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OBJECTIVE To analyze historical radiation dose data from fluoroscopy users at a major university medical center and compare the impact of two alternate dose monitoring methodologies. MATERIALS AND METHODS Interventional radiologists have traditionally worn two radiation monitoring badges to estimate their radiation dose. This study evaluates if a single badge monitoring system can reduce the administrative burden of radiation monitoring without negatively impacting safety or compliance. This study reviewed the dose history data for a 10-y period including 114,500 individual dose measurements. These individuals were each issued two badges for each wear period, including one worn at the collar (outside a protective garment) and one worn at the chest or waist (beneath a protective garment). The dose for each of the badges was derived from the database of personnel dose records. Badges that could be clearly identified as improperly worn were excluded from the study. The EDE as assigned from the two-badge system and as derived from the wear of the collar badge only were both compared to the thresholds for ALARA notifications currently in use. RESULTS Calculated EDE values are an average of 2.7 times higher when applying a one-badge system as compared to a two-badge system. This is observed to result in a slight increase in the ALARA notification frequency (excluding badges improperly worn in the two-badge system). The overall increase in notification frequency is small because notifications are dominated by dose to the lens of the eye. CONCLUSION Although providing less accurate personnel dose estimates relative to a two-badge system, the use of a one-badge monitoring system for fluoroscopy users may have a minimal effect on radiation dose records and "as low as (is) reasonably achievable" (ALARA) notifications, with potentially significant savings in notifications due to improper badge wear, volume of radiation monitoring badges handled, and cost of the radiation monitoring system.

The aim of CONFIDENCE WP2 is to improve the situation awareness in the early phase of a nuclear accident by trying to reduce the uncertainty in individual dose assessment when dealing with external and internal exposures. Main WP2 research actions to improve external dosimetry in this emergency frame were the development of destruction-free protocols using electronic components in smartphones for external dose measurements, Monte Carlo (MCNP) calculations for organ dose assessment with associated uncertainties and the organization of a workshop for integration of biodosimetry into emergency response. On the other hand, one of the main concerns after the release of radioactive material in case of a nuclear reactor accident is the intake of radioiodines in workers and population. A smartphone/tablet application for direct calculation of thyroid doses from monitoring data of the content of 131I (and 132I) in the thyroid was developed during the project (Prototype of processing unit for thyroid dose monitor [IDOSE]). Up to date age-dependent ICRP dose per content values are used by this tool, allowing a rapid screening of exposed persons. A sensitivity analysis on thyroid doses was carried out, considering 16 exposure scenarios leading to 16 different dose estimates, using ICRP56/119 (ICRP60) vs. ICRP130/137 iodine models for adults, varying the time of intake, the time pattern (acute vs. chronic) and considering not well defined relative abundance of short-lived radioiodines and 132Te. Real cases of Europeans contaminated in Japan shortly after the Fