efficacy and safety of the therapy.

  14. Comparison of standard versus double dose of amoxicillin in the treatment of non‐severe pneumonia in children aged 2–59 months: a multi‐centre, double blind, randomised controlled trial in Pakistan

    Science.gov (United States)

    Hazir, Tabish; Qazi, Shamim A; Nisar, Yasir Bin; Maqbool, Sajid; Asghar, Rai; Iqbal, Imran; Khalid, Sobia; Randhawa, Sajid; Aslam, Shazia; Riaz, Sobia; Abbasi, Saleem

    2007-01-01

    Introduction WHO pneumonia case management guidelines recommend oral amoxicillin as first line treatment for non‐severe pneumonia. Increasing treatment failure rates have been reported over a period of time, which could possibly be due to increasing minimum inhibitory concentrations of Streptococcus pneumoniae and Haemophilus influenzae for amoxicillin. Microbiological data show that this resistance can be overcome by increasing amoxicillin dosage. Based on this data, we examined whether we can improve the clinical outcome in non‐severe pneumonia by doubling the dose of amoxicillin. Methods A double blind randomised controlled trial was conducted in the outpatient departments of four large hospitals in Pakistan. Children aged 2–59 months with non‐severe pneumonia were randomised to receive either standard (45 mg/kg/day) or double dose (90 mg/kg/day) oral amoxicillin for 3 days and then followed up for 14 days. Final outcome was treatment failure by day 5. Results From September 2003 to June 2004, 876 children completed the study. 437 were randomised to standard and 439 to double dose oral amoxicillin. 20 (4.5%) children in the standard and 25 (5.7%) in the double dose group had therapy failure by day 5. Including the relapses, by day 14 there were 26 (5.9%) cumulative therapy failures with standard and 35 (7.9%) with double dose amoxicillin. These differences were not statistically significant (p = 0.55 and p = 0.29, respectively). Conclusion Clinical outcome in children aged 2–59 months with non‐severe pneumonia is the same with standard and double dose oral amoxicillin. Non‐severe pneumonia can be treated effectively and safely with a 3 day course of a standard dose. PMID:16547082

  15. Maximal standard dose of parenteral iron for hemodialysis patients: an MRI-based decision tree learning analysis.

    Directory of Open Access Journals (Sweden)

    Guy Rostoker

    Full Text Available Iron overload used to be considered rare among hemodialysis patients after the advent of erythropoesis-stimulating agents, but recent MRI studies have challenged this view. The aim of this study, based on decision-tree learning and on MRI determination of hepatic iron content, was to identify a noxious pattern of parenteral iron administration in hemodialysis patients.We performed a prospective cross-sectional study from 31 January 2005 to 31 August 2013 in the dialysis centre of a French community-based private hospital. A cohort of 199 fit hemodialysis patients free of overt inflammation and malnutrition were treated for anemia with parenteral iron-sucrose and an erythropoesis-stimulating agent (darbepoetin, in keeping with current clinical guidelines. Patients had blinded measurements of hepatic iron stores by means of T1 and T2* contrast MRI, without gadolinium, together with CHi-squared Automatic Interaction Detection (CHAID analysis.The CHAID algorithm first split the patients according to their monthly infused iron dose, with a single cutoff of 250 mg/month. In the node comprising the 88 hemodialysis patients who received more than 250 mg/month of IV iron, 78 patients had iron overload on MRI (88.6%, 95% CI: 80% to 93%. The odds ratio for hepatic iron overload on MRI was 3.9 (95% CI: 1.81 to 8.4 with >250 mg/month of IV iron as compared to <250 mg/month. Age, gender (female sex and the hepcidin level also influenced liver iron content on MRI.The standard maximal amount of iron infused per month should be lowered to 250 mg in order to lessen the risk of dialysis iron overload and to allow safer use of parenteral iron products.

  16. Detection of pulmonary nodules at multirow-detector CT: effectiveness of double reading to improve sensitivity at standard-dose and low-dose chest CT

    International Nuclear Information System (INIS)

    Wormanns, Dag; Beyer, Florian; Heindel, Walter; Ludwig, Karl; Diederich, Stefan

    2005-01-01

    The purpose of this study was to assess the effectiveness of double reading to increase the sensitivity of lung nodule detection at standard-dose (SDCT) and low-dose multirow-detector CT (LDCT). SDCT (100 mAs effective tube current) and LDCT (20 mAs) of nine patients with pulmonary metastases were obtained within 5 min using four-row detector CT. Softcopy images reconstructed with 5-mm slice thickness were read by three radiologists independently. Images with 1.25-mm slice thickness served as the gold standard. Sensitivity was assessed for single readers and combinations. The effectiveness of double reading was expressed as the increase of sensitivity. Average sensitivity for detection of 390 nodules (size 3.9±3.2 mm) for single readers was 0.63 (SDCT) and 0.64 (LDCT). Double reading significantly increased sensitivity to 0.74 and 0.79, respectively. No significant difference between sensitivity at SDCT and LDCT was observed. The percentage of nodules detected by all three readers concordantly was 52% for SDCT and 47% for LDCT. Although double reading increased the detection rate of pulmonary nodules from 63% to 74-79%, a considerable proportion of nodules remained undetected. No difference between sensitivities at LDCT and SDCT for detection of small nodules was observed. (orig.)

  17. Main clinical, therapeutic and technical factors related to patient's maximum skin dose in interventional cardiology procedures

    Science.gov (United States)

    Journy, N; Sinno-Tellier, S; Maccia, C; Le Tertre, A; Pirard, P; Pagès, P; Eilstein, D; Donadieu, J; Bar, O

    2012-01-01

    Objective The study aimed to characterise the factors related to the X-ray dose delivered to the patient's skin during interventional cardiology procedures. Methods We studied 177 coronary angiographies (CAs) and/or percutaneous transluminal coronary angioplasties (PTCAs) carried out in a French clinic on the same radiography table. The clinical and therapeutic characteristics, and the technical parameters of the procedures, were collected. The dose area product (DAP) and the maximum skin dose (MSD) were measured by an ionisation chamber (Diamentor; Philips, Amsterdam, The Netherlands) and radiosensitive film (Gafchromic; International Specialty Products Advanced Materials Group, Wayne, NJ). Multivariate analyses were used to assess the effects of the factors of interest on dose. Results The mean MSD and DAP were respectively 389 mGy and 65 Gy cm−2 for CAs, and 916 mGy and 69 Gy cm−2 for PTCAs. For 8% of the procedures, the MSD exceeded 2 Gy. Although a linear relationship between the MSD and the DAP was observed for CAs (r=0.93), a simple extrapolation of such a model to PTCAs would lead to an inadequate assessment of the risk, especially for the highest dose values. For PTCAs, the body mass index, the therapeutic complexity, the fluoroscopy time and the number of cine frames were independent explanatory factors of the MSD, whoever the practitioner was. Moreover, the effect of technical factors such as collimation, cinematography settings and X-ray tube orientations on the DAP was shown. Conclusion Optimising the technical options for interventional procedures and training staff on radiation protection might notably reduce the dose and ultimately avoid patient skin lesions. PMID:22457404

  18. The first clinical implementation of real-time image-guided adaptive radiotherapy using a standard linear accelerator.

    Science.gov (United States)

    Keall, Paul J; Nguyen, Doan Trang; O'Brien, Ricky; Caillet, Vincent; Hewson, Emily; Poulsen, Per Rugaard; Bromley, Regina; Bell, Linda; Eade, Thomas; Kneebone, Andrew; Martin, Jarad; Booth, Jeremy T

    2018-02-07

    Until now, real-time image guided adaptive radiation therapy (IGART) has been the domain of dedicated cancer radiotherapy systems. The purpose of this study was to clinically implement and investigate real-time IGART using a standard linear accelerator. We developed and implemented two real-time technologies for standard linear accelerators: (1) Kilovoltage Intrafraction Monitoring (KIM) that finds the target and (2) multileaf collimator (MLC) tracking that aligns the radiation beam to the target. Eight prostate SABR patients were treated with this real-time IGART technology. The feasibility, geometric accuracy and the dosimetric fidelity were measured. Thirty-nine out of forty fractions with real-time IGART were successful (95% confidence interval 87-100%). The geometric accuracy of the KIM system was -0.1 ± 0.4, 0.2 ± 0.2 and -0.1 ± 0.6 mm in the LR, SI and AP directions, respectively. The dose reconstruction showed that real-time IGART more closely reproduced the planned dose than that without IGART. For the largest motion fraction, with real-time IGART 100% of the CTV received the prescribed dose; without real-time IGART only 95% of the CTV would have received the prescribed dose. The clinical implementation of real-time image-guided adaptive radiotherapy on a standard linear accelerator using KIM and MLC tracking is feasible. This achievement paves the way for real-time IGART to be a mainstream treatment option. Copyright © 2018 Elsevier B.V. All rights reserved.

  19. Clinical Characteristics and Outcomes Associated With High-Dose Intravenous Thiamine Administration in Patients With Encephalopathy.

    Science.gov (United States)

    Nakamura, Zev M; Tatreau, Jason R; Rosenstein, Donald L; Park, Eliza M

    2018-01-11

    Wernicke encephalopathy is a common neuropsychiatric syndrome due to thiamine deficiency. There is no consensus regarding thiamine dosing when Wernicke encephalopathy is suspected. A longstanding dosing strategy for Wernicke encephalopathy is 100mg daily, yet updated clinical guidelines suggest using high-dose intravenous (HDIV) thiamine. To describe thiamine prescribing practices at a large, public academic hospital and investigate clinical characteristics and outcomes associated with HDIV thiamine in patients with encephalopathy who received IV thiamine. Electronic medical records of hospitalized patients who received thiamine between 4/4/2014 and 11/1/2015 were reviewed. Chi-square tests, Wilcoxon Rank Sum tests, and logistic regression were used to compare clinical variables in patients with encephalopathy who received HDIV thiamine (≥ 200mg twice daily) vs lower doses of IV thiamine. Among the total of 5236 thiamine orders, 29% (n = 1531) were IV; 10% (n = 150) of IV orders met HDIV criteria. In patients with encephalopathy who received IV thiamine (n = 432), HDIV thiamine was administered to 20% (n = 86) and only 2.1% (n = 9) received dosing consistent with Royal College of Physicians guidelines. In bivariable analyses, HDIV thiamine was associated with surgical services (p = 0.001), psychiatric consultation (p < 0.001), and decreased mortality (p = 0.004). In multivariable models, the association between HDIV thiamine and decreased in-hospital mortality did not meet statistical significance (p = 0.061). In a large, public academic hospital, guideline-concordant thiamine supplementation is rare and HDIV thiamine is infrequently prescribed to patients with encephalopathy. Further studies are needed to confirm the possible benefits of HDIV thiamine for patients with suspected thiamine-deficient encephalopathy. Copyright © 2018 The Academy of Psychosomatic Medicine. Published by Elsevier Inc. All rights reserved.

  20. Calculation of residence times and radiation doses using the standard PC software Excel

    International Nuclear Information System (INIS)

    Herzog, H.; Zilken, H.; Niederbremer, A.; Friedrich, W.; Mueller-Gaertner, H.W.

    1997-01-01

    We developed a program which aims to facilitate the calculation of radiation doses to single organs and the whole body. IMEDOSE uses Excel to include calculations, graphical displays, and interactions with the user in a single general-purpose PC software tool. To start the procedure the input data are copied into a spreadsheet. They must represent percentage uptake values of several organs derived from measurements in animals or humans. To extrapolate these data up to seven half-lives of the radionuclide, fitting to one or two exponentional functions is included and can be checked by the user. By means of the approximate time-activity information the cumulated activity or residence times are calculated. Finally these data are combined with the absorbed fraction doses (S-values) given by MIRD pamphlet No. 11 to yield radiation doses, the effective dose equivalent and the effective dose. These results are presented in a final table. Interactions are realized with push-buttons and drop-down menus. Calculations use the Visual Basic tool of Excel. In order to test our program, biodistribution data of fluorine-18 fluorodeoxyglucose were taken from the literature (Meija et al., J Nucl Med 1991; 32:699-706). For a 70-kg adult the resulting radiation doses of all target organs listed in MIRD 11 were different from the ICRP 53 values by 1%±18% on the average. When the residence times were introduced into MIRDOSE3 (Stabin, J Nucl Med 1996; 37:538-546) the mean difference between our results and those of MIRDOSE3 was -3%±6%. Both outcomes indicate the validity of the present approach. (orig.)

  1. Calculation of residence times and radiation doses using the standard PC software Excel.

    Science.gov (United States)

    Herzog, H; Zilken, H; Niederbremer, A; Friedrich, W; Müller-Gärtner, H W

    1997-12-01

    We developed a program which aims to facilitate the calculation of radiation doses to single organs and the whole body. IMEDOSE uses Excel to include calculations, graphical displays, and interactions with the user in a single general-purpose PC software tool. To start the procedure the input data are copied into a spreadsheet. They must represent percentage uptake values of several organs derived from measurements in animals or humans. To extrapolate these data up to seven half-lives of the radionuclide, fitting to one or two exponentional functions is included and can be checked by the user. By means of the approximate time-activity information the cumulated activity or residence times are calculated. Finally these data are combined with the absorbed fraction doses (S-values) given by MIRD pamphlet No. 11 to yield radiation doses, the effective dose equivalent and the effective dose. These results are presented in a final table. Interactions are realized with push-buttons and drop-down menus. Calculations use the Visual Basic tool of Excel. In order to test our program, biodistribution data of fluorine-18 fluorodeoxyglucose were taken from the literature (Meija et al., J Nucl Med 1991; 32:699-706). For a 70-kg adult the resulting radiation doses of all target organs listed in MIRD 11 were different from the ICRP 53 values by 1%+/-18% on the average. When the residence times were introduced into MIRDOSE3 (Stabin, J Nucl Med 1996; 37:538-546) the mean difference between our results and those of MIRDOSE3 was -3%+/-6%. Both outcomes indicate the validity of the present approach.

  2. Calculation of residence times and radiation doses using the standard PC software Excel

    Energy Technology Data Exchange (ETDEWEB)

    Herzog, H.; Zilken, H.; Niederbremer, A.; Friedrich, W. [Institute of Medicine, Research Center Juelich, Juelich (Germany); Mueller-Gaertner, H.W. [Institute of Medicine, Research Center Juelich, Juelich (Germany)]|[Department of Nuclear Medicine, Heinrich-Heine University Hospital Duesseldorf (Germany)

    1997-12-01

    We developed a program which aims to facilitate the calculation of radiation doses to single organs and the whole body. IMEDOSE uses Excel to include calculations, graphical displays, and interactions with the user in a single general-purpose PC software tool. To start the procedure the input data are copied into a spreadsheet. They must represent percentage uptake values of several organs derived from measurements in animals or humans. To extrapolate these data up to seven half-lives of the radionuclide, fitting to one or two exponentional functions is included and can be checked by the user. By means of the approximate time-activity information the cumulated activity or residence times are calculated. Finally these data are combined with the absorbed fraction doses (S-values) given by MIRD pamphlet No. 11 to yield radiation doses, the effective dose equivalent and the effective dose. These results are presented in a final table. Interactions are realized with push-buttons and drop-down menus. Calculations use the Visual Basic tool of Excel. In order to test our program, biodistribution data of fluorine-18 fluorodeoxyglucose were taken from the literature (Meija et al., J Nucl Med 1991; 32:699-706). For a 70-kg adult the resulting radiation doses of all target organs listed in MIRD 11 were different from the ICRP 53 values by 1%{+-}18% on the average. When the residence times were introduced into MIRDOSE3 (Stabin, J Nucl Med 1996; 37:538-546) the mean difference between our results and those of MIRDOSE3 was -3%{+-}6%. Both outcomes indicate the validity of the present approach. (orig.) With 5 figs., 2 tabs., 18 refs.

  3. Methodology for correlations between doses and detectability in standard mammographic images: application in Sao Paulo state

    International Nuclear Information System (INIS)

    Furquim, Tania Aparecida Correia

    2005-01-01

    Measurements using mammography units were performed in loco in 50 health establishments, randomly sampled from an equipment list of the Cadastro Nacional de Estabelecimentos de Saude (Health Establishments Brazilian Catalog). For the measurements six phantoms were utilized to establish different quality criteria and to evaluate doses in different breast thicknesses. Two different methods of measuring average glandular doses (AGD) were applied, and measurements of entrance surface doses (ESD) were also realized, in order to obtain mean values to Sao Paulo State. A study relating distribution and properties of different mammography trademarks with doses was performed. The sensitometry of processors allowed a quantification of the film-processing contrast index, A g , establishing a state mean value. The phantom images allowed the evaluation of detection limits of structures as microcalcifications, fibers, and masses, and state mean values were established for: spatial resolution (on surface and glandular breast position); image contrast; and detection expert ability from phantom images in two situations: before knowing the image targets and after viewing of a target map. Then, the results were compared to target detections in laboratory environment. Based on dose results, A g , image contrast, maximum contrast, and detection ratio, a relationship between them was determined. The results show that, in Sao Paulo State, mean glandular doses were lower than reference levels considering the Wu method, and close to or above reference levels for ail phantoms considering the Dance method. The ESD was always close to or above reference levels. The A g presented a mean value of (10,42 ± 0,20) for Sao Paulo State, and the image contrast was lower than the required limits established by the phantom manufacturers. The high contrast resolution showed that mammography units presented the expected values of line pair per mm in the State. The detectability evaluation of local

  4. Are high doses of carbidopa a concern? A randomized clinical trial in Parkinson’s disease

    Science.gov (United States)

    Brod, Lissa S.; Aldred, Jason L.; Nutt, John G.

    2013-01-01

    Background Recommended doses of carbidopa are 75–200 mg/day. Higher doses could inhibit brain aromatic amino acid decarboxylase and reduce clinical effects. Methods We compared 4-week outpatient treatments with carbidopa 75 mg and 450 mg/day administered with levodopa on the subjects’ normal schedule. After each treatment phase subjects had two 2-hour levodopa infusions. The first infusion examined the effects of carbidopa doses administered the preceding four weeks and the second infusion determined the acute effects of the two dosages of carbidopa. The antiparkinsonian effects and levodopa and carbidopa plasma concentrations were monitored during the infusions. Results Twelve subjects completed the study. Carbidopa concentrations were eight times higher after the high carbidopa phase. Area under the curve (AUC) for clinical ratings did not differ for the four levodopa infusions although AUC for plasma levodopa was modestly increased with 450 mg of carbidopa. Nine subjects reported the high carbidopa outpatient phase was associated with greater response to levodopa. Conclusion Doses of 450 mg/day of carbidopa did not reduce the responses to levodopa infusion, extending the safe range of carbidopa to 450 mg/day. PMID:22508376

  5. Nanoscale radiation transport and clinical beam modeling for gold nanoparticle dose enhanced radiotherapy (GNPT) using X-rays.

    Science.gov (United States)

    Zygmanski, Piotr; Sajo, Erno

    2016-01-01

    We review radiation transport and clinical beam modelling for gold nanoparticle dose-enhanced radiotherapy using X-rays. We focus on the nanoscale radiation transport and its relation to macroscopic dosimetry for monoenergetic and clinical beams. Among other aspects, we discuss Monte Carlo and deterministic methods and their applications to predicting dose enhancement using various metrics.

  6. An acenocoumarol dosing algorithm exploiting clinical and genetic factors in South Indian (Dravidian) population.

    Science.gov (United States)

    Krishna Kumar, Dhakchinamoorthi; Shewade, Deepak Gopal; Loriot, Marie-Anne; Beaune, Philippe; Sai Chandran, B V; Balachander, Jayaraman; Adithan, Chandrasekaran

    2015-02-01

    The objective of this study was to determine the influence of CYP2C9, VKORC1, CYP4F2, and GGCX genetic polymorphisms on mean daily dose of acenocoumarol in South Indian patients and to develop a new pharmacogenetic algorithm based on clinical and genetic factors. Patients receiving acenocoumarol maintenance therapy (n = 230) were included in the study. Single nucleotide polymorphisms (SNP) of CYP2C9, VKORC1, CYP4F2, and GGCX were genotyped by real-time polymerase chain reaction (RT-PCR) method. The mean daily acenocoumarol maintenance dose was found to be 3.7 ± 2.3 (SD) mg/day. The CYP2C9 *1*2, CYP2C9 *1*3, and CYP2C9 *2*3 variant genotypes significantly reduced the dose by 56.7 % (2.0 mg), 67.6 % (1.6 mg), and 70.3 % (1.5 mg) than wild-type carriers 4.1 mg, p genetic variants of CYP2C9 and GGCX (rs11676382) were found to be associated with lower acenocoumarol dose, whereas CYP4F2 (rs2108622) was associated with higher doses. Age, body mass index (BMI), variation of CYP2C9, VKORC1, CYP4F2, and GGCX were the major determinants of acenocoumarol maintenance dose, accounting for 61.8 % of its variability (adjusted r (2) = 0.615, p algorithm was established to determine the acenocoumarol dose in South Indian population.

  7. [Patient dose: implementation of a clinical practice assessment in medical imaging].

    Science.gov (United States)

    Mozziconacci, J G; Ayivi, A; Bois Langlois, F; Pucheux, J

    2009-11-01

    To describe our experience with the implementation of a clinical practice assessment (CPA) with regards to radiation exposure in CT. Such a CPA requires that a reference level be available (DRL: diagnostic reference level) along with exposure data (CTDIvol and DLP) allowing for the evaluation of current practices, development of an action plan for improvement and future follow-up after implementation. The action plan for improvements was elaborated based on the review of 641 radiation exposure data points collected over 1 year (CTDIvol and DLP). These data were compared to DRL values of corresponding anatomical regions. The implementation of dose guidelines enabled continuous quality improvement as opposed to punctual radiation dose assessments. The requirement of recording patient exposure was an excellent opportunity to perform a CPA activity as described by the Haute Autorité de Santé (HAS) in its clinical audit process.

  8. Standardization of I-123-meta-iodobenzylguanidine myocardial sympathetic activity imaging: phantom calibration and clinical applications

    NARCIS (Netherlands)

    Nakajima, Kenichi; Verschure, Derk O.; Okuda, Koichi; Verberne, Hein J.

    2017-01-01

    Purpose Myocardial sympathetic imaging with I-123-meta-iodobenzylguanidine (I-123-mIBG) has gained clinical momentum. Although the need for standardization of I-123-mIBG myocardial uptake has been recognized, the availability of practical clinical standardization approaches is limited. The need for

  9. Individualized recombinant human follicle-stimulating hormone dosing using the CONSORT calculator in assisted reproductive technology: a large, multicenter, observational study of routine clinical practice.

    Science.gov (United States)

    Naether, Olaf Gj; Tandler-Schneider, Andreas; Bilger, Wilma

    2015-01-01

    This postmarketing surveillance survey was conducted to investigate the utility of the CONsistency in r-FSH Starting dOses for individualized tReatmenT (CONSORT) calculator for individualizing recombinant human follicle-stimulating hormone (r-hFSH) starting doses for controlled ovarian stimulation (COS) in routine clinical practice. This was a 3-year, open-label, observational study evaluating data from women undergoing COS for assisted reproductive technology at 31 German fertility centers. Physicians stated their recommended r-hFSH starting dose, then generated a CONSORT-recommended r-hFSH starting dose. Physicians could prescribe any r-hFSH starting dose. The primary objective was to compare the r-hFSH starting dose recommended by the physician with the CONSORT-calculated dose and that prescribed. Statistical analyses were conducted post hoc. Data were collected from 2,579 patients; the mean (standard deviation [SD]) age was 30.5 (2.93) years (range: 19-40 years). The mean (SD) CONSORT-calculated r-hFSH starting dose was significantly lower than the physician-recommended dose (134.5 [38.0] IU versus 164.6 [47.1] IU; PCONSORT-calculated doses were prescribed for 27.3% (number [n] =677) of patients, and non-CONSORT-calculated doses prescribed for 72.7% (n=1,800). The mean (SD) number of oocytes retrieved per patient was 10.6 (6.15) and 11.4 (6.66) in the CONSORT and non-CONSORT groups, respectively; the mean (SD) number of embryos transferred per patient was 1.98 (0.41) and 2.03 (0.45), respectively. Clinical pregnancy rates per COS cycle were 38.8% (CONSORT) and 34.8% (non-CONSORT) (P=0.142); clinical pregnancy rates per embryos transferred were 45.0% and 39.5%, respectively (P=0.049). Miscarriage occurred in 14.8% of all clinical pregnancies ( 12.5%; non- 15.3%). The rate of grade 3 ovarian hyperstimulation syndrome (OHSS) was 0.3% (n=2) in the CONSORT group and 0.6% (n=11) in the non-CONSORT group. OHSS led to hospitalization in 0.81% (n=21) of cases (CONSORT

  10. Multidetector CT dose: clinical practice improvement strategies from a successful optimization program.

    Science.gov (United States)

    Wallace, Anthony B; Goergen, Stacy K; Schick, Daniel; Soblusky, Tina; Jolley, Damien

    2010-08-01

    optimization enabled clinically meaningful dose reduction for a variety of common adult scans. However, access to medical radiation physicists, assistance with time-consuming data collection, and technical support from a medical imaging technologist were costly and critical to the success of the program. Crown Copyright 2010. Published by Elsevier Inc. All rights reserved.

  11. COMPARISON OF EFFICACY AND FETOMATERNAL OUTCOME WITH LOW DOSE AND STANDARD PRITCHARD’S REGIMEN OF MAGNESIUM SULPHATE IN ECLAMPSIA

    Directory of Open Access Journals (Sweden)

    Nirmala Chamakuri

    2017-11-01

    Full Text Available BACKGROUND Eclampsia, a hypertensive disorder of pregnancy is a common obstetric emergency, which leads to significant maternal morbidity, perinatal morbidity and mortality. The Pritchard’s regimen of magnesium sulphate remains as the standard regimen worldwide. The aim of this study is to compare the effectiveness, side effects and fetomaternal outcome using low-dose magnesium sulphate with the results of Pritchard regime. MATERIALS AND METHODS A comparative prospective study including 120 eclampsia patients designed into group I and group II treated with low-dose magnesium sulphate and Pritchard’s regimen was conducted in the Department of Obstetrics and Gynaecology for a period of 18 months between January 2015 to June 2016. RESULTS In the present study, there was 100% control of seizures in both the groups. No recurrence of seizures were seen in 57 (95% of cases in group II (low-dose regimen and 3 (5% cases showed recurrence, which were controlled by giving additional doses. In group II, loss of patellar reflexes was seen in 6 (10%, reduced urine output was seen in 3 (5% of cases, mild PPH was observed in 3 (5% cases and perinatal mortality in 18 (30% cases, which were lower than that of group I (Pritchard’s regimen. CONCLUSION Low-dose magnesium sulphate is effective in controlling convulsions in eclampsia. This regimen is highly suitable for use in Indian women who are known to have low body mass index

  12. The role of the standard EEG in clinical psychiatry.

    LENUS (Irish Health Repository)

    O'Sullivan, S S

    2012-02-03

    BACKGROUND: The EEG is a commonly requested test on patients attending psychiatric services, predominantly to investigate for a possible organic brain syndrome causing behavioural changes. AIMS: To assess referrals for EEG from psychiatric services in comparison with those from other sources. We determine which clinical factors were associated with an abnormal EEG in patients referred from psychiatric sources. METHODS: A retrospective review of EEG requests in a 1-year period was performed. Analysis of referral reasons for psychiatric patients was undertaken, and outcome of patients referred from psychiatric services post-EEG was reviewed. RESULTS: One thousand four hundred and seventy EEGs were reviewed, of which 91 (6.2%) were referred from psychiatry. Neurology service referrals had detection rates of abnormal EEGs of 27%, with psychiatric referrals having the lowest abnormality detection rate of 17.6% (p < 0.1). In psychiatric-referred patients the only significant predictors found of an abnormal EEG were a known history of epilepsy (p < 0.001), being on clozapine (p < 0.05), and a possible convulsive seizure (RR = 6.51). Follow-up data of 53 patients did not reveal a significant clinical impact of EEG results on patient management. CONCLUSIONS: Many patients are referred for EEG from psychiatric sources despite a relatively low index of suspicion of an organic brain disorders, based on reasons for referral documented, with an unsurprising low clinical yield.

  13. [Discussion on the standard of clinical genetic testing report and the consensus of gene testing industry].

    Science.gov (United States)

    Huang, Hui; Shen, Yiping; Gu, Weihong; Wang, Wei; Wang, Yiming; Qi, Ming; Shen, Jun; Qiu, Zhengqing; Yu, Shihui; Zhou, Zaiwei; Chen, Baixue; Chen, Lei; Chen, Yundi; Cui, Huanhuan; Du, Juan; Gao, Yong; Guo, Yiran; Hu, Chanjuan; Hu, Liang; Huang, Yi; Li, Peipei; Li, Xiaorong; Li, Xiurong; Liu, Yaping; Lu, Jie; Ma, Duan; Ma, Yongyi; Peng, Mei; Song, Fang; Sun, Hongye; Wang, Liang; Wang, Dawei; Wang, Jingmin; Wang, Ling; Wang, Zhengyuan; Wang, Zhinong; Wu, Jihong; Wu, Jing; Wu, Jian; Xu, Yimin; Yao, Hong; Yang, Dongsheng; Yang, Xu; Yang, Yanling; Zhang, Ying; Zhou, Yulin; Zhu, Baosheng; Zeng, Sicong; Peng, Zhiyu; Huang, Shangzhi

    2018-02-10

    The widespread application of next generation sequencing (NGS) in clinical settings has enabled testing, diagnosis, treatment and prevention of genetic diseases. However, many issues have arisen in the meanwhile. One of the most pressing issues is the lack of standards for reporting genetic test results across different service providers. The First Forum on Standards and Specifications for Clinical Genetic Testing was held to address the issue in Shenzhen, China, on October 28, 2017. Participants, including geneticists, clinicians, and representatives of genetic testing service providers, discussed problems of clinical genetic testing services across in China and shared opinions on principles, challenges, and standards for reporting clinical genetic test results. Here we summarize expert opinions presented at the seminar and report the consensus, which will serve as a basis for the development of standards and guidelines for reporting of clinical genetic testing results, in order to promote the standardization and regulation of genetic testing services in China.

  14. Dose intensity of standard adjuvant CMF with granulocyte colony-stimulating factor for premenopausal patients with node-positive breast cancer

    NARCIS (Netherlands)

    deGraaf, H; Willemse, PHB; Bong, SB; Piersma, H; Tjabbes, T; vanVeelen, H; Coenen, JLLM; deVries, EGE

    1996-01-01

    The effects of granulocyte colony-stimulating factor (G-CSF) on total dose and dose intensity of standard oral adjuvant CMF (cyclophosphamide, methotrexate, and 5-fluorouracil) chemotherapy were studied in premenopausal patients with node-positive breast cancer. Treatment consisted of standard CMF

  15. Dosing and switching strategies for paliperidone palmitate: based on population pharmacokinetic modelling and clinical trial data.

    Science.gov (United States)

    Samtani, Mahesh N; Gopal, Srihari; Gassmann-Mayer, Cristiana; Alphs, Larry; Palumbo, Joseph M

    2011-10-01

    Paliperidone palmitate is a second-generation, long-acting injectable (LAI) antipsychotic recently approved by the US FDA and European Medicines Agency for use in patients with schizophrenia. This article reviews the recommended dosing regimens for initiation and maintenance treatment with paliperidone palmitate in adult patients with schizophrenia. We also address issues of switching to paliperidone palmitate from other antipsychotics, managing missed doses and dosing in special patient populations. The dosing recommendations that were approved by the FDA and other regulatory agencies around the world are based on the results of population pharmacokinetic (PK) simulations and data from clinical trials that are presented in this review. A one-compartment disposition model with zero/first-order absorption best described the PK of paliperidone palmitate. Population PK models for extended-release paliperidone and long-acting risperidone were also developed and we report the results from these models. The PK profiles for 5000 patients were simulated after paliperidone palmitate injections. The population median and 90% prediction intervals of the simulated plasma concentration versus time profiles after multiple doses are graphically displayed in this review. Based on the data from model-based PK simulations, the approved recommended initiation regimen for paliperidone palmitate is 150 mg equivalent (mg eq.) paliperidone (paliperidone palmitate 234 mg) on day 1 followed by 100 mg eq. paliperidone (paliperidone palmitate 156 mg) on day 8, each administered into the deltoid muscle, using a 1-inch 23-gauge needle in those weighing paliperidone (paliperidone palmitate 39-234 mg; recommended dose of 75 mg eq. paliperidone [paliperidone palmitate 117 mg]) injected into the deltoid (needle size is weight adjusted) or gluteal (using a 1.5-inch 22-gauge needle) muscle. The day 8 dose may be administered ±2 days and monthly doses ±7 days, without a clinically

  16. Multicenter clinical evaluation of a multi-dose formulation of propofol in the dog

    OpenAIRE

    Mama, Khursheed R; Gaynor, James S; Harvey, Ralph C; Robertson, Sheilah A; Koenig, Robbin L; Cozzi, Elizabeth M

    2013-01-01

    Background Propofol is a widely used injectable anesthetic agent for induction and short-term maintenance in dogs. A multi-dose formulation of propofol (MDP) has been developed which includes 2% benzyl alcohol as a preservative. In order to document the use of the product under clinical conditions, MDP was tested in a prospective clinical trial conducted at six sites within the United States. One hundred thirty-eight healthy, client-owned dogs were assigned to one of six treatment groups base...

  17. Clinical Results after High-Dose Intensity-Modulated Radiotherapy for High-Risk Prostate Cancer

    Directory of Open Access Journals (Sweden)

    Valérie Fonteyne

    2012-01-01

    Full Text Available Purpose. Patients with high-risk prostate cancer (PC can be treated with high-dose intensity-modulated radiotherapy (IMRT and long-term androgen deprivation (AD. In this paper we report on (i late toxicity and (ii biochemical (bRFS and clinical relapse-free survival (cRFS of this combined treatment. Methods. 126 patients with high-risk PC (T3-4 or PSA >20 ng/mL or Gleason 8–10 and ≥24 months of followup were treated with high-dose IMRT and AD. Late toxicity was recorded. Biochemical relapse was defined as PSA nadir +2 ng/mL. Clinical relapse was defined as local failure or metastases. Results. The incidence of late grade 3 gastrointestinal and genitourinary toxicity was 2 and 6%, respectively. Five-year bRFS and cRFS were 73% and 86% respectively. AD was a significant predictor of bRFS (P=0.001 and cRFS (P=0.01. Conclusion. High-dose IMRT and AD for high-risk PC offers excellent biochemical and clinical control with low toxicity.

  18. Clinical implementation of dose-volume histogram predictions for organs-at-risk in IMRT planning

    International Nuclear Information System (INIS)

    Moore, K L; Appenzoller, L M; Tan, J; Michalski, J M; Thorstad, W L; Mutic, S

    2014-01-01

    True quality control (QC) of the planning process requires quantitative assessments of treatment plan quality itself, and QC in IMRT has been stymied by intra-patient anatomical variability and inherently complex three-dimensional dose distributions. In this work we describe the development of an automated system to reduce clinical IMRT planning variability and improve plan quality using mathematical models that predict achievable OAR DVHs based on individual patient anatomy. These models rely on the correlation of expected dose to the minimum distance from a voxel to the PTV surface, whereby a three-parameter probability distribution function (PDF) was used to model iso-distance OAR subvolume dose distributions. DVH models were obtained by fitting the evolution of the PDF with distance. Initial validation on clinical cohorts of 40 prostate and 24 head-and-neck plans demonstrated highly accurate model-based predictions for achievable DVHs in rectum, bladder, and parotid glands. By quantifying the integrated difference between candidate DVHs and predicted DVHs, the models correctly identified plans with under-spared OARs, validated by replanning all cases and correlating any realized improvements against the predicted gains. Clinical implementation of these predictive models was demonstrated in the PINNACLE treatment planning system by use of existing margin expansion utilities and the scripting functionality inherent to the system. To maintain independence from specific planning software, a system was developed in MATLAB to directly process DICOM-RT data. Both model training and patient-specific analyses were demonstrated with significant computational accelerations from parallelization.

  19. Calibration of dose meters used in radiotherapy

    International Nuclear Information System (INIS)

    1979-01-01

    This manual is a practical guide, not a comprehensive textbook, to the instrumentation and procedures necessary to calibrate a radiation dose meter used in clinical practice against a secondary standard dose meter

  20. Randomized, controlled, assessor-blind clinical trial to assess the efficacy of single- versus repeated-dose albendazole to treat ascaris lumbricoides, trichuris trichiura, and hookworm infection.

    Science.gov (United States)

    Adegnika, Ayola A; Zinsou, Jeannot F; Issifou, Saadou; Ateba-Ngoa, Ulysse; Kassa, Roland F; Feugap, Eliane N; Honkpehedji, Yabo J; Dejon Agobe, Jean-Claude; Kenguele, Hilaire M; Massinga-Loembe, Marguerite; Agnandji, Selidji T; Mordmüller, Benjamin; Ramharter, Michael; Yazdanbakhsh, Maria; Kremsner, Peter G; Lell, Bertrand

    2014-05-01

    In many regions where soil-transmitted helminth infections are endemic, single-dose albendazole is used in mass drug administration programs to control infections. There are little data on the efficacy of the standard single-dose administration compared to that of alternative regimens. We conducted a randomized, controlled, assessor-blinded clinical trial to determine the efficacies of standard and extended albendazole treatment against soil-transmitted helminth infection in Gabon. A total of 175 children were included. Adequate cure rates and egg reduction rates above 85% were found with a single dose of albendazole for Ascaris infection, 85% (95% confidence interval [CI], 73, 96) and 93.8% (CI, 87.6, 100), respectively, while two doses were necessary for hookworm infestation (92% [CI, 78, 100] and 92% [CI, 78, 100], respectively). However, while a 3-day regimen was not sufficient to cure Trichuris (cure rate, 83% [CI, 73, 93]), this regimen reduced the number of eggs up to 90.6% (CI, 83.1, 100). The rate ratios of two- and three-dose regimens compared to a single-dose treatment were 1.7 (CI, 1.1, 2.5) and 2.1 (CI, 1.5, 2.9) for Trichuris and 1.7 (CI, 1.0, 2.9) and 1.7 (CI, 1.0, 2.9) for hookworm. Albendazole was safe and well tolerated in all regimens. A single-dose albendazole treatment considerably reduces Ascaris infection but has only a moderate effect on hookworm and Trichuris infections. The single-dose option may still be the preferred regimen because it balances efficacy, safety, and compliance during mass drug administration, keeping in mind that asymptomatic low-level helminth carriage may also have beneficial effects. (This study has been registered at ClinicalTrials.gov under registration number NCT01192802.).

  1. "Heidelberg standard examination" and "Heidelberg standard procedures" - Development of faculty-wide standards for physical examination techniques and clinical procedures in undergraduate medical education.

    Science.gov (United States)

    Nikendei, C; Ganschow, P; Groener, J B; Huwendiek, S; Köchel, A; Köhl-Hackert, N; Pjontek, R; Rodrian, J; Scheibe, F; Stadler, A-K; Steiner, T; Stiepak, J; Tabatabai, J; Utz, A; Kadmon, M

    2016-01-01

    The competent physical examination of patients and the safe and professional implementation of clinical procedures constitute essential components of medical practice in nearly all areas of medicine. The central objective of the projects "Heidelberg standard examination" and "Heidelberg standard procedures", which were initiated by students, was to establish uniform interdisciplinary standards for physical examination and clinical procedures, and to distribute them in coordination with all clinical disciplines at the Heidelberg University Hospital. The presented project report illuminates the background of the initiative and its methodological implementation. Moreover, it describes the multimedia documentation in the form of pocketbooks and a multimedia internet-based platform, as well as the integration into the curriculum. The project presentation aims to provide orientation and action guidelines to facilitate similar processes in other faculties.

  2. Randomized clinical trial comparing fixed-time split dosing and split dosing of oral Picosulfate regimen for bowel preparation.

    Science.gov (United States)

    Jun, Jae Hyuck; Han, Koon Hee; Park, Jong Kyu; Seo, Hyun Il; Kim, Young Don; Lee, Sang Jin; Jun, Baek Gyu; Hwang, Min Sik; Park, Yoon Kyoo; Kim, Myeong Jong; Cheon, Gab Jin

    2017-08-28

    To compare the efficacy of fixed-time split dose and split dose of an oral sodium picosulfate for bowel preparation. This is study was prospective, randomized controlled study performed at a single Institution (2013-058). A total of 204 subjects were assigned to receive one of two sodium picosulfate regimens ( i.e ., fixed-time split or split) prior to colonoscopy. Main outcome measurements were bowel preparation quality and subject tolerability. There was no statistical difference between the fixed-time split dose regimen group and the split dose regimen group (Ottawa score mean 2.57 ± 1.91 vs 2.80 ± 2.51, P = 0.457). Cecal intubation time and physician's satisfaction of inspection were not significantly different between the two groups ( P = 0.428, P = 0.489). On subgroup analysis, for afternoon procedures, the fixed-time split dose regimen was equally effective as compared with the split dose regimen (Ottawa score mean 2.56 ± 1.78 vs 2.59 ± 2.27, P = 0.932). There was no difference in tolerability or compliance between the two groups. Nausea was 21.2% in the fixed-time split dose group and 14.3% in the split dose group ( P = 0.136). Vomiting was 7.1% and 2.9% ( P = 0.164), abdominal discomfort 7.1% and 4.8% ( P = 0.484), dizziness 1% and 4.8% ( P = 0.113), cold sweating 1% and 0% ( P = 0.302) and palpitation 0% and 1% ( P = 0.330), respectively. Sleep disturbance was two (2%) patients in the fixed-time split dose group and zero (0%) patient in the split dose preparation ( P = 0.143) group. A fixed-time split dose regimen with sodium picosulfate is not inferior to a split dose regimen for bowel preparation and equally effective for afternoon colonoscopy.

  3. Tumor response and toxicity after single high-dose versus standard five-day divided-dose dactinomycin in childhood rhabdomyosarcoma.

    Science.gov (United States)

    Carli, M; Pastore, G; Perilongo, G; Grotto, P; De Bernardi, B; Ceci, A; Di Tullio, M; Madon, E; Pianca, C; Paolucci, G

    1988-04-01

    This report deals with a randomized prospective multicentric clinical trial in childhood rhabdomyosarcoma (RMS) conducted to evaluate the toxicity and the effectiveness of dactinomycin (ACT-D) administered as high, single doses v five-day, divided doses administered in combination with vincristine (VCR) and cyclophosphamide (CYC). Fifty-five group III evaluable patients (pts) less than 15 years of age with tumor size greater than 5 cm in diameter, without high-risk features of CNS involvement, and 15 group IV RMS pts were randomized to receive VAC as primary chemotherapy (CT): VCR, 1.5 mg/m2 intravenously (IV) days 1 and 8; CYC, 275 mg/m2 IV days 1 through 5; and ACT-D, 0.45 mg/m2 IV days 1 through 5 every 28 days for three cycles (33 pts), or VAC-M: CYC, 150 mg/m2 intramuscularly (IM) days 1 through 7; VCR, 2.0 mg/m2 IV day 8; and ACT-D, 1.7 mg/m2 IV day 8 every 21 days for four cycles (37 pts). Major responses (complete plus partial responses [PR]) were obtained in 67% of the VAC pts and in 70% of the VAC-M pts. Toxic effects were low, and no increased toxicity was observed in pts treated with high, single-dose ACT-D. These results confirm the effectiveness and feasibility of single, high doses of ACT-D with the advantage of requiring less pt hospitalization.

  4. Submillisievert Radiation Dose Coronary CT Angiography: Clinical Impact of the Knowledge-Based Iterative Model Reconstruction.

    Science.gov (United States)

    Iyama, Yuji; Nakaura, Takeshi; Kidoh, Masafumi; Oda, Seitaro; Utsunomiya, Daisuke; Sakaino, Naritsugu; Tokuyasu, Shinichi; Osakabe, Hirokazu; Harada, Kazunori; Yamashita, Yasuyuki

    2016-11-01

    The purpose of this study was to evaluate the noise and image quality of images reconstructed with a knowledge-based iterative model reconstruction (knowledge-based IMR) in ultra-low dose cardiac computed tomography (CT). We performed submillisievert radiation dose coronary CT angiography on 43 patients. We also performed a phantom study to evaluate the influence of object size with the automatic exposure control phantom. We reconstructed clinical and phantom studies with filtered back projection (FBP), hybrid iterative reconstruction (hybrid IR), and knowledge-based IMR. We measured effective dose of patients and compared CT number, image noise, and contrast noise ratio in ascending aorta of each reconstruction technique. We compared the relationship between image noise and body mass index for the clinical study, and object size for phantom study. The mean effective dose was 0.98 ± 0.25 mSv. The image noise of knowledge-based IMR images was significantly lower than those of FBP and hybrid IR images (knowledge-based IMR: 19.4 ± 2.8; FBP: 126.7 ± 35.0; hybrid IR: 48.8 ± 12.8, respectively) (P knowledge-based IMR images was significantly higher than those of FBP and hybrid IR images (knowledge-based IMR: 29.1 ± 5.4; FBP: 4.6 ± 1.3; hybrid IR: 13.1 ± 3.5, respectively) (P knowledge-based IMR (r = 0.27, P knowledge-based IMR offers significant noise reduction and improvement in image quality in submillisievert radiation dose cardiac CT. Copyright © 2016 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

  5. A taxonomy of multinational ethical and methodological standards for clinical trials of therapeutic interventions.

    Science.gov (United States)

    Ashton, Carol M; Wray, Nelda P; Jarman, Anna F; Kolman, Jacob M; Wenner, Danielle M; Brody, Baruch A

    2011-06-01

    If trials of therapeutic interventions are to serve society's interests, they must be of high methodological quality and must satisfy moral commitments to human subjects. The authors set out to develop a clinical-trials compendium in which standards for the ethical treatment of human subjects are integrated with standards for research methods. The authors rank-ordered the world's nations and chose the 31 with >700 active trials as of 24 July 2008. Governmental and other authoritative entities of the 31 countries were searched, and 1004 English-language documents containing ethical and/or methodological standards for clinical trials were identified. The authors extracted standards from 144 of those: 50 designated as 'core', 39 addressing trials of invasive procedures and a 5% sample (N=55) of the remainder. As the integrating framework for the standards we developed a coherent taxonomy encompassing all elements of a trial's stages. Review of the 144 documents yielded nearly 15 000 discrete standards. After duplicates were removed, 5903 substantive standards remained, distributed in the taxonomy as follows: initiation, 1401 standards, 8 divisions; design, 1869 standards, 16 divisions; conduct, 1473 standards, 8 divisions; analysing and reporting results, 997 standards, four divisions; and post-trial standards, 168 standards, 5 divisions. The overwhelming number of source documents and standards uncovered in this study was not anticipated beforehand and confirms the extraordinary complexity of the clinical trials enterprise. This taxonomy of multinational ethical and methodological standards may help trialists and overseers improve the quality of clinical trials, particularly given the globalisation of clinical research.

  6. A taxonomy of multinational ethical and methodological standards for clinical trials of therapeutic interventions

    Science.gov (United States)

    Ashton, Carol M; Wray, Nelda P; Jarman, Anna F; Kolman, Jacob M; Wenner, Danielle M; Brody, Baruch A

    2013-01-01

    Background If trials of therapeutic interventions are to serve society’s interests, they must be of high methodological quality and must satisfy moral commitments to human subjects. The authors set out to develop a clinical-trials compendium in which standards for the ethical treatment of human subjects are integrated with standards for research methods. Methods The authors rank-ordered the world’s nations and chose the 31 with >700 active trials as of 24 July 2008. Governmental and other authoritative entities of the 31 countries were searched, and 1004 English-language documents containing ethical and/or methodological standards for clinical trials were identified. The authors extracted standards from 144 of those: 50 designated as ‘core’, 39 addressing trials of invasive procedures and a 5% sample (N=55) of the remainder. As the integrating framework for the standards we developed a coherent taxonomy encompassing all elements of a trial’s stages. Findings Review of the 144 documents yielded nearly 15 000 discrete standards. After duplicates were removed, 5903 substantive standards remained, distributed in the taxonomy as follows: initiation, 1401 standards, 8 divisions; design, 1869 standards, 16 divisions; conduct, 1473 standards, 8 divisions; analysing and reporting results, 997 standards, four divisions; and post-trial standards, 168 standards, 5 divisions. Conclusions The overwhelming number of source documents and standards uncovered in this study was not anticipated beforehand and confirms the extraordinary complexity of the clinical trials enterprise. This taxonomy of multinational ethical and methodological standards may help trialists and overseers improve the quality of clinical trials, particularly given the globalisation of clinical research. PMID:21429960

  7. Accuracy of Dose Calibrators for 68Ga PET Imaging: Unexpected Findings in a Multicenter Clinical Pretrial Assessment.

    Science.gov (United States)

    Bailey, Dale L; Hofman, Michael S; Forwood, Nicholas J; O'Keefe, Graeme J; Scott, Andrew M; van Wyngaardt, Winifred M; Howe, Bonnie; Kovacev, Olga; Francis, Roslyn J

    2018-04-01

    We report the discovery of a systematic miscalibration during the work-up process for site validation of a multicenter clinical PET imaging trial using 68 Ga, which manifested as a consistent and reproducible underestimation in the quantitative accuracy (assessed by SUV) of a range of PET systems from different manufacturers at several different facilities around Australia. Methods: Sites were asked to follow a strict preparation protocol to create a radioactive phantom with 68 Ga to be imaged using a standard clinical protocol before commencing imaging in the trial. All sites had routinely used 68 Ga for clinical PET imaging for many years. The reconstructed image data were transferred to an imaging core laboratory for analysis, along with information about ancillary equipment such as the radionuclide dose calibrator. Fourteen PET systems were assessed from 10 nuclear medicine facilities in Australia, with the aim for each PET system being to produce images within 5% of the true SUV. Results: At initial testing, 10 of the 14 PET systems underestimated the SUV by 15% on average (range, 13%-23%). Multiple PET systems at one site, from two different manufacturers, were all similarly affected, suggesting a common cause. We eventually identified an incorrect factory-shipped dose calibrator setting from a single manufacturer as being the cause. The calibrator setting for 68 Ga was subsequently adjusted by the users so that the reconstructed images produced accurate values. Conclusion: PET imaging involves a chain of measurements and calibrations to produce accurate quantitative performance. Testing of the entire chain is simple, however, and should form part of any quality assurance program or prequalifying site assessment before commencing a quantitative imaging trial or clinical imaging. © 2018 by the Society of Nuclear Medicine and Molecular Imaging.

  8. Clinical relevance of different dose calculation strategies for mediastinal IMRT in Hodgkin's disease

    Energy Technology Data Exchange (ETDEWEB)

    Koeck, J.; Stieler, F.; Fleckenstein, J.; Wenz, F.; Lohr, F. [Universitaetsmedizin Mannheim, Heidelberg Univ., Mannheim (Germany). Klinik fuer Strahlentherapie und Radioonkologie; Abo-Madyan, Y. [Universitaetsmedizin Mannheim, Heidelberg Univ., Mannheim (Germany). Klinik fuer Strahlentherapie und Radioonkologie; Cairo Univ. (Egypt). Dept. of Radiation Oncology; Eich, H.T. [Muenster Univ. (Germany). Dept. of Radiation Oncology; Kriz, J.; Mueller, R.P. [Klinikum der Universitaet zu Koeln (Germany). Universitaetsklinik und Poliklinik fuer Strahlentherapie

    2012-08-15

    Background and purpose: Conventional algorithms show uncertainties in dose calculation already for three-dimensional conformal radiotherapy (3D-CRT). Intensity-modulated radiotherapy (IMRT) might even increase these. We wanted to assess differences in dose distribution for pencil beam (PB), collapsed cone (CC), and Monte Carlo (MC) algorithm for both 3D-CRT and IMRT in patients with mediastinal Hodgkin lymphoma. Patients and methods: Based on 20 computed tomograph (CT) datasets of patients with mediastinal Hodgkin lymphoma, we created treatment plans according to the guidelines of the German Hodgkin Study Group (GHSG) with PB and CC algorithm for 3D-CRT and with PB and MC algorithm for IMRT. Doses were compared for planning target volume (PTV) and organs at risk. Results: For 3D-CRT, PB overestimated PTV{sub 95} and V{sub 20} of the lung by 6.9% and 3.3% and underestimated V{sub 10} of the lung by 5.8%, compared to the CC algorithm. For IMRT, PB overestimated PTV{sub 95}, V{sub 20} of the lung, V{sub 25} of the heart and V{sub 10} of the female left/right breast by 8.1%, 25.8%, 14.0% and 43.6%/189.1%, and underestimated V{sub 10} of the lung, V{sub 4} of the heart and V{sub 4} of the female left/right breast by 6.3%, 6.8% and 23.2%/15.6%, compared to MC. Conclusion: The PB algorithm underestimates low doses to the organs at risk and overestimates dose to PTV and high doses to the organs at risk. For 3D-CRT, a well-modeled PB algorithm is clinically acceptable; for IMRT planning, however, an advanced algorithm such as CC or MC should be used at least for part of the plan optimization. (orig.)

  9. Clinical relevance of different dose calculation strategies for mediastinal IMRT in Hodgkin's disease

    International Nuclear Information System (INIS)

    Koeck, J.; Stieler, F.; Fleckenstein, J.; Wenz, F.; Lohr, F.; Abo-Madyan, Y.; Cairo Univ.; Eich, H.T.; Kriz, J.; Mueller, R.P.

    2012-01-01

    Background and purpose: Conventional algorithms show uncertainties in dose calculation already for three-dimensional conformal radiotherapy (3D-CRT). Intensity-modulated radiotherapy (IMRT) might even increase these. We wanted to assess differences in dose distribution for pencil beam (PB), collapsed cone (CC), and Monte Carlo (MC) algorithm for both 3D-CRT and IMRT in patients with mediastinal Hodgkin lymphoma. Patients and methods: Based on 20 computed tomograph (CT) datasets of patients with mediastinal Hodgkin lymphoma, we created treatment plans according to the guidelines of the German Hodgkin Study Group (GHSG) with PB and CC algorithm for 3D-CRT and with PB and MC algorithm for IMRT. Doses were compared for planning target volume (PTV) and organs at risk. Results: For 3D-CRT, PB overestimated PTV 95 and V 20 of the lung by 6.9% and 3.3% and underestimated V 10 of the lung by 5.8%, compared to the CC algorithm. For IMRT, PB overestimated PTV 95 , V 20 of the lung, V 25 of the heart and V 10 of the female left/right breast by 8.1%, 25.8%, 14.0% and 43.6%/189.1%, and underestimated V 10 of the lung, V 4 of the heart and V 4 of the female left/right breast by 6.3%, 6.8% and 23.2%/15.6%, compared to MC. Conclusion: The PB algorithm underestimates low doses to the organs at risk and overestimates dose to PTV and high doses to the organs at risk. For 3D-CRT, a well-modeled PB algorithm is clinically acceptable; for IMRT planning, however, an advanced algorithm such as CC or MC should be used at least for part of the plan optimization. (orig.)

  10. Population pharmacokinetics of exendin-(9-39) and clinical dose selection in patients with congenital hyperinsulinism.

    Science.gov (United States)

    Ng, Chee M; Tang, Fei; Seeholzer, Steven H; Zou, Yixuan; De León, Diva D

    2018-03-01

    Congenital hyperinsulinism (HI) is the most common cause of persistent hypoglycaemia in infants and children. Exendin-(9-39), an inverse glucagon-like peptide 1 (GLP-1) agonist, is a novel therapeutic agent for HI that has demonstrated glucose-raising effect. We report the first population pharmacokinetic (PopPK) model of the exendin-(9-39) in patients with HI and propose the optimal dosing regimen for future clinical trials in neonates with HI. A total of 182 pharmacokinetic (PK) observations from 26 subjects in three clinical studies were included for constructing the PopPK model using first order conditional estimation (FOCE) with interaction method in nonlinear mixed-effects modelling (NONMEM). Exposure metrics (area under the curve [AUC] and maximum plasma concentration [C max ]) at no observed adverse effect levels (NOAELs) in rats and dogs were determined in toxicology studies. Observed concentration-time profiles of exendin-(9-39) were described by a linear two-compartmental PK model. Following allometric scaling of PK parameters, age and creatinine clearance did not significantly affect clearance. The calculated clearance and elimination half-life for adult subjects with median weight of 69 kg were 11.8 l h -1 and 1.81 h, respectively. The maximum recommended starting dose determined from modelling and simulation based on the AUC 0-last at the NOAEL and predicted AUC 0-inf using the PopPK model was 27 mg kg -1  day -1 intravenously. This is the first study to investigate the PopPK of exendin-(9-39) in humans. The final PopPK model was successfully used with preclinical toxicology findings to propose the optimal dosing regimen of exendin-(9-39) for clinical studies in neonates with HI, allowing for a more targeted dosing approach to achieve desired glycaemic response. © 2017 The British Pharmacological Society.

  11. Iterative Development and Evaluation of a Pharmacogenomic-Guided Clinical Decision Support System for Warfarin Dosing.

    Science.gov (United States)

    Melton, Brittany L; Zillich, Alan J; Saleem, Jason; Russ, Alissa L; Tisdale, James E; Overholser, Brian R

    2016-11-23

    Pharmacogenomic-guided dosing has the potential to improve patient outcomes but its implementation has been met with clinical challenges. Our objective was to develop and evaluate a clinical decision support system (CDSS) for pharmacogenomic-guided warfarin dosing designed for physicians and pharmacists. Twelve physicians and pharmacists completed 6 prescribing tasks using simulated patient scenarios in two iterations (development and validation phases) of a newly developed pharmacogenomic-driven CDSS prototype. For each scenario, usability was measured via efficiency, recorded as time to task completion, and participants' perceived satisfaction which were compared using Kruskal-Wallis and Mann Whitney U tests, respectively. Debrief interviews were conducted and qualitatively analyzed. Usability findings from the first (i.e. development) iteration were incorporated into the CDSS design for the second (i.e. validation) iteration. During the CDSS validation iteration, participants took more time to complete tasks with a median (IQR) of 183 (124-247) seconds versus 101 (73.5-197) seconds in the development iteration (p=0.01). This increase in time on task was due to the increase in time spent in the CDSS corresponding to several design changes. Efficiency differences that were observed between pharmacists and physicians in the development iteration were eliminated in the validation iteration. The increased use of the CDSS corresponded to a greater acceptance of CDSS recommended doses in the validation iteration (4% in the first iteration vs. 37.5% in the second iteration, piterations but the qualitative analysis revealed greater trust in the second prototype. A pharmacogenomic-guided CDSS has been developed using warfarin as the test drug. The final CDSS prototype was trusted by prescribers and significantly increased the time using the tool and acceptance of the recommended doses. This study is an important step toward incorporating pharmacogenomics into CDSS design

  12. Standardized Patients Provide a Reliable Assessment of Athletic Training Students' Clinical Skills

    Science.gov (United States)

    Armstrong, Kirk J.; Jarriel, Amanda J.

    2016-01-01

    Context: Providing students reliable objective feedback regarding their clinical performance is of great value for ongoing clinical skill assessment. Since a standardized patient (SP) is trained to consistently portray the case, students can be assessed and receive immediate feedback within the same clinical encounter; however, no research, to our…

  13. Beneficial effect of low dose Amlodipine vs Nifedipine on serum cholesterol profile of rabbits receiving standard diet.

    Directory of Open Access Journals (Sweden)

    Bavane DS, Rajesh CS, Gurudatta Moharir, Bharatha Ambadasu

    2013-01-01

    Full Text Available To investigate the effect of low dose amlodipine v/s nifedipine on serum cholesterol profile of rabbits receiving standard diet. Methods: Fourty Newzealand rabbits were selected for the study. Their cholesterol profile was estimated at the beginning of the study. Rabbits were grouped into 4 groups receiving standard diet (control group, standard diet + vehicle propylene glycol, standard diet + nifedipine dissolved in propylene glycol and standard diet + amlodipine dissolved in propylene glycol. Along with standard diet they were treated with respective drugs for ten weeks. At the end of ten weeks serum cholesterol profile was estimated. Results: The cholesterol profile was estimated at the beginning and at the end of ten weeks. Total cholesterol in the amlodipine group decreased from 97±4.06 mg/dl to 90±4.2 mg/dl and HDL-Cholesterol increased from 32.01±4.40 mg/dl to 37±4.60 mg/dl after 10 week treatment but these changes were not significant. LDL cholesterol decreased significantly in rabbits with low dose of amlodipine from 55.42±3.32 mg/dl to 32.40±3.22 mg/dl and. In the nifedipine group there was a slight increase in total cholesterol from 102.49±5.16 mg/dl to 106±5.39 mg/dl, HDL cholesterol from 34.10±2.80 to 35.16±2.82 mg/dl and LDL cholesterol also increased from 56.20±2.20 mg/dl to 59.00±2.20 mg/dl after 10 week treatment. Conclusion: The study shows amlodipine produces favorable alterations in serum cholesterol profile

  14. The international protocol for the dosimetry of external radiotherapy beams based on standards of absorbed dose to water

    International Nuclear Information System (INIS)

    Andreo, P.

    2001-01-01

    An International Code of Practice (CoP, or dosimetry protocol) for external beam radiotherapy dosimetry based on standards of absorbed dose to water has been published by the IAEA on behalf of IAEA, WHO, PAHO and ESTRO. The CoP provides a systematic and internationally unified approach for the determination of the absorbed dose to water in reference conditions with radiotherapy beams. The development of absorbed-dose-to-water standards for high-energy photons and electrons offers the possibility of reducing the uncertainty in the dosimetry of radiotherapy beams. Many laboratories already provide calibrations at the radiation quality of 60Co gamma-rays and some have extended calibrations to high-energy photon and electron beams. The dosimetry of kilovoltage x-rays, as well as that of proton and ion beams can also be based on these standards. Thus, a coherent dosimetry system based on the same formalism is achieved for practically all radiotherapy beams. The practical use of the CoP as simple. The document is formed by a set of different CoPs for each radiation type, which include detailed procedures and worksheets. All CoPs are based on ND,w chamber calibrations at a reference beam quality Qo, together with radiation beam quality correction factors kQ preferably measured directly for the user's chamber in a standards laboratory. Calculated values of kQ are provided together with their uncertainty estimates. Beam quality specifiers are 60Co, TPR20,10 (high-energy photons), R50 (electrons), HVL and kV (x-rays) and Rres (protons and ions) [es

  15. Dose-dependent LDL-cholesterol lowering effect by plant stanol ester consumption: clinical evidence

    Directory of Open Access Journals (Sweden)

    Laitinen Kirsi

    2012-10-01

    Full Text Available Abstract Elevated serum lipids are linked to cardiovascular diseases calling for effective therapeutic means to reduce particularly LDL-cholesterol (LDL-C levels. Plant stanols reduce levels of LDL-C by partly blocking cholesterol absorption. Accordingly the consumption of foods with added plant stanols, typically esterified with vegetable oil fatty acids in commercial food products, are recommended for lowering serum cholesterol levels. A daily intake of 1.5 to 2.4 g of plant stanols has been scientifically evaluated to lower LDL-C by 7 to 10% in different populations, ages and with different diseases. Based on earlier studies, a general understanding is that no further reduction may be achieved in intakes in excess of approximately 2.5 g/day. Recent studies however suggest that plant stanols show a continuous dose–response effect in serum LDL-C lowering. This review discusses the evidence for a dose-effect relationship between plant stanol ester consumption and reduction of LDL-C concentrations with daily intakes of plant stanols of 4 g/day or more. We identified five such studies and the overall data demonstrate a linear dose-effect relationship with the most pertinent LDL-Cholesterol lowering outcome, 18%, achieved by a daily intake of 9 to 10 g of plant stanols. Along with reduction in LDL-C, the studies demonstrated a decrease in cholesterol absorption markers, the serum plant sterol to cholesterol ratios, by increasing the dose of plant stanol intake. None of the studies with daily intakes up to 10 g of plant stanols reported adverse clinical or biochemical effects from plant stanols. In a like manner, the magnitude of decrease in serum antioxidant vitamins was not related to the dose of plant stanols consumed and the differences between plant stanol ester consumers and controls were minor and insignificant or nonexisting. Consumption of plant stanols in high doses is feasible as a range of food products are commercially available for

  16. Clinical predictors of failing one dose of methotrexate for ectopic pregnancy after in vitro fertilization.

    Science.gov (United States)

    Brady, Paula C; Missmer, Stacey A; Farland, Leslie V; Ginsburg, Elizabeth S

    2017-03-01

    The aim of this study is to investigate the clinical predictors of failure of a single dose of methotrexate (MTX) for management of ectopic pregnancy after in vitro fertilization (IVF). A retrospective cohort study was performed of women who conceived ectopic pregnancies following fresh or frozen IVF cycles at an academic infertility clinic between 2007 and 2014, and received intramuscular MTX (50 mg/m 2 ). Successful single-dose MTX treatment was defined as a serum beta-human chorionic gonadotropin (hCG) decline ≥15% between days 4 and 7 post-treatment. Logistic regression models adjusted for oocyte age, number of embryos transferred, and prior ectopic pregnancy were used to estimate the adjusted odds ratio (OR) (95% confidence interval [CI]) of failing one dose of MTX. Sixty-four patients with ectopic pregnancies after IVF were included. Forty required only one dose of MTX (62.5%), while 15 required additional MTX alone (up to four total doses, 23.4%), and 9 required surgery (14.1%). By multivariable logistic regression, the highest tertiles of serum hCG at peak (≥499 IU/L, OR = 9.73, CI 1.88-50.25) and at first MTX administration (≥342 IU/L, OR = 4.74, CI 1.11-20.26), fewer embryos transferred (OR = 0.37 per each additional embryo transferred, CI 0.19-0.74), and adnexal mass by ultrasound (OR = 3.65, CI 1.10-12.11) were each correlated with greater odds of requiring additional MTX and/or surgery. This is the first study to report that in women with ectopic pregnancies after IVF, higher hCG-though well below treatment failure thresholds previously described in spontaneous pregnancies-fewer embryos transferred, and adnexal masses are associated with greater odds of failing one dose of MTX. These findings can be used to counsel IVF patients regarding the likelihood of success with single-dose MTX.

  17. Innovations for phase I dose-finding designs in pediatric oncology clinical trials

    Science.gov (United States)

    Doussau, Adelaide; Geoerger, Birgit; Jiménez, Irene; Paoletti, Xavier

    2016-01-01

    Phase I oncology clinical trials are designed to identify the optimal dose that will be recommended for phase II trials. In pediatric oncology, the conduct of those trials raise specific challenges, as the disease is rare with limited therapeutic options. In addition, the tolerance profile is known from adult trials. This paper provides a review of the major recent developments in the design of these trials, inspired by the need to cope with the specific challenges of dose finding in cancer pediatric oncology. We reviewed simulation studies comparing designs dedicated to address these challenges. We also reviewed the design used in published dose-finding trials in pediatric oncology over the period 2009–2014. Three main fields of innovation were identified. First, designs that were developed in order to relax the rules for more flexible inclusions. Second, methods to incorporate data emerging from adult studies. Third, designs accounting for toxicity evaluation at repeated cycles in pediatric oncology. In addition to this overview, we propose some further directions for designing pediatric dose-finding trials. PMID:26825023

  18. Modelling of electron contamination in clinical photon beams for Monte Carlo dose calculation

    International Nuclear Information System (INIS)

    Yang, J; Li, J S; Qin, L; Xiong, W; Ma, C-M

    2004-01-01

    The purpose of this work is to model electron contamination in clinical photon beams and to commission the source model using measured data for Monte Carlo treatment planning. In this work, a planar source is used to represent the contaminant electrons at a plane above the upper jaws. The source size depends on the dimensions of the field size at the isocentre. The energy spectra of the contaminant electrons are predetermined using Monte Carlo simulations for photon beams from different clinical accelerators. A 'random creep' method is employed to derive the weight of the electron contamination source by matching Monte Carlo calculated monoenergetic photon and electron percent depth-dose (PDD) curves with measured PDD curves. We have integrated this electron contamination source into a previously developed multiple source model and validated the model for photon beams from Siemens PRIMUS accelerators. The EGS4 based Monte Carlo user code BEAM and MCSIM were used for linac head simulation and dose calculation. The Monte Carlo calculated dose distributions were compared with measured data. Our results showed good agreement (less than 2% or 2 mm) for 6, 10 and 18 MV photon beams

  19. Imaging Radiation Doses and Associated Risks and Benefits in Subjects Participating in Breast Cancer Clinical Trials.

    Science.gov (United States)

    Fresco, Rodrigo; Spera, Gonzalo; Meyer, Carlos; Cabral, Pablo; Mackey, John R

    2015-07-01

    Medical imaging is commonly required in breast cancer (BC) clinical trials to assess the efficacy and/or safety of study interventions. Despite the lack of definitive epidemiological data linking imaging radiation with cancer development in adults, concerns exist about the risks of imaging radiation-induced malignancies (IRIMs) in subjects exposed to repetitive imaging. We estimated the imaging radiation dose and IRIM risk in subjects participating in BC trials. The imaging protocol requirements in 10 phase III trials in the adjuvant and advanced settings were assessed to estimate the effective radiation dose received by a typical and fully compliant subject in each trial. For each study, the excess lifetime attributable cancer risk (LAR) was calculated using the National Cancer Institute's Radiation Risk Assessment Tool, version 3.7.1. Dose and risk calculations were performed for both imaging intensive and nonintensive approaches to reflect the variability in imaging performed within the studies. The total effective imaging radiation dose was 0.4-262.2 mSv in adjuvant trials and 26-241.3 mSv in metastatic studies. The dose variability resulted from differing protocol requirements and imaging intensity approaches, with computed tomography, multigated acquisition scans, and bone scans as the major contributors. The mean LAR was 1.87-2,410/100,000 in adjuvant trials (IRIM: 0.0002%-2.41% of randomized subjects) and 6.9-67.3/100,000 in metastatic studies (IRIM: 0.007%-0.067% of subjects). IRIMs are infrequent events. In adjuvant trials, aligning the protocol requirements with the clinical guidelines' surveillance recommendations and substituting radiating procedures with equivalent nonradiating ones would reduce IRIM risk. No significant risk has been observed in metastatic trials, and potential concerns on IRIMs are not justified. Medical imaging is key in breast cancer (BC) clinical trials. Most of these procedures expose patients to ionizing radiation, and the risk

  20. Assessment of the image contrast improvement and dose reduction in mammography with synchrotron radiation compared to standard units

    CERN Document Server

    Moeckli, R; Fiedler, S; Pachoud, M; Hessler, C; Meuli, R; Valley, J F

    2001-01-01

    An objective method was used to evaluate image quality and dose in mammography with synchrotron radiation and to compare them to standard units. It was performed systematically in the energy range of interest for mammography through the evaluation of the contrast and the measurement of the mean glandular dose. Synchrotron radiation measurements were performed at the ESRF and a slit was placed between the test object and the screen-film system in order to reduce scatter. The conventional films were obtained on mammography units with an anti-scatter grid. In a recent paper, it was shown that the use of synchrotron radiation leads to a noticeable improvement of the image quality-dose relationship (Moeckli et al. Phys. Med. Biol. 45(12)3509). The reason of that enhancement is partly due to the monochromaticity of the synchrotron beam and partly due to the use of a slit instead of a grid. The dose reduction with synchrotron radiation can be attributed to a better X-ray total transmission of the slit and the contra...

  1. Treatment of Amblyopia Using Personalized Dosing Strategies: Statistical Modelling and Clinical Implementation.

    Science.gov (United States)

    Wallace, Michael P; Stewart, Catherine E; Moseley, Merrick J; Stephens, David A; Fielder, Alistair R

    2016-12-01

    To generate a statistical model for personalizing a patient's occlusion therapy regimen. Statistical modelling was undertaken on a combined data set of the Monitored Occlusion Treatment of Amblyopia Study (MOTAS) and the Randomized Occlusion Treatment of Amblyopia Study (ROTAS). This exercise permits the calculation of future patients' total effective dose (TED)-that predicted to achieve their best attainable visual acuity. Daily patching regimens (hours/day) can be calculated from the TED. Occlusion data for 149 study participants with amblyopia (anisometropic in 50, strabismic in 43, and mixed in 56) were analyzed. Median time to best observed visual acuity was 63 days (25% and 75% quartiles; 28 and 91 days). Median visual acuity in the amblyopic eye at start of occlusion was 0.40 logMAR (quartiles 0.22 and 0.68 logMAR) and at end of occlusion was 0.12 (quartiles 0.025 and 0.32 logMAR). Median lower and upper estimates of TED were 120 hours (quartiles 34 and 242 hours), and 176 hours (quartiles 84 and 316 hours). The data suggest a piecewise linear relationship (P = 0.008) between patching dose-rate (hours/day) and TED with a single breakpoint estimated at 2.16 (standard error 0.51) hours/day, suggesting doses below 2.16 hours/day are less effective. We introduce the concept of TED of occlusion. Predictors for TED are visual acuity deficit, amblyopia type, and age at start of occlusion therapy. Dose-rates prescribed within the model range from 2.5 to 12 hours/day and can be revised dynamically throughout treatment in response to recorded patient compliance: a personalized dosing strategy.

  2. A hybrid electron and photon IMRT planning technique that lowers normal tissue integral patient dose using standard hardware.

    Science.gov (United States)

    Rosca, Florin

    2012-06-01

    To present a mixed electron and photon IMRT planning technique using electron beams with an energy range of 6-22 MeV and standard hardware that minimizes integral dose to patients for targets as deep as 7.5 cm. Ten brain cases, two lung, a thyroid, an abdominal, and a parotid case were planned using two planning techniques: a photon-only IMRT (IMRT) versus a mixed modality treatment (E+IMRT) that includes an enface electron beam and a photon IMRT portion that ensures a uniform target coverage. The electron beam is delivered using a regular cutout placed in an electron cone. The electron energy was chosen to provide a good trade-off between minimizing integral dose and generating a uniform, deliverable plan. The authors choose electron energies that cover the deepest part of PTV with the 65%-70% isodose line. The normal tissue integral dose, the dose for ring structures around the PTV, and the volumes of the 75%, 50%, and 25% isosurfaces were used to compare the dose distributions generated by the two planning techniques. The normal tissue integral dose was lowered by about 20% by the E+IMRT plans compared to the photon-only IMRT ones for most studied cases. With the exception of lungs, the dose reduction associated to the E+IMRT plans was more pronounced further away from the target. The average dose ratio delivered to the 0-2 cm and the 2-4 cm ring structures for brain patients for the two planning techniques were 89.6% and 70.8%, respectively. The enhanced dose sparing away from the target for the brain patients can also be observed in the ratio of the 75%, 50%, and 25% isodose line volumes for the two techniques, which decreases from 85.5% to 72.6% and further to 65.1%, respectively. For lungs, the lateral electron beams used in the E+IMRT plans were perpendicular to the mostly anterior/posterior photon beams, generating much more conformal plans. The authors proved that even using the existing electron delivery hardware, a mixed electron/photon planning

  3. Clinical evaluation of a dose monitoring software tool based on Monte Carlo Simulation in assessment of eye lens doses for cranial CT scans

    Energy Technology Data Exchange (ETDEWEB)

    Guberina, Nika; Suntharalingam, Saravanabavaan; Nassenstein, Kai; Forsting, Michael; Theysohn, Jens; Wetter, Axel; Ringelstein, Adrian [University Hospital Essen, Institute of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany)

    2016-10-15

    The aim of this study was to verify the results of a dose monitoring software tool based on Monte Carlo Simulation (MCS) in assessment of eye lens doses for cranial CT scans. In cooperation with the Federal Office for Radiation Protection (Neuherberg, Germany), phantom measurements were performed with thermoluminescence dosimeters (TLD LiF:Mg,Ti) using cranial CT protocols: (I) CT angiography; (II) unenhanced, cranial CT scans with gantry angulation at a single and (III) without gantry angulation at a dual source CT scanner. Eye lens doses calculated by the dose monitoring tool based on MCS and assessed with TLDs were compared. Eye lens doses are summarized as follows: (I) CT angiography (a) MCS 7 mSv, (b) TLD 5 mSv; (II) unenhanced, cranial CT scan with gantry angulation, (c) MCS 45 mSv, (d) TLD 5 mSv; (III) unenhanced, cranial CT scan without gantry angulation (e) MCS 38 mSv, (f) TLD 35 mSv. Intermodality comparison shows an inaccurate calculation of eye lens doses in unenhanced cranial CT protocols at the single source CT scanner due to the disregard of gantry angulation. On the contrary, the dose monitoring tool showed an accurate calculation of eye lens doses at the dual source CT scanner without gantry angulation and for CT angiography examinations. The dose monitoring software tool based on MCS gave accurate estimates of eye lens doses in cranial CT protocols. However, knowledge of protocol and software specific influences is crucial for correct assessment of eye lens doses in routine clinical use. (orig.)

  4. Randomized, Multicenter Trial on the Effect of Radiation Therapy on Plantar Fasciitis (Painful Heel Spur) Comparing a Standard Dose With a Very Low Dose: Mature Results After 12 Months' Follow-Up

    International Nuclear Information System (INIS)

    Niewald, Marcus; Seegenschmiedt, M. Heinrich; Micke, Oliver; Graeber, Stefan; Muecke, Ralf; Schaefer, Vera; Scheid, Christine; Fleckenstein, Jochen; Licht, Norbert; Ruebe, Christian

    2012-01-01

    Purpose: To conduct a randomized trial of radiation therapy for painful heel spur, comparing a standard dose with a very low dose. Methods and Materials: Sixty-six patients were randomized to receive radiation therapy either with a total dose of 6.0 Gy applied in 6 fractions of 1.0 Gy twice weekly (standard dose) or with a total dose of 0.6 Gy applied in 6 fractions of 0.1 Gy twice weekly (low dose). In all patients lateral opposing 4- to 6-MV photon beams were used. The results were measured using a visual analogue scale, the Calcaneodynia score, and the SF12 health survey. The fundamental phase of the study ended after 3 months, and the follow-up was continued up to 1 year. Patients with insufficient pain relief after 3 months were offered reirradiation with the standard dosage at any time afterward. Results: Of 66 patients, 4 were excluded because of withdrawal of consent or screening failures. After 3 months the results in the standard arm were highly significantly superior compared with those in the low-dose arm (visual analogue scale, P=.001; Calcaneodynia score, P=.027; SF12, P=.045). The accrual of patients was stopped at this point. Further evaluation after 12 months' follow-up showed the following results: (1) highly significant fewer patients were reirradiated in the standard arm compared with the low-dose arm (P<.001); (2) the results of patients in the low-dose arm who were reirradiated were identical to those in the standard arm not reirradiated (reirradiation as a salvage therapy if the lower dose was ineffective); (3) patients experiencing a favorable result after 3 months showed this even after 12 months, and some results even improved further between 3 and 12 months. Conclusions: This study confirms the superior analgesic effect of radiation therapy with 6-Gy doses on painful heel spur even for a longer time period of at least 1 year.

  5. Dose properties of a laser accelerated electron beam and prospects for clinical application

    International Nuclear Information System (INIS)

    Kainz, K.K.; Hogstrom, K.R.; Antolak, J.A.; Almond, P.R.; Bloch, C.D.; Chiu, C.; Fomytskyi, M.; Raischel, F.; Downer, M.; Tajima, T.

    2004-01-01

    Laser wakefield acceleration (LWFA) technology has evolved to where it should be evaluated for its potential as a future competitor to existing technology that produces electron and x-ray beams. The purpose of the present work is to investigate the dosimetric properties of an electron beam that should be achievable using existing LWFA technology, and to document the necessary improvements to make radiotherapy application for LWFA viable. This paper first qualitatively reviews the fundamental principles of LWFA and describes a potential design for a 30 cm accelerator chamber containing a gas target. Electron beam energy spectra, upon which our dose calculations are based, were obtained from a uniform energy distribution and from two-dimensional particle-in-cell (2D PIC) simulations. The 2D PIC simulation parameters are consistent with those reported by a previous LWFA experiment. According to the 2D PIC simulations, only approximately 0.3% of the LWFA electrons are emitted with an energy greater than 1 MeV. We studied only the high-energy electrons to determine their potential for clinical electron beams of central energy from 9 to 21 MeV. Each electron beam was broadened and flattened by designing a dual scattering foil system to produce a uniform beam (103%>off-axis ratio>95%) over a 25x25 cm2 field. An energy window (ΔE) ranging from 0.5 to 6.5 MeV was selected to study central-axis depth dose, beam flatness, and dose rate. Dose was calculated in water at a 100 cm source-to-surface distance using the EGS/BEAM Monte Carlo algorithm. Calculations showed that the beam flatness was fairly insensitive to ΔE. However, since the falloff of the depth-dose curve (R 10 -R 90 ) and the dose rate both increase with ΔE, a tradeoff between minimizing (R 10 -R 90 ) and maximizing dose rate is implied. If ΔE is constrained so that R 10 -R 90 is within 0.5 cm of its value for a monoenergetic beam, the maximum practical dose rate based on 2D PIC is approximately 0.1 Gy min-1

  6. Intercoder Reliability of Mapping Between Pharmaceutical Dose Forms in the German Medication Plan and EDQM Standard Terms.

    Science.gov (United States)

    Sass, Julian; Becker, Kim; Ludmann, Dominik; Pantazoglou, Elisabeth; Dewenter, Heike; Thun, Sylvia

    2018-01-01

    A nationally uniform medication plan has recently been part of German legislation. The specification for the German medication plan was developed in cooperation between various stakeholders of the healthcare system. Its' goal is to enhance usability and interoperability while also providing patients and physicians with the necessary information they require for a safe and high-quality therapy. Within the research and development project named Medication Plan PLUS, the specification of the medication plan was tested and reviewed for semantic interoperability in particular. In this study, the list of pharmaceutical dose forms provided in the specification was mapped to the standard terms of the European Directorate for the Quality of Medicines & HealthCare by different coders. The level of agreement between coders was calculated using Cohen's Kappa (κ). Results show that less than half of the dose forms could be coded with EDQM standard terms. In addition to that Kappa was found to be moderate, which means rather unconvincing agreement among coders. In conclusion, there is still vast room for improvement in utilization of standardized international vocabulary and unused potential considering cross-border eHealth implementations in the future.

  7. Development and reproducibility evaluation of a Monte Carlo-based standard LINAC model for quality assurance of multi-institutional clinical trials.

    Science.gov (United States)

    Usmani, Muhammad Nauman; Takegawa, Hideki; Takashina, Masaaki; Numasaki, Hodaka; Suga, Masaki; Anetai, Yusuke; Kurosu, Keita; Koizumi, Masahiko; Teshima, Teruki

    2014-11-01

    Technical developments in radiotherapy (RT) have created a need for systematic quality assurance (QA) to ensure that clinical institutions deliver prescribed radiation doses consistent with the requirements of clinical protocols. For QA, an ideal dose verification system should be independent of the treatment-planning system (TPS). This paper describes the development and reproducibility evaluation of a Monte Carlo (MC)-based standard LINAC model as a preliminary requirement for independent verification of dose distributions. The BEAMnrc MC code is used for characterization of the 6-, 10- and 15-MV photon beams for a wide range of field sizes. The modeling of the LINAC head components is based on the specifications provided by the manufacturer. MC dose distributions are tuned to match Varian Golden Beam Data (GBD). For reproducibility evaluation, calculated beam data is compared with beam data measured at individual institutions. For all energies and field sizes, the MC and GBD agreed to within 1.0% for percentage depth doses (PDDs), 1.5% for beam profiles and 1.2% for total scatter factors (Scps.). Reproducibility evaluation showed that the maximum average local differences were 1.3% and 2.5% for PDDs and beam profiles, respectively. MC and institutions' mean Scps agreed to within 2.0%. An MC-based standard LINAC model developed to independently verify dose distributions for QA of multi-institutional clinical trials and routine clinical practice has proven to be highly accurate and reproducible and can thus help ensure that prescribed doses delivered are consistent with the requirements of clinical protocols. © The Author 2014. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

  8. Clinical Image Evaluation of Film Mammograms in Korea: Comparison with the ACR Standard

    International Nuclear Information System (INIS)

    Gwak, Yeon Joo; Kim, Hye Jung; Kwak, Jin Young; Son, Eun Ju; Ko, Kyung Hee; Lee, Jin Hwa; Lim, Hyo Soon; Lee, You Jin; Park, Ji Won; Shin, Kyung Min; Jang, Yun-Jin

    2013-01-01

    The goal of this study is to compare the overall quality of film mammograms taken according to the Korean standards with the American College of Radiology (ACR) standard for clinical image evaluation and to identify means of improving mammography quality in Korea. Four hundred and sixty eight sets of film mammograms were evaluated with respect to the Korean and ACR standards for clinical image evaluation. The pass and failure rates of mammograms were compared by medical facility types. Average scores in each category of the two standards were evaluated. Receiver operating characteristic curve analysis was used to identify an optimal Korean standard pass mark by taking the ACR standard as the reference standard. 93.6% (438/468) of mammograms passed the Korean standard, whereas only 80.1% (375/468) passed the ACR standard (p < 0.001). Non-radiologic private clinics had the lowest pass rate (88.1%: Korean standard, 71.8%: ACR standard) and the lowest total score (76.0) by the Korean standard. Average scores of positioning were lowest (19.3/29 by the Korean standard and 3.7/5 by the ACR standard). A cutoff score of 77.0 for the Korean standard was found to correspond to a pass level when the ACR standard was applied. We suggest that tighter regulations, such as, raising the Korean pass mark, subtracting more for severe deficiencies, or considering a very low scores in even a single category as failure, are needed to improve the quality of mammography in Korea

  9. Experimental and clinical standards, and evolution of lasers in neurosurgery.

    Science.gov (United States)

    Devaux, B C; Roux, F X

    1996-01-01

    From initial experiments of ruby, argon and CO2 lasers on the nervous system so far, dramatic progress was made in delivery systems technology as well as in knowledge of laser-tissue interaction effects and hazards through various animal experiments and clinical experience. Most surgical effects of laser light on neural tissue and the central nervous system (CNS) are thermal lesions. Haemostasis, cutting and vaporization depend on laser emission parameters--wavelength, fluence and mode--and on the exposed tissues optical and thermal properties--water and haemoglobin content, thermal conductivity and specific heat. CO2 and Nd-YAG lasers have today a large place in the neurosurgical armamentarium, while new laser sources such as high power diode lasers will have one in the near future. Current applications of these lasers derive from their respective characteristics, and include CNS tumour and vascular malformation surgery, and stereotactic neurosurgery. Intracranial, spinal cord and intra-orbital meningiomas are the best lesions for laser use for haemostasis, dissection and tissue vaporization. Resection of acoustic neuromas, pituitary tumours, spinal cord neuromas, intracerebral gliomas and metastases may also benefit from lasers as accurate, haemostatic, non-contact instruments which reduce surgical trauma to the brain and eloquent structures such as brain stem and cranial nerves. Coagulative lasers (1.06 microns and 1.32 microns Nd-YAG, argon, or diode laser) will find an application for arteriovenous malformations and cavernomas. Any fiberoptic-guided laser will find a use during stereotactic neurosurgical procedures, including image-guided resection of tumours and vascular malformations and endoscopic tumour resection and cysts or entry into a ventricle. Besides these routine applications of lasers, laser interstitial thermotherapy (LITT) and photodynamic therapy (PDT) of brain tumours are still in the experimental stage. The choice of a laser in a

  10. Dose-response effects of cognitive-behavioral insomnia therapy: a randomized clinical trial.

    Science.gov (United States)

    Edinger, Jack D; Wohlgemuth, William K; Radtke, Rodney A; Coffman, Cynthia J; Carney, Colleen E

    2007-02-01

    To determine the optimal number of therapist-guided Cognitive-Behavioral Insomnia Therapy (CBT) sessions required for treating primary sleep-maintenance insomnia. Randomized, parallel-group, clinical trial at a single academic medical center. Outpatient treatment lasted 8 weeks with final follow-up conducted at 6 months. 86 adults (43 women; mean age 55.4 +/- 9.7 years) with primary sleep-maintenance insomnia (nightly mean wake time after sleep onset [WASO] = 93.4 +/- 44.5 minutes). One (week 1), 2 (weeks 1 and 5), 4 (biweekly), or 8 (weekly) individual CBT sessions scheduled over an 8-week treatment phase, compared with an 8-week no-treatment waiting period (WL). Sleep diary and actigraphy measures of total sleep time, onset latency, WASO, total wake time, and sleep efficiency, as well as questionnaire measures of global insomnia symptoms, sleep related self-efficacy, and mood. Statistical tests of subjective/objective sleep measures favored the 1- and 4-session CBT doses over the other CBT doses and WL control. However, comparisons of pretreatment data with data acquired at the 6-month follow-up showed only the 4-session group showed significant long-term improvements in objective wake time and sleep efficiency measures. Additionally, 58.3% of the patients receiving 4 CBT sessions met criteria for clinically significant improvement by the end of treatment compared to 43.8% of those receiving 1 CBT session, 22.2% of those provided 2 sessions, 35.3% of those receiving 8 sessions, and 9.1% of those in the control condition. Findings suggest that 4 individual, biweekly sessions represents the optimal dosing for the CBT intervention tested. Additional dose-response studies are warranted to test CBT models that contain additional treatment components or are delivered via group therapy.

  11. Contamination and cancers: low-dose risks and standards of radioprotection

    International Nuclear Information System (INIS)

    Vignes, S.

    1980-01-01

    Irradiation of the population due to the running of nuclear power stations represents less than 1% of the natural radioactivity today, and should amount to 3% at most by the year 2 000. The main effects of ionizing radiations are reviewed and their undetectability below 100 rems is underlined. Thus the evaluation of low-dose risks can only be speculative and the cautions hypothesis adopted is that of a linear relationship between dose and effect, together with the absence of threshold. According to calculations the worker, supposedly exposed to 500 mrem a year between ages 18 and 65, would run a 22.2% instead of the normal 22% risk of dying of cancer. As for the population, the risk would increase by only 1 per 10 000 in the year 2 000. This means that no other mutagenic and carcinogenic agent is as well regulated as radioactive pollution and efforts directed at a better control of harmful chemicals, for instance, are only taking an example from the ruling on radioprotection [fr

  12. The FLUKA Monte Carlo code coupled with the NIRS approach for clinical dose calculations in carbon ion therapy

    Science.gov (United States)

    Magro, G.; Dahle, T. J.; Molinelli, S.; Ciocca, M.; Fossati, P.; Ferrari, A.; Inaniwa, T.; Matsufuji, N.; Ytre-Hauge, K. S.; Mairani, A.

    2017-05-01

    Particle therapy facilities often require Monte Carlo (MC) simulations to overcome intrinsic limitations of analytical treatment planning systems (TPS) related to the description of the mixed radiation field and beam interaction with tissue inhomogeneities. Some of these uncertainties may affect the computation of effective dose distributions; therefore, particle therapy dedicated MC codes should provide both absorbed and biological doses. Two biophysical models are currently applied clinically in particle therapy: the local effect model (LEM) and the microdosimetric kinetic model (MKM). In this paper, we describe the coupling of the NIRS (National Institute for Radiological Sciences, Japan) clinical dose to the FLUKA MC code. We moved from the implementation of the model itself to its application in clinical cases, according to the NIRS approach, where a scaling factor is introduced to rescale the (carbon-equivalent) biological dose to a clinical dose level. A high level of agreement was found with published data by exploring a range of values for the MKM input parameters, while some differences were registered in forward recalculations of NIRS patient plans, mainly attributable to differences with the analytical TPS dose engine (taken as reference) in describing the mixed radiation field (lateral spread and fragmentation). We presented a tool which is being used at the Italian National Center for Oncological Hadrontherapy to support the comparison study between the NIRS clinical dose level and the LEM dose specification.

  13. Clinical results of iridium-192 high dose rate brachytherapy with external beam radiotherapy

    International Nuclear Information System (INIS)

    Nohara, Takahiro; Mizokami, Atsushi; Kumano, Tomoyasu

    2010-01-01

    Here, we report the clinical results of iridium-192 high dose rate brachytherapy at Kanazawa University Hospital. The study population consisted of 166 patients diagnosed with T1c-T3bN0M0 prostate cancer treated with high dose rate brachytherapy and external beam radiotherapy and followed up for 6 months or longer. Treatment consisted of external beam radiotherapy to the prostate at 44 Gy/22 fractions and high dose rate brachytherapy at 18 Gy/3 fractions. Median follow-up interval was 31.5 months (range 6.2-88.7). The overall 5-year biological recurrence-free survival rate was 93.0%. The 5-year biological recurrence-free survival rates for the patients in low-, intermediate- and high-risk groups according to the D'Amico risk classification criteria were 96.1%, 89.0% and 91.6%, respectively. When limited to the group that did not receive adjuvant hormonal therapy, the 5-year biological recurrence-free survival rates for the patients in low-, intermediate- and high-risk groups were 96.0%, 96.3% and 82.9%, respectively. Grade 3 or greater adverse effects were rare. Urethral stricture was observed in only 1.0% of the patients. Eighty percent of patients retained erectile function after high dose rate brachytherapy and reported satisfaction with sexual function. High dose rate brachytherapy is considered a good form of treatment for localized prostate cancer, although longer follow-up is necessary. (author)

  14. Chest CT using spectral filtration: radiation dose, image quality, and spectrum of clinical utility

    Energy Technology Data Exchange (ETDEWEB)

    Braun, Franziska M.; Johnson, Thorsten R.C.; Sommer, Wieland H.; Thierfelder, Kolja M.; Meinel, Felix G. [University Hospital Munich, Institute for Clinical Radiology, Munich (Germany)

    2015-06-01

    To determine the radiation dose, image quality, and clinical utility of non-enhanced chest CT with spectral filtration. We retrospectively analysed 25 non-contrast chest CT examinations acquired with spectral filtration (tin-filtered Sn100 kVp spectrum) compared to 25 examinations acquired without spectral filtration (120 kV). Radiation metrics were compared. Image noise was measured. Contrast-to-noise-ratio (CNR) and figure-of-merit (FOM) were calculated. Diagnostic confidence for the assessment of various thoracic pathologies was rated by two independent readers. Effective chest diameters were comparable between groups (P = 0.613). In spectral filtration CT, median CTDI{sub vol}, DLP, and size-specific dose estimate (SSDE) were reduced (0.46 vs. 4.3 mGy, 16 vs. 141 mGy*cm, and 0.65 vs. 5.9 mGy, all P < 0.001). Spectral filtration CT had higher image noise (21.3 vs. 13.2 HU, P < 0.001) and lower CNR (47.2 vs. 75.3, P < 0.001), but was more dose-efficient (FOM 10,659 vs. 2,231/mSv, P < 0.001). Diagnostic confidence for parenchymal lung disease and osseous pathologies was lower with spectral filtration CT, but no significant difference was found for pleural pathologies, pulmonary nodules, or pneumonia. Non-contrast chest CT using spectral filtration appears to be sufficient for the assessment of a considerable spectrum of thoracic pathologies, while providing superior dose efficiency, allowing for substantial radiation dose reduction. (orig.)

  15. Prophylactic effect of low dose vitamin D in osteopenia of prematurity: a clinical trial study.

    Directory of Open Access Journals (Sweden)

    Paymaneh Alizadeh Taheri

    2014-09-01

    Full Text Available Osteopenia of prematurity (OOP is a preventable disease. Improved survival of premature newborns is associated with an increased incidence of OOP. The purpose of this study was to compare the prophylactic effects of two low doses of vitamin D (200 and 400 IU/Day on the clinical, biochemical and radiological indices of the rickets of prematurity. In a randomized clinical trial, 60 preterm newborns with birth weight < 2000 g & gestational age < 37 weeks were randomly divided in two groups. Thirty newborns received 200 IU/d of vitamin D in group one and 30 ones received 400 IU/day of vitamin D in group two. On the 6th to 8th weeks of life, serum calcium, phosphate, alkaline phosphates, and 25-hydroxy vitamin D concentrations were measured and x- ray of left wrist and physical examination were performed. Both groups had no difference in biochemical, radiological or clinical presentation of rickets. Current study indicated that low dose vitamin D (200 IU/Day is enough for prevention of OOP.

  16. Best Practices in Stability Indicating Method Development and Validation for Non-clinical Dose Formulations.

    Science.gov (United States)

    Henry, Teresa R; Penn, Lara D; Conerty, Jason R; Wright, Francesca E; Gorman, Gregory; Pack, Brian W

    2016-11-01

    Non-clinical dose formulations (also known as pre-clinical or GLP formulations) play a key role in early drug development. These formulations are used to introduce active pharmaceutical ingredients (APIs) into test organisms for both pharmacokinetic and toxicological studies. Since these studies are ultimately used to support dose and safety ranges in human studies, it is important to understand not only the concentration and PK/PD of the active ingredient but also to generate safety data for likely process impurities and degradation products of the active ingredient. As such, many in the industry have chosen to develop and validate methods which can accurately detect and quantify the active ingredient along with impurities and degradation products. Such methods often provide trendable results which are predictive of stability, thus leading to the name; stability indicating methods. This document provides an overview of best practices for those choosing to include development and validation of such methods as part of their non-clinical drug development program. This document is intended to support teams who are either new to stability indicating method development and validation or who are less familiar with the requirements of validation due to their position within the product development life cycle.

  17. Relationship between kidney burden and radiation dose from chronic ingestion of U: Implications for radiation standards for the public

    International Nuclear Information System (INIS)

    Kocher, D.C.

    1989-01-01

    Metabolic models for U in adults recommended by Wrenn et al. (1985) and the International Commission on Radiological Protection (ICRP 1979a) were used to study the relationship between kidney burden and radiation dose from chronic ingestion of soluble 238U or natural U and whether current radiation standards for the public provide adequate protection against chemical toxicity from U in the kidney. We assumed that the threshold concentration for chemical toxicity is 1 microgram of U g-1 of kidney and that a safety factor of 10 should be applied in limiting kidney burdens for maximally exposed individuals in the general public. We found that a limit on annual effective dose equivalent of 1 mSv (0.1 rem) for chronic exposures of the public from all sources, as recommended by the ICRP (1985) and the National Council on Radiation Protection and Measurements (NCRP 1987), corresponds to concentrations of U in the kidney from chronic ingestion that exceed the assumed threshold for chemical toxicity of 1 microgram g-1 only for 238U using the metabolic model of the ICRP (1979a). However, using either metabolic model (ICRP 1979a; Wrenn et al. 1985), the predicted concentrations of U in the kidney exceeded the limit of 0.1 microgram g-1, based on the assumed safety factor for protection of the public, for both 238U and natural U. From these results, we concluded that chemical toxicity should be considered in developing health protection standards for the public for ingestion of soluble 238U or natural U. Environmental radiation standards for certain practices established by the U.S. Environmental Protection Agency and Nuclear Regulatory Commission (EPA 1987a, 1987b, 1987c, 1987d; NRC 1988a) are consistent with a limit on annual effective dose equivalent of 0.25 mSv (25 mrem) per practice. If the metabolic model of Wrenn et al. 27 references

  18. Assessment of image quality of a standard and two dose-reducing protocols in paediatric pelvic CT

    Energy Technology Data Exchange (ETDEWEB)

    Ratcliffe, John; Frawley, Kieran; Coakley, Kerry; Cloake, John [Department of Radiology, The Royal Children' s Hospital, Brisbane, Queensland (Australia); Swanson, Cheryl E. [Department of Surgery, University of Queensland (Australia); Hafiz, Niru [Department of Child Health, The Royal Children' s Hospital, Brisbane (Australia)

    2003-03-01

    Concerns exist regarding the effect of radiation dose from paediatric pelvic CT scans and the potential later risk of radiation-induced neoplasm and teratogenic outcomes in these patients. To assess the diagnostic quality of CT images of the paediatric pelvis using either reduced mAs or increased pitch compared with standard settings. A prospective study of pelvic CT scans of 105 paediatric patients was performed using one of three protocols: (1) 31 at a standard protocol of 200 mA with rotation time of 0.75 s at 120 kVp and a pitch factor approximating 1.4; (2) 31 at increased pitch factor approaching 2 and 200 mA; and (3) 43 at a reduced setting of 100 mA and a pitch factor of 1.4. All other settings remained the same in all three groups. Image quality was assessed by radiologists blinded to the protocol used in each scan. No significant difference was found between the quality of images acquired at standard settings and those acquired at half the standard mAs. The use of increased pitch factor resulted in a higher proportion of poor images. Images acquired at 120 kVp using 75 mAs are equivalent in diagnostic quality to those acquired at 150 mAs. Reduced settings can provide useful imaging of the paediatric pelvis and should be considered as a standard protocol in these situations. (orig.)

  19. Measurement of psychological state changes at low dopamine transporter occupancy following a clinical dose of mazindol.

    Science.gov (United States)

    Kimura, Y; Maeda, J; Yamada, M; Takahata, K; Yokokawa, K; Ikoma, Y; Seki, C; Ito, H; Higuchi, M; Suhara, T

    2017-02-01

    The beneficial effects of psychostimulant drugs in the treatment of psychiatric disorders occur because they increase the extracellular dopamine concentration by inhibiting re-uptake of extracellular dopamine at dopamine transporters. However, the psychological effects at low dopamine transporter occupancy have not been well demonstrated. The purpose of the study was to evaluate the psychological effects, dopamine transporter occupancy, and dopamine release induced by a single oral administration of a clinical dose of mazindol. Ten healthy male volunteers were orally administered a placebo and a clinical dose of mazindol (1.5 mg) on separate days. The psychological effects of mazindol were assessed using a visual analogue scale to detect alterations in the state of consciousness. The amount of blockade of dopamine transporters was assessed using positron emission tomography with [ 18 F]FE-PE2I and extracellular dopamine release was measured as the amount of change in [ 11 C]raclopride binding. Following administration of a clinical dose of mazindol, the dopamine transporters were blocked by 24-25 %, and the binding potential of [ 11 C]raclopride was reduced by 2.8-4.6 %. The differences of a score measuring derealisation and depersonalization associated with a positive basic mood were significantly correlated with the change in the [ 11 C]raclopride binding in the limbic striatum. A subtle alteration in the state of consciousness was detected with a correlation to the changes in the [ 11 C]raclopride binding, which implies that a subtle alteration in extracellular dopamine concentration in the limbic striatum by a small amount of dopamine transporter occupancy can affect the state of consciousness. TRIAL REGISTRATION HTTPS://UPLOAD.UMIN.AC.JP/CGI-OPEN-BIN/CTR_E/CTR_VIEW.CGI?RECPTNO=R000009703 : UMIN000008232.

  20. Standardizing clinical trials workflow representation in UML for international site comparison.

    Science.gov (United States)

    de Carvalho, Elias Cesar Araujo; Jayanti, Madhav Kishore; Batilana, Adelia Portero; Kozan, Andreia M O; Rodrigues, Maria J; Shah, Jatin; Loures, Marco R; Patil, Sunita; Payne, Philip; Pietrobon, Ricardo

    2010-11-09

    With the globalization of clinical trials, a growing emphasis has been placed on the standardization of the workflow in order to ensure the reproducibility and reliability of the overall trial. Despite the importance of workflow evaluation, to our knowledge no previous studies have attempted to adapt existing modeling languages to standardize the representation of clinical trials. Unified Modeling Language (UML) is a computational language that can be used to model operational workflow, and a UML profile can be developed to standardize UML models within a given domain. This paper's objective is to develop a UML profile to extend the UML Activity Diagram schema into the clinical trials domain, defining a standard representation for clinical trial workflow diagrams in UML. Two Brazilian clinical trial sites in rheumatology and oncology were examined to model their workflow and collect time-motion data. UML modeling was conducted in Eclipse, and a UML profile was developed to incorporate information used in discrete event simulation software. Ethnographic observation revealed bottlenecks in workflow: these included tasks requiring full commitment of CRCs, transferring notes from paper to computers, deviations from standard operating procedures, and conflicts between different IT systems. Time-motion analysis revealed that nurses' activities took up the most time in the workflow and contained a high frequency of shorter duration activities. Administrative assistants performed more activities near the beginning and end of the workflow. Overall, clinical trial tasks had a greater frequency than clinic routines or other general activities. This paper describes a method for modeling clinical trial workflow in UML and standardizing these workflow diagrams through a UML profile. In the increasingly global environment of clinical trials, the standardization of workflow modeling is a necessary precursor to conducting a comparative analysis of international clinical trials

  1. Standardizing data exchange for clinical research protocols and case report forms: An assessment of the suitability of the Clinical Data Interchange Standards Consortium (CDISC) Operational Data Model (ODM)

    Science.gov (United States)

    Huser, Vojtech; Sastry, Chandan; Breymaier, Matthew; Idriss, Asma; Cimino, James J.

    2015-01-01

    Efficient communication of a clinical study protocol and case report forms during all stages of a human clinical study is important for many stakeholders. An electronic and structured study representation format that can be used throughout the whole study life-span can improve such communication and potentially lower total study costs. The most relevant standard for representing clinical study data, applicable to unregulated as well as regulated studies, is the Operational Data Model (ODM) in development since 1999 by the Clinical Data Interchange Standards Consortium (CDISC). ODM's initial objective was exchange of case report forms data but it is increasingly utilized in other contexts. An ODM extension called Study Design Model, introduced in 2011, provides additional protocol representation elements. Using a case study approach, we evaluated ODM's ability to capture all necessary protocol elements during a complete clinical study lifecycle in the Intramural Research Program of the National Institutes of Health. ODM offers the advantage of a single format for institutions that deal with hundreds or thousands of concurrent clinical studies and maintain a data warehouse for these studies. For each study stage, we present a list of gaps in the ODM standard and identify necessary vendor or institutional extensions that can compensate for such gaps. The current version of ODM (1.3.2) has only partial support for study protocol and study registration data mainly because it is outside the original development goal. ODM provides comprehensive support for representation of case report forms (in both the design stage and with patient level data). Inclusion of requirements of observational, non-regulated or investigator-initiated studies (outside Food and Drug Administration (FDA) regulation) can further improve future revisions of the standard. PMID:26188274

  2. Standardizing data exchange for clinical research protocols and case report forms: An assessment of the suitability of the Clinical Data Interchange Standards Consortium (CDISC) Operational Data Model (ODM).

    Science.gov (United States)

    Huser, Vojtech; Sastry, Chandan; Breymaier, Matthew; Idriss, Asma; Cimino, James J

    2015-10-01

    Efficient communication of a clinical study protocol and case report forms during all stages of a human clinical study is important for many stakeholders. An electronic and structured study representation format that can be used throughout the whole study life-span can improve such communication and potentially lower total study costs. The most relevant standard for representing clinical study data, applicable to unregulated as well as regulated studies, is the Operational Data Model (ODM) in development since 1999 by the Clinical Data Interchange Standards Consortium (CDISC). ODM's initial objective was exchange of case report forms data but it is increasingly utilized in other contexts. An ODM extension called Study Design Model, introduced in 2011, provides additional protocol representation elements. Using a case study approach, we evaluated ODM's ability to capture all necessary protocol elements during a complete clinical study lifecycle in the Intramural Research Program of the National Institutes of Health. ODM offers the advantage of a single format for institutions that deal with hundreds or thousands of concurrent clinical studies and maintain a data warehouse for these studies. For each study stage, we present a list of gaps in the ODM standard and identify necessary vendor or institutional extensions that can compensate for such gaps. The current version of ODM (1.3.2) has only partial support for study protocol and study registration data mainly because it is outside the original development goal. ODM provides comprehensive support for representation of case report forms (in both the design stage and with patient level data). Inclusion of requirements of observational, non-regulated or investigator-initiated studies (outside Food and Drug Administration (FDA) regulation) can further improve future revisions of the standard. Published by Elsevier Inc.

  3. Intra-patient comparison of reduced-dose model-based iterative reconstruction with standard-dose adaptive statistical iterative reconstruction in the CT diagnosis and follow-up of urolithiasis

    Energy Technology Data Exchange (ETDEWEB)

    Tenant, Sean; Pang, Chun Lap; Dissanayake, Prageeth [Peninsula Radiology Academy, Plymouth (United Kingdom); Vardhanabhuti, Varut [Plymouth University Peninsula Schools of Medicine and Dentistry, Plymouth (United Kingdom); University of Hong Kong, Department of Diagnostic Radiology, Li Ka Shing Faculty of Medicine, Pokfulam (China); Stuckey, Colin; Gutteridge, Catherine [Plymouth Hospitals NHS Trust, Plymouth (United Kingdom); Hyde, Christopher [University of Exeter Medical School, St Luke' s Campus, Exeter (United Kingdom); Roobottom, Carl [Plymouth University Peninsula Schools of Medicine and Dentistry, Plymouth (United Kingdom); Plymouth Hospitals NHS Trust, Plymouth (United Kingdom)

    2017-10-15

    To evaluate the accuracy of reduced-dose CT scans reconstructed using a new generation of model-based iterative reconstruction (MBIR) in the imaging of urinary tract stone disease, compared with a standard-dose CT using 30% adaptive statistical iterative reconstruction. This single-institution prospective study recruited 125 patients presenting either with acute renal colic or for follow-up of known urinary tract stones. They underwent two immediately consecutive scans, one at standard dose settings and one at the lowest dose (highest noise index) the scanner would allow. The reduced-dose scans were reconstructed using both ASIR 30% and MBIR algorithms and reviewed independently by two radiologists. Objective and subjective image quality measures as well as diagnostic data were obtained. The reduced-dose MBIR scan was 100% concordant with the reference standard for the assessment of ureteric stones. It was extremely accurate at identifying calculi of 3 mm and above. The algorithm allowed a dose reduction of 58% without any loss of scan quality. A reduced-dose CT scan using MBIR is accurate in acute imaging for renal colic symptoms and for urolithiasis follow-up and allows a significant reduction in dose. (orig.)

  4. Study of the therapeutic dose and the clinical effect on Graves' disease with I-131 treatment

    International Nuclear Information System (INIS)

    Dang, Y.

    2005-01-01

    Full text: Graves' disease is being treated with I-131 for more than 40 years in China. Previously the dose of I-131 used to be calculated using the 'Quimby' formula. We have now observed that the dose of I-131 administered to patients is now lower in recent years than the early years. The radioactive iodine uptake by the thyroid gland has also changed significantly over a period of time. In this paper we intend to explore these reasons and to research the relationship between the dose and the effect as well as the main cause of the incidence of the hypothyroidism. The parameters in 'Quimby' formula including I-131 uptake, effective half-life and thyroid weight were analyzed and compared with each year data from 1961 to 1988 and subjected to multiple regression analysis to determine the influence on the calculation of dose in 4465 patients. The therapeutic effects were compared with the data of the clinical follow-up of patients between 1961-1973 and 1978-1988 in 748 patients. The factors which might lead to the hypothyroidism were investigated with the non-condition logistic regression. The I-131 uptake was repeatedly measured within one week in 100 patients to identify the changing pattern of the I-131 uptake and its influence on the administered therapeutic dose. We observed an increase in the value of I-131 uptake. The value of I-131 uptake showed an increase after 1977, as well as a prolongation of effective half-life after 1973. The main reason for these changes being a replacement of the equipment in 1977 (G-M counter tube was replaced by scintillation counter), and the other reason being salt iodization in China in 1973. These two factors resulted in a significant reduction in the administered dose of I-131 during the period 1974-1988 as compared to the previous period 1961-1973; the mean administered doses being 168.35MBq and 330.33MBq respectively. The result of multiple regression analyses suggested that the thyroid weight and the effective half

  5. Standardizing Clinical Document Names Using the HL7/LOINC Document Ontology and LOINC Codes.

    Science.gov (United States)

    Chen, Elizabeth S; Melton, Genevieve B; Engelstad, Mark E; Sarkar, Indra Neil

    2010-11-13

    The standardization of clinical document names is an essential first step towards the optimal use, management, and exchange of documents within and across institutions. The HL7/LOINC Document Ontology (DO) is an existing and evolving document standard developed to provide consistent naming of clinical documents and to guide the creation of LOINC codes for clinical notes. The goal of this study was to explore the feasibility and challenges of mapping local clinical document names from two institutions into the five axes of the DO and then to leverage this mapping for identifying specific LOINC codes. The results indicate that the DO is either adequate or too broad for representing a majority of the document names and that there are LOINC codes available for one- to two-thirds of the names. Through this mapping process, granularity and other issues were revealed that will be valuable for guiding next steps towards effective standardization of clinical document names.

  6. Dose coefficients and derived guidance and clinical decision levels for contaminated wounds

    Energy Technology Data Exchange (ETDEWEB)

    Bertelli, Luiz [Los Alamos National Laboratory; Toohey, Richard E [ORISE/ORAU; Sugarman, Steven A [ORISE/ORAU; Christensen, Doran R [ORISE/ORAU

    2009-01-01

    The NCRP Wound Model describing the retention of selected radionuclides at the site of a contaminated wound and their uptake into the transfer compartment has been combined with the ICRP element-specific systemic models for those radionuclides to derive dose coefficients for intakes via contaminated wounds. Those coefficients have been used to generate derived guidance levels (i.e., the activity in a wound that would result in an effective dose of 20 or 50 mSv, or in some cases, a committed organ equivalent dose of 500 mSv), and clinical decision levels (i.e., activity levels that would indicate the need for consideration of medical intervention to remove activity from the wound site or administration of decorporation therapy or both), typically set at 5 times the derived guidance levels. Data are provided for the radionuclides commonly encountered at nuclear power plants and nuclear weapons, fuel fabrication or recycling, waste disposal, medical and research facilities. These include: {sup 60}Co, {sup 90}Sr, {sup 99m}Tc, {sup 131}I, {sup 137}Cs, {sup 192}Ir, {sup 210}Po, {sup 226,228}Ra, {sup 228,232}Th, {sup 235,238}U, {sup 237}Np, {sup 238,239}Pu, {sup 241}Am, {sup 242,244}Cm, and {sup 252}Cf.

  7. Selective fallopian tube catheterisation in female infertility: clinical results and absorbed radiation dose

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, K. [Department of Radiology, Nagoya University School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466 (Japan); Ishiguchi, T. [Department of Radiology, Nagoya University School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466 (Japan); Maekoshi, H. [Department of Radiological Technology, Nagoya University College of Medical Technology, Nagoya (Japan); Ando, Y. [Department of Radiology, Nagoya University School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466 (Japan); Tsuzaka, M. [Department of Radiological Technology, Nagoya University College of Medical Technology, Nagoya (Japan); Tamiya, T. [Department of Radiological Technology, Nagoya University College of Medical Technology, Nagoya (Japan); Suganuma, N. [Department of Obstetrics and Gynecology, Branch Hospital, Nagoya University School of Medicine, Nagoya (Japan); Ishigaki, T. [Department of Radiology, Nagoya University School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466 (Japan)

    1996-08-01

    Clinical results of fluoroscopic fallopian tube catheterisation and absorbed radiation doses during the procedure were evaluated in 30 infertility patients with unilateral or bilateral tubal obstruction documented on hysterosalpingography. The staged technique consisted of contrast injection through an intrauterine catheter with a vacuum cup device, ostial salpingography with the wedged catheter, and selective salpingography with a coaxial microcatheter. Of 45 fallopian tubes examined, 35 (78 %) were demonstrated by the procedure, and at least one tube was newly demonstrated in 26 patients (87 %). Six of these patients conceived spontaneously in the follow-up period of 1-11 months. Four pregnancies were intrauterine and 2 were ectopic. This technique provided accurate and detailed information in the diagnosis and treatment of tubal obstruction in infertility patients. The absorbed radiation dose to the ovary in the average standardised procedure was estimated to be 0.9 cGy. Further improvement in the X-ray equipment and technique is required to reduce the radiation dose. (orig.). With 3 figs., 3 tabs.

  8. Three dimensional dose verification for clinical treatments of small intracranial tumours

    International Nuclear Information System (INIS)

    Taylor, M.L.; Dunn, L.; Kairn, L.; Jenny, J.; Knight, R.; Trapp, J.; Smith, R.; Ackerly, T.

    2010-01-01

    Full text: Cancers of the brain and central nervous system account for 1.6% of new cancers and 1.8% of cancer deaths globally. The highest rates of all developed nations are observed in Australia and New Zealand. There are known complexities associated with dose measurement of very small radiation fields. Here, 3D dosimetric verification of treatments for small intracranial tumours using gel dosimetry was investigated. An anthropomorphic head phantom with a 43 mm diameter and 63 mm long gel container was filled with PAGAT normoxic radiosensitive gel. In this work, we show results for a 12-field stereotactic radiotherapy treatment delivered using a Varian 21EX with BrainLAB mini-multi leaf collimator. The gel was read out using an Octopus-1Q laser optical CT scanner. Generally good agreement was observed between the measured doses and those calculated with the iPlan treatment planning system (pencil beam convolution); see Fig. I. For gamma criteria of 5%/5 mm the percentage of gamma values less than unity was 95% above the 80% isodose line, indicating good PTV coverage. For lower isodose regions approaching the boundaries of the container poorer agreement was observed. The feasibility of three-dimensional measurement of small field dose distributions in clinical contexts has been demonstrated. Development of this methodology has the potential to overcome many shortcomings of other dosimetric methods, such as limitations of spatial information (typically one- and two-dimensions), volume-averaging effects and perturbation due to poor mediamatching. (author)

  9. The Performance of Standardized Patients in Portraying Clinical Scenarios in Speech-Language Therapy

    Science.gov (United States)

    Hill, Anne E.; Davidson, Bronwyn J.; Theodoros, Deborah G.

    2013-01-01

    Background: Standardized patients (SPs) are frequently included in the clinical preparation of students in the health sciences. An acknowledged benefit of using SPs is the opportunity to provide a standardized method by which students can demonstrate and develop their competency. Relatively little is known, however, about the capacity of SPs to…

  10. The Electronic Patient Record and Second Generation Clinical Databases: Problems of Standards and Nomenclature.

    Science.gov (United States)

    Monteith, Brian D.

    1991-01-01

    Three principles of classification are stressed in the development of electronic dental patient records and clinical databases: (1) the classification must have a suitable organizing principle; (2) use must be made of standard terminology; and (3) there must be standard operational criteria. (DB)

  11. Clinical Pharmacokinetics of Levornidazole in Elderly Subjects and Dosing Regimen Evaluation Using Pharmacokinetic/Pharmacodynamic Analysis.

    Science.gov (United States)

    Guo, Beining; He, Gaoli; Wu, Xiaojie; Yu, Jicheng; Cao, Guoying; Li, Yi; Fan, Yaxin; Chen, Yuancheng; Shi, Yaoguo; Zhang, Yingyuan; Zhang, Jing

    2017-07-01

    Levornidazole, the levo-isomer of ornidazole, is a third-generation nitroimidazole derivative newly developed after metronidazole, tinidazole, and ornidazole. An open-label, parallel-controlled, single-dose study was conducted for the investigation of the pharmacokinetic (PK) profile of levornidazole and its metabolites in healthy elderly Chinese subjects, and for the evaluation of 2 dosing regimens in the elderly. Levornidazole was intravenously administered at 500 mg to healthy elderly (aged 60-80 years) or young subjects (aged 19-45 years). The PK profiles of levornidazole and its metabolites in elderly subjects were evaluated and compared with those in the young group. WinNonlin software was used for simulating the PK profile of levornidazole in the elderly population following the dosing regimens of 500 mg BID and 750 mg once daily for 7 days. Monte Carlo simulation was used for estimating the cumulative fraction of response and probability of target attainment of both dosing regimens against Bacteroides spp. The C max , AUC 0-24, and AUC 0-∞ values of levornidazole in the elderly group were 11.98 μg/mL, 131.36 μg·h/mL, and 173.61 μg·h/mL, respectively. The t 1/2 , CL t , and mean residence time from time 0 to infinity were 12.21 hours, 2.91 L/h, and 16.46 hours. The metabolic ratios of metabolites (M) 1, 2, 4, and 6 were 90% against B fragilis and other Bacteroides spp, and the probability of target attainment was >90% when the minimum inhibitory concentration was ≤1 μg/mL, in both groups. No dosing regimen adjustment is suggested when levornidazole is used in elderly patients with normal hepatic functioning and mild renal dysfunction. The findings from the PK/PD analysis imply that both regimens may achieve satisfactory clinical and microbiological efficacy against anaerobic infections in elderly patients. Chinese Clinical Trial Registry (http://www.chictr.org.cn) identifier: ChiCTR-OPC-16007938. Copyright © 2017 Elsevier HS Journals, Inc. All

  12. Clinical Outcomes With Dose-Escalated Adaptive Radiation Therapy for Urinary Bladder Cancer: A Prospective Study

    International Nuclear Information System (INIS)

    Murthy, Vedang; Masodkar, Renuka; Kalyani, Nikhil; Mahantshetty, Umesh; Bakshi, Ganesh; Prakash, Gagan; Joshi, Amit; Prabhash, Kumar; Ghonge, Sujata; Shrivastava, Shyamkishore

    2016-01-01

    Purpose: The purpose of this study was to assess feasibility, clinical outcomes, and toxicity in patients with bladder cancer treated with adaptive, image guided radiation therapy (IGRT) for bladder preservation as a part of trimodality treatment. The role of dose escalation was also studied. Methods and Materials: Forty-four patients with localized bladder cancer were enrolled in a prospective study. They underwent maximal safe resection of bladder tumor and concurrent platinum-based chemotherapy. Patients with large tumors were offered induction chemotherapy. Radiation therapy planning was done using either 3 (n=34) or 6 (n=10) concentrically grown planning target volumes (PTV). Patients received 64 Gy in 32 fractions to the whole bladder and 55 Gy to the pelvic nodes and, if appropriate, a simultaneous integrated boost to the tumor bed to 68 Gy (equivalent dose for 2-Gy fractions assuming α/β of 10 [EQD2] 10  = 68.7 Gy). Daily megavoltage (MV) imaging helped to choose the most appropriate PTV encompassing bladder for the particular day (using plan-of-the-day approach). Results: Most patients (88%) had T2 disease. Sixteen patients (36%) received neoadjuvant chemotherapy. A majority of the patients (73%) received prophylactic nodal irradiation, whereas 55% of the patients received escalated dose to the tumor bed. With a median follow-up of 30 months, the 3-year locoregional control (LRC), disease-free survival, and overall survival (OS) were 78%, 66%, and 67%, respectively. The bladder preservation rate was 83%. LRC (87% vs 68%, respectively, P=.748) and OS (74% vs 60%, respectively, P=.36) rates were better in patients receiving dose escalation. Instances of acute and late Radiation Therapy Oncology Group (RTOG) grade 3 genitourinary toxicity was seen in 5 (11%) and 2 (4%) patients, respectively. There was no acute or late RTOG grade 3 or higher gastrointestinal toxicity. Conclusions: Adaptive IGRT using plan-of-the-day approach for bladder preservation

  13. Standardization of the Fricke gel dosimetry method and tridimensional dose evaluation using the magnetic resonance imaging technique

    International Nuclear Information System (INIS)

    Cavinato, Christianne Cobello

    2009-01-01

    This study standardized the method for obtaining the Fricke gel solution developed at IPEN. The results for different gel qualities used in the preparation of solutions and the influence of the gelatin concentration in the response of dosimetric solutions were compared. Type tests such as: dose response dependence, minimum and maximum detection limits, response reproducibility, among others, were carried out using different radiation types and the Optical Absorption (OA) spectrophotometry and Magnetic Resonance (MR) techniques. The useful dose ranges for Co 60 gamma radiation and 6 MeV photons are 0,4 to 30,0 Gy and 0,5 to 100,0 Gy , using OA and MR techniques, respectively. A study of ferric ions diffusion in solution was performed to determine the optimum time interval between irradiation and samples evaluation; until 2,5 hours after irradiation to obtain sharp MR images. A spherical simulator consisting of Fricke gel solution prepared with 5% by weight 270 Bloom gelatine (national quality) was developed to be used to three-dimensional dose assessment using the Magnetic Resonance Imaging (MRI) technique. The Fricke gel solution prepared with 270 Bloom gelatine, that, in addition to low cost, can be easily acquired on the national market, presents satisfactory results on the ease of handling, sensitivity, response reproducibility and consistency. The results confirm their applicability in the three-dimensional dosimetry using MRI technique. (author)

  14. TU-AB-207A-03: Image Quality, Dose, and Clinical Applications

    Energy Technology Data Exchange (ETDEWEB)

    Dong, F. [The Cleveland Clinic (United States)

    2016-06-15

    Practicing medical physicists are often time charged with the tasks of evaluating and troubleshooting complex image quality issues related to CT scanners. This course will equip them with a solid and practical understanding of common CT imaging chain and its major components with emphasis on acquisition physics and hardware, reconstruction, artifacts, image quality, dose, and advanced clinical applications. The core objective is to explain the effects of these major system components on the image quality. This course will not focus on the rapid-changing advanced technologies given the two-hour time limit, but the fundamental principles discussed in this course may facilitate better understanding of those more complicated technologies. The course will begin with an overview of CT acquisition physics and geometry. X-ray tube and CT detector are important acquisition hardware critical to the overall image quality. Each of these two subsystems consists of several major components. An in-depth description of the function and failure modes of these components will be provided. Examples of artifacts related to these failure modes will be presented: off-focal radiation, tube arcing, heel effect, oil bubble, offset drift effect, cross-talk effect, and bad pixels. The fundamentals of CT image reconstruction will first be discussed on an intuitive level. Approaches that do not require rigorous derivation of mathematical formulations will be presented. This is followed by a detailed derivation of the Fourier slice theorem: the foundation of the FBP algorithm. FBP for parallel-beam, fan-beam, and cone-beam geometries will be discussed. To address the issue of radiation dose related to x-ray CT, recent advances in iterative reconstruction, their advantages, and clinical applications will also be described. Because of the nature of fundamental physics and mathematics, limitations in data acquisition, and non-ideal conditions of major system components, image artifact often arise

  15. TU-AB-207A-03: Image Quality, Dose, and Clinical Applications

    International Nuclear Information System (INIS)

    Dong, F.

    2016-01-01

    Practicing medical physicists are often time charged with the tasks of evaluating and troubleshooting complex image quality issues related to CT scanners. This course will equip them with a solid and practical understanding of common CT imaging chain and its major components with emphasis on acquisition physics and hardware, reconstruction, artifacts, image quality, dose, and advanced clinical applications. The core objective is to explain the effects of these major system components on the image quality. This course will not focus on the rapid-changing advanced technologies given the two-hour time limit, but the fundamental principles discussed in this course may facilitate better understanding of those more complicated technologies. The course will begin with an overview of CT acquisition physics and geometry. X-ray tube and CT detector are important acquisition hardware critical to the overall image quality. Each of these two subsystems consists of several major components. An in-depth description of the function and failure modes of these components will be provided. Examples of artifacts related to these failure modes will be presented: off-focal radiation, tube arcing, heel effect, oil bubble, offset drift effect, cross-talk effect, and bad pixels. The fundamentals of CT image reconstruction will first be discussed on an intuitive level. Approaches that do not require rigorous derivation of mathematical formulations will be presented. This is followed by a detailed derivation of the Fourier slice theorem: the foundation of the FBP algorithm. FBP for parallel-beam, fan-beam, and cone-beam geometries will be discussed. To address the issue of radiation dose related to x-ray CT, recent advances in iterative reconstruction, their advantages, and clinical applications will also be described. Because of the nature of fundamental physics and mathematics, limitations in data acquisition, and non-ideal conditions of major system components, image artifact often arise

  16. Search for methods and materials for practical use of residential radiation doses calculated via a standardized local methodology

    International Nuclear Information System (INIS)

    Cho, D.; Rhee, I.; Lee, G.-B.

    2003-01-01

    The aim of this work is on determination of standard parameters for computing residential doses per year near the nuclear power plants with consideration of local circumstances in Korea that may not be similar to those in the foreign developed power plants. All the data presented here was originated from four Korean nuclear power plants that are located along the seashore in the south provinces of Korea. We have selected critical nuclei, pathways and human organs related to the human exposure via simulated estimation with K-DOSE 60 based on the updated ICRP-60 with laborious addition of experimental input from key other Korean nuclear research organizations. From those results, we found that 1) the critical nuclides were found to be 3 H, 133 Xe, 60 Co for Kori plant and 14 C, 41 Ar for Wolsung plant. The most critical pathway was 'vegetable intake' for adults and 'milk intake' for infants. However, there was no preference in the effective organs, and 2) sensitivity analyses showed that the chemical composition in a nuclide much more influenced upon the radiation dose than any other input parameters such as food intake, radiation discharge, and transfer/concentration coefficients by more than 102 factor. The effect of transfer/concentration coefficients on the radiation dose was negligible. All input parameters showed highly estimated correlation with the radiation dose, approximated to 1.0, except for food intake in Wolsung power plant (partial correlation coefficient (PCC)=0.877). Consequently, we suggest that a prediction model or scenarios for food intake reflecting the current living trend and formal publications including details of chemical components in the critical nuclei from each plant are needed. Also, standardized domestic values of the parameters used in the calculation must replace the values of the existed or default-set imported factors via properly designed experiments and/or modelling such as transport of liquid discharge in waters nearby the

  17. Statin use and risks of influenza-related outcomes among older adults receiving standard-dose or high-dose influenza vaccines through Medicare during 2010-2015.

    Science.gov (United States)

    Izurieta, Hector S; Chillarige, Yoganand; Kelman, Jeffrey A; Forshee, Richard; Qiang, Yandong; Wernecke, Michael; Ferdinands, Jill M; Lu, Yun; Wei, Yuqin; Xu, Wenjie; Lu, Michael; Fry, Alicia; Pratt, Douglas; Shay, David K

    2018-02-09

    Statins are used to reduce cardiovascular disease risk. Recent studies suggest that statin use may be associated with an increased influenza risk among influenza vaccinees. We used Medicare data to evaluate associations between statins and risks of influenza-related encounters among vaccinees. In this retrospective cohort study, we identified Medicare beneficiaries aged >65 years who received high-dose (HD) or standard-dose (SD) influenza vaccines at pharmacies from 2010-11 through 2014-15. Statin users were matched to non-users by vaccine type, demographics, prior medical encounters, and comorbidities. We used multivariable Poisson models to estimate associations between statin use around the time of vaccination and risk of influenza-related encounters. Study outcomes included influenza-related office visits with a rapid test followed by dispensing of oseltamivir, and influenza-related hospitalizations (including emergency room visits), during high influenza circulation periods. The study included 1,403,651 statin users matched to non-users. Cohorts were well-balanced, with standardized mean differences ≤0.03 for all measured covariates. For statin users, compared to non-users, the adjusted relative risk was 1.086 (95% confidence interval [CI] 1.025-1.150) for influenza-related visits and 1.096 (95% CI 1.013-1.185) for influenza-related hospitalizations. The risk difference ranged from -0.02 to 0.23 for influenza-related visits and from -0.04 to 0.13 for hospitalizations, depending on season severity. Results were similar for HD and SD vaccinees, and for non-synthetic and synthetic statin users. Among 2.8 million Medicare beneficiaries, these results suggest that statin use around time of vaccination does not substantially affect the risk of influenza-related medical encounters among older adults. Published by Oxford University Press for the Infectious Diseases Society of America 2018. This work is written by (a) US Government employee(s) and is in the public

  18. Comparison of dose calculation algorithms for treatment planning in external photon beam therapy for clinical situations

    Science.gov (United States)

    Knöös, Tommy; Wieslander, Elinore; Cozzi, Luca; Brink, Carsten; Fogliata, Antonella; Albers, Dirk; Nyström, Håkan; Lassen, Søren

    2006-11-01

    A study of the performance of five commercial radiotherapy treatment planning systems (TPSs) for common treatment sites regarding their ability to model heterogeneities and scattered photons has been performed. The comparison was based on CT information for prostate, head and neck, breast and lung cancer cases. The TPSs were installed locally at different institutions and commissioned for clinical use based on local procedures. For the evaluation, beam qualities as identical as possible were used: low energy (6 MV) and high energy (15 or 18 MV) x-rays. All relevant anatomical structures were outlined and simple treatment plans were set up. Images, structures and plans were exported, anonymized and distributed to the participating institutions using the DICOM protocol. The plans were then re-calculated locally and exported back for evaluation. The TPSs cover dose calculation techniques from correction-based equivalent path length algorithms to model-based algorithms. These were divided into two groups based on how changes in electron transport are accounted for ((a) not considered and (b) considered). Increasing the complexity from the relatively homogeneous pelvic region to the very inhomogeneous lung region resulted in less accurate dose distributions. Improvements in the calculated dose have been shown when models consider volume scatter and changes in electron transport, especially when the extension of the irradiated volume was limited and when low densities were present in or adjacent to the fields. A Monte Carlo calculated algorithm input data set and a benchmark set for a virtual linear accelerator have been produced which have facilitated the analysis and interpretation of the results. The more sophisticated models in the type b group exhibit changes in both absorbed dose and its distribution which are congruent with the simulations performed by Monte Carlo-based virtual accelerator.

  19. Clinical review: Optimal dose of continuous renal replacement therapy in acute kidney injury.

    Science.gov (United States)

    Prowle, John R; Schneider, Antoine; Bellomo, Rinaldo

    2011-01-01

    Continuous renal replacement therapy (CRRT) is the preferred treatment for acute kidney injury in intensive care units (ICUs) throughout much of the world. Despite the widespread use of CRRT, controversy and center-specific practice variation in the clinical application of CRRT continue. In particular, whereas two single-center studies have suggested survival benefit from delivery of higher-intensity CRRT to patients with acute kidney injury in the ICU, other studies have been inconsistent in their results. Now, however, two large multi-center randomized controlled trials - the Veterans Affairs/National Institutes of Health Acute Renal Failure Trial Network (ATN) study and the Randomized Evaluation of Normal versus Augmented Level (RENAL) Replacement Therapy Study - have provided level 1 evidence that effluent flow rates above 25 mL/kg per hour do not improve outcomes in patients in the ICU. In this review, we discuss the concept of dose of CRRT, its relationship with clinical outcomes, and what target optimal dose of CRRT should be pursued in light of the high-quality evidence now available.

  20. Clinical outcome of high-dose-rate interstitial brachytherapy in patients with oral cavity cancer

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sung Uk; Cho, Kwan Ho; Moon, Sung Ho; Choi, Sung Weon; Park, Joo Yong; Yun, Tak; Lee, Sang Hyun; Lim, Young Kyung; Jeong, Chi Young [National Cancer Center, Goyang (Korea, Republic of)

    2014-12-15

    To evaluate the clinical outcome of high-dose-rate (HDR) interstitial brachytherapy (IBT) in patients with oral cavity cancer. Sixteen patients with oral cavity cancer treated with HDR remote-control afterloading brachytherapy using 192Ir between 2001 and 2013 were analyzed retrospectively. Brachytherapy was administered in 11 patients as the primary treatment and in five patients as salvage treatment for recurrence after the initial surgery. In 12 patients, external beam radiotherapy (50-55 Gy/25 fractions) was combined with IBT of 21 Gy/7 fractions. In addition, IBT was administered as the sole treatment in three patients with a total dose of 50 Gy/10 fractions and as postoperative adjuvant treatment in one patient with a total of 35 Gy/7 fractions. The 5-year overall survival of the entire group was 70%. The actuarial local control rate after 3 years was 84%. All five recurrent cases after initial surgery were successfully salvaged using IBT +/- external beam radiotherapy. Two patients developed local recurrence at 3 and 5 months, respectively, after IBT. The acute complications were acceptable (< or =grade 2). Three patients developed major late complications, such as radio-osteonecrosis, in which one patient was treated by conservative therapy and two required surgical intervention. HDR IBT for oral cavity cancer was effective and acceptable in diverse clinical settings, such as in the cases of primary or salvage treatment.

  1. Low-Dose (10-Gy) Total Skin Electron Beam Therapy for Cutaneous T-Cell Lymphoma: An Open Clinical Study and Pooled Data Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kamstrup, Maria R., E-mail: mkam0004@bbh.regionh.dk [Department of Dermatology, Bispebjerg Hospital, University of Copenhagen, Copenhagen (Denmark); Gniadecki, Robert [Department of Dermatology, Bispebjerg Hospital, University of Copenhagen, Copenhagen (Denmark); Iversen, Lars [Department of Dermatology, Aarhus University Hospital, Aarhus (Denmark); Skov, Lone [Department of Dermatology, Gentofte Hospital, University of Copenhagen, Copenhagen (Denmark); Petersen, Peter Meidahl [Department of Oncology and Hematology, Rigshospitalet, University of Copenhagen, Copenhagen (Denmark); Loft, Annika [Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, University of Copenhagen, Copenhagen (Denmark); Specht, Lena [Department of Oncology and Hematology, Rigshospitalet, University of Copenhagen, Copenhagen (Denmark)

    2015-05-01

    Purpose: Cutaneous T-cell lymphomas (CTCLs) are dominated by mycosis fungoides (MF) and Sézary syndrome (SS), and durable disease control is a therapeutic challenge. Standard total skin electron beam therapy (TSEBT) is an effective skin-directed therapy, but the possibility of retreatments is limited to 2 to 3 courses in a lifetime due to skin toxicity. This study aimed to determine the clinical effect of low-dose TSEBT in patients with MF and SS. Methods and Materials: In an open clinical study, 21 patients with MF/SS stages IB to IV were treated with low-dose TSEBT over <2.5 weeks, receiving a total dose of 10 Gy in 10 fractions. Data from 10 of these patients were published previously but were included in the current pooled data analysis. Outcome measures were response rate, duration of response, and toxicity. Results: The overall response rate was 95% with a complete cutaneous response or a very good partial response rate (<1% skin involvement with patches or plaques) documented in 57% of the patients. Median duration of overall cutaneous response was 174 days (5.8 months; range: 60-675 days). TSEBT-related acute adverse events (grade 1 or 2) were observed in 60% of patients. Conclusions: Low-dose (10-Gy) TSEBT offers a high overall response rate and is relatively safe. With this approach, reirradiation at times of relapse or progression is likely to be less toxic than standard dose TSEBT. It remains to be established whether adjuvant and combination treatments can prolong the beneficial effects of low-dose TSEBT.

  2. Clinical utility of coronary CT angiography with low-dose chest CT in the evaluation of patients with atypical chest pain: a preliminary report

    International Nuclear Information System (INIS)

    Lim, Soo Jin; Choo, Ki Seok; Kim, Chang Won

    2008-01-01

    To determine the clinical utility of coronary CT angiography (CCTA) with low-dose chest CT in the evaluation of patients with atypical chest pain. Ninety-six patients (mean age 60.2 years; age range, 41-68 years; 70 males) were referred for CCTA with low-dose chest CT (16-slice MDCT, Siemens) for an evaluation of atypical chest pain. When significant stenoses (lumen diameter reduction > 50%) were detected on CCTA, invasive coronary angiography (CA) was performed as the standard of reference. In all patients, medical chart review or telephone contact with patients was used to evaluate the contribution of CCTA with low-dose chest CT to the final clinical diagnosis, at least 6 months after performing CCTA. Among 96 patients, seven patients (7%) had significant stenoses as detected on CCTA, whereas two patients (2%) had significant stenoses and five patients had insignificant stenoses or no stenosis, as detected on conventional catheter angiography. In 18 (19%) of the 89 patients without significant stenosis detected on CCTA, this protocol provided additional information that suggested or confirmed an alternate clinical diagnosis. In patients with atypical chest pain, CCTA with low-dose chest CT could help to exclude ischemic heart disease and could provide important ancillary information for the final diagnosis

  3. Pharmacokinetics of single-dose sildenafil administered orally in clinically healthy dogs: Effect of feeding and dose proportionality.

    Science.gov (United States)

    Akabane, R; Sato, T; Sakatani, A; Miyagawa, Y; Tazaki, H; Takemura, N

    2018-01-19

    Basic information related to the pharmacokinetics of sildenafil in dogs is scarce. This study aimed to describe the pharmacokinetic properties of oral sildenafil and determine the effect of feeding and dose proportionality. The effect of feeding on pharmacokinetics of sildenafil (1 mg/kg) was investigated using a crossover study with six dogs. In addition, the dose proportionality of sildenafil ranging 1-4 mg/kg was evaluated using five dogs in the fasted states. The plasma concentrations of sildenafil were determined using high-performance liquid chromatography, and pharmacokinetic parameters were calculated using a noncompartmental analysis. Sildenafil administrations were well tolerated in all studies. Feeding reduced the area under the curve extrapolated to infinity (AUC inf ) and the maximum plasma concentration (C max ) significantly. The elimination half-life (T 1/2 ) did not differ between the fasted and the fed states. For dose proportionality, nonproportional increases in AUC inf and C max at 1-4 mg/kg doses were detected by a power model analysis. © 2018 John Wiley & Sons Ltd.

  4. Isoflurane Preconditioning at Clinically Relevant Doses Induce Protective Effects of Heme Oxygenase-1 on Hepatic Ischemia Reperfusion in Rats

    Directory of Open Access Journals (Sweden)

    Yu Weifeng

    2011-03-01

    Full Text Available Abstract Background Activation of heme oxygenase-1 (HO-1 has been proved to reduce damages to the liver in ischemia reperfusion injury. The objective of present study was to determine whether clinic relevant doses of isoflurane treatment could be sufficient to activate HO-1 inducing, which confers protective effect against hepatic ischemia-reperfusion injury. Methods The hepatic artery and portal vein to the left and the median liver lobes of forty male Sprague-Dawley rats were occluded for 60 minutes. Reperfusion was allowed for 4 hours before the animal subjects were sacrificed. Six groups (n = 12 were included in the study. A negative control group received sham operation and positive control group a standard ischemia-reperfusion regimen. The third group was pretreated with isoflurane prior to the ischemia-reperfusion. The fourth group received an HO-1 inhibitor zinc protoporphyrin (Znpp prior to the isoflurane pretreatment and the ischemia-reperfusion. The fifth group received Znpp alone before ischemia-reperfusion procedure, and the sixth group was administrated with a HO-1 inducer hemin prior to IR. HO-1 in the liver was measured using an enzymatic activity assay, a Western blot analysis, as well as immunohistochemical method. Extent of liver damage was estimated by determination of the serum transaminases, liver lipid peroxidation and hepatic histology. Infiltration of the liver by neutrophils was measured using a myeloperoxidase activity assay. TNFα mRNA in the liver was measured using RT-PCR. Results Isoflurane pretreatment significantly attenuated the hepatic injuries and inflammatory responses caused by the ischemia reperfusion. Selectively inhibiting HO-1 with ZnPP completed blocked the protective effects of isoflurane. Inducing HO-1 with hemin alone produced protective effects similar in magnitude to that of isoflurane. Conclusions Clinic relevant doses of isoflurane attenuate ischemia reperfusion injury in rats by increasing the

  5. Acute appendicitis: prospective evaluation of a diagnostic algorithm integrating ultrasound and low-dose CT to reduce the need of standard CT.

    Science.gov (United States)

    Poletti, Pierre-Alexandre; Platon, Alexandra; De Perrot, Thomas; Sarasin, Francois; Andereggen, Elisabeth; Rutschmann, Olivier; Dupuis-Lozeron, Elise; Perneger, Thomas; Gervaz, Pascal; Becker, Christoph D

    2011-12-01

    To evaluate an algorithm integrating ultrasound and low-dose unenhanced CT with oral contrast medium (LDCT) in the assessment of acute appendicitis, to reduce the need of conventional CT. Ultrasound was performed upon admission in 183 consecutive adult patients (111 women, 72 men, mean age 32) with suspicion of acute appendicitis and a BMI between 18.5 and 30 (step 1). No further examination was recommended when ultrasound was positive for appendicitis, negative with low clinical suspicion, or demonstrated an alternative diagnosis. All other patients underwent LDCT (30 mAs) (step 2). Standard intravenously enhanced CT (180 mAs) was performed after indeterminate LDCT (step 3). No further imaging was recommended after ultrasound in 84 (46%) patients; LDCT was obtained in 99 (54%). LDCT was positive or negative for appendicitis in 81 (82%) of these 99 patients, indeterminate in 18 (18%) who underwent standard CT. Eighty-six (47%) of the 183 patients had a surgically proven appendicitis. The sensitivity and specificity of the algorithm were 98.8% and 96.9%. The proposed algorithm achieved high sensitivity and specificity for detection of acute appendicitis, while reducing the need for standard CT and thus limiting exposition to radiation and to intravenous contrast media.

  6. Acute appendicitis: prospective evaluation of a diagnostic algorithm integrating ultrasound and low-dose CT to reduce the need of standard CT

    Energy Technology Data Exchange (ETDEWEB)

    Poletti, Pierre-Alexandre; Platon, Alexandra [University Hospital of Geneva, Department of Radiology, Geneva (Switzerland); University Hospital of Geneva, Emergency Center, Geneva (Switzerland); Perrot, Thomas de; Becker, Christoph D. [University Hospital of Geneva, Department of Radiology, Geneva (Switzerland); Sarasin, Francois; Rutschmann, Olivier [University Hospital of Geneva, Emergency Center, Geneva (Switzerland); Andereggen, Elisabeth [University Hospital of Geneva, Emergency Center, Geneva (Switzerland); University Hospital of Geneva, Department of Surgery, Geneva (Switzerland); Dupuis-Lozeron, Elise; Perneger, Thomas [University Hospital of Geneva, Division of Clinical Epidemiology, Geneva (Switzerland); Gervaz, Pascal [University Hospital of Geneva, Department of Surgery, Geneva (Switzerland)

    2011-12-15

    To evaluate an algorithm integrating ultrasound and low-dose unenhanced CT with oral contrast medium (LDCT) in the assessment of acute appendicitis, to reduce the need of conventional CT. Ultrasound was performed upon admission in 183 consecutive adult patients (111 women, 72 men, mean age 32) with suspicion of acute appendicitis and a BMI between 18.5 and 30 (step 1). No further examination was recommended when ultrasound was positive for appendicitis, negative with low clinical suspicion, or demonstrated an alternative diagnosis. All other patients underwent LDCT (30 mAs) (step 2). Standard intravenously enhanced CT (180 mAs) was performed after indeterminate LDCT (step 3). No further imaging was recommended after ultrasound in 84 (46%) patients; LDCT was obtained in 99 (54%). LDCT was positive or negative for appendicitis in 81 (82%) of these 99 patients, indeterminate in 18 (18%) who underwent standard CT. Eighty-six (47%) of the 183 patients had a surgically proven appendicitis. The sensitivity and specificity of the algorithm were 98.8% and 96.9%. The proposed algorithm achieved high sensitivity and specificity for detection of acute appendicitis, while reducing the need for standard CT and thus limiting exposition to radiation and to intravenous contrast media. (orig.)

  7. Sunscreen compliance with regional clinical practice guidelines and product labeling standards in New Zealand.

    Science.gov (United States)

    Sporer, Matthias E; Mathy, Joanna E; Kenealy, John; Mathy, Jon A

    2016-03-01

    INTRODUCTION For general practitioners, practice nurses and community pharmacists in New Zealand, a core duty is to educate patients about sun protection. We aimed to evaluate compliance of locally available sunscreens with regional clinical practice guidelines and sunscreen labelling standards, to assist clinicians in advising consumers on sunscreen selection. METHODS We audited all sunscreens available at two Auckland stores for three New Zealand sunscreen retailers. We then assessed compliance with accepted regional clinical practice guidelines for sun protection from the New Zealand Guidelines Group. We further assessed compliance with regional Australia/New Zealand consumer standards for sunscreen labelling. RESULTS All sunscreens satisfied clinical guidelines for broad-spectrum protection, and 99% of sunscreens met or exceeded clinical guidelines for minimal Sun Protection Factor. Compliance with regional standardized labelling guidelines is voluntary in New Zealand and 27% of audited sunscreens were not fully compliant with SPF labelling standards. DISCUSSION Sunscreens were generally compliant with clinical guidelines for minimal sun protection. However there was substantial noncompliance with regional recommendations for standardized sunscreen labelling. Primary health care clinicians should be aware that this labelling noncompliance may mislead patients into thinking some sunscreens offer more sun protection than they do. Mandatory compliance with the latest regional labelling standards would simplify sunscreen selection by New Zealand consumers. KEYWORDS Sunscreen; Sun Protection Factor; SPF; Skin Neoplasms; Melanoma; Skin Cancer Prevention.

  8. A comparative analysis of quality management standards for contract research organisations in clinical trials.

    Science.gov (United States)

    Murray, Elizabeth; McAdam, Rodney

    2007-01-01

    This article compares and contrasts the main quality standards in the highly regulated pharmaceutical industry with specific focus on Good Clinical Practice (GCP), the standard for designing, conducting, recording and reporting clinical trials involving human participants. Comparison is made to ISO quality standards, which can be applied to all industries and types of organisation. The study is then narrowed to that of contract research organisations (CROs) involved in the conduct of clinical trials. The paper concludes that the ISO 9000 series of quality standards can act as a company-wide framework for quality management within such organisations by helping to direct quality efforts on a long-term basis without any loss of compliance. This study is valuable because comparative analysis in this domain is uncommon.

  9. Standard requirements for GCP-compliant data management in multinational clinical trials

    DEFF Research Database (Denmark)

    Ohmann, Christian; Kuchinke, Wolfgang; Canham, Steve

    2011-01-01

    A recent survey has shown that data management in clinical trials performed by academic trial units still faces many difficulties (e.g. heterogeneity of software products, deficits in quality management, limited human and financial resources and the complexity of running a local computer centre......). Unfortunately, no specific, practical and open standard for both GCP-compliant data management and the underlying IT-infrastructure is available to improve the situation. For that reason the "Working Group on Data Centres" of the European Clinical Research Infrastructures Network (ECRIN) has developed...... a standard specifying the requirements for high quality GCP-compliant data management in multinational clinical trials....

  10. Clinical responses after total body irradiation by over permissible dose of γ-rays in one time

    International Nuclear Information System (INIS)

    Jiang Benrong; Wang Guilin; Liu Huilan; Tang Xingsheng; Ai Huisheng

    1990-01-01

    The clinical responses of patients after total body over permissilbe dose γ-ray irradiation were observed and analysed. The results showed: when the dose was above 5 cGy, there was some immunological depression, but no significant change in hematopoietic functions. 5 cases showed some transient changes of ECG, perhaps due to vagotonia caused by psychological imbalance, One case vomitted 3-4 times after 28 cGy irradiation, this suggested that a few times of vomitting had no significance in the estimation of the irradiated dose and the whole clinical manifestations must be concretely analysed

  11. Feasibility study of astronaut standardized career dose limits in LEO and the outlook for BLEO

    Science.gov (United States)

    McKenna-Lawlor, Susan; Bhardwaj, A.; Ferrari, Franco; Kuznetsov, Nikolay; Lal, A. K.; Li, Yinghui; Nagamatsu, Aiko; Nymmik, Rikho; Panasyuk, Michael; Petrov, Vladislav; Reitz, Guenther; Pinsky, Lawrence; Muszaphar Shukor, Sheikh; Singhvi, A. K.; Straube, Ulrich; Tomi, Leena; Townsend, Lawrence

    2014-11-01

    Cosmic Study Group SG 3.19/1.10 was established in February 2013 under the aegis of the International Academy of Astronautics to consider and compare the dose limits adopted by various space agencies for astronauts in Low Earth Orbit. A preliminary definition of the limits that might later be adopted by crews exploring Beyond Low Earth Orbit was, in addition, to be made. The present paper presents preliminary results of the study reported at a Symposium held in Turin by the Academy in July 2013. First, an account is provided of exposure limits assigned by various partner space agencies to those of their astronauts that work aboard the International Space Station. Then, gaps in the scientific and technical information required to safely implement human missions beyond the shielding provided by the geomagnetic field (to the Moon, Mars and beyond) are identified. Among many recommendations for actions to mitigate the health risks potentially posed to personnel Beyond Low Earth Orbit is the development of a preliminary concept for a Human Space Awareness System to: provide for crewed missions the means of prompt onboard detection of the ambient arrival of hazardous particles; develop a strategy for the implementation of onboard responses to hazardous radiation levels; support modeling/model validation that would enable reliable predictions to be made of the arrival of hazardous radiation at a distant spacecraft; provide for the timely transmission of particle alerts to a distant crewed vehicle at an emergency frequency using suitably located support spacecraft. Implementation of the various recommendations of the study can be realized based on a two pronged strategy whereby Space Agencies/Space Companies/Private Entrepreneurial Organizations etc. address the mastering of required key technologies (e.g. fast transportation; customized spacecraft design) while the International Academy of Astronautics, in a role of handling global international co-operation, organizes

  12. Determination of Tedizolid susceptibility interpretive criteria for gram-positive pathogens according to clinical and laboratory standards institute guidelines.

    Science.gov (United States)

    Bensaci, Mekki; Flanagan, Shawn; Sandison, Taylor

    2018-03-01

    For effective antibacterial therapy, physicians require qualitative test results using susceptibility breakpoints provided by clinical microbiology laboratories. This article summarizes the key components used to establish the Clinical Laboratory Standards Institute (CLSI) breakpoints for tedizolid. First, in vitro studies using recent surveillance and clinical trial isolates ascertained minimal inhibitory concentration (MIC) distributions against pertinent organisms, including staphylococci, streptococci, and enterococci. Studies in animal models of infection determined rates of antibacterial efficacy and survival following administration of tedizolid phosphate at doses equivalent to those in humans. Pharmacokinetic and pharmacodynamic analyses examined the relationship between plasma concentrations and MICs against the target organism. Finally, clinical trials assessed clinical and microbiologic outcomes by MIC. All these data were evaluated and combined to obtain the ratified CLSI susceptibility criteria for tedizolid of ≤0.5μg/mL for Staphylococcus aureus, Streptococcus pyogenes, Streptococcus agalactiae, and Enterococcus faecalis and ≤0.25μg/mL for Streptococcus anginosus group. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. MO-D-213-08: Remote Dosimetric Credentialing for Clinical Trials with the Virtual EPID Standard Phantom Audit (VESPA)

    Energy Technology Data Exchange (ETDEWEB)

    Lehmann, J [Calvary Mater Newcastle, Newcastle, NSW (Australia); University of Sydney, Sydney, NSW (Australia); Miri, N [University of Newcastle, Newcastle, NSW (Australia); Vial, P [Liverpool Hospital, Liverpool, NSW (Australia); Hatton, J [Trans Tasman Radiation Oncology Group (TROG), Newcastle, NSW (Australia); Zwan, B; Sloan, K [Gosford Hospital, Gosford, NSW (Australia); Craig, A; Beenstock, V [Canterbury Regional Cancer and Haematology Service, Christchurch (New Zealand); Molloy, T [Orange Hospital, Orange, NSW (Australia); Greer, P [Calvary Mater Newcastle, Newcastle, NSW (Australia); University of Newcastle, Newcastle, NSW (Australia)

    2015-06-15

    Purpose: Report on implementation of a Virtual EPID Standard Phantom Audit (VESPA) for IMRT to support credentialing of facilities for clinical trials. Data is acquired by local facility staff and transferred electronically. Analysis is performed centrally. Methods: VESPA is based on published methods and a clinically established IMRT QA procedure, here extended to multi-vendor equipment. Facilities, provided with web-based comprehensive instructions and CT datasets, create IMRT treatment plans. They deliver the treatments directly to their EPID without phantom or couch in the beam. They also deliver a set of simple calibration fields. Collected EPID images are uploaded electronically. In the analysis, the dose is projected back into a virtual phantom and 3D gamma analysis is performed. 2D dose planes and linear dose profiles can be analysed when needed for clarification. Results: Pilot facilities covering a range of planning and delivery systems have performed data acquisition and upload successfully. Analysis showed agreement comparable to local experience with the method. Advantages of VESPA are (1) fast turnaround mainly driven by the facility’s capability to provide the requested EPID images, (2) the possibility for facilities performing the audit in parallel, as there is no need to wait for a phantom, (3) simple and efficient credentialing for international facilities, (4) a large set of data points, and (5) a reduced impact on resources and environment as there is no need to transport heavy phantoms or audit staff. Limitations of the current implementation of VESPA for trials credentialing are that it does not provide absolute dosimetry, therefore a Level 1 audit still required, and that it relies on correctly delivered open calibration fields, which are used for system calibration. Conclusion: The implemented EPID based IMRT audit system promises to dramatically improve credentialing efficiency for clinical trials and wider applications. VESPA for VMAT

  14. Radiation dose responses for chemoradiation therapy of pancreatic cancer: an analysis of compiled clinical data using biophysical models.

    Science.gov (United States)

    Moraru, Ion C; Tai, An; Erickson, Beth; Li, X Allen

    2014-01-01

    We analyzed recent clinical data obtained from chemoradiation of unresectable, locally advanced pancreatic cancer (LAPC) in order to examine possible benefits from radiation therapy dose escalation. A modified linear quadratic model was used to fit clinical tumor response and survival data of chemoradiation treatments for LAPC reported from 20 institutions. Biophysical radiosensitivity parameters were extracted from the fits. Examination of the clinical data demonstrated an enhancement in tumor response with higher irradiation dose, an important clinical result for palliation and quality of life. Little indication of improvement in 1-year survival with increased radiation dose was observed. Possible dose escalation schemes are proposed based on calculations of the biologically effective dose required for a 50% tumor response rate. Based on the evaluation of tumor response data, the escalation of radiation dose presents potential clinical benefits which when combined with normal tissue complication analyses may result in improved treatment outcome for locally advanced pancreatic cancer patients. Copyright © 2014 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.

  15. Evaluation of a Net Dose-Reducing Organ-Based Tube Current Modulation Technique: Comparison With Standard Dose and Bismuth-Shielded Acquisitions.

    Science.gov (United States)

    Lambert, Jack W; Gould, Robert G

    2016-06-01

    The purpose of this study was to compare the dose and image noise associated with two methods of radiation dose reduction to the superficial anterior organs: bismuth shielding and a net dose-reducing organ-based tube current modulation TCM technique. Three scanning modes-the reference dose, bismuth-shielded, and organ dose-modulated modes-were evaluated. With the use of an anthropomorphic phantom, surface doses to the eye, thyroid, and female breast were measured using optically stimulated luminescence detectors. A CT dose index (CTDI) phantom was used to compare doses with the overall phantom volume in the different modes. The dose to the anterior surface was reduced by 35%, 42%, and 37% in the head, neck, and chest regions, respectively, when the bismuth-shielded scanning mode was used, whereas surface dose reductions of 20%, 34%, and 38%, respectively, were noted for the organ-based TCM scanning mode. The CTDI-type dose was reduced by 13%, 14%, and 17% in the head, neck, and chest regions, respectively, when the bismuth-shielded mode was used, whereas dose reductions of 9%, 18%, and 20%, respectively, were observed for the organ-based TCM mode. Anterior image noise increased by 0.1, 9.5, and 0.7 HU in the head, neck, and chest regions, respectively, when the bismuth-shielded mode was used. These findings compared with increases in image noise of 0.1, 0.5, and 0.6 HU, respectively, for the organ-based TCM mode. The implementation of organ-based TCM reduces the net tube current per rotation, so no body region receives increased radiation exposure. The use of this method allows the dose to the anterior surface to be reduced to an extent similar to that observed with the use of the bismuth shield, yet it does not produce the image quality degradation associated with bismuth shielding.

  16. Cannabidiol is a partial agonist at dopamine D2High receptors, predicting its antipsychotic clinical dose.

    Science.gov (United States)

    Seeman, P

    2016-10-18

    Although all current antipsychotics act by interfering with the action of dopamine at dopamine D2 receptors, two recent reports showed that 800 to 1000 mg of cannabidiol per day alleviated the signs and symptoms of schizophrenia, although cannabidiol is not known to act on dopamine receptors. Because these recent clinical findings may indicate an important exception to the general rule that all antipsychotics interfere with dopamine at dopamine D2 receptors, the present study examined whether cannabidiol acted directly on D2 receptors, using tritiated domperidone to label rat brain striatal D2 receptors. It was found that cannabidiol inhibited the binding of radio-domperidone with dissociation constants of 11 nm at dopamine D2High receptors and 2800 nm at dopamine D2Low receptors, in the same biphasic manner as a dopamine partial agonist antipsychotic drug such as aripiprazole. The clinical doses of cannabidiol are sufficient to occupy the functional D2High sites. it is concluded that the dopamine partial agonist action of cannabidiol may account for its clinical antipsychotic effects.

  17. Selective Internal Radiation Therapy With Yttrium-90 Glass Microspheres: Biases and Uncertainties in Absorbed Dose Calculations Between Clinical Dosimetry Models.

    Science.gov (United States)

    Mikell, Justin K; Mahvash, Armeen; Siman, Wendy; Baladandayuthapani, Veera; Mourtada, Firas; Kappadath, S Cheenu

    2016-11-15

    To quantify differences that exist between dosimetry models used for 90 Y selective internal radiation therapy (SIRT). Retrospectively, 37 tumors were delineated on 19 post-therapy quantitative 90 Y single photon emission computed tomography/computed tomography scans. Using matched volumes of interest (VOIs), absorbed doses were reported using 3 dosimetry models: glass microsphere package insert standard model (SM), partition model (PM), and Monte Carlo (MC). Univariate linear regressions were performed to predict mean MC from SM and PM. Analysis was performed for 2 subsets: cases with a single tumor delineated (best case for PM), and cases with multiple tumors delineated (typical clinical scenario). Variability in PM from the ad hoc placement of a single spherical VOI to estimate the entire normal liver activity concentration for tumor (T) to nontumoral liver (NL) ratios (TNR) was investigated. We interpreted the slope of the resulting regression as bias and the 95% prediction interval (95%PI) as uncertainty. MC NL single represents MC absorbed doses to the NL for the single tumor patient subset; other combinations of calculations follow a similar naming convention. SM was unable to predict MC T single or MC T multiple (p>.12, 95%PI >±177 Gy). However, SM single was able to predict (p<.012) MC NL single , albeit with large uncertainties; SM single and SM multiple yielded biases of 0.62 and 0.71, and 95%PI of ±40 and ± 32 Gy, respectively. PM T single and PM T multiple predicted (p<2E-6) MC T single and MC T multiple with biases of 0.52 and 0.54, and 95%PI of ±38 and ± 111 Gy, respectively. The TNR variability in PM T single increased the 95%PI for predicting MC T single (bias = 0.46 and 95%PI = ±103 Gy). The TNR variability in PM T multiple modified the bias when predicting MC T multiple (bias = 0.32 and 95%PI = ±110 Gy). The SM is unable to predict mean MC tumor absorbed dose. The PM is statistically correlated with mean MC, but the

  18. Standardized exchange of clinical documents--towards a shared care paradigm in glaucoma treatment.

    Science.gov (United States)

    Gerdsen, F; Müller, S; Jablonski, S; Prokosch, H-U

    2006-01-01

    The exchange of medical data from research and clinical routine across institutional borders is essential to establish an integrated healthcare platform. In this project we want to realize the standardized exchange of medical data between different healthcare institutions to implement an integrated and interoperable information system supporting clinical treatment and research of glaucoma. The central point of our concept is a standardized communication model based on the Clinical Document Architecture (CDA). Further, a communication concept between different health care institutions applying the developed document model has been defined. With our project we have been able to prove that standardized communication between an Electronic Medical Record (EMR), an Electronic Health Record (EHR) and the Erlanger Glaucoma Register (EGR) based on the established conceptual models, which rely on CDA rel.1 level 1 and SCIPHOX, could be implemented. The HL7-tool-based deduction of a suitable CDA rel.2 compliant schema showed significant differences when compared with the manually created schema. Finally fundamental requirements, which have to be implemented for an integrated health care platform, have been identified. An interoperable information system can enhance both clinical treatment and research projects. By automatically transferring screening findings from a glaucoma research project to the electronic medical record of our ophthalmology clinic, clinicians could benefit from the availability of a longitudinal patient record. The CDA as a standard for exchanging clinical documents has demonstrated its potential to enhance interoperability within a future shared care paradigm.

  19. Verification the 25-kgy dose using the iso standard iso/tr 13409 for the production of bone grafts

    International Nuclear Information System (INIS)

    Otero, I.; Barrera, L.; Diaz, A.; Napoles, D.; Sanchez, E

    2001-01-01

    The purpose of this work was to verify the 25 Gy dose using the ISO standard ISO/TR 13409 for the production of bone grafts from the Tissue Bank ORTOP of the Complejo Cientifico Ortopedico Internacional Frank Pais. We performed two principal microbiological activities: bioburden estimate, pre-sterilization count plus a compensation for the efficiency of the recovery method, by ISO 11737-1 and test of sterility by ISO 11737-2. The techniques for Bioburden estimation could be direct or indirect. Choice of direct vs. indirect depends on number of contaminating micro-organisms, product configuration, ability to remove microbial contamination, effect of removal method on microbial viability, types and location of micro-organisms, nature of product and culture conditions. For a test of sterility, he product unit or SIP putted direct immersion in educated culture medium and incubate. Keep precaution to minimize level to the false positives is necessary

  20. Clinical effects of chronic low doses irradiation (11 years after Chernobyl accident)

    International Nuclear Information System (INIS)

    Romanenko, A.Y.; Bebeshko, V.G.

    1997-01-01

    Estimation of clinical effects of influence low doses of irradiation as the result of the Chernobyl accident on the human organism is presented in this report. The results of the investigations are concerning to changings in different organs and systems of inhabitants of the contamination territories and among clean-up workers. Increasing of morbidity of digestive and nervous systems is notified. Increase of thyroid cancer, chronic thyroidities and hypothyreouses is resisted in clean-up workers in dynamic observation. Highly morbidity of bronchopulmonal system and blood circulation system is revealed. High level of compensative and adaptive reactions of immune and hemopoietic systems is notified. Excesses of leukemias and lymphomas in inhabitants of the contamination territories is not demonstrated but tendency for increasing quantity cases of oncohematological diseases (leukemias, lymphomas, MDS) among clean-up workers IV-VII 1986 are absent. A dynamic of health state of children injured as a result of Chernobyl accident is characterized with continues negative tendencies. (author)

  1. Survey of image quality and patient dose in simple radiographic examinations: establishing guidance levels and comparison with international standards

    International Nuclear Information System (INIS)

    Manatrakul, N.; Bunsoong, T.; Krisanachinda, A.; Suwanpradit, P.; Rungruengthanakit, P.; Kanchart, S.; Chaiwong, Rajikorn; Tsapakig, V.A.

    2008-01-01

    Purpose: To investigate image quality and patient dose for commonly radiographic examinations in Thailand, to establish national reference or guidance levels (GL) and compare with international standards, as part of an International Atomic Energy Agency (IAEA) project on Radiation Protection of Patients and Medical Exposure Control (RAS/9/034 and RAS/9/047). Materials and Methods: Film reject rate analysis, image quality and patient dose assessment before and after Quality Control (QC) implementation were investigated in 8 X-ray machines in 4 hospitals. Air kerma (in mGy) at 1 meter focus-detector-distance for different kVp settings for each X-ray machines were measured using an ionization chamber under standardized condition. The entrance skin air kerma (ESAK) for Chest PA, Lumbar spine AP, Lumbar spine LAT, Pelvis AP, Abdomen AP, Skull AP and Skull LAT were calculated for at least 10 adult patients of average body mass (60 to 80 kg) for each projection. The obtained values were compared with international standards. Results: The highest film rejection rate reduction recorded after corrective actions from 9.15% to 6.8%. Mean ESAK values were less than international standards both before and after QC implementation in all projections but Chest PA projection. Maximum ESAK in Chest PA projection before corrective action was 0.55 mGy which was higher than the IAEA GL of 0.2 mGy. However, it was reduced to 0.25 mGy after QC tests on X- ray machine and using high kilovoltage (kV) technique. Conclusion: Proposed national GL of Thailand were obtained by estimating the 3rd quartile of the whole sample: Chest PA: 0.1 mGy, Lumbar Spine AP: 2.1 mGy, Lumbar Spine LAT: 6.3 mGy, Pelvis AP: 1.8 mGy, Abdomen: 1.5 mGy, Skull PA: 1.3 mGy and Skull LAT: 0.9 mGy. (author)

  2. Acute effects of exposure to vapours of standard and dearomatized white spirits in humans. 1. Dose-finding study.

    Science.gov (United States)

    Ernstgård, Lena; Lind, Birger; Johanson, Gunnar

    2009-04-01

    A move from 'standard' white spirit (stdWS, 15-20% aromatics) to low-aromatic or dearomatized white spirit (deWS) has been seen, as the latter are considered to carry a smaller risk of health effects. However, data on health risks of deWS on humans are sparse. The aim of this dose-finding study was to identify thresholds of irritation and central nervous system (CNS) effects of the two types of white spirit, as a basis for more detailed studies. Four female and four male healthy volunteers rated symptoms related to irritation, smell and CNS effects on a 0-100 mm visual analogue scale while exposed to increasing levels of deWS or stdWS in eight 10 min steps from 0.5 to 600 mg m(-3). Combined ratings of questions related to irritation revealed statistically significant increases compared with pre-exposure ratings at 50 mg m(-3) and higher exposures. The ratings increased in a dose-dependent fashion, the medians reaching 'somewhat' for stdWS and 'hardly at all' for deWS. Higher ratings of irritation were found during exposure to stdWS compared with deWS, reaching significance only at 500 mg m(-3). The combined ratings of CNS effects reached 'hardly at all', and were significantly increased only for stdWS at 500 and 600 mg m(-3).

  3. Increased apoptotic potential and dose-enhancing effect of gold nanoparticles in combination with single-dose clinical electron beams on tumor-bearing mice

    International Nuclear Information System (INIS)

    Chang Mengya; Chen Yuhung; Chang Chihjui; Chen Helen H-W; Wu Chaoliang; Shiau Aili

    2008-01-01

    High atomic number material, such as gold, may be used in conjunction with radiation to provide dose enhancement in tumors. In the current study, we investigated the dose-enhancing effect and apoptotic potential of gold nanoparticles in combination with single-dose clinical electron beams on B16F10 melanoma tumor-bearing mice. We revealed that the accumulation of gold nanoparticles was detected inside B16F10 culture cells after 18 h of incubation, and moreover, the gold nanoparticles were shown to be colocalized with endoplasmic reticulum and Golgi apparatus in cells. Furthermore, gold nanoparticles radiosensitized melanoma cells in the colony formation assay (P=0.02). Using a B16F10 tumor-bearing mouse model, we further demonstrated that gold nanoparticles in conjunction with ionizing radiation significantly retarded tumor growth and prolonged survival compared to the radiation alone controls (P<0.05). Importantly, an increase of apoptotic signals was detected inside tumors in the combined treatment group (P<0.05). Knowing that radiation-induced apoptosis has been considered a determinant of tumor responses to radiation therapy, and the length of tumor regrowth delay correlated with the extent of apoptosis after single-dose radiotherapy, these results may suggest the clinical potential of gold nanoparticles in improving the outcome of melanoma radiotherapy. (author)

  4. Clinical results of definitive-dose (50 Gy/25 fractions) preoperative chemoradiotherapy for unresectable esophageal cancer

    International Nuclear Information System (INIS)

    Ishikawa, Kazuki; Nakamatsu, Kiyoshi; Shiraishi, Osamu; Yasuda, Takushi; Nishimura, Yasumasa

    2015-01-01

    The clinical results of definitive-dose preoperative chemoradiotherapy (CRT) of 50 Gy/25 fractions/5 weeks for unresectable esophageal cancer were analyzed. Inclusion criteria were unresectable esophageal squamous cell carcinoma with T4b or mediastinal lymph nodes invading to the trachea or aorta. Radiation therapy of 50 Gy/25 fractions/5 weeks was combined concurrently with two courses of FP therapy (CDDP 70 mg/m 2 + 5-FU 700 mg/m 2 /d x 5 days: day 1-5, day 29-33). Tumor response was evaluated 4 weeks after completion of RT. Subtotal esophagectomy was planned 6-8 weeks after RT. Thirty patients (26 male and 4 female) aged from 50-78 years (median 66) were enrolled between 2008 and 2011. The clinical stages according to the 7th edition of UICC were stages II/III/IV, 1/23/6; T1/2/3/4, 1/1/4/24; and N0/1/2/3, 3/25/1/1. All 30 patients completed RT of 50 Gy/ 25 fractions. Initial tumor responses were 21 patients with resectable disease, 7 with unresectable disease, and 2 with progressive disease. Subtotal esophagectomy was performed in 18 (60%) of the 30 patients. Pathological complete response was obtained in five (28%) patients. There were two patients with hospitalization death after surgery (11%). Six of the 7 patients who still had unresectable disease were treated with 1-3 courses of docetaxel, CDDP and 5-FU. Three patients treated without surgery showed long-term survival. The 3-year locoregional control rate and the 3-year overall survival rate for the 30 patients were 70 and 49%, respectively. Definitive-dose preoperative CRT was feasible, and is a promising treatment strategy for unresectable esophageal cancer. (author)

  5. A clinical evaluation of statin pleiotropy: statins selectively and dose-dependently reduce vascular inflammation.

    Directory of Open Access Journals (Sweden)

    Evelien van der Meij

    Full Text Available Statins are thought to reduce vascular inflammation through lipid independent mechanisms. Evaluation of such an effect in atherosclerotic disease is complicated by simultaneous effects on lipid metabolism. Abdominal aortic aneurysms (AAA are part of the atherosclerotic spectrum of diseases. Unlike atherosclerotic occlusive disease, AAA is not lipid driven, thus allowing direct evaluation of putative anti-inflammatory effects. The anti-inflammatory potency of increasing doses (0, 20 or 40 mg/day simvastatin or atorvastatin was evaluated in 63 patients that were at least 6 weeks on statin therapy and who underwent open AAA repair. A comprehensive analysis using immunohistochemistry, mRNA and protein analyses was applied on aortic wall samples collected during surgery. The effect of statins on AAA growth was analyzed in a separate prospective study in incorporating 142 patients. Both statins equally effectively and dose-dependently reduced aortic wall expression of NFκB regulated mediators (i.e. IL-6 (P<0.001 and MCP-1 (P<0.001; shifted macrophage polarization towards a M2 phenotype (P<0.0003; selectively reduced macrophage-related markers such as cathepsin K and S (P<0.009 and 0.0027 respectively, and ALOX5 (P<0.0009, and reduced vascular wall NFκB activity (40 mg/day group, P<0.016. No effect was found on other cell types. Evaluation of the clinical efficacy of statins to reduce AAA progression did not indicate an effect of statins on aneurysm growth (P<0.337. Hence, in the context of AAA the clinical relevance of statins pleiotropy appears minimal.

  6. Re-establishment of the air kerma and ambient dose equivalent standards for the BIPM protection-level 60Co beam

    International Nuclear Information System (INIS)

    Kessler, C.; Roger, P.

    2005-07-01

    The air kerma and ambient dose equivalent standards for the protection-level 60 Co beam have been re-established following the repositioning of the irradiator and modifications to the beam. Details concerning the standards and the new uncertainty budgets are described in this report with their implications for dosimetry comparisons and calibrations. (authors)

  7. Minimum reporting standards for clinical research on groin pain in athletes

    DEFF Research Database (Denmark)

    Delahunt, Eamonn; Thorborg, Kristian; Khan, Karim M

    2015-01-01

    are provided in relation to: (1) study methodology, (2) study participants and injury history, (3) clinical examination, (4) clinical assessment and (5) radiology. Adherence to these minimum reporting standards will strengthen the quality and transparency of research conducted on groin pain in athletes......Groin pain in athletes is a priority area for sports physiotherapy and sports medicine research. Heterogeneous studies with low methodological quality dominate research related to groin pain in athletes. Low-quality studies undermine the external validity of research findings and limit the ability...... to generalise findings to the target patient population. Minimum reporting standards for research on groin pain in athletes are overdue. We propose a set of minimum reporting standards based on best available evidence to be utilised in future research on groin pain in athletes. Minimum reporting standards...

  8. Postoperative vaginal cuff irradiation using high dose rate remote afterloading: a Phase II clinical protocol

    International Nuclear Information System (INIS)

    Noyes, William R.; Bastin, Kenneth; Edwards, Scott A.; Buchler, Dolores A.; Stitt, Judith A.; Thomadsen, Bruce R.; Fowler, Jack F.; Kinsella, Timothy J.

    1995-01-01

    Purpose: In September 1989, a postoperative Phase II high dose rate (HDR) brachytherapy protocol was started for International Federation of Gynecology and Obstetrics (FIGO) Stage I endometrial adenocarcinoma. This review reports the overall survival, local control, and complication rates for the initial 63 patients treated in this Phase II study. Methods and Materials: High dose rate brachytherapy was delivered using an Iridium-192 HDR remote afterloader. Sixty-three patients were entered into the Phase II protocol, each receiving two vaginal cuff treatments 1 week apart (range 4-12 days) with vaginal ovoids (diameter 2.0-3.0 cm). No patient received adjuvant external beam radiation. A dose of 32.4 Gy in two fractions was prescribed to the ovoid surface in 63 patients. The first three patients treated at our institution received 15, 16.2, and 29 Gy, respectively, to determine acute effects. Results: At a median follow-up of 1.6 years (range 0.75-4.3 years) no patient has developed a vaginal cuff recurrence. One regional recurrence (1.6%) occurred at 1.2 years at the pelvic side wall. This patient is alive and without evidence of disease 7 months after completion of salvage irradiation, which resulted in the only vaginal stenosis (1.6%). Fourteen patients (22%) experienced vaginal apex fibrosis by physical exam, which was clinically symptomatic in four patients. Two patients reported stress incontinence; however, these symptoms were noted prior to their HDR therapy. One patient died 2.4 years after HDR therapy due to cardiovascular disease without evidence of cancer at autopsy. Conclusion: Preliminary results of our phase II HDR vaginal cuff protocol for postoperative FIGO Stage IA, Grade 3 or Stage IB, Grade 1-2 patients demonstrate that 32.4 Gy in two fractions is well tolerated by the vaginal cuff mucosa. Local control appears comparable to our prior experience and others with low dose rate (LDR) brachytherapy. Additional patient accrual and further follow

  9. High dose rate versus low dose rate brachytherapy for oral cancer--a meta-analysis of clinical trials.

    Science.gov (United States)

    Liu, Zhenxing; Huang, Shengyun; Zhang, Dongsheng

    2013-01-01

    To compare the efficacy and safety of high dose rate (HDR) and low dose rate (LDR) brachytherapy in treating early-stage oral cancer. A systematic search of MEDLINE, EMBASE and Cochrane Library databases, restricted to English language up to June 1, 2012, was performed to identify potentially relevant studies. Only randomized controlled trials (RCT) and controlled trials that compared HDR to LDR brachytherapy in treatment of early-stage oral cancer (stages I, II and III) were of interest. Two investigators independently extracted data from retrieved studies and controversies were solved by discussion. Meta-analysis was performed using RevMan 5.1. One RCT and five controlled trials (607 patients: 447 for LDR and 160 for HDR) met the inclusion criteria. The odds ratio showed no statistically significant difference between LDR group and HDR group in terms of local recurrence (OR = 1.12, CI 95% 0.62-2.01), overall mortality (OR = 1.01, CI 95% 0.61-1.66) and Grade 3/4 complications (OR = 0.86, CI 95% 0.52-1.42). This meta-analysis indicated that HDR brachytherapy was a comparable alternative to LDR brachytherapy in treatment of oral cancer. HDR brachytherapy might become a routine choice for early-stage oral cancer in the future.

  10. Clinical evaluation in advanced practice nursing education: using standardized patients in Health Assessment.

    Science.gov (United States)

    Gibbons, Susanne W; Adamo, Graceanne; Padden, Diane; Ricciardi, Richard; Graziano, Marjorie; Levine, Eugene; Hawkins, Richard

    2002-05-01

    Clinical education is critically important because competency in practice ultimately will determine the future of advanced practice nursing. Skills taught in Health Assessment, the first in a series of clinical courses, exposed students to tools that form the basis on which other competencies are built. The availability of standardized patients, people who participate in enacting a simulated but seemingly "real life" clinical encounter in a realistic clinical setting for the benefit of student learning and/or evaluation, made this instructional development project possible. The underlying assumption of this project was that clinical advanced practice nursing student education is enhanced by using an authentic clinical environment, known as a simulation center, with standardized patients and by using one or more evaluation techniques with multiple evaluators (i.e., peer, self, faculty, standardized patient). The student clinical experience was expected to improve and overall learning to increase by this method. This improvement was reflected at the end-of-course evaluations and in the quality of the final videotaped physical examination, which was superior to previous years. Student and faculty satisfaction with this teaching-learning process exceeded all expectations.

  11. Intensity modulated radiation therapy (IMRT: differences in target volumes and improvement in clinically relevant doses to small bowel in rectal carcinoma

    Directory of Open Access Journals (Sweden)

    Delclos Marc E

    2011-06-01

    Full Text Available Abstract Background A strong dose-volume relationship exists between the amount of small bowel receiving low- to intermediate-doses of radiation and the rates of acute, severe gastrointestinal toxicity, principally diarrhea. There is considerable interest in the application of highly conformal treatment approaches, such as intensity-modulated radiation therapy (IMRT, to reduce dose to adjacent organs-at-risk in the treatment of carcinoma of the rectum. Therefore, we performed a comprehensive dosimetric evaluation of IMRT compared to 3-dimensional conformal radiation therapy (3DCRT in standard, preoperative treatment for rectal cancer. Methods Using RTOG consensus anorectal contouring guidelines, treatment volumes were generated for ten patients treated preoperatively at our institution for rectal carcinoma, with IMRT plans compared to plans derived from classic anatomic landmarks, as well as 3DCRT plans treating the RTOG consensus volume. The patients were all T3, were node-negative (N = 1 or node-positive (N = 9, and were planned to a total dose of 45-Gy. Pairwise comparisons were made between IMRT and 3DCRT plans with respect to dose-volume histogram parameters. Results IMRT plans had superior PTV coverage, dose homogeneity, and conformality in treatment of the gross disease and at-risk nodal volume, in comparison to 3DCRT. Additionally, in comparison to the 3DCRT plans, IMRT achieved a concomitant reduction in doses to the bowel (small bowel mean dose: 18.6-Gy IMRT versus 25.2-Gy 3DCRT; p = 0.005, bladder (V40Gy: 56.8% IMRT versus 75.4% 3DCRT; p = 0.005, pelvic bones (V40Gy: 47.0% IMRT versus 56.9% 3DCRT; p = 0.005, and femoral heads (V40Gy: 3.4% IMRT versus 9.1% 3DCRT; p = 0.005, with an improvement in absolute volumes of small bowel receiving dose levels known to induce clinically-relevant acute toxicity (small bowel V15Gy: 138-cc IMRT versus 157-cc 3DCRT; p = 0.005. We found that the IMRT treatment volumes were typically larger than that

  12. Randomized, Multicenter Trial on the Effect of Radiation Therapy on Plantar Fasciitis (Painful Heel Spur) Comparing a Standard Dose With a Very Low Dose: Mature Results After 12 Months' Follow-Up

    Energy Technology Data Exchange (ETDEWEB)

    Niewald, Marcus, E-mail: marcus.niewald@uks.eu [Department of Radiation Oncology, Saarland University Medical Center, Homburg/Saar (Germany); Seegenschmiedt, M. Heinrich [Radiotherapy Center, Hamburg (Germany); Micke, Oliver [Franziskus Hospital, Bielefeld (Germany); Graeber, Stefan [Institute for Medical Biometry, Epidemiology and Medical Informatics, Saarland University Medical Center, Homburg/Saar (Germany); Muecke, Ralf [Lippe Hospital, Lemgo (Germany); Schaefer, Vera; Scheid, Christine; Fleckenstein, Jochen; Licht, Norbert; Ruebe, Christian [Department of Radiation Oncology, Saarland University Medical Center, Homburg/Saar (Germany)

    2012-11-15

    Purpose: To conduct a randomized trial of radiation therapy for painful heel spur, comparing a standard dose with a very low dose. Methods and Materials: Sixty-six patients were randomized to receive radiation therapy either with a total dose of 6.0 Gy applied in 6 fractions of 1.0 Gy twice weekly (standard dose) or with a total dose of 0.6 Gy applied in 6 fractions of 0.1 Gy twice weekly (low dose). In all patients lateral opposing 4- to 6-MV photon beams were used. The results were measured using a visual analogue scale, the Calcaneodynia score, and the SF12 health survey. The fundamental phase of the study ended after 3 months, and the follow-up was continued up to 1 year. Patients with insufficient pain relief after 3 months were offered reirradiation with the standard dosage at any time afterward. Results: Of 66 patients, 4 were excluded because of withdrawal of consent or screening failures. After 3 months the results in the standard arm were highly significantly superior compared with those in the low-dose arm (visual analogue scale, P=.001; Calcaneodynia score, P=.027; SF12, P=.045). The accrual of patients was stopped at this point. Further evaluation after 12 months' follow-up showed the following results: (1) highly significant fewer patients were reirradiated in the standard arm compared with the low-dose arm (P<.001); (2) the results of patients in the low-dose arm who were reirradiated were identical to those in the standard arm not reirradiated (reirradiation as a salvage therapy if the lower dose was ineffective); (3) patients experiencing a favorable result after 3 months showed this even after 12 months, and some results even improved further between 3 and 12 months. Conclusions: This study confirms the superior analgesic effect of radiation therapy with 6-Gy doses on painful heel spur even for a longer time period of at least 1 year.

  13. Efficacy and safety of a booster dose of influenza vaccination in solid organ transplant recipients, TRANSGRIPE 1-2: study protocol for a multicenter, randomized, controlled clinical trial.

    Science.gov (United States)

    Martinez-Atienza, Juliana; Rosso-Fernández, Clara; Roca, Cristina; Aydillo, Teresa A; Gavaldà, Joan; Moreno, Asunción; Montejo, Jose M; Torre-Cisneros, Julian; Fariñas, M Carmen; Fortun, Jesus; Sabé, Nuria; Muñoz, Patricia; Blanes-Julia, Marino; Suárez-Benjumea, Alejandro; López-Medrano, Francisco; Pérez-Romero, Pilar; Cordero, Elisa

    2014-08-28

    Despite administration of annual influenza vaccination, influenza-associated complications in transplant recipients continue to be an important cause of hospitalization and death. Although influenza vaccination has been proven to be the most effective measure to reduce influenza infection after transplantation, transplant recipients are still vulnerable to influenza infections, with lower serological responses to vaccination compared to the general population. In order to assess the efficacy and safety of an alternative immunization scheme for solid organ transplant recipients, the TRANSGRIPE1-2 Study Group aimed to test a booster dose administration 5 weeks after the standard vaccination. The primary objective of this trial was to compare short-term and long-term neutralizing antibody immunogenicity of a booster dose of influenza vaccination to the standard single-dose immunization scheme. Secondary objectives included the evaluation of the efficacy and/or safety, cellular immune response, incidence of influenza infection, graft rejection, retransplant and mortality rates. This phase III, randomized, controlled, open-label clinical trial was conducted between October 2012 and December 2013 in 12 Spanish public referral hospitals. Solid organ transplant recipients (liver, kidney, heart or lung), older than 16 years of age more than 30 days after transplantation were eligible to participate. Patients (N = 514) were stratified 1:1 by center, type of organ and time after transplantation and who either received the standard single dose (n = 257) or were treated according to a novel influenza vaccination schedule comprising the administration of a booster dose 5 weeks after standard vaccination (n = 254). Seroconversion rates were measured as a determinant of protection against influenza (main outcome). Efficacy and safety outcomes were followed until 1 year after influenza vaccination with assessment of short-term (0, 5, 10 and 15 weeks) and long-term (12 months

  14. Multidetector CT radiation dose optimisation in adults: short- and long-term effects of a clinical audit.

    Science.gov (United States)

    Tack, Denis; Jahnen, Andreas; Kohler, Sarah; Harpes, Nico; De Maertelaer, Viviane; Back, Carlo; Gevenois, Pierre Alain

    2014-01-01

    To report short- and long-term effects of an audit process intended to optimise the radiation dose from multidetector row computed tomography (MDCT). A survey of radiation dose from all eight MDCT departments in the state of Luxembourg performed in 2007 served as baseline, and involved the most frequently imaged regions (head, sinus, cervical spine, thorax, abdomen, and lumbar spine). CT dose index volume (CTDIvol), dose-length product per acquisition (DLP/acq), and DLP per examination (DLP/exa) were recorded, and their mean, median, 25th and 75th percentiles compared. In 2008, an audit conducted in each department helped to optimise doses. In 2009 and 2010, two further surveys evaluated the audit's impact on the dose delivered. Between 2007 and 2009, DLP/exa significantly decreased by 32-69 % for all regions (P DRL) by 20-78 %. The audit process resulted in long-lasting dose reduction, with DRLs reduced by 20-78 %, mean DLP/examination by 18-75 %, and collective dose by 30 %. • External support through clinical audit may optimise default parameters of routine CT. • Reduction of 75th percentiles used as reference diagnostic levels is 18-75 %. • The effect of this audit is sustainable over time. • Dose savings through optimisation can be added to those achievable through CT.

  15. Standard-fractionated radiotherapy for optic nerve sheath meningioma: visual outcome is predicted by mean eye dose.

    Science.gov (United States)

    Abouaf, Lucie; Girard, Nicolas; Lefort, Thibaud; D'hombres, Anne; Tilikete, Caroline; Vighetto, Alain; Mornex, Françoise

    2012-03-01

    Radiotherapy has shown its efficacy in controlling optic nerve sheath meningiomas (ONSM) tumor growth while allowing visual acuity to improve or stabilize. However, radiation-induced toxicity may ultimately jeopardize the functional benefit. The purpose of this study was to identify predictive factors of poor visual outcome in patients receiving radiotherapy for ONSM. We conducted an extensive analysis of 10 patients with ONSM with regard to clinical, radiologic, and dosimetric aspects. All patients were treated with conformal radiotherapy and subsequently underwent biannual neuroophthalmologic and imaging assessments. Pretreatment and posttreatment values of visual acuity and visual field were compared with Wilcoxon's signed rank test. Visual acuity values significantly improved after radiotherapy. After a median follow-up time of 51 months, 6 patients had improved visual acuity, 4 patients had improved visual field, 1 patient was in stable condition, and 1 patient had deteriorated visual acuity and visual field. Tumor control rate was 100% at magnetic resonance imaging assessment. Visual acuity deterioration after radiotherapy was related to radiation-induced retinopathy in 2 patients and radiation-induced mature cataract in 1 patient. Study of radiotherapy parameters showed that the mean eye dose was significantly higher in those 3 patients who had deteriorated vision. Our study confirms that radiotherapy is efficient in treating ONSM. Long-term visual outcome may be compromised by radiation-induced side effects. Mean eye dose has to be considered as a limiting constraint in treatment planning. Copyright © 2012 Elsevier Inc. All rights reserved.

  16. Standard-Fractionated Radiotherapy for Optic Nerve Sheath Meningioma: Visual Outcome Is Predicted by Mean Eye Dose

    Energy Technology Data Exchange (ETDEWEB)

    Abouaf, Lucie [Neuro-Ophthalmology Unit, Pierre-Wertheimer Hospital, Hospices Civils de Lyon, Lyon (France); Girard, Nicolas [Radiotherapy-Oncology Department, Lyon Sud Hospital, Hospices Civils de Lyon, Lyon (France); Claude Bernard University, Lyon (France); Lefort, Thibaud [Neuro-Radiology Department, Pierre-Wertheimer Hospital, Hospices Civils de Lyon, Lyon (France); D' hombres, Anne [Claude Bernard University, Lyon (France); Tilikete, Caroline; Vighetto, Alain [Neuro-Ophthalmology Unit, Pierre-Wertheimer Hospital, Hospices Civils de Lyon, Lyon (France); Claude Bernard University, Lyon (France); Mornex, Francoise, E-mail: francoise.mornex@chu-lyon.fr [Claude Bernard University, Lyon (France)

    2012-03-01

    Purpose: Radiotherapy has shown its efficacy in controlling optic nerve sheath meningiomas (ONSM) tumor growth while allowing visual acuity to improve or stabilize. However, radiation-induced toxicity may ultimately jeopardize the functional benefit. The purpose of this study was to identify predictive factors of poor visual outcome in patients receiving radiotherapy for ONSM. Methods and Materials: We conducted an extensive analysis of 10 patients with ONSM with regard to clinical, radiologic, and dosimetric aspects. All patients were treated with conformal radiotherapy and subsequently underwent biannual neuroophthalmologic and imaging assessments. Pretreatment and posttreatment values of visual acuity and visual field were compared with Wilcoxon's signed rank test. Results: Visual acuity values significantly improved after radiotherapy. After a median follow-up time of 51 months, 6 patients had improved visual acuity, 4 patients had improved visual field, 1 patient was in stable condition, and 1 patient had deteriorated visual acuity and visual field. Tumor control rate was 100% at magnetic resonance imaging assessment. Visual acuity deterioration after radiotherapy was related to radiation-induced retinopathy in 2 patients and radiation-induced mature cataract in 1 patient. Study of radiotherapy parameters showed that the mean eye dose was significantly higher in those 3 patients who had deteriorated vision. Conclusions: Our study confirms that radiotherapy is efficient in treating ONSM. Long-term visual outcome may be compromised by radiation-induced side effects. Mean eye dose has to be considered as a limiting constraint in treatment planning.

  17. Methodological aspects of clinical trials in tinnitus: A proposal for an international standard

    Science.gov (United States)

    Landgrebe, Michael; Azevedo, Andréia; Baguley, David; Bauer, Carol; Cacace, Anthony; Coelho, Claudia; Dornhoffer, John; Figueiredo, Ricardo; Flor, Herta; Hajak, Goeran; van de Heyning, Paul; Hiller, Wolfgang; Khedr, Eman; Kleinjung, Tobias; Koller, Michael; Lainez, Jose Miguel; Londero, Alain; Martin, William H.; Mennemeier, Mark; Piccirillo, Jay; De Ridder, Dirk; Rupprecht, Rainer; Searchfield, Grant; Vanneste, Sven; Zeman, Florian; Langguth, Berthold

    2013-01-01

    Chronic tinnitus is a common condition with a high burden of disease. While many different treatments are used in clinical practice, the evidence for the efficacy of these treatments is low and the variance of treatment response between individuals is high. This is most likely due to the great heterogeneity of tinnitus with respect to clinical features as well as underlying pathophysiological mechanisms. There is a clear need to find effective treatment options in tinnitus, however, clinical trials differ substantially with respect to methodological quality and design. Consequently, the conclusions that can be derived from these studies are limited and jeopardize comparison between studies. Here, we discuss our view of the most important aspects of trial design in clinical studies in tinnitus and make suggestions for an international methodological standard in tinnitus trials. We hope that the proposed methodological standard will stimulate scientific discussion and will help to improve the quality of trials in tinnitus. PMID:22789414

  18. Providing support to nursing students in the clinical environment: a nursing standard requirement.

    Science.gov (United States)

    Anderson, Carina; Moxham, Lorna; Broadbent, Marc

    2016-10-01

    This discussion paper poses the question 'What enables or deters Registered Nurses to take up their professional responsibility to support undergraduate nursing students through the provision of clinical education?'. Embedded within many nursing standards are expectations that Registered Nurses provide support and professional development to undergraduate nursing students undertaking clinical placements. Expectations within nursing standards that Registered Nurses provide support and professional development to nursing students are important because nursing students depend on Registered Nurses to help them to become competent practitioners. Contributing factors that enable and deter Registered Nurses from fulfilling this expectation to support nursing students in their clinical learning include; workloads, preparedness for the teaching role, confidence in teaching and awareness of the competency requirement to support students. Factors exist which can enable or deter Registered Nurses from carrying out the licence requirement to provide clinical education and support to nursing students.

  19. [The challenges of standardization in clinical diagnostic laboratories of medical organizations].

    Science.gov (United States)

    Men'shikov, V V

    2013-04-01

    The generalized data concerning the conditions of application of regulations of national standards in clinical diagnostic laboratories of medical organizations is presented. The primary information was provided by 14 regions of 6 federal administrative okrugs of Russia. The causes of challenges of application of requirements of standards are presented. They are mostly related with insufficient financial support, lacking of manpower, difficulties with reagents supply, inadequate technical maintenance of devices and absence of support of administration of medical organizations. The recommendations are formulated concerning the necessity of publishing the document of Minzdrav of Russia to determine the need in application of standards in laboratory practice.

  20. Dose, duration and strain of bacillus Calmette-Guerin in the treatment of nonmuscle invasive bladder cancer: Meta-analysis of randomized clinical trials.

    Science.gov (United States)

    Quan, Yongjun; Jeong, Chang Wook; Kwak, Cheol; Kim, Hyeon Hoe; Kim, Hyung Suk; Ku, Ja Hyeon

    2017-10-01

    Intravesical bacillus Calmette-Guerin (BCG) instillation is widely used as an adjuvant therapy after transurethral resection of bladder tumor (TURBT) in patients with intermediate- and high-risk nonmuscle invasive bladder cancer (NMIBC). However, the effective dose, duration, and strain of BCG have not yet been clearly determined. We aimed to elucidate the relationship between dose, duration, and strain of BCG and clinical outcomes in NMIBC patients treated with TURBT. We conducted a literature search in Embase, Scopus, and PubMed databases for all relevant articles published up to October 2016 in accordance with the Preferred Reporting Items for Systematic Review and Meta-analysis guidelines. The relative risks of clinical outcomes, including recurrence, progression, cancer-specific mortality, and all-cause mortality according to dose (standard vs low), duration (induction vs maintenance), and strain of BCG were presented as the pooled risk ratio (RR) and 95% confidence interval (CI). Nineteen studies meeting the inclusion criteria were finally selected in this meta-analysis. The risk of recurrence was significantly highly observed in case of low-dose BCG (RR, 1.17; 95% CI 1.06-1.30) and induction BCG (RR, 1.33; 95% CI 1.17-1.50) only group without heterogeneity among the included studies. Although there were no significant differences between dose or duration and other clinical outcomes. On direct comparison in each study comparing BCG strains, the Tice stain showed a relatively high probability of recurrence compared with the Connaught (RR, 1.29; 95% CI 1.01-1.64) and RIVM (RR, 2.04, 95% CI 1.28-3.25) strains. Funnel plot testing revealed no significant publication bias. The use of standard dose and maintenance BCG instillation may be effective to reduce recurrence rate after TURBT for NMIBC. Further large scale, well-designed, and prospective studies, with stratification of the patients into risk group at randomization, will be required to determine the optimal

  1. Methadone dose in heroin-dependent patients: role of clinical factors, comedications, genetic polymorphisms and enzyme activity

    Science.gov (United States)

    Mouly, Stéphane; Bloch, Vanessa; Peoc'h, Katell; Houze, Pascal; Labat, Laurence; Ksouda, Kamilia; Simoneau, Guy; Declèves, Xavier; Bergmann, Jean Francois; Scherrmann, Jean-Michel; Laplanche, Jean-Louis; Lepine, Jean-Pierre; Vorspan, Florence

    2015-01-01

    Aims Methadone is characterized by wide intersubject variability regarding the dose needed to obtain full therapeutic response. We assessed the influence of sociodemographic, ethnic, clinical, metabolic and genotypic variables on methadone maintenance dose requirement in opioid-dependent responder patients. Methods Eighty-one stable patients (60 men and 21 women, 43.7 ± 8.1 years old, 63.1 ± 50.9 mg day−1 methadone), divided into quartiles with respect to the median daily dose, were enrolled and underwent clinical examination, treatment history and determination of liver/intestinal cytochrome P450 (CYP) 3A4 activity measured by the midazolam test, R,S-methadone trough concentration and clinically significant polymorphisms of the OPRM1, DRD2, COMT, ABCB1, CYP2B6, CYP3A5, CYP2C19 and CYP2D6 genes. Results Methadone maintenance dose was correlated to the highest dose ever used (r2 = 0.57, P methadone intake (odds ratio 4.87, 95% confidence interval 1.27–18.6, P = 0.02), bodyweight (odds ratio 1.57, 95% confidence interval 1.01–2.44, P = 0.04), history of cocaine dependence (80 vs. 44 mg day−1 in never-addict patients, P = 0.005) and ethnicity (Asian > Caucasian > African, P = 0.04) were independently associated with high-dose methadone in multiple regression analysis. A modest correlation was observed between liver/intestinal CYP3A4 activity and methadone dose at steady state (Spearman rank correlation coefficient [rs] = 0.21, P = 0.06) but not with highest dose ever used (rs = 0.15, P = 0.18) or dose-normalized R,S-methadone trough concentrations (rs = −0.05, P = 0.64). Concomitant CYP3A4 inhibitors only affected the relationship between methadone dose and R,S-methadone trough concentration. None of the genetic polymorphisms explored was predictive of the methadone maintenance dose. Conclusions Methadone maintenance dose was predicted by sociodemographic and clinical variables rather than genetic polymorphisms or liver/intestinal CYP3A4 activity in stable

  2. Call for standardized definitions of osteoarthritis and risk stratification for clinical trials and clinical use

    DEFF Research Database (Denmark)

    Kraus, V B; Blanco, F J; Englund, M

    2015-01-01

    Osteoarthritis (OA) is a heterogeneous disorder. The goals of this review are (1) To stimulate use of standardized nomenclature for OA that could serve as building blocks for describing OA and defining OA phenotypes, in short to provide unifying disease concepts for a heterogeneous disorder; and (2......) To stimulate establishment of ROAD (Risk of OA Development) and ROAP (Risk of OA Progression) tools analogous to the FRAX™ instrument for predicting risk of fracture in osteoporosis; and (3) To stimulate formulation of tools for identifying disease in its early preradiographic and/or molecular stages - REDI...... (Reliable Early Disease Identification). Consensus around more sensitive and specific diagnostic criteria for OA could spur development of disease modifying therapies for this entity that has proved so recalcitrant to date. We fully acknowledge that as we move forward, we expect to develop more...

  3. Call for standardized definitions of osteoarthritis and risk stratification for clinical trials and clinical use.

    Science.gov (United States)

    Kraus, V B; Blanco, F J; Englund, M; Karsdal, M A; Lohmander, L S

    2015-08-01

    Osteoarthritis (OA) is a heterogeneous disorder. The goals of this review are (1) To stimulate use of standardized nomenclature for OA that could serve as building blocks for describing OA and defining OA phenotypes, in short to provide unifying disease concepts for a heterogeneous disorder; and (2) To stimulate establishment of ROAD (Risk of OA Development) and ROAP (Risk of OA Progression) tools analogous to the FRAX™ instrument for predicting risk of fracture in osteoporosis; and (3) To stimulate formulation of tools for identifying disease in its early preradiographic and/or molecular stages - REDI (Reliable Early Disease Identification). Consensus around more sensitive and specific diagnostic criteria for OA could spur development of disease modifying therapies for this entity that has proved so recalcitrant to date. We fully acknowledge that as we move forward, we expect to develop more sophisticated definitions, terminology and tools. Copyright © 2015 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  4. Clinical indications and radiation doses to the conceptus associated with CT imaging in pregnancy: a retrospective study

    Energy Technology Data Exchange (ETDEWEB)

    Woussen, S.; Vanbeckevoort, D.; Bosmans, H.; Oyen, R. [University Hospitals Leuven, Department of Radiology, Leuven (Belgium); Lopez-Rendon, X.; Zanca, F. [University Hospitals Leuven, Department of Imaging and Pathology, Leuven (Belgium)

    2016-04-15

    To perform an internal audit at a university hospital with the aim of evaluating the number, clinical indication and operating procedure of computed tomography (CT) performed on pregnant patients and of estimating the radiation doses to the conceptus. A retrospective review was conducted of all CT examinations performed in a single centre on pregnant patients between January 2008 and July 2013. The radiation doses to the conceptus were estimated. The results were compared with published data. The number of CT examinations during pregnancy increased from 3-4 per year in 2008-2011 to 11 per year in 2012. The mean estimated conceptus radiation dose was considered negligible for CT of the head and cervical spine, being less than 0.01 mGy, and for CT of the chest, less than 0.1 mGy. The estimated conceptus radiation dose from abdominopelvic CT was on average 28.7 mGy (range 6.7-60.5 mGy). The number of CT scans of pregnant patients increased threefold during the last few years. Most clinical indications and doses were in line with good clinical practice and literature; only in two cases the dose to the conceptus was higher than 50 mGy. (orig.)

  5. Homework "Dose," Type, and Helpfulness as Predictors of Clinical Outcomes in Prolonged Exposure for PTSD.

    Science.gov (United States)

    Cooper, Andrew A; Kline, Alexander C; Graham, Belinda; Bedard-Gilligan, Michele; Mello, Patricia G; Feeny, Norah C; Zoellner, Lori A

    2017-03-01

    Homework is often viewed as central to prolonged exposure (PE) for posttraumatic stress disorder (PTSD), but its relationship with treatment outcome is not well understood. We evaluated homework type, dose, and patients' perceptions of helpfulness as predictors of symptom change and posttreatment outcomes in PE. Patients with chronic PTSD received PE in a randomized clinical trial. Independent evaluators assessed PTSD severity at pre- and posttreatment. Patients reported homework adherence and perceived helpfulness at the beginning of each session, separately for in vivo and imaginal exposure assignments. These variables were examined as predictors of change in PTSD symptoms, PTSD remission, and good end-state functioning (GESF; low PTSD, depression, and anxiety) at posttreatment. Higher imaginal homework adherence predicted greater symptom improvement between sessions and across treatment, as well as twice the odds of achieving remission and GESF. Patients who were at least moderately adherent to imaginal homework assignments (two or more times a week) reported more symptom gains than those who were least adherent but did not differ from those who were most adherent. In vivo adherence was not consistently associated with better outcome, perhaps due to heterogeneity in form and function of weekly assignments. Higher ratings of helpfulness of both types of homework predicted greater symptom improvement from pre- to posttreatment and between sessions. Overall, imaginal exposure homework may complement in-session exposures by enhancing key change processes, though perfect adherence is not necessary. Patients' perceptions of helpfulness may reflect buy-in or perceived match between homework completion and functional impairment. Clinically, in addition to targeting adherence to homework assignments, querying about perceived helpfulness and adjusting assignments appropriately may help augment clinical gains. Copyright © 2016. Published by Elsevier Ltd.

  6. Development of the 60Co gamma-ray standard field for therapy-level dosimeter calibration in terms of absorbed dose to water (ND,W)

    International Nuclear Information System (INIS)

    Fukumura, Akifumi; Mizuno, Hideyuki; Fukahori, Mai; Sakata, Suoh

    2013-01-01

    A primary standard for the absorbed dose rate to water in a 60 Co gamma-ray field was established at National Metrology Institute of Japan (NMIJ) in fiscal year 2011. Then, a 60 Co gamma-ray standard field for therapy-level dosimeter calibration in terms of absorbed dose to water was developed at National Institute of Radiological Sciences (NIRS) as a secondary standard dosimetry laboratory (SSDL). The results of an International Atomic Energy Agency (IAEA)/World Health Organization (WHO) TLD SSDL audit demonstrated that there was good agreement between NIRS stated absorbed dose to water and IAEA measurements. The IAEA guide based on the International Organization for Standardization (ISO) standard was used to estimate the relative expanded uncertainty of the calibration factor for a therapy-level Farmer type ionization chamber in terms of absorbed dose to water (N D,W ) with the new field. The uncertainty of N D,W was estimated to be 1.1% (k=2), which corresponds to approximately one third of the value determined in the existing air kerma field. The dissemination of traceability of the calibration factor determined in the new field is expected to diminish the uncertainty of dose delivered to patients significantly. (author)

  7. Clinically significant discrepancies between sleep problems assessed by standard clinical tools and actigraphy

    Directory of Open Access Journals (Sweden)

    Kjersti Marie Blytt

    2017-10-01

    Full Text Available Abstract Background Sleep disturbances are widespread among nursing home (NH patients and associated with numerous negative consequences. Identifying and treating them should therefore be of high clinical priority. No prior studies have investigated the degree to which sleep disturbances as detected by actigraphy and by the sleep-related items in the Cornell Scale for Depression in Dementia (CSDD and the Neuropsychiatric Inventory – Nursing Home version (NPI-NH provide comparable results. Such knowledge is highly needed, since both questionnaires are used in clinical settings and studies use the NPI-NH sleep item to measure sleep disturbances. For this reason, insight into their relative (disadvantages is valuable. Method Cross-sectional study of 83 NH patients. Sleep was objectively measured with actigraphy for 7 days, and rated by NH staff with the sleep items in the CSDD and the NPI-NH, and results were compared. McNemar's tests were conducted to investigate whether there were significant differences between the pairs of relevant measures. Cohen's Kappa tests were used to investigate the degree of agreement between the pairs of relevant actigraphy, NPI-NH and CSDD measures. Sensitivity and specificity analyses were conducted for each of the pairs, and receiver operating characteristics (ROC curves were designed as a plot of the true positive rate against the false positive rate for the diagnostic test. Results Proxy-raters reported sleep disturbances in 20.5% of patients assessed with NPI-NH and 18.1% (difficulty falling asleep, 43.4% (multiple awakenings and 3.6% (early morning awakenings of patients had sleep disturbances assessed with CSDD. Our results showed significant differences (p<0.001 between actigraphy measures and proxy-rated sleep by the NPI-NH and CSDD. Sensitivity and specificity analyses supported these results. Conclusions Compared to actigraphy, proxy-raters clearly underreported NH patients' sleep disturbances as assessed

  8. Quality standards for DNA sequence variation databases to improve clinical management under development in Australia

    Directory of Open Access Journals (Sweden)

    B. Bennetts

    2014-09-01

    Full Text Available Despite the routine nature of comparing sequence variations identified during clinical testing to database records, few databases meet quality requirements for clinical diagnostics. To address this issue, The Royal College of Pathologists of Australasia (RCPA in collaboration with the Human Genetics Society of Australasia (HGSA, and the Human Variome Project (HVP is developing standards for DNA sequence variation databases intended for use in the Australian clinical environment. The outputs of this project will be promoted to other health systems and accreditation bodies by the Human Variome Project to support the development of similar frameworks in other jurisdictions.

  9. Neuromuscular effect of dexmedetomidine on sevoflurane: an open-label, dose-escalation clinical trial.

    Science.gov (United States)

    Ke, Hui-Hua; Wu, Huang-Hui; Zhu, Qi; Zhang, Yan; Xiao, Jin-Rong; Su, Xiu-Zhu; Zheng, Wan-Jing; Cai, Yu-Ping; Wu, Xiao-Zhi; Wang, Yu-Tong; Chen, Guo-Zhong

    2017-08-01

    Sevoflurane presents reliable central neuromuscular effects. However, little knowledge is available regarding the interaction between sevoflurane and demedetomidine. We evaluated the neuromuscular effect of dexmedetomidine on sevoflurane in patients with normal neuromuscular transmission and calculated the 50% effective concentration (EC50). One-hundred and forty-four ASA grade I~II patients with normal neuromuscular transmission, aged 20~60 years old, undergoing lower limbs surgery were enrolled in this open-label, dose-escalation clinical trial. Patients were randomly assigned into 12 groups. Each patient received intravenous 0, 0.5, or 1.0 μg/kg dexmedetomidine 15 min after inhaling 0.7, 1.0, 1.4, or 2.0 MAC sevoflurane. Neuromuscular monitoring was recorded from the adductor pollicis muscle by using acceleromyography with train-of-four (TOF) stimulation of the ulnar nerve (2 Hz every 20 s). TOF ratio was recorded before inhaling sevoflurane, 15 min after keeping constant at target MAC of sevoflurane, 30 min after receiving target dose of dexmedetomidine, and 15 min after sevoflurane washing out. Sevoflurane produced a concentration-dependent decrease in TOF ratio. Mean TOF ratio in 0.7, 1.0, 1.4, and 2.0 MAC groups was 97.9%, 94.9%, 84.7%, and 77.2%, respectively. Neuromuscular EC50 of sevoflurane was 1.31 MAC (95% CI: 1.236~1.388 MAC). Intravenous 0.5 and 1.0 μg/kg dexmedetomidine decreased 3.1% (EC50: 1.27 MAC [95% CI: 1.206~1.327 MAC]) and 10.7% (EC50: 1.17 MAC [95% CI: 1.122~1.217 MAC]) of neuromuscular EC50, respectively. Sevoflurane has a concentration-dependent central neuromuscular effect in patients with normal neuromuscular transmission. Intravenous dexmedetomidine dose-dependently decreases the neuromuscular EC50 of sevoflurane.

  10. An automated standardized system for managing adverse events in clinical research networks.

    Science.gov (United States)

    Richesson, Rachel L; Malloy, Jamie F; Paulus, Kathleen; Cuthbertson, David; Krischer, Jeffrey P

    2008-01-01

    Multi-site clinical protocols and clinical research networks require tools to manage and monitor adverse events (AEs). To be successful, these tools must be designed to comply with applicable regulatory requirements, reflect current data standards, international directives and advances in pharmacovigilance, and be convenient and adaptable to multiple needs. We describe an Adverse Event Data Management System (AEDAMS) that is used across multiple study designs in the various clinical research networks and multi-site studies for which we provide data and technological support. Investigators enter AE data using a standardized and structured web-based data collection form. The automated AEDAMS forwards the AE information to individuals in designated roles (investigators, sponsors, Data Safety and Monitoring Boards) and manages subsequent communications in real time, as the entire reporting, review and notification is done by automatically generated emails. The system was designed to adhere to timelines and data requirements in compliance with Good Clinical Practice (International Conference on Harmonisation E6) reporting standards and US federal regulations, and can be configured to support AE management for many types of study designs and adhere to various domestic or international reporting requirements. This tool allows AEs to be collected in a standard way by multiple distributed users, facilitates accurate and timely AE reporting and reviews, and allows the centralized management of AEs. Our design justification and experience with the system are described.

  11. European AIDS Clinical Society Standard of Care meeting on HIV and related coinfections: The Rome Statements

    NARCIS (Netherlands)

    Mussini, C.; Antinori, A.; Bhagani, S.; Branco, T.; Brostrom, M.; Dedes, N.; Bereczky, T.; Girardi, E.; Gökengin, D.; Horban, A.; Lacombe, K.; Lundgren, J. D.; Mendao, L.; Mocroft, A.; Oprea, C.; Porter, K.; Podlekareva, D.; Battegay, M.; d'Arminio Monforte, A.; Mulcahy, Fiona; Geretti, Anna Maria; Clumeck, Nathan; Reiss, Peter; Arribas, Jose; Gatell, Jose; Katlama, Christine; Pozniak, Anton; Rockstroh, Jürgen; Youle, Mike; Friis-Møller, Nina; Rusconi, Stefano; Behrens, Georg; de Wit, Stéphane; Furrer, Hansjakob; Wensing, Annemarie; John Gill, M.; Letendre, Scott

    2016-01-01

    The objective of the 1st European AIDS Clinical Society meeting on Standard of Care in Europe was to raise awareness of the European scenario and come to an agreement on actions that could be taken in the future. Data-driven presentations were given on specific topics followed by interactive panel

  12. European AIDS Clinical Society Standard of Care meeting on HIV and related coinfections : The Rome Statements

    NARCIS (Netherlands)

    Mussini, C.; Antinori, A.; Bhagani, S.; Branco, T.; Brostrom, M.; Dedes, N.; Bereczky, T.; Girardi, E.; Gökengin, D.; Horban, A.; Lacombe, K.; Lundgren, J. D.; Mendao, L.; Mocroft, A.; Oprea, C.; Porter, K.; Podlekareva, D.; Battegay, M.; d'Arminio Monforte, A.; Mulcahy, Fiona; Geretti, Anna Maria; Clumeck, Nathan; Reiss, Peter; Arribas, Jose; Gatell, Jose; Katlama, Christine; Pozniak, Anton; Rockstroh, Jürgen; Youle, Mike; Friis-Møller, Nina; Rusconi, Stefano; Behrens, Georg; De Wit, Stéphane; Furrer, Hansjakob; Wensing, Annemarie|info:eu-repo/dai/nl/30817724X; John Gill, M.; Letendre, Scott

    2016-01-01

    Objectives: The objective of the 1st European AIDS Clinical Society meeting on Standard of Care in Europe was to raise awareness of the European scenario and come to an agreement on actions that could be taken in the future. Methods: Data-driven presentations were given on specific topics followed

  13. Standardized Patient Encounters Improved Athletic Training Students' Confidence in Clinical Evaluations

    Science.gov (United States)

    Armstrong, Kirk J.; Jarriel, Amanda J.

    2015-01-01

    Context: Researchers have reported that interacting with standardized patients (SPs) is a worthwhile and realistic experience for athletic training (AT) students. These encounters enhance students' interviewing skills, confidence as a clinician, clinical skill development, and interpersonal communication. Objective: To determine how SP encounters…

  14. European AIDS Clinical Society Second Standard of Care Meeting, Brussels 16-17 November 2016

    DEFF Research Database (Denmark)

    De Wit, S; Battegay, M; D'Arminio Monforte, A

    2018-01-01

    The European AIDS Clinical Society (EACS) organized a second meeting on Standard of Care in Europe on November 16-17 th, 2016. The aims of the meeting were to discuss and propose actions on three topics, namely: Adherence to guidelines for treatment initiation, treatment monitoring and outcomes, ...

  15. Clinical evaluation of the partition model for estimating radiation doses from yttrium-90 microspheres in the treatment of hepatic cancer

    International Nuclear Information System (INIS)

    Ho, S.; Lau, W.Y.; Leung, T.W.T.; Chan, M.; Johnson, P.J.; Li, A.K.C.

    1997-01-01

    Radiation doses to the tumour and non-tumorous liver compartments from yttrium-90 microspheres in the treatment of hepatic cancer, as estimated by a partition model, have been verified by correlation with the actual doses measured with a beta probe at open surgery. The validity of the doses to the lungs, the tumour and non-tumours liver compartment as estimated by the partition model was further evaluated in clinical settings. On the basis of the observation that one of three patients who received more than 30 Gy from a single treatment and one of two patients who received more than 50 Gy from multiple treatments developed radiation pneumonitis, it was deduced that an estimated lung dose 30 Gy as estimated by the partition model and were predicted to develop radiation pneumonitis, did so despite the use of partial hepatic embolization to reduce the degree of lung shunting. Furthermore, a higher radiological response rate and prolonged survival were found in the group of patients who received higher tumour doses, as estimated by the partition model, than in the group with lower estimated tumour doses. Thus the radiation doses estimated by the partition model can be used to predict (a) complication rate, (b) response rate and (c) duration of survival in the same manner as the actual radiation doses measured with a beta probe at open surgery. The partition model has made selective internal radiation therapy using 90 Y microspheres safe and repeatable without laparotomy. (orig.)

  16. SINGLE-DOSE VERSUS 3-DAY PROPHYLAXIS WITH CIPROFLOXACIN IN TRANSURETHRAL SURGERY - A CLINICAL-TRIAL

    NARCIS (Netherlands)

    BIJL, W; JANKNEGT, RA

    1993-01-01

    in 235 patients who underwent transurethral surgery, perioperative oral ciprofloxacin prophylaxis was given as a single dose 500 mg versus a 3-day regimen. Out of 180 evaluable patients, 84 received a single dose and 96 received a 3-day course. In the single dose prophylaxis group there were 5

  17. Dosing anticancer drugs in infants: Current approach and recommendations from the Children's Oncology Group's Chemotherapy Standardization Task Force.

    Science.gov (United States)

    Balis, Frank M; Womer, Richard B; Berg, Stacey; Winick, Naomi; Adamson, Peter C; Fox, Elizabeth

    2017-11-01

    An analysis of dose modifications for infants in 29 Children's Oncology Group protocols across 10 cancer types revealed 11 sets of criteria defining the infant population using age, weight, body surface area (BSA), or a combination of these parameters and eight dose modification methods. A new method of dosing anticancer drugs in infants was developed based on the rationale that prior modifications were implemented to reduce toxicity, which is not cancer-specific. The new method uses BSA dose banding in dosing tables for infants and children with a BSA <0.6 m 2 and gradually transitions from body weight based to BSA-based dosing. © 2017 Wiley Periodicals, Inc.

  18. Can a standard dose of eicosapentaenoic acid (EPA supplementation reduce the symptoms of delayed onset of muscle soreness?

    Directory of Open Access Journals (Sweden)

    Houghton David

    2012-01-01

    Full Text Available Abstract Background Unaccustomed exercise can result in delayed onset of muscle soreness (DOMS which can affect athletic performance. Although DOMS is a useful tool to identify muscle damage and remodelling, prolonged symptoms of DOMS may be associated with the over-training syndrome. In order to reduce the symptoms of DOMS numerous management strategies have been attempted with no significant effect on DOMS-associated cytokines surge. The present study aimed to investigate the acute and chronic effects of a 2 × 180 mg per day dose of eicosapentaenoic acid (EPA on interleukin-6 (IL-6 mediated inflammatory response and symptoms associated with DOMS. Methods Seventeen healthy non-smoking females (age 20.4 ± 2.1 years, height 161.2 ± 8.3 cm and mass 61.48 ± 7.4 kg were randomly assigned to either placebo (N = 10 or EPA (N = 7. Serum IL-6, isometric and isokinetic (concentric and eccentric strength, and rating of perceived exertion (RPE were recorded on four occasions: i-prior to supplementation, ii-immediately after three weeks of supplementation (basal effects, iii-48 hours following a single bout of resistance exercise (acute training response effects, and iv-48 hours following the last of a series of three bouts of resistance exercise (chronic training response effects. Results There was only a group difference in the degree of change in circulating IL-6 levels. In fact, relative to the first baseline, by the third bout of eccentric workout, the EPA group had 103 ± 60% increment in IL-6 levels whereas the placebo group only had 80 ± 26% incremented IL-6 levels (P = 0.020. We also describe a stable multiple linear regression model which included measures of strength and not IL-6 as predictors of RPE scale. Conclusion The present study suggests that in doubling the standard recommended dose of EPA, whilst this may still not be beneficial at ameliorating the symptoms of DOMS, it counter intuitively appears to enhance the cytokine response to

  19. Clinical pharmacokinetics and pharmacodynamic target attainment of pazufloxacin in prostate tissue: Dosing considerations for prostatitis.

    Science.gov (United States)

    Nakamura, Kogenta; Ikawa, Kazuro; Nishikawa, Genya; Kobayashi, Ikuo; Narushima, Masahiro; Muramatsu, Hiroyuki; Morinaga, Shingo; Kajikawa, Keishi; Kato, Yoshiharu; Watanabe, Masahito; Zennami, Kenji; Kanao, Kent; Morikawa, Norifumi; Sumitomo, Makoto

    2017-12-01

    The present study examined the clinical pharmacokinetics of pazufloxacin in prostate tissue and estimated the probability of target attainment for tissue-specific pharmacodynamic goals related to treating prostatitis using various intravenous dosing regimens. Patients with prostatic hypertrophy received prophylactic infusions of pazufloxacin (500 mg, n = 23; 1000 mg, n = 25) for 0.5 h prior to transurethral prostate resection. Drug concentrations in plasma (0.5-5 h) and prostate tissue (0.5-1.5 h) were measured by high-performance liquid chromatography and used for subsequent noncompartmental and three-compartmental analysis. Monte Carlo simulation was performed to evaluate the probability of target attainment of a specific minimum inhibitory concentration (MIC) in prostate tissue: the proportion that achieved both area under the drug concentration over time curve (AUC)/MIC = 100 and maximum concentration (C max )/MIC = 8. Prostatic penetration of pazufloxacin was good with mean C max ratios (prostate tissue/plasma) of 0.82-0.99 and for AUC, 0.80-0.98. The probability of reaching target MIC concentrations in prostate tissue was more than 90% for dosing schedules of 0.25 mg/L for 500 mg every 24 h (500 mg daily), 0.5 mg/L for 500 mg every 12 h (1000 mg daily), 1 mg/L for 1000 mg every 24 h (1000 mg daily), and 2 mg/L for 1000 mg every 12 h (2000 mg daily). Importantly, the 2000 mg daily regimen of pazufloxacin produced a profile sufficient to have an antibacterial effect in prostate tissue against clinical isolates of Escherichia coli and Klebsiella pneumonia with MIC values less than 2 mg/L. Copyright © 2017 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  20. Continual reassessment method for dose escalation clinical trials in oncology: a comparison of prior skeleton approaches using AZD3514 data.

    Science.gov (United States)

    James, Gareth D; Symeonides, Stefan N; Marshall, Jayne; Young, Julia; Clack, Glen

    2016-08-31

    The continual reassessment method (CRM) requires an underlying model of the dose-toxicity relationship ("prior skeleton") and there is limited guidance of what this should be when little is known about this association. In this manuscript the impact of applying the CRM with different prior skeleton approaches and the 3 + 3 method are compared in terms of ability to determine the true maximum tolerated dose (MTD) and number of patients allocated to sub-optimal and toxic doses. Post-hoc dose-escalation analyses on real-life clinical trial data on an early oncology compound (AZD3514), using the 3 + 3 method and CRM using six different prior skeleton approaches. All methods correctly identified the true MTD. The 3 + 3 method allocated six patients to both sub-optimal and toxic doses. All CRM approaches allocated four patients to sub-optimal doses. No patients were allocated to toxic doses from sigmoidal, two from conservative and five from other approaches. Prior skeletons for the CRM for phase 1 clinical trials are proposed in this manuscript and applied to a real clinical trial dataset. Highly accurate initial skeleton estimates may not be essential to determine the true MTD, and, as expected, all CRM methods out-performed the 3 + 3 method. There were differences in performance between skeletons. The choice of skeleton should depend on whether minimizing the number of patients allocated to suboptimal or toxic doses is more important. NCT01162395 , Trial date of first registration: July 13, 2010.

  1. Spot scanning proton therapy plan assessment: design and development of a dose verification application for use in routine clinical practice

    Science.gov (United States)

    Augustine, Kurt E.; Walsh, Timothy J.; Beltran, Chris J.; Stoker, Joshua B.; Mundy, Daniel W.; Parry, Mark D.; Bues, Martin; Fatyga, Mirek

    2016-04-01

    The use of radiation therapy for the treatment of cancer has been carried out clinically since the late 1800's. Early on however, it was discovered that a radiation dose sufficient to destroy cancer cells can also cause severe injury to surrounding healthy tissue. Radiation oncologists continually strive to find the perfect balance between a dose high enough to destroy the cancer and one that avoids damage to healthy organs. Spot scanning or "pencil beam" proton radiotherapy offers another option to improve on this. Unlike traditional photon therapy, proton beams stop in the target tissue, thus better sparing all organs beyond the targeted tumor. In addition, the beams are far narrower and thus can be more precisely "painted" onto the tumor, avoiding exposure to surrounding healthy tissue. To safely treat patients with proton beam radiotherapy, dose verification should be carried out for each plan prior to treatment. Proton dose verification systems are not currently commercially available so the Department of Radiation Oncology at the Mayo Clinic developed its own, called DOSeCHECK, which offers two distinct dose simulation methods: GPU-based Monte Carlo and CPU-based analytical. The three major components of the system include the web-based user interface, the Linux-based dose verification simulation engines, and the supporting services and components. The architecture integrates multiple applications, libraries, platforms, programming languages, and communication protocols and was successfully deployed in time for Mayo Clinic's first proton beam therapy patient. Having a simple, efficient application for dose verification greatly reduces staff workload and provides additional quality assurance, ultimately improving patient safety.

  2. College of American Pathologists' laboratory standards for next-generation sequencing clinical tests.

    Science.gov (United States)

    Aziz, Nazneen; Zhao, Qin; Bry, Lynn; Driscoll, Denise K; Funke, Birgit; Gibson, Jane S; Grody, Wayne W; Hegde, Madhuri R; Hoeltge, Gerald A; Leonard, Debra G B; Merker, Jason D; Nagarajan, Rakesh; Palicki, Linda A; Robetorye, Ryan S; Schrijver, Iris; Weck, Karen E; Voelkerding, Karl V

    2015-04-01

    The higher throughput and lower per-base cost of next-generation sequencing (NGS) as compared to Sanger sequencing has led to its rapid adoption in clinical testing. The number of laboratories offering NGS-based tests has also grown considerably in the past few years, despite the fact that specific Clinical Laboratory Improvement Amendments of 1988/College of American Pathologists (CAP) laboratory standards had not yet been developed to regulate this technology. To develop a checklist for clinical testing using NGS technology that sets standards for the analytic wet bench process and for bioinformatics or "dry bench" analyses. As NGS-based clinical tests are new to diagnostic testing and are of much greater complexity than traditional Sanger sequencing-based tests, there is an urgent need to develop new regulatory standards for laboratories offering these tests. To develop the necessary regulatory framework for NGS and to facilitate appropriate adoption of this technology for clinical testing, CAP formed a committee in 2011, the NGS Work Group, to deliberate upon the contents to be included in the checklist. Results . -A total of 18 laboratory accreditation checklist requirements for the analytic wet bench process and bioinformatics analysis processes have been included within CAP's molecular pathology checklist (MOL). This report describes the important issues considered by the CAP committee during the development of the new checklist requirements, which address documentation, validation, quality assurance, confirmatory testing, exception logs, monitoring of upgrades, variant interpretation and reporting, incidental findings, data storage, version traceability, and data transfer confidentiality.

  3. Certifying a university ENT clinic using the ISO 9001:2000 international standard.

    Science.gov (United States)

    Helbig, Matthias; Helbig, Silke; Kahla-Witzsch, Heike A; Kroll, Tobias; May, Angelika

    2010-01-01

    Against statutory duties to introduce quality management systems, the increased importance of this subject has led to numerous activities in various public health institutions. Following the International Standardization Organization (ISO 9001:2000) prerequisites, Frankfurt Goethe University Hospital ENT clinic staff introduced a quality management system. This paper aims to investigate this process. Designing, planning and implementing the quality management system is described. Under the supervision of an executive quality management board, clinic quality goals were defined. Thereafter, several quality management teams performed an actual state analysis as well as developing and realising improvement proposals. Finally a quality management manual containing binding standards and working instructions concerning all patient care, research and teaching aspects was written. Successful certification by a neutral body ascertained that the clinic's quality management system conformed to current national and international standards while restructuring and reform improved procedural efficiency. The paper shows that mplementing the quality management system requires considerable effort but patients as well as staff profit considerably from the innovation. On the whole, the positive impact on structure and workflow in a specialist clinic predominates. Therefore, implementing a quality management system in all the clinic's wards and departments is recommended.

  4. A scheme for the audit of scientific and technological standards in clinical nuclear medicine

    International Nuclear Information System (INIS)

    Perkins, A.C.; Jarritt, P.H.

    2002-01-01

    Aim: Audit is the process whereby the quality of a service is monitored and optimised. It forms an essential component of the quality assurance process, whether by self-assessment or by external peer review. In the UK the British Nuclear Medicine Society (BNMS) has undertaken external organisational audit of departments providing clinical nuclear medicine services. This work aimed to develop a more thorough and service specific process for the audit of scientific and technological standards in nuclear medicine. Materials and Methods: The audit process has been implemented using written audit documents to facilitate the audit procedure. A questionnaire forms part of the formal documentation for audit of the scientific and technical standards of a clinical service. Scientific and technical standards were derived from a number of sources including legal requirements, regulatory obligations, notes for guidance, peer reviewed publications and accepted good clinical practice (GCP). Results: The audit process graded the standards of an individual department according to legal or safety requirements (Grade A), good practice (Grade B) and desirable aspects of service delivery (Grade C). The standards have been allocated into eight main categories. These are: Instrumentation; Software and data protection; Electrical Safety; Mechanical Safety; Workstation Safety; The Control of Substances Hazardous to Health (COSHH); Radiation Protection; Scientific and Technical staffing levels. During the audit visit a detailed inspection of clinical and laboratory areas and department written documentation is also necessary to validate the data obtained. Conclusion: The printed scheme now provides a means for external audit or self-assessment. There should be evidence of a well-organised and safe environment for both patients and staff. Health and Safety legislation requires written local rules and these records should be available to demonstrate the standard of service provision. Other

  5. Current practices and challenges in the standardization and harmonization of clinical laboratory tests123

    Science.gov (United States)

    Vesper, Hubert W; Myers, Gary L; Miller, W Greg

    2016-01-01

    Effective patient care, clinical research, and public health efforts require comparability of laboratory results independent of time, place, and measurement procedure. Comparability is achieved by establishing metrological traceability, which ensures that measurement procedures measure the same quantity and that the calibration of measurement procedures is traceable to a common reference system consisting of reference methods and materials. Whereas standardization ensures traceability to the International System of Units, harmonization ensures traceability to a reference system agreed on by convention. This article provides an overview of standardization and harmonization with an emphasis on commutability as an important variable that affects testing accuracy. Commutability of reference materials is required to ensure that traceability is established appropriately and that laboratory results are comparable. The use of noncommutable reference materials leads to inaccurate results. Whereas procedures and protocols for standardizing measurements are established and have been successfully applied in efforts such as the Hormones Standardization Program of the CDC, harmonization activities require new, more complex procedures and approaches. The American Association for Clinical Chemistry, together with its domestic and international partners, formed the International Consortium for Harmonization of Clinical Laboratory Results to coordinate harmonization efforts. Reference systems, as well as procedures and protocols to establish traceability of clinical laboratory tests, have been established and continue to be developed by national and international groups and organizations. Serum tests of thyroid function, including those for the thyroid hormones thyroxine and triiodothyronine, are among the clinical procedures for which standardization efforts are well under way. Approaches to the harmonization of measurement procedures for serum concentrations of thyroid

  6. SU-E-T-783: Using Matrixx to Determine Transit Dose Contribution Over Clinically Useful Limits of HDR Source Activity

    International Nuclear Information System (INIS)

    Bhagwat, M; O’Farrell, D; Wagar, M; Buzurovic, I; Friesen, S; Damato, A; Devlin, P; Cormack, R

    2015-01-01

    Purpose: Most HDR brachytherapy treatment planning systems (TPS) use TG-43 formalism to calculate dose without including transit dose corrections. Historically, measurement of this contribution has required sophisticated apparatus unavailable in most hospitals. We use Matrixx to investigate several scenarios where transit dose contribution may effect a clinical treatment. Methods: Treatment plans were generated using Oncentra Brachy TPS (Version 4.3.0.410, Nucletron ) on a CT scan of a 24-catheter Freiburg applicator (Nucletron ) laid flat on the MatriXX (IBA) detector. This detector is an array of 1020 parallel plate ion chambers. All 24 catheters were digitized and dwells within a central square region of 5×5cm of the applicator were activated. Each of the active catheters had 6 dwells in increments of 1.0cm. The plans were normalized to 10mm. This places the 100% isodose line at the correct effective point of measurement, which lies half-way between the parallel plates of the ion chambers. It is also within the clinically relevant treatment depth for superficial applications. A total of 6 plans were delivered for 3 prescription doses, 1Gy, 2Gy and 4Gy using source activities of 2.9Ci and 11.2Ci. The MatriXX array was operated to capture dosimetric snaps every 500ms and yielded an integral dose at the end of treatment. Results: A comparison of integral dose from 2 different source activities shows that the transit dose contribution is larger when the source activity is higher. It is also observed that the relative transit dose contribution decreases as prescription dose increases. This is quantified by the Gamma analysis. Conclusion: We have demonstrated that the Matrixx detector can be used to evaluate the contribution for a HDR source during transit from the HDR afterloader to a dwell location, and between adjacent dwell locations

  7. SU-E-T-783: Using Matrixx to Determine Transit Dose Contribution Over Clinically Useful Limits of HDR Source Activity

    Energy Technology Data Exchange (ETDEWEB)

    Bhagwat, M; O’Farrell, D; Wagar, M; Buzurovic, I; Friesen, S; Damato, A; Devlin, P; Cormack, R [Dana-Farber Brigham and Women’s Cancer Center, Harvard Medical School, Boston, MA (United States)

    2015-06-15

    Purpose: Most HDR brachytherapy treatment planning systems (TPS) use TG-43 formalism to calculate dose without including transit dose corrections. Historically, measurement of this contribution has required sophisticated apparatus unavailable in most hospitals. We use Matrixx to investigate several scenarios where transit dose contribution may effect a clinical treatment. Methods: Treatment plans were generated using Oncentra Brachy TPS (Version 4.3.0.410, Nucletron ) on a CT scan of a 24-catheter Freiburg applicator (Nucletron ) laid flat on the MatriXX (IBA) detector. This detector is an array of 1020 parallel plate ion chambers. All 24 catheters were digitized and dwells within a central square region of 5×5cm of the applicator were activated. Each of the active catheters had 6 dwells in increments of 1.0cm. The plans were normalized to 10mm. This places the 100% isodose line at the correct effective point of measurement, which lies half-way between the parallel plates of the ion chambers. It is also within the clinically relevant treatment depth for superficial applications. A total of 6 plans were delivered for 3 prescription doses, 1Gy, 2Gy and 4Gy using source activities of 2.9Ci and 11.2Ci. The MatriXX array was operated to capture dosimetric snaps every 500ms and yielded an integral dose at the end of treatment. Results: A comparison of integral dose from 2 different source activities shows that the transit dose contribution is larger when the source activity is higher. It is also observed that the relative transit dose contribution decreases as prescription dose increases. This is quantified by the Gamma analysis. Conclusion: We have demonstrated that the Matrixx detector can be used to evaluate the contribution for a HDR source during transit from the HDR afterloader to a dwell location, and between adjacent dwell locations.

  8. Dual trigger with gonadotropin-releasing hormone agonist and standard dose human chorionic gonadotropin to improve oocyte maturity rates.

    Science.gov (United States)

    Griffin, Daniel; Feinn, Richard; Engmann, Lawrence; Nulsen, John; Budinetz, Tara; Benadiva, Claudio

    2014-08-01

    To evaluate the percentage (%) of mature oocytes retrieved in patients with a previous history of >25% immature oocytes retrieved who were triggered with gonadotropin-releasing hormone agonist (GnRH-a) and human chorionic gonadotropin (hCG) to induce oocyte maturation. Retrospective cohort study. A university-based tertiary fertility center. Patients with a history of >25% immature oocytes retrieved in a prior in vitro fertilization cycle who were triggered with GnRH-a and hCG 5,000 IU or 10,000 IU in a subsequent cycle from January 2008 through February 2012. Dual trigger of GnRH-a and hCG 5,000 or 10,000 IU. Percent of mature oocytes retrieved and fertilization rate. The proportion of mature oocytes retrieved was significantly higher with a dual trigger compared with the subject's previous cycle (75.0%, interquartile range 55.6%-80.0% vs. 38.5%, interquartile range 16.7%-55.6%). The odds of a mature oocyte retrieved for patients who received a dual trigger was 2.51 times higher after controlling for stimulation protocol, hCG dose, gonadotropin dose, and oocyte retrieval time interval (odds ratio 2.51; confidence interval 1.06-5.96). The implantation, clinical, and ongoing pregnancy rates for the dual trigger were 11.8%, 26.1%, and 17.4%, respectively. In patients with a low percentage of mature oocytes retrieved who are triggered with a combination of GnRH-a and hCG, the % of mature oocytes retrieved improved. in vitro fertilization outcomes, however, remain poor, suggesting an underlying oocyte dysfunction. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  9. Clinical Strategy for Optimal Traditional Chinese Medicine (TCM) Herbal Dose Selection in Disease Therapeutics: Expert Consensus on Classic TCM Herbal Formula Dose Conversion.

    Science.gov (United States)

    Zha, Lin-Hua; He, Li-Sha; Lian, Feng-Mei; Zhen, Zhong; Ji, Hang-Yu; Xu, Li-Peng; Tong, Xiao-Lin

    2015-01-01

    The clinical therapeutics of traditional Chinese medicine (TCM) constitutes a complicated process which involves theory, diagnosis, and formula prescription with specific herbal dosage. Zhang Zhong-Jing's classic work, Treatise on Febrile and Miscellaneous Diseases, has been influencing TCM practice for almost 2000 years. However, during this extended period of time in Chinese history, the Chinese weight measurement system experienced noticeable changes. This change in the weight measurement system inevitably, and perhaps even negatively, affected TCM herbal dosage determination and treatment outcome. Thus, in modern society, a full understanding of the accuracy of herbal dose selection has a critical importance in the TCM daily practice of delivering the best treatment to the patients suffering from different illnesses. In the 973 Project of the Chinese National Basic Research Program, expert consensus on classic TCM formula dose conversion has been reached based on extensive literature review and discussion on the dose-effect relationship of classic TCM formulas. One "liang" in classic TCM formulas is equivalent to 13.8 g. However, based on many TCM basic and clinical studies of variable herbal formula prescriptions and herbal drug preparations, the rule of one liang equals 13.8 g should be adjusted according to different disease conditions. Recommended by the committee on TCM formula dose-effect relationship of the China Association of Chinese Medicine and the World Federation of Chinese Medicine Societies, the following expert consensus has been reached: (i) One liang converts to 6-9 g for the severely and critically ill patients. (ii) One liang converts to 3-6 g for the patients suffering from chronic diseases. (iii) One liang converts to 1-3 g in preventive medicine. The above conversions should be used as a future TCM practice guideline. Using this recommended guideline should enhance the effectiveness of daily TCM practice.

  10. Fixed ratio dosing of pramlintide with regular insulin before a standard meal in patients with type 1 diabetes.

    Science.gov (United States)

    Riddle, M C; Yuen, K C J; de Bruin, T W; Herrmann, K; Xu, J; Öhman, P; Kolterman, O G

    2015-09-01

    Amylin is co-secreted with insulin and is therefore lacking in patients with type 1 diabetes. Replacement with fixed ratio co-administration of insulin and the amylin analogue pramlintide may be superior to separate dosing. This concept was evaluated in a ratio-finding study. Patients with type 1 diabetes were enrolled in a randomized, single-masked, standard breakfast crossover study using regular human insulin injected simultaneously with pramlintide 6, 9 or 12 mcg/unit insulin or placebo. Insulin dosage was reduced by 30% from patients' usual estimates. Plasma glucose, glucagon and pramlintide and adverse events were assessed. All ratios reduced 0-3-h glucose and glucagon increments by >50%. No hypoglycaemia occurred. Adverse events were infrequent and generally mild. All pramlintide/insulin ratios markedly and safely reduced glycaemic excursions and suppressed glucagon secretion in the immediate postprandial state. Further study using one of these ratios to explore the efficacy and safety of longer-term meal-time and basal hormone replacement is warranted. © 2015 The Authors. Diabetes, Obesity and Metabolism published by John Wiley & Sons Ltd.

  11. Dose management as a measurable criteria into the quality control programme of an imaging diagnostic clinic

    International Nuclear Information System (INIS)

    Kirova, G.; Georgiev, E.; Zasheva, C.; Georgiev, S.

    2014-01-01

    In the Radiology Department of Tokuda Hospital Sofia, a strong control over the radiation dose for all patients was accepted with the implementation of the Dose Watch software. The system allows bad practices to be discovered and improves the efficiency and quality of the CT procedures performed in the department. The article will briefly demonstrate the main steps, which have been done, and the results, which have been achieved. The purpose is to identify the challenges, the available tools, and the opportunities for improving the patients' dose in the CT sector of a general Radiology Department. Collected data was based on the information concerning the radiation dose absorbed by individual patients undergoing MDCT examinations in a general radiology department with an overall annual rate of around 7000 MDCT examinations. All of them were carried out using a single 64row MDCT system. The hospital logbook was used to identify the number of CT examinations and dose levels associated with some typical diagnostic procedures in order to make an analysis. The information was taken form the PACS and Dose Watch software and was analyzed. The article draws some measures towards improving the organization and reducing the dose, keeping the quality of the performed exams. Thanks to the supportive software for dose tracking, analyzing and reporting, some problems have been solved and some reasonable measures have been implemented into the daily practice. (authors) Key words: RADIATION DOSE. MDCT. DOSE REDUCTION. REFERRAL GUIDELINES.CTDI. DLP

  12. Inactivation of hypoxic cells by cisplatin and radiation at clinically relevant doses

    International Nuclear Information System (INIS)

    Korbelik, M.; Skov, K.A.

    1989-01-01

    We have examined the effects of exposure to cisplatin [cis-diamminedichloroplatinum(II)] on the response of exponentially growing V79 cells to low (0-4 Gy) and high (up to 30 Gy) doses of X rays under hypoxic and aerobic conditions. Survival in both dose regions was assessed by clonogenic assays; the low-dose studies were facilitated by a Cell Analyser. The results show that cisplatin, like its isomer trans-DDP, exhibits greater interaction with low than with high radiation doses in hypoxic cells. This increased interaction could be seen even with subtoxic exposures to cisplatin as low as 1 mumol dm-3. In contrast, with cells irradiated in air in the presence of either complex, the interaction seen with high doses of radiation is completely lost or greatly diminished in the low radiation dose region. Further experiments showed that enhanced interaction of hypoxic cells with low doses of radiation could be equally effective with cisplatin pretreatments in air or in hypoxia, even if the cells are exposed to cisplatin only after irradiation. In experiments with nonproliferating plateau-phase cultures, the same enhanced interaction was observed in the low-dose region. These results, for example enhancement ratios of 2.3 and 1.2 at low- and high-dose regions, respectively, for 5 mumol dm-3 cisplatin, are contrasted with those for nitroimidazoles which are better sensitizers in the high-dose region

  13. Phase I (or phase II) dose-ranging clinical trials: proposal of a two-stage Bayesian design.

    Science.gov (United States)

    Zohar, Sarah; Chevret, Sylvie

    2003-02-01

    We propose a new design for phase I (or phase II) dose-ranging clinical trials aiming at determining a dose of an experimental treatment to satisfy safety (respectively efficacy) requirements, at treating a sufficiently large number of patients to estimate the toxicity (respectively failure) probability of the dose level with a given reliability, and at stopping the trial early if it is likely that no dose is safe (respectively efficacious). A two-stage design was derived from the Continual Reassessment Method (CRM), with implementation of Bayesian criteria to generate stopping rules. A simulation study was conducted to compare the operating characteristics of the proposed two-stage design to those reached by the traditional CRM. Finally, two applications to real data sets are provided.

  14. Influence of Age and Dose of African Swine Fever Virus Infections on Clinical Outcome and Blood Parameters in Pigs.

    Science.gov (United States)

    Post, Jacob; Weesendorp, Eefke; Montoya, Maria; Loeffen, Willie L

    African swine fever (ASF) is a fatal disease for domestic pigs, leading to serious economic losses in countries where ASF is endemic. Despite extensive research, efficient vaccines against ASF are lacking. Since peripheral blood cells are important mediators for vaccines, we study the impact of ASF on blood parameters in pigs with different ages and infected with different doses of ASF virus. Four different groups were studied: (1) 12 weeks of age/low virus dose; (2) 12 weeks of age/high virus dose; (3) 18 weeks of age/low virus dose; and (4) 18 weeks of age/high virus dose. By varying in age and/or ASFV inoculation dose, we monitor blood parameters during different degrees of disease. Thirty percent of the pigs survived the infection with a moderately virulent strain of African swine fever virus (ASFV). Animals that did survive infection were generally older, independent from the inoculation dose used. A firm reduction in many different cell types at 3-5 days postinfection (DPI) was accompanied by an increase in body temperature, followed by clinical signs and mortality from day 6 PI. While blood parameters generally normalized in survivors, γδ T cells and IL-10 levels could be related to mortality. These conclusions should be considered in new approaches for protection against ASF.

  15. Determination of air kerma standard of high dose rate {sup 192}Ir brachytherapy source; Determinacao da taxa de kerma no ar de referencia para {sup 192}Ir de alta taxa de dose para braquiterapia

    Energy Technology Data Exchange (ETDEWEB)

    Pires, E.J.; Alves, C.F.E.; Leite, S.P.; Magalhaes, L.A.G.; David, M.G.; Almeida, C.E. de, E-mail: cfealves@gmail.com [Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, RJ (Brazil). Lab. de Ciencias Radiologicas; Di Prinzio, R. [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2015-07-01

    This paper presents the methodology developed by the Laboratorio de Ciencias Radiologicas and presently in use for determining of the air kerma standard of {sup 192}Ir high dose rate sources to calibrate well-type chambers. Uncertainty analysis involving the measurements procedure are presented. (author)

  16. A standardized SOA for clinical data interchange in a cardiac telemonitoring environment.

    Science.gov (United States)

    Gazzarata, Roberta; Vergari, Fabio; Cinotti, Tullio Salmon; Giacomini, Mauro

    2014-11-01

    Care of chronic cardiac patients requires information interchange between patients' homes, clinical environments, and the electronic health record. Standards are emerging to support clinical information collection, exchange and management and to overcome information fragmentation and actors delocalization. Heterogeneity of information sources at patients' homes calls for open solutions to collect and accommodate multidomain information, including environmental data. Based on the experience gained in a European Research Program, this paper presents an integrated and open approach for clinical data interchange in cardiac telemonitoring applications. This interchange is supported by the use of standards following the indications provided by the national authorities of the countries involved. Taking into account the requirements provided by the medical staff involved in the project, the authors designed and implemented a prototypal middleware, based on a service-oriented architecture approach, to give a structured and robust tool to congestive heart failure patients for their personalized telemonitoring. The middleware is represented by a health record management service, whose interface is compliant to the healthcare services specification project Retrieve, Locate and Update Service standard (Level 0), which allows communication between the agents involved through the exchange of Clinical Document Architecture Release 2 documents. Three performance tests were carried out and showed that the prototype completely fulfilled all requirements indicated by the medical staff; however, certain aspects, such as authentication, security and scalability, should be deeply analyzed within a future engineering phase.

  17. Single versus repeat doses of misoprostol for treatment of early pregnancy loss-a randomized clinical trial.

    Science.gov (United States)

    Mizrachi, Yossi; Dekalo, Ann; Gluck, Ohad; Miremberg, Hadas; Dafna, Lotem; Feldstein, Ohad; Weiner, Eran; Bar, Jacob; Sagiv, Ron

    2017-06-01

    Does repeat administration of misoprostol for early pregnancy loss increase the treatment success rate? Repeat administration of misoprostol does not increase the treatment success rate, and is associated with more analgesics use. Misoprostol reduces the need for surgical evacuation and shortens the time to complete expulsion in patients with early pregnancy loss. However, the impact of repeat doses of misoprostol is not clear. A randomized clinical trial was conducted in a single tertiary hospital, recruiting women with early pregnancy loss (misoprostol vaginally on Day 1, and were then randomly assigned into two groups: Patients in the single-dose group were evaluated on Day 8. Patients in the repeat-dose group were evaluated on Day 4, when they were given a repeat dose if required, and scheduled for re-evaluation on Day 8. If complete expulsion was not achieved on Day 8 (endometrial thickness >15 mm or the presence of gestational sac on transvaginal sonography), participants underwent surgical evacuation. The primary outcome was treatment success, defined as no need for surgical intervention up to Day 8. Final analysis included 87 participants in the single-dose group and 84 participants in the repeat-dose group, out of whom 41 (48.8%) received a second dose. Treatment succeeded in 67 (77%) patients in the single-dose group and 64 (76%) patients in the repeat-dose group (RR 0.98; 95% CI 0.83-1.16; P = 0.89). Patients in the repeat-dose group reported more use of over the counter analgesics (82.1% versus 69.0%, P = 0.04). The study was not blinded and our definition of complete expulsion may be debated. Follow-up time was not equal in all participants, since some had a complete expulsion on Day 4 and some underwent emergent D&C before Day 8. This, however, should not affect the primary outcome. Our results suggest that a single-dose protocol is superior to a repeat-dose protocol due to a comparable success rate and more favorable outcomes regarding the need for

  18. Standard requirements for GCP-compliant data management in multinational clinical trials

    LENUS (Irish Health Repository)

    Ohmann, Christian

    2011-03-22

    Abstract Background A recent survey has shown that data management in clinical trials performed by academic trial units still faces many difficulties (e.g. heterogeneity of software products, deficits in quality management, limited human and financial resources and the complexity of running a local computer centre). Unfortunately, no specific, practical and open standard for both GCP-compliant data management and the underlying IT-infrastructure is available to improve the situation. For that reason the "Working Group on Data Centres" of the European Clinical Research Infrastructures Network (ECRIN) has developed a standard specifying the requirements for high quality GCP-compliant data management in multinational clinical trials. Methods International, European and national regulations and guidelines relevant to GCP, data security and IT infrastructures, as well as ECRIN documents produced previously, were evaluated to provide a starting point for the development of standard requirements. The requirements were produced by expert consensus of the ECRIN Working group on Data Centres, using a structured and standardised process. The requirements were divided into two main parts: an IT part covering standards for the underlying IT infrastructure and computer systems in general, and a Data Management (DM) part covering requirements for data management applications in clinical trials. Results The standard developed includes 115 IT requirements, split into 15 separate sections, 107 DM requirements (in 12 sections) and 13 other requirements (2 sections). Sections IT01 to IT05 deal with the basic IT infrastructure while IT06 and IT07 cover validation and local software development. IT08 to IT015 concern the aspects of IT systems that directly support clinical trial management. Sections DM01 to DM03 cover the implementation of a specific clinical data management application, i.e. for a specific trial, whilst DM04 to DM12 address the data management of trials across the unit

  19. Estimation and comparison of effective dose (E) in standard chest CT by organ dose measurements and dose-length-product methods and assessment of the influence of CT tube potential (energy dependency) on effective dose in a dual-source CT.

    Science.gov (United States)

    Paul, Jijo; Banckwitz, Rosemarie; Krauss, Bernhard; Vogl, Thomas J; Maentele, Werner; Bauer, Ralf W

    2012-04-01

    To determine effective dose (E) during standard chest CT using an organ dose-based and a dose-length-product-based (DLP) approach for four different scan protocols including high-pitch and dual-energy in a dual-source CT scanner of the second generation. Organ doses were measured with thermo luminescence dosimeters (TLD) in an anthropomorphic male adult phantom. Further, DLP-based dose estimates were performed by using the standard 0.014mSv/mGycm conversion coefficient k. Examinations were performed on a dual-source CT system (Somatom Definition Flash, Siemens). Four scan protocols were investigated: (1) single-source 120kV, (2) single-source 100kV, (3) high-pitch 120kV, and (4) dual-energy with 100/Sn140kV with equivalent CTDIvol and no automated tube current modulation. E was then determined following recommendations of ICRP publication 103 and 60 and specific k values were derived. DLP-based estimates differed by 4.5-16.56% and 5.2-15.8% relatively to ICRP 60 and 103, respectively. The derived k factors calculated from TLD measurements were 0.0148, 0.015, 0.0166, and 0.0148 for protocol 1, 2, 3 and 4, respectively. Effective dose estimations by ICRP 103 and 60 for single-energy and dual-energy protocols show a difference of less than 0.04mSv. Estimates of E based on DLP work equally well for single-energy, high-pitch and dual-energy CT examinations. The tube potential definitely affects effective dose in a substantial way. Effective dose estimations by ICRP 103 and 60 for both single-energy and dual-energy examinations differ not more than 0.04mSv. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  20. Depth dose distribution in the water for clinical applicators of 90Sr + 90Y, with a extrapolation mini chamber

    International Nuclear Information System (INIS)

    Antonio, Patricia de Lara; Caldas, Linda V.E.; Oliveira, Mercia L.

    2009-01-01

    This work determines the depth dose in the water for clinical applicators of 90 Sr + 90 Y, using a extrapolation mini chamber developed at the IPEN, Sao Paulo, Brazil, and different thickness acrylic plates. The obtained results were compared with the international recommendations and were considered satisfactory

  1. Experimental Platform for Ultra-high Dose Rate FLASH Irradiation of Small Animals Using a Clinical Linear Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Schüler, Emil; Trovati, Stefania; King, Gregory; Lartey, Frederick; Rafat, Marjan; Villegas, Manuel; Praxel, A. Joe [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California (United States); Loo, Billy W., E-mail: BWLoo@stanford.edu [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California (United States); Stanford Cancer Institute, Stanford University School of Medicine, Stanford, California (United States); Maxim, Peter G., E-mail: PMaxim@stanford.edu [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California (United States); Stanford Cancer Institute, Stanford University School of Medicine, Stanford, California (United States)

    2017-01-01

    Purpose: A key factor limiting the effectiveness of radiation therapy is normal tissue toxicity, and recent preclinical data have shown that ultra-high dose rate irradiation (>50 Gy/s, “FLASH”) potentially mitigates this effect. However, research in this field has been strongly limited by the availability of FLASH irradiators suitable for small animal experiments. We present a simple methodologic approach for FLASH electron small animal irradiation with a clinically available linear accelerator (LINAC). Methods and Materials: We investigated the FLASH irradiation potential of a Varian Clinac 21EX in both clinical mode and after tuning of the LINAC. We performed detailed FLUKA Monte Carlo and experimental dosimetric characterization at multiple experimental locations within the LINAC head. Results: Average dose rates of ≤74 Gy/s were achieved in clinical mode, and the dose rate after tuning exceeded 900 Gy/s. We obtained 220 Gy/s at 1-cm depth for a >4-cm field size with 90% homogeneity throughout a 2-cm-thick volume. Conclusions: We present an approach for using a clinical LINAC for FLASH irradiation. We obtained dose rates exceeding 200 Gy/s after simple tuning of the LINAC, with excellent dosimetric properties for small animal experiments. This will allow for increased availability of FLASH irradiation to the general research community.

  2. A systematic review of Bisphenol A "low dose" studies in the context of human exposure: a case for establishing standards for reporting "low-dose" effects of chemicals.

    Science.gov (United States)

    Teeguarden, Justin G; Hanson-Drury, Sesha

    2013-12-01

    Human exposure to the chemical Bisphenol A is almost ubiquitous in surveyed industrialized societies. Structural features similar to estrogen confer the ability of Bisphenol A (BPA) to bind estrogen receptors, giving BPA membership in the group of environmental pollutants called endocrine disruptors. References by scientists, the media, political entities, and non-governmental organizations to many toxicity studies as "low dose" has led to the belief that exposure levels in these studies are similar to humans, implying that BPA is toxic to humans at current exposures. Through systematic, objective comparison of our current, and a previous compilation of the "low-dose" literature to multiple estimates of human external and internal exposure levels, we found that the "low-dose" moniker describes exposures covering 8-12 orders of magnitude, the majority (91-99% of exposures) being greater than the upper bound of human exposure in the general infant, child and adult U.S. Population. "low dose" is therefore a descriptor without specific meaning regarding human exposure. Where human exposure data are available, for BPA and other environmental chemicals, reference to toxicity study exposures by direct comparison to human exposure would be more informative, more objective, and less susceptible to misunderstanding. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. The optimum bolus dose of remifentanil to facilitate laryngeal mask airway insertion with a single standard dose of propofol at induction in children.

    Science.gov (United States)

    Kwak, H J; Kim, J Y; Kim, Y B; Chae, Y J; Kim, J Y

    2008-09-01

    The purpose of this study was to determine the optimal bolus dose of remifentanil required for the successful insertion of the laryngeal mask airway during propofol induction in children without a neuromuscular blocking agent. Twenty-six paediatric patients, aged 3-10 years, requiring anaesthesia for short ambulatory surgery were recruited. A predetermined bolus dose of remifentanil was injected over 30 s, followed by propofol 2.5 mg.kg(-1) over 10 s. The bolus dose of remifentanil was determined by a modified Dixon's up-and-down method, starting from 0.5 microg.kg(-1) (0.1 microg.kg(-1) as a step size). Laryngeal mask insertion was attempted 90 s after the end of remifentanil injection and the response of patients was classified as either 'movement' or 'no movement'. The bolus dose of remifentanil at which there was a 50% probability of successful laryngeal mask insertion (ED(50)) during induction with 2.5 mg.kg(-1) propofol was 0.56 (0.07) microg.kg(-1) in children without a neuromuscular blocking agent. From probit analysis, the ED(50) and ED(95) of remifentanil were 0.52 microg.kg(-1) (95% confidence limits, 0.42-0.62 microg.kg(-1)) and 0.71 microg.kg(-1) (95% confidence limits, 0.61-1.40 microg.kg(-1)), respectively.

  4. SU-F-T-433: Evaluation of a New Dose Mimicking Application for Clinical Flexibility and Reliability

    Energy Technology Data Exchange (ETDEWEB)

    Hoffman, D; Nair, C Kumaran; Wright, C; Yamamoto, T; Mayadev, J; Valicenti, R; Benedict, S; Rong, Y [University of California Davis Medical Center, Sacramento, CA (United States); Markham, J [Raysearch Laboratories, Garden City, NY (United States)

    2016-06-15

    Purpose: Clinical workflow and machine down time occasionally require patients to be temporarily treated on a system other than the initial treatment machine. A new commercial dose mimicking application provides automated cross-platform treatment planning to expedite this clinical flexibility. The aim of this work is to evaluate the feasibility of automatic plan creation and establish a robust clinical workflow for prostate and pelvis patients. Methods: Five prostate and five pelvis patients treated with helical plans were selected for re-planning with the dose mimicking application, covering both simple and complex scenarios. Two-arc VMAT and 7- and 9-field IMRT plans were generated for each case, with the objective function of achieving similar dose volume histogram from the initial helical plans. Dosimetric comparisons include target volumes and organs at risk (OARs) (rectum, bladder, small bowel, femoral heads, etc.). Dose mimicked plans were evaluated by a radiation oncologist, and patient-specific QAs were performed to validate delivery. Results: Overall plan generation and transfer required around 30 minutes of dosimetrist’s time once the dose-mimicking protocol is setup for each site. The resulting VMAT and 7- and 9-field IMRT plans achieved equivalent PTV coverage and homogeneity (D99/DRx = 97.3%, 97.2%, 97.2% and HI = 6.0, 5.8, and 5.9, respectively), compared to helical plans (97.6% and 4.6). The OAR dose discrepancies were up to 6% in rectum Dmean, but generally lower in bladder, femoral heads, bowel and penile bulb. In the context of 1–5 fractions, the radiation oncologist evaluated the dosimetric changes as not clinically significant. All delivery QAs achieved >90% pass with a 3%/3mm gamma criteria. Conclusion: The automated dose-mimicking workflow offers a strategy to avoid missing treatment fractions due to machine down time with non-clinically significant changes in dosimetry. Future work will further optimize dose mimicking plans and

  5. Open-Label Comparative Clinical Study of Chlorproguanil−Dapsone Fixed Dose Combination (Lapdap™) Alone or with Three Different Doses of Artesunate for Uncomplicated Plasmodium falciparum Malaria

    Science.gov (United States)

    Wootton, Daniel G.; Opara, Hyginus; Biagini, Giancarlo A.; Kanjala, Maxwell K.; Duparc, Stephan; Kirby, Paula L.; Woessner, Mary; Neate, Colin; Nyirenda, Maggie; Blencowe, Hannah; Dube-Mbeye, Queen; Kanyok, Thomas; Ward, Stephen; Molyneux, Malcolm; Dunyo, Sam; Winstanley, Peter A.

    2008-01-01

    The objective of this study was to determine the appropriate dose of artesunate for use in a fixed dose combination therapy with chlorproguanil−dapsone (CPG−DDS) for the treatment of uncomplicated falciparum malaria. Methods Open-label clinical trial comparing CPG−DDS alone or with artesunate 4, 2, or 1 mg/kg at medical centers in Blantyre, Malawi and Farafenni, The Gambia. The trial was conducted between June 2002 and February 2005, including 116 adults (median age 27 years) and 107 children (median age 38 months) with acute uncomplicated Plasmodium falciparum malaria. Subjects were randomized into 4 groups to receive CPG–DDS alone or plus 4, 2 or 1 mg/kg of artesunate once daily for 3 days. Assessments took place on Days 0−3 in hospital and follow-up on Days 7 and 14 as out-patients. Efficacy was evaluated in the Day 3 per-protocol (PP) population using mean time to reduce baseline parasitemia by 90% (PC90). A number of secondary outcomes were also included. Appropriate artesunate dose was determined using a pre-defined decision matrix based on primary and secondary outcomes. Treatment emergent adverse events were recorded from clinical assessments and blood parameters. Safety was evaluated in the intent to treat (ITT) population. Results In the Day 3 PP population for the adult group (N = 85), mean time to PC90 was 19.1 h in the CPG−DDS group, significantly longer than for the +artesunate 1 mg/kg (12.5 h; treatment difference −6.6 h [95%CI −11.8, −1.5]), 2 mg/kg (10.7 h; −8.4 h [95%CI −13.6, −3.2]) and 4 mg/kg (10.3 h; −8.7 h [95%CI −14.1, −3.2]) groups. For children in the Day 3 PP population (N = 92), mean time to PC90 was 21.1 h in the CPG−DDS group, similar to the +artesunate 1 mg/kg group (17.7 h; −3.3 h [95%CI −8.6, 2.0]), though the +artesunate 2 mg/kg and 4 mg/kg groups had significantly shorter mean times to PC90 versus CPG−DDS; 14.4 h (treatment difference −6.4 h [95%CI −11.7, −1.0]) and 12.8 h (−7

  6. Open-label comparative clinical study of chlorproguanil-dapsone fixed dose combination (Lapdap alone or with three different doses of artesunate for uncomplicated Plasmodium falciparum malaria.

    Directory of Open Access Journals (Sweden)

    Daniel G Wootton

    2008-03-01

    Full Text Available The objective of this study was to determine the appropriate dose of artesunate for use in a fixed dose combination therapy with chlorproguanil-dapsone (CPG-DDS for the treatment of uncomplicated falciparum malaria.Open-label clinical trial comparing CPG-DDS alone or with artesunate 4, 2, or 1 mg/kg at medical centers in Blantyre, Malawi and Farafenni, The Gambia. The trial was conducted between June 2002 and February 2005, including 116 adults (median age 27 years and 107 children (median age 38 months with acute uncomplicated Plasmodium falciparum malaria. Subjects were randomized into 4 groups to receive CPG-DDS alone or plus 4, 2 or 1 mg/kg of artesunate once daily for 3 days. Assessments took place on Days 0-3 in hospital and follow-up on Days 7 and 14 as out-patients. Efficacy was evaluated in the Day 3 per-protocol (PP population using mean time to reduce baseline parasitemia by 90% (PC90. A number of secondary outcomes were also included. Appropriate artesunate dose was determined using a pre-defined decision matrix based on primary and secondary outcomes. Treatment emergent adverse events were recorded from clinical assessments and blood parameters. Safety was evaluated in the intent to treat (ITT population.In the Day 3 PP population for the adult group (N = 85, mean time to PC90 was 19.1 h in the CPG-DDS group, significantly longer than for the +artesunate 1 mg/kg (12.5 h; treatment difference -6.6 h [95%CI -11.8, -1.5], 2 mg/kg (10.7 h; -8.4 h [95%CI -13.6, -3.2] and 4 mg/kg (10.3 h; -8.7 h [95%CI -14.1, -3.2] groups. For children in the Day 3 PP population (N = 92, mean time to PC90 was 21.1 h in the CPG-DDS group, similar to the +artesunate 1 mg/kg group (17.7 h; -3.3 h [95%CI -8.6, 2.0], though the +artesunate 2 mg/kg and 4 mg/kg groups had significantly shorter mean times to PC90 versus CPG-DDS; 14.4 h (treatment difference -6.4 h [95%CI -11.7, -1.0] and 12.8 h (-7.4 h [95%CI -12.9, -1.8], respectively. An analysis of mean time

  7. [Standardized management of acupuncture-moxibustion clinic in Singapore General Hospital].

    Science.gov (United States)

    Cui, Shu-Li; Tan, Kian Hian; Ong, Biauw Chi; Lim, Shih hui; Yong, Yang; Seah, Cheng Ngee; Huang, Youyi; Han, Seong Ng

    2014-02-01

    The standardized management of acupuncture-moxibustion in Singapore General Hospital is introduced. With gradual improvement of outpatient infrastructure, re-training of medical staff, strict disinfection of manipulation, periodical inspection of medical instruments, unified management of writing, saving and processing in medical records and public education of TCM knowledge, a standardized management system in accordance with modernized hospital is gradually established. As a result, efficiency and quality of clinical treatment is continuously increasing. From April of 1998 to December of 2012, a total of 74 654 times of treatment were performed, and treatment amount per day is gradually increased. The unusual condition of acupuncture is avoided. Periodical strict inspection of joint committee authenticated by domestic and overseas medical health organization is repeatedly passed and accepted. Additionally, three clinical researches funded by Singapore Health-care Company are still in progress in acupuncture-moxibustion department.

  8. [Effect of standardized PICC training and management on the clinical effect and complication of catheterization].

    Science.gov (United States)

    Zhang, Jinghui; Tang, Siyuan; He, Lianxiang; Chen, Wenfeng; Jiang, Pinglan; Hu, Yuanping; Chen, Hua

    2014-06-01

    To determine the clinical effect of standardized training and management of peripherally inserted central catheter (PICC) and catheter-related complications. A total of 610 patients were divided into a control group and an observation group, the control group (n=300) were catheterized by trainees who received "short-term intensive training", the observation group (n=310) by "system standardized training and management". The clinical efficacy of catheterization and the rate of catheter-related complications were compared. There was significant difference in the one-time puncture success rate, one-time cannulation success rate, the time for operation and the pain score between the 2 groups (all PPICC training and management can improve the effect of catheterization and reduce the incidence of PICC-related complication.

  9. Dose distribution of gamma radiation in a new geometric configuration of a standard carton date package and its experimental application for disinfestation of packed dates

    Science.gov (United States)

    Ahmed, M. S. H.; Al-Taweel, A. A.; Hameed, A. A.

    1994-06-01

    A new geometrical configuration composed of three standard carton boxes (SCBs) full with polyethylene bags (PBs), where each bag contains 1 kg of date, was placed on a single turntable of Gammabeam-650 and irradiated with low doses. The mean "radiation absorbed dose" for disinfestation of this geometrical unit at 15 equally distributed positions (Fricke dosimeters) inside 3 SCBs put on a single turntable was calculated to be 0.46 ± 0.20 kGy and dose uniformity ratio ( U) = 1.0019/0.2500 = 4.00. The development and genetic tests carried out on insects found in the PBs 1-2 days after irradiation resulted in that all insects were completely sterile and died within a short period of time. No sign of any reinfestation was recorded at all in the treated packages even after 30 days of storage in an insectory. Apparently the prevention of insects from invading and/or penetrating the date packages is due mainly to the new combination of standard carton boxes that are widely used for commercial purposes and hermetically heat-sealed polyethylene bags of dates in addition to the entire prevention of reproduction induced by the "low" doses of γ radiation. Therefore, by using similar geometrical configuration, 18 big standard carton date packages can be simultaneously disinfected, using the same range of doses or so, by utilizing all the 6 turntables inside the radiation chamber of the Gammabeam-650 irradiation facility.

  10. Clinical trial or standard treatment? Shared decision making at the department of oncology

    DEFF Research Database (Denmark)

    Gregersen, Trine Ammentorp; Birkelund, Regner; Ammentorp, Jette

    2016-01-01

    Title: Clinical trial or standard treatment? Shared decision making at the department of oncology. Authors: Ph.d. student, Trine A. Gregersen. Trine.gregersen@rsyd.dk. Department of Oncology. Health Services Research Unit Lillebaelt Hospital / IRS University of Southern Denmark. Professor, Regner...... Analyzing field notes: • How to write useful field notes? • How to analyze field notes systematically? • Using Nvivo when analyzing field notes and interviews?...

  11. Randomized dose-finding clinical trial of oncolytic immunotherapeutic vaccinia JX-594 in liver cancer

    Science.gov (United States)

    Heo, Jeong; Reid, Tony; Ruo, Leyo; Breitbach, Caroline J; Rose, Steven; Bloomston, Mark; Cho, Mong; Lim, Ho Yeong; Chung, Hyun Cheol; Kim, Chang Won; Burke, James; Lencioni, Riccardo; Hickman, Theresa; Moon, Anne; Lee, Yeon Sook; Kim, Mi Kyeong; Daneshmand, Manijeh; Dubois, Kara; Longpre, Lara; Ngo, Minhtran; Rooney, Cliona; Bell, John C; Rhee, Byung-Geon; Patt, Richard; Hwang, Tae-Ho; Kirn, David H

    2014-01-01

    Oncolytic viruses and active immunotherapeutics have complementary mechanisms of action (MOA) that are both self amplifying in tumors, yet the impact of dose on subject outcome is unclear. JX-594 (Pexa-Vec) is an oncolytic and immunotherapeutic vaccinia virus. To determine the optimal JX-594 dose in subjects with advanced hepatocellular carcinoma (HCC), we conducted a randomized phase 2 dose-finding trial (n = 30). Radiologists infused low-or high-dose JX-594 into liver tumors (days 1, 15 and 29); infusions resulted in acute detectable intravascular JX-594 genomes. Objective intrahepatic Modified Response Evaluation Criteria in Solid Tumors (mRECIST) (15%) and Choi (62%) response rates and intrahepatic disease control (50%) were equivalent in injected and distant noninjected tumors at both doses. JX-594 replication and granulocyte-macrophage colony-stimulating factor (GM-CSF) expression preceded the induction of anticancer immunity. In contrast to tumor response rate and immune endpoints, subject survival duration was significantly related to dose (median survival of 14.1 months compared to 6.7 months on the high and low dose, respectively; hazard ratio 0.39; P = 0.020). JX-594 demonstrated oncolytic and immunotherapy MOA, tumor responses and dose-related survival in individuals with HCC. PMID:23396206

  12. Ultra-low dose abdominal MDCT: Using a knowledge-based Iterative Model Reconstruction technique for substantial dose reduction in a prospective clinical study

    Energy Technology Data Exchange (ETDEWEB)

    Khawaja, Ranish Deedar Ali, E-mail: rkhawaja@mgh.harvard.edu [MGH Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Singh, Sarabjeet; Blake, Michael; Harisinghani, Mukesh; Choy, Gary; Karosmangulu, Ali; Padole, Atul; Do, Synho [MGH Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Brown, Kevin; Thompson, Richard; Morton, Thomas; Raihani, Nilgoun [CT Research and Advanced Development, Philips Healthcare, Cleveland, OH (United States); Koehler, Thomas [Philips Technologie GmbH, Innovative Technologies, Hamburg (Germany); Kalra, Mannudeep K. [MGH Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States)

    2015-01-15

    Highlights: • Limited abdominal CT indications can be performed at a size specific dose estimate of (SSDE) 1.5 mGy (∼0.9 mSv) in smaller patients (BMI less than or equal to 25 kg/m{sup 2}) using a knowledge based Iterative Model Reconstruction (IMR) technique. • Evaluation of liver tumors and pathologies is unacceptable at this reduced dose with IMR technique especially in patients with a BMI greater than 25 kg/m{sup 2}. • IMR body soft tissue and routine settings perform substantially better than IMR sharp plus setting in reduced dose CT images. • At SSDE of 1.5 mGy, objective image noise in reduced dose IMR images is 8–56% less than compared to standard dose FBP images, with lowest image noise in IMR body-soft tissue images. - Abstract: Purpose: To assess lesion detection and image quality parameters of a knowledge-based Iterative Model Reconstruction (IMR) in reduced dose (RD) abdominal CT examinations. Materials and methods: This IRB-approved prospective study included 82 abdominal CT examinations performed for 41 consecutive patients (mean age, 62 ± 12 years; F:M 28:13) who underwent a RD CT (SSDE, 1.5 mGy ± 0.4 [∼0.9 mSv] at 120 kV with 17–20 mAs/slice) immediately after their standard dose (SD) CT exam (10 mGy ± 3 [∼6 mSv] at 120 kV with automatic exposure control) on 256 MDCT (iCT, Philips Healthcare). SD data were reconstructed using filtered back projection (FBP). RD data were reconstructed with FBP and IMR. Four radiologists used a five-point scale (1 = image quality better than SD CT to 5 = image quality unacceptable) to assess both subjective image quality and artifacts. Lesions were first detected on RD FBP images. RD IMR and RD FBP images were then compared side-by-side to SD-FBP images in an independent, randomized and blinded fashion. Friedman's test and intraclass correlation coefficient were used for data analysis. Objective measurements included image noise and attenuation as well as noise spectral density (NSD) curves

  13. Ultra-low dose abdominal MDCT: Using a knowledge-based Iterative Model Reconstruction technique for substantial dose reduction in a prospective clinical study

    International Nuclear Information System (INIS)

    Khawaja, Ranish Deedar Ali; Singh, Sarabjeet; Blake, Michael; Harisinghani, Mukesh; Choy, Gary; Karosmangulu, Ali; Padole, Atul; Do, Synho; Brown, Kevin; Thompson, Richard; Morton, Thomas; Raihani, Nilgoun; Koehler, Thomas; Kalra, Mannudeep K.

    2015-01-01

    Highlights: • Limited abdominal CT indications can be performed at a size specific dose estimate of (SSDE) 1.5 mGy (∼0.9 mSv) in smaller patients (BMI less than or equal to 25 kg/m 2 ) using a knowledge based Iterative Model Reconstruction (IMR) technique. • Evaluation of liver tumors and pathologies is unacceptable at this reduced dose with IMR technique especially in patients with a BMI greater than 25 kg/m 2 . • IMR body soft tissue and routine settings perform substantially better than IMR sharp plus setting in reduced dose CT images. • At SSDE of 1.5 mGy, objective image noise in reduced dose IMR images is 8–56% less than compared to standard dose FBP images, with lowest image noise in IMR body-soft tissue images. - Abstract: Purpose: To assess lesion detection and image quality parameters of a knowledge-based Iterative Model Reconstruction (IMR) in reduced dose (RD) abdominal CT examinations. Materials and methods: This IRB-approved prospective study included 82 abdominal CT examinations performed for 41 consecutive patients (mean age, 62 ± 12 years; F:M 28:13) who underwent a RD CT (SSDE, 1.5 mGy ± 0.4 [∼0.9 mSv] at 120 kV with 17–20 mAs/slice) immediately after their standard dose (SD) CT exam (10 mGy ± 3 [∼6 mSv] at 120 kV with automatic exposure control) on 256 MDCT (iCT, Philips Healthcare). SD data were reconstructed using filtered back projection (FBP). RD data were reconstructed with FBP and IMR. Four radiologists used a five-point scale (1 = image quality better than SD CT to 5 = image quality unacceptable) to assess both subjective image quality and artifacts. Lesions were first detected on RD FBP images. RD IMR and RD FBP images were then compared side-by-side to SD-FBP images in an independent, randomized and blinded fashion. Friedman's test and intraclass correlation coefficient were used for data analysis. Objective measurements included image noise and attenuation as well as noise spectral density (NSD) curves to

  14. Standardization of Data for Clinical Use and Research in Spinal Cord Injury

    DEFF Research Database (Denmark)

    Biering-Sørensen, Fin; Noonan, Vanessa K

    2016-01-01

    for use in SCI clinical practice and research. Reporting of SCI data is likewise standardized. Data elements are continuously updated and developed using an open and transparent process. There are ongoing internal, as well as external review processes, where all interested parties are encouraged...... to participate. The purpose of this review paper is to provide an overview of the initiatives to standardize data including the International Spinal Cord Society's International SCI Data Sets and the National Institutes of Health, National Institute of Neurological Disorders and Stroke Common Data Elements......Increased survival after spinal cord injury (SCI) worldwide has enhanced the need for quality data that can be compared and shared between centers, countries, as well as across research studies, to better understand how best to prevent and treat SCI. Such data should be standardized and be able...

  15. Clinically relevant doses of lidocaine and bupivacaine do not impair cutaneous wound healing in mice.

    Science.gov (United States)

    Waite, A; Gilliver, S C; Masterson, G R; Hardman, M J; Ashcroft, G S

    2010-06-01

    Lidocaine and bupivacaine are commonly infiltrated into surgical cutaneous wounds to provide local anaesthesia after surgical procedures. However, very little is known about their effects on cutaneous wound healing. If an inhibitory effect is demonstrated, then the balance between the benefits of postoperative local anaesthesia and the negatives of impaired cutaneous wound healing may affect the decision to use local anaesthesia or not. Furthermore, if a difference in the rate of healing of lidocaine- and bupivacaine-treated cutaneous wounds is revealed, or if an inhibitory effect is found to be dose-dependent, then this may well influence the choice of agent and its concentration for clinical use. Immediately before incisional wounding, we administered lidocaine and bupivacaine intradermally to adult female mice, some of which had been ovariectomized to act as a model of post-menopausal women (like post-menopausal women, ovariectomized mice heal wounds poorly, with increased proteolysis and inflammation). Day 3 wound tissue was analysed histologically and tested for expression of inflammatory and proteolytic factors. On day 3 post-wounding, wound areas and extent of re-epithelialization were comparable between the control and local anaesthetic-treated animals, in both intact and ovariectomized groups. Both tested drugs significantly increased wound activity of the degradative enzyme matrix metalloproteinase-2 relative to controls, while lidocaine also increased wound neutrophil numbers. Although lidocaine and bupivacaine influenced local inflammatory and proteolytic factors, they did not impair the rate of healing in either of two well-established models (mimicking normal human wound healing and impaired age-related healing).

  16. Dose-response effects of medical exercise therapy in patients with patellofemoral pain syndrome: a randomised controlled clinical trial.

    Science.gov (United States)

    Østerås, Berit; Østerås, Håvard; Torstensen, Tom Arild; Vasseljen, Ottar

    2013-06-01

    To evaluate two different therapeutic exercise regimens in patients with patellofemoral pain syndrome (PFPS). Multicentre, randomised controlled clinical trial. Three primary healthcare physiotherapy clinics. Forty-two patients with PFPS were assigned at random to an experimental group or a control group. Forty participants completed the study. Both groups received three treatments per week for 12 weeks. The experimental group received high-dose, high-repetition medical exercise therapy, and the control group received low-dose, low-repetition exercise therapy. The groups differed in terms of number of exercises, number of repetitions and sets, and time spent performing aerobic/global exercises. Outcome parameters were pain (measured using a visual analogue scale) and function [measured using the step-down test and the modified Functional Index Questionnaire (FIQ)]. At baseline, there were no differences between the groups. After the interventions, there were statistically significant (Pexercise therapy has a dose-response effect on pain and functional outcomes in patients with PFPS. This indicates that high-dose, high-repetition medical exercise therapy is more efficacious than low-dose, low-repetition exercise therapy for this patient group. Copyright © 2012 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

  17. Low-dose growth hormone supplementation increases clinical pregnancy rate in poor responders undergoing in vitro fertilisation.

    Science.gov (United States)

    Lattes, Karinna; Brassesco, Mario; Gomez, Manuel; Checa, Miguel A

    2015-07-01

    Poor ovarian response (POR) often means low success rates after in vitro fertilisation (IVF). We aim to study the impact of a low-dose growth hormone (GH) supplementation in pregnancy rates in poor responders in a prospective, self-controlled study of 64 poor responders to previous IVF cycles, who failed to achieve pregnancy and were supplemented with low-doses of GH in a subsequent cycle using the same gonadotropin dose and protocol. Our primary endpoint was the clinical pregnancy rate (CPR), considering secondary endpoints, the number of retrieved oocytes, embryos, embryo quality and the proportion of cycles with embryo transfer. CPR in the GH group was 34.4%. Significant differences were observed for the GH group both in the number of top quality embryos (0.64 ± 0.88 versus 1.03 ± 1.17, p < 0.05) and cryopreserved embryos (0.3 ± 0.81 versus 0.85 ± 1.49, p < 0.05). This is, to our knowledge, the first clinical trial to use a low dose of GH as a supplement for IVF in POR patients. Despite this low dose, we achieved excellent success rates in patients with a very poor prognosis, at a reasonable cost and without side effects, which makes this a safe and cost-effective alternative.

  18. The effects of clinically relevant doses of amphetamine and methylphenidate on signal detection and DRL in rats

    Science.gov (United States)

    Andrzejewski, Matthew E.; Spencer, Robert C.; Harris, Rachel L.; Feit, Elizabeth C.; McKee, Brenda L.; Berridge, Craig W.

    2014-01-01

    Low dose amphetamine (AMPH) and methylphenidate (MPH, Ritalin®) are the most widely prescribed and most effective pharmacotherapy for attention-deficit/hyperactivity disorder (ADHD). Certain low, clinically relevant doses of MPH improve sustained attention and working memory in normal rats, in contrast to higher doses that impair cognitive ability and induce locomotor activity. However, the effects of AMPH of MPH on sustained attention and behavioral inhibition remain poorly characterized. The present experiments examined the actions of AMPH (0.1 and 0.25 mg/kg) and MPH (0.5 and 1.0 mg/kg) in a rat model of 1) sustained attention, where signal and blank trials were interspersed randomly and occurred at unpredictable times, and 2) behavioral inhibition, using a differential reinforcement of low rate (DRL) schedule. In a signal detection paradigm, both 0.5 mg/kg and 1.0 mg/kg MPH and 0.25 mg/kg AMPH improve sustained attention, however neither AMPH nor MPH improve behavioral inhibition on DRL. Taken together with other recent studies, it appears that clinically-relevant doses of AMPH and MPH may preferentially improve attention-related behavior while having little effect on behavioral inhibition. These observations provide additional insight into the basic behavioral actions of low-dose psychostimulants and further suggest that the use of sustained attention tasks may be important in the development of novel pharmacological treatments for ADHD. PMID:24467844

  19. Innovating cystic fibrosis clinical trial designs in an era of successful standard of care therapies.

    Science.gov (United States)

    VanDevanter, Donald R; Mayer-Hamblett, Nicole

    2017-11-01

    Evolving cystic fibrosis 'standards of care' have influenced recent cystic fibrosis clinical trial designs for new therapies; care additions/improvements will require innovative trial designs to maximize feasibility and efficacy detection. Three cystic fibrosis therapeutic areas (pulmonary exacerbations, Pseudomonas aeruginosa airway infections, and reduced cystic fibrosis transmembrane conductance regulator [CFTR] protein function) differ with respect to the duration for which recognized 'standards of care' have been available. However, developers of new therapies in all the three areas are affected by similar challenges: standards of care have become so strongly entrenched that traditional placebo-controlled studies in cystic fibrosis populations likely to benefit from newer therapies have become less and less feasible. Today, patients/clinicians are more likely to entertain participation in active-comparator trial designs, that have substantial challenges of their own. Foremost among these are the selection of 'valid' active comparator(s), estimation of a comparator's current clinical efficacy (required for testing noninferiority hypotheses), and effective blinding of commercially available comparators. Recent and future cystic fibrosis clinical trial designs will have to creatively address this collateral result of successful past development of effective cystic fibrosis therapies: patients and clinicians are much less likely to accept simple, placebo-controlled studies to evaluate future therapies.

  20. Fatigue and Relating Factors in High-Risk Breast Cancer Patients Treated With Adjuvant Standard or High-Dose Chemotherapy: A Longitudinal Study

    NARCIS (Netherlands)

    Nieboer, P.; Buijs, C.; Rodenhuis, S.; Seynaeve, C.; Beex, L.V.A.M.; Wall, E. van der; Richel, D.J.; Nooij, M.A.; Voest, E.E.; Hupperets, P.; Mulder, N.H.; Graaf, W.T.A. van der; TenVergert, E.M.; Tinteren, H. van; Vries, E.G.E. de

    2005-01-01

    PURPOSE Determine whether standard or high-dose chemotherapy leads to changes in fatigue, hemoglobin (Hb), mental health, muscle and joint pain, and menopausal status from pre- to posttreatment and to evaluate whether fatigue is associated with these factors in disease-free breast cancer patients.

  1. Fatigue and relating factors in high-risk breast cancer patients treated with adjuvant standard or high-dose chemotherapy: a longitudinal study.

    NARCIS (Netherlands)

    Nieboer, P.; Buijs, C.; Rodenhuis, S.; Seynaeve, C.; Beex, L.V.A.M.; Wall, E. van der; Richel, D.J.; Nooij, M.A.; Voest, E.E.; Hupperets, P.S.G.J.; Mulder, N.H.; Graaf, W.T.A. van der; Vergert, E.M. ten; Tinteren, H.L.G. van; Vries, E.G.F. de

    2005-01-01

    PURPOSE: Determine whether standard or high-dose chemotherapy leads to changes in fatigue, hemoglobin (Hb), mental health, muscle and joint pain, and menopausal status from pre- to post-treatment and to evaluate whether fatigue is associated with these factors in disease-free breast cancer patients.

  2. Fatigue and relating factors in high-risk breast cancer patients treated with adjuvant standard or high-dose chemotherapy: a longitudinal study

    NARCIS (Netherlands)

    Nieboer, Peter; Buijs, Ciska; Rodenhuis, Sjoerd; Seynaeve, Caroline; Beex, Louk V. A. M.; van der Wall, Elsken; Richel, Dick J.; Nooij, Marianne A.; Voest, Emile E.; Hupperets, Pierre; Mulder, Nanno H.; van der Graaf, Winette T. A.; TenVergert, Els M.; van Tinteren, Harm; de Vries, Elisabeth G. E.

    2005-01-01

    PURPOSE: Determine whether standard or high-dose chemotherapy leads to changes in fatigue, hemoglobin (Hb), mental health, muscle and joint pain, and menopausal status from pre- to post-treatment and to evaluate whether fatigue is associated with these factors in disease-free breast cancer patients.

  3. Fatigue and relating factors in high-risk breast cancer patients treated with adjuvant standard or high-dose chemotherapy : A longitudinal study

    NARCIS (Netherlands)

    Nieboer, P; Buijs, C; Rodenhuis, S; Seynaeve, C; Beex, LVAM; van der Wall, E; Richel, DJ; Nooij, MA; Voest, EE; Hupperets, P; Mulder, NH; van der Graaf, WTA; TenVergert, EM; van Tinteren, H; de Vries, EGE

    2005-01-01

    Purpose Determine whether standard or high-dose chemotherapy leads to changes in fatigue, hemoglobin (Hb), mental health, muscle and joint pain, and menopausal status from pre- to post-treatment and to evaluate whether fatigue is associated with these factors in disease-free breast cancer patients.

  4. Comparison BIPM.RI(I)-K8 of high dose-rate Ir-192 brachytherapy standards for reference air kerma rate of the VSL and the BIPM

    DEFF Research Database (Denmark)

    Alvarez, J.T.; De Pooter, J.A.; Andersen, Claus E.

    2014-01-01

    An indirect comparison of the standards for reference air kerma rate for 192Ir high dose rate brachytherapy sources of the Dutch Metrology Institute (VSL), The Netherlands, and of the Bureau International des Poids et Mesures (BIPM) was carried out at the VSL in November 2009. The comparison resu...

  5. Clinical efficacy of different doses of lipo-prostaglandin E1 in the treatment of painful diabetic peripheral neuropathy.

    Science.gov (United States)

    Hong, Lihua; Zhang, Jian; Shen, Jianguo

    2015-01-01

    To observe the clinical efficacy of different doses of alprostadil (lipo-prostaglandin E1, lipo-PGE1) in the treatment of painful diabetic peripheral neuropathy (DPN). Sixty patients with painful DPN were equally and randomly assigned into three groups. Two groups received different doses of lipo-PGE1 by intravenous drip injection (A group: low-dose lipo-PGE1; B group: high-dose lipo-PGE1) following intravenous bolus injection of mecobalamin (MeCbl, 0.5mg once daily (QD)); the third group received MeCbl alone (C group). All patients received optimized treatment to lower blood glucose, blood pressure, and blood lipids to target levels. The efficacy of lipo-PGE1 in the three groups of patients was observed after 3weeks of treatment. The overall response rate was 90% in the B group, significantly higher than that in the A and C groups (80% and 55%, respectively; P<0.05). During the observation period, there was no incidence of serious adverse reactions (e.g., acute heart failure, sudden drop in blood pressure, or malignant arrhythmias) in any of the three groups. High-dose lipo-PGE1 has better efficacy than low-dose lipo-PGE1 or MeCbl alone in the treatment of painful DPN. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. 2016 Updated American Society of Clinical Oncology/Oncology Nursing Society Chemotherapy Administration Safety Standards, Including Standards for Pediatric Oncology.

    Science.gov (United States)

    Neuss, Michael N; Gilmore, Terry R; Belderson, Kristin M; Billett, Amy L; Conti-Kalchik, Tara; Harvey, Brittany E; Hendricks, Carolyn; LeFebvre, Kristine B; Mangu, Pamela B; McNiff, Kristen; Olsen, MiKaela; Schulmeister, Lisa; Von Gehr, Ann; Polovich, Martha

    2016-12-01

    Purpose To update the ASCO/Oncology Nursing Society (ONS) Chemotherapy Administration Safety Standards and to highlight standards for pediatric oncology. Methods The ASCO/ONS Chemotherapy Administration Safety Standards were first published in 2009 and updated in 2011 to include inpatient settings. A subsequent 2013 revision expanded the standards to include the safe administration and management of oral chemotherapy. A joint ASCO/ONS workshop with stakeholder participation, including that of the Association of Pediatric Hematology Oncology Nurses and American Society of Pediatric Hematology/Oncology, was held on May 12, 2015, to review the 2013 standards. An extensive literature search was subsequently conducted, and public comments on the revised draft standards were solicited. Results The updated 2016 standards presented here include clarification and expansion of existing standards to include pediatric oncology and to introduce new standards: most notably, two-person verification of chemotherapy preparation processes, administration of vinca alkaloids via minibags in facilities in which intrathecal medications are administered, and labeling of medications dispensed from the health care setting to be taken by the patient at home. The standards were reordered and renumbered to align with the sequential processes of chemotherapy prescription, preparation, and administration. Several standards were separated into their respective components for clarity and to facilitate measurement of adherence to a standard. Conclusion As oncology practice has changed, so have chemotherapy administration safety standards. Advances in technology, cancer treatment, and education and training have prompted the need for periodic review and revision of the standards. Additional information is available at http://www.asco.org/chemo-standards .

  7. Correction of hyperbilirubinemia in gunn rats using clinically relevant low doses of helper-dependent adenoviral vectors.

    Science.gov (United States)

    Dimmock, David; Brunetti-Pierri, Nicola; Palmer, Donna J; Beaudet, Arthur L; Ng, Philip

    2011-04-01

    Crigler-Najjar syndrome type I is a severe inborn error of bilirubin metabolism caused by a complete deficiency of uridine diphospho-glucuronosyl transferase 1A1 (UGT1A1) and results in life-threatening unconjugated hyperbilirubinemia. Lifelong correction of hyperbilirubinemia by liver-directed gene therapy using a helper-dependent adenoviral (HDAd) vector has been previously reported in the Gunn rat, a model of Crigler-Najjar syndrome, but was only achieved using high doses (≥ 3 × 10(12) viral particles [vp]/kg), which are likely to elicit a severe toxic response in humans. Therefore, in this study, we investigate strategies to achieve correction of hyperbilirubinemia in the Gunn rat using clinically relevant low HDAd doses. We have found that correction of hyperbilirubinemia in the Gunn rat can be achieved with a low dose of 5 × 10(11) vp/kg by using an HDAd vector bearing a more potent UGT1A1 expression cassette. Furthermore, by using hydrodynamic injection of the improved HDAd vector, correction of hyperbilirubinemia in the Gunn rat can be achieved using an even lower dose of 5 × 10(10) vp/kg. Although hydrodynamic injection as performed in rats is not acceptable in humans, clinically attractive, minimally invasive methods have been successfully developed to mimic hydrodynamic injection of HDAd vector in non-human primates. Therefore, using an improved expression cassette combined with a more efficient method of vector delivery permits correction of hyperbilirubinemia in the Gunn rat using clinically relevant low HDAd doses and may thus pave the way to clinical application of HDAd vectors for Crigler-Najjar syndrome gene therapy.

  8. A Pilot Curriculum to Integrate Standardized Patient Simulation into Clinical Pastoral Education.

    Science.gov (United States)

    Ahmed, Rami A; Damore, Deborah R; Viti, Joseph F; Hughes, Patrick G; Miesle, Rebecca; Ataya, Ramsey; Atkinson, S Scott; Gable, Brad

    2016-06-01

    We describe a novel means of experiential learning for clinical pastoral care residents using standardized patient (SP) simulations. A prospective cohort study involving 7 clinical pastoral care residents was performed. All residents underwent 2 verbatim SP sessions and 2 simulation sessions. After all sessions, residents completed a self-evaluation. Faculty completed an evaluation and then provided a debriefing session to all residents. Performance ratings were globally higher on simulated scenarios when compared to the verbatim sessions. More research in the field of pastoral care is needed to validate the learned professional skills that enhance a comprehensive training program through the use of medical simulation, verbatim reports, and clinical pastoral education (CPE) competencies. Medical simulation provides a promising teaching methodology for the training of CPE residents. © The Author(s) 2015.

  9. Medical reference dosimetry using EPR measurements of alanine: Development of an improved method for clinical dose levels

    International Nuclear Information System (INIS)

    Helt-Hansen, Jakob; Andersen, Claus Erik; Rosendal, Flemming; Kofoed, Inger Matilde

    2009-01-01

    Electron spin resonance (EPR) is used to determine the absorbed dose of alanine dosimeters exposed to clinical photon beams in a solid-water phantom. Alanine is potentially suitable for medical reference dosimetry, because of its near water equivalence over a wide energy spectrum, low signal fading, non-destructive measurement and small dosimeter size. Material and Methods. A Bruker EMX-micro EPR spectrometer with a rectangular cavity and a measurement time of two minutes per dosimeter was used for reading of irradiated alanine dosimeters. Under these conditions a new algorithm based on scaling of known spectra was developed to extract the alanine signal. Results. The dose accuracy, including calibration uncertainty, is less than 2% (k=1) above 4 Gy (n=4). The measurement uncertainty is fairly constant in absolute terms (∼30 mGy) and the relative uncertainty therefore rises for dose measurements below 4 Gy. Typical reproducibility is <1% (k=1) above 10 Gy and <2% between 4 and 10 Gy. Below 4 Gy the uncertainty is higher. A depth dose curve measurement was performed in a solid-water phantom irradiated to a dose of 20 Gy at the maximum dose point (dmax) in 6 and 18 MV photon beams. The typical difference between the dose measured with alanine in solid water and the dose measured with an ion chamber in a water tank was about 1%. A difference of 2% between 6 and 18 MV was found, possibly due to non-water equivalence of the applied phantom. Discussion. Compared to previously published methods the proposed algorithm can be applied without normalisation of phase shifts caused by changes in the g-value of the cavity. The study shows that alanine dosimetry is a suitable candidate for medical reference dosimetry especially for quality control applications

  10. PROFOUND AND SEXUALLY DIMORPHIC EFFECTS OF CLINICALLY-RELEVANT LOW DOSE SCATTER IRRADIATION ON THE BRAIN AND BEHAVIOR

    Directory of Open Access Journals (Sweden)

    Anna eKovalchuk

    2016-06-01

    Full Text Available Irradiated cells can signal damage and distress to both close and distant neighbors that have not been directly exposed to the radiation (naïve bystanders. While studies have shown that such bystander effects occur in the shielded brain of animals upon body irradiation, their mechanism remains unexplored. Observed effects may be caused by some blood-borne factors; however they may also be explained, at least in part, by very small direct doses received by the brain that result from scatter or leakage. In order to establish the roles of low doses of scatter irradiation in the brain response, we developed a new model for scatter irradiation analysis whereby one rat was irradiated directly at the liver and the second rat was placed adjacent to the first and received a scatter dose to its body and brain. This work focuses specifically on the response of the latter rat brain to the low scatter irradiation dose. Here, we provide the first experimental evidence that very low, clinically relevant doses of scatter irradiation alter gene expression, induce changes in dendritic morphology, and lead to behavioral deficits in exposed animals. The results showed that exposure to radiation doses as low as 0.115 cGy caused changes in gene expression and reduced spine density, dendritic complexity, and dendritic length in the prefrontal cortex tissues of females, but not males. In the hippocampus, radiation altered neuroanatomical organization in males, but not in females. Moreover, low dose radiation caused behavioral deficits in the exposed animals. This is the first study to show that low dose scatter irradiation influences the brain and behavior in a sex-specific way.

  11. Natural language processing systems for capturing and standardizing unstructured clinical information: A systematic review.

    Science.gov (United States)

    Kreimeyer, Kory; Foster, Matthew; Pandey, Abhishek; Arya, Nina; Halford, Gwendolyn; Jones, Sandra F; Forshee, Richard; Walderhaug, Mark; Botsis, Taxiarchis

    2017-09-01

    We followed a systematic approach based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses to identify existing clinical natural language processing (NLP) systems that generate structured information from unstructured free text. Seven literature databases were searched with a query combining the concepts of natural language processing and structured data capture. Two reviewers screened all records for relevance during two screening phases, and information about clinical NLP systems was collected from the final set of papers. A total of 7149 records (after removing duplicates) were retrieved and screened, and 86 were determined to fit the review criteria. These papers contained information about 71 different clinical NLP systems, which were then analyzed. The NLP systems address a wide variety of important clinical and research tasks. Certain tasks are well addressed by the existing systems, while others remain as open challenges that only a small number of systems attempt, such as extraction of temporal information or normalization of concepts to standard terminologies. This review has identified many NLP systems capable of processing clinical free text and generating structured output, and the information collected and evaluated here will be important for prioritizing development of new approaches for clinical NLP. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Dose to the Developing Dentition During Therapeutic Irradiation: Organ at Risk Determination and Clinical Implications

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Reid F., E-mail: Reid.Thompson@uphs.upenn.edu [Center for Proton Therapy, Paul Scherrer Institute, Villigen (Switzerland); Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania (United States); Schneider, Ralf A., E-mail: ralf.schneider@psi.ch [Center for Proton Therapy, Paul Scherrer Institute, Villigen (Switzerland); Albertini, Francesca; Lomax, Antony J.; Ares, Carmen; Goitein, Gudrun [Center for Proton Therapy, Paul Scherrer Institute, Villigen (Switzerland); Hug, Eugen B. [Center for Proton Therapy, Paul Scherrer Institute, Villigen (Switzerland); ProCure Therapy Centers, New York, New York (United States)

    2013-05-01

    Purpose: Irradiation of pediatric facial structures can cause severe impairment of permanent teeth later in life. We therefore focused on primary and permanent teeth as organs at risk, investigating the ability to identify individual teeth in children and infants and to correlate dose distributions with subsequent dental toxicity. Methods and Materials: We retrospectively reviewed 14 pediatric patients who received a maximum dose >20 Gy(relative biological effectiveness, RBE) to 1 or more primary or permanent teeth between 2003 and 2009. The patients (aged 1-16 years) received spot-scanning proton therapy with 46 to 66 Gy(RBE) in 23 to 33 daily fractions for a variety of tumors, including rhabdomyosarcoma (n=10), sarcoma (n=2), teratoma (n=1), and carcinoma (n=1). Individual teeth were contoured on axial slices from planning computed tomography (CT) scans. Dose-volume histogram data were retrospectively obtained from total calculated delivered treatments. Dental follow-up information was obtained from external care providers. Results: All primary teeth and permanent incisors, canines, premolars, and first and second molars were identifiable on CT scans in all patients as early as 1 year of age. Dose-volume histogram analysis showed wide dose variability, with a median 37 Gy(RBE) per tooth dose range across all individuals, and a median 50 Gy(RBE) intraindividual dose range across all teeth. Dental follow-up revealed absence of significant toxicity in 7 of 10 patients but severe localized toxicity in teeth receiving >20 Gy(RBE) among 3 patients who were all treated at <4 years of age. Conclusions: CT-based assessment of dose distribution to individual teeth is feasible, although delayed calcification may complicate tooth identification in the youngest patients. Patterns of dental dose exposure vary markedly within and among patients, corresponding to rapid dose falloff with protons. Severe localized dental toxicity was observed in a few patients receiving the

  13. Comparison of radiation dose, workflow, patient comfort and financial break-even of standard digital radiography and a novel biplanar low-dose X-ray system for upright full-length lower limb and whole spine radiography.

    Science.gov (United States)

    Dietrich, Tobias J; Pfirrmann, Christian W A; Schwab, Alexander; Pankalla, Katja; Buck, Florian M

    2013-07-01

    To compare the radiation dose, workflow, patient comfort, and financial break-even of a standard digital radiography and a biplanar low-dose X-ray system. A standard digital radiography system (Ysio, Siemens Healthcare, Erlangen, Germany) was compared with a biplanar X-ray unit (EOS, EOS imaging, Paris, France) consisting of two X-ray tubes and slot-scanning detectors, arranged at an angle of 90° allowing simultaneous vertical biplanar linear scanning in the upright patient position. We compared data of standing full-length lower limb radiographs and whole spine radiographs of both X-ray systems. Dose-area product was significantly lower for radiographs of the biplanar X-ray system than for the standard digital radiography system (e.g. whole spine radiographs; standard digital radiography system: 392.2 ± 231.7 cGy*cm(2) versus biplanar X-ray system: 158.4 ± 103.8 cGy*cm(2)). The mean examination time was significantly shorter for biplanar radiographs compared with standard digital radiographs (e.g. whole spine radiographs: 449 s vs 248 s). Patients' comfort regarding noise was significantly higher for the standard digital radiography system. The financial break-even point was 2,602 radiographs/year for the standard digital radiography system compared with 4,077 radiographs/year for the biplanar X-ray unit. The biplanar X-ray unit reduces radiation exposure and increases subjective noise exposure to patients. The biplanar X-ray unit demands a higher number of examinations per year for the financial break-even point, despite the lower labour cost per examination due to the shorter examination time.

  14. Comparison of radiation dose, workflow, patient comfort and financial break-even of standard digital radiography and a novel biplanar low-dose X-ray system for upright full-length lower limb and whole spine radiography

    Energy Technology Data Exchange (ETDEWEB)

    Dietrich, Tobias J.; Pfirrmann, Christian W.A.; Pankalla, Katja; Buck, Florian M. [Orthopedic University Hospital Balgrist, Department of Radiology, Zurich (Switzerland); University of Zurich, Zurich (Switzerland); Schwab, Alexander [University of Zurich, Zurich (Switzerland); Orthopedic University Hospital Balgrist, Department of Finances, Zurich (Switzerland)

    2013-07-15

    To compare the radiation dose, workflow, patient comfort, and financial break-even of a standard digital radiography and a biplanar low-dose X-ray system. A standard digital radiography system (Ysio, Siemens Healthcare, Erlangen, Germany) was compared with a biplanar X-ray unit (EOS, EOS imaging, Paris, France) consisting of two X-ray tubes and slot-scanning detectors, arranged at an angle of 90 allowing simultaneous vertical biplanar linear scanning in the upright patient position. We compared data of standing full-length lower limb radiographs and whole spine radiographs of both X-ray systems. Dose-area product was significantly lower for radiographs of the biplanar X-ray system than for the standard digital radiography system (e.g. whole spine radiographs; standard digital radiography system: 392.2 {+-} 231.7 cGy*cm{sup 2} versus biplanar X-ray system: 158.4 {+-} 103.8 cGy*cm{sup 2}). The mean examination time was significantly shorter for biplanar radiographs compared with standard digital radiographs (e.g. whole spine radiographs: 449 s vs 248 s). Patients' comfort regarding noise was significantly higher for the standard digital radiography system. The financial break-even point was 2,602 radiographs/year for the standard digital radiography system compared with 4,077 radiographs/year for the biplanar X-ray unit. The biplanar X-ray unit reduces radiation exposure and increases subjective noise exposure to patients. The biplanar X-ray unit demands a higher number of examinations per year for the financial break-even point, despite the lower labour cost per examination due to the shorter examination time. (orig.)

  15. Resource utilization after introduction of a standardized clinical assessment and management plan.

    Science.gov (United States)

    Friedman, Kevin G; Rathod, Rahul H; Farias, Michael; Graham, Dionne; Powell, Andrew J; Fulton, David R; Newburger, Jane W; Colan, Steven D; Jenkins, Kathy J; Lock, James E

    2010-01-01

    A Standardized Clinical Assessment and Management Plan (SCAMP) is a novel quality improvement initiative that standardizes the assessment and management of all patients who carry a predefined diagnosis. Based on periodic review of systemically collected data the SCAMP is designed to be modified to improve its own algorithm. One of the objectives of a SCAMP is to identify and reduce resource utilization and patient care costs. We retrospectively reviewed resource utilization in the first 93 arterial switch operation (ASO) SCAMP patients and 186 age-matched control ASO patients. We compared diagnostic and laboratory testing obtained at the initial SCAMP clinic visit and control patient visits. To evaluate the effect of the SCAMP over time, the number of clinic visits per patient year and echocardiograms per patient year in historical control ASO patients were compared to the projected rates for ASO SCAMP participants. Cardiac magnetic resonance imaging (MRI), stress echocardiogram, and lipid profile utilization were higher in the initial SCAMP clinic visit group than in age-matched control patients. Total echocardiogram and lung scan usage were similar. Chest X-ray and exercise stress testing were obtained less in SCAMP patients. ASO SCAMP patients are projected to have 0.5 clinic visits and 0.5 echocardiograms per year. Historical control patients had more clinic visits (1.2 vs. 0.5 visits/patient year, P<.01) and a higher echocardiogram rate (0.92 vs. 0.5 echocardiograms/patient year, P<.01) Implementation of a SCAMP may initially lead to increased resource utilization, but over time resource utilization is projected to decrease.

  16. Microbial air quality and standard precaution practice in a hospital dental clinic.

    Science.gov (United States)

    Luksamijarulkul, Pipat; Panya, Navapan; Sujirarat, Dusit; Thaweboon, Sroisiri

    2009-12-01

    A cross-sectional study was carried out to assess standard precaution practices among dental personnel and to investigate microbial counts in indoor air samples collected from a hospital dental clinic before and during dental works. Thirty dental personnel who voluntarily participated were interviewed using a questionnaire towards demographic information and standard precaution practices between May and August 2007. Additionally, 138 indoor air samples (72 from dental treatment units, 48 from dental supporting units and offices and 18 from patient waiting area) were collected before and during dental works for 6 days (Monday to Saturday) to investigate bacterial and fungal counts. Data were analyzed by using descriptive statistics. Paired t-test was used for analyzing the difference of mean + standard deviation between microbial counts before and during dental procedures. The statistical significance was expressed in term of p-value and the critical level was set at alpha = 0.05. The results revealed that standard precaution practices towards wearing personal protective equipments regularly during dental procedures ranged from 50% to 100%, whereas, cleaning and disinfecting dental unit after each patient treatment and cleaning dental unit water lines with antiseptics every week were done regularly only 36.7%. The mean score of standard precaution was 8.4 +/- 2.5 (moderate level, total score of 13). The means of bacterial and fungal counts in air samples collected from dental treatment units significantly increased during dental procedures when compared with those collected before dental works (p 0.05. This study demonstrated the moderate level of standard precaution practice score among studied dental personnel and significantly higher microbial counts (bacterial and fungal counts) in air samples collected from dental treatment units during dental procedures were demonstrated. To reduce the occupational risk among this group, standard precaution practices should be

  17. Clinical outcome of stereotactic body radiotherapy for primary and oligometastatic lung tumors: a single institutional study with almost uniform dose with different five treatment schedules

    International Nuclear Information System (INIS)

    Aoki, Masahiko; Hatayama, Yoshiomi; Kawaguchi, Hideo; Hirose, Katsumi; Sato, Mariko; Akimoto, Hiroyoshi; Fujioka, Ichitaro; Ono, Shuichi; Tsushima, Eiki; Takai, Yoshihiro

    2016-01-01

    To evaluate clinical outcomes of stereotactic body radiotherapy (SBRT) for localized primary and oligometastatic lung tumors by assessing efficacy and safety of 5 regimens of varying fraction size and number. One-hundred patients with primary lung cancer (n = 69) or oligometastatic lung tumors (n = 31), who underwent SBRT between May 2003 and August 2010, were included. The median age was 75 years (range, 45–88). Of them, 98 were judged to have medically inoperable disease, predominantly due to chronic illness or advanced age. SBRT was performed using 3 coplanar and 3 non-coplanar fixed beams with a standard linear accelerator. Fraction sizes were escalated by 1 Gy, and number of fractions given was decreased by 1 for every 20 included patients. Total target doses were between 50 and 56 Gy, administered as 5–9 fractions. The prescribed dose was defined at the isocenter, and median overall treatment duration was 10 days (range, 5–22). The median follow-up was 51.1 months for survivors. The 3-year local recurrence rates for primary lung cancer and oligometastasis was 6 % and 3 %, respectively. The 3-year local recurrence rates for tumor sizes ≤3 cm and >3 cm were 3 % and 14 %, respectively (p = 0.124). Additionally, other factors (fraction size, total target dose, and BED 10 ) were not significant predictors of local control. Radiation pneumonia (≥ grade 2) was observed in 2 patients. Radiation-induced rib fractures were observed in 22 patients. Other late adverse events of greater than grade 2 were not observed. Within this dataset, we did not observe a dose response in BED 10 values between 86.4 and 102.6 Gy. SBRT with doses between 50 and 56 Gy, administered over 5–9 fractions achieved acceptable tumor control without severe complications

  18. Randomized clinical trial of extended versus single-dose perioperative antibiotic prophylaxis for acute calculous cholecystitis

    NARCIS (Netherlands)

    Loozen, C. S.; Kortram, K.; Kornmann, V. N. N.; van Ramshorst, B.; Vlaminckx, B.; Knibbe, C. A. J.; Kelder, J. C.; Donkervoort, S. C.; Nieuwenhuijzen, G. A. P.; Ponten, J. E. H.; van Geloven, A. A. W.; van Duijvendijk, P.; Bos, W. J. W.; Besselink, M. G. H.; Gouma, D. J.; van Santvoort, H. C.; Boerma, D.

    2017-01-01

    Many patients who have surgery for acute cholecystitis receive postoperative antibiotic prophylaxis, with the intent to reduce infectious complications. There is, however, no evidence that extending antibiotics beyond a single perioperative dose is advantageous.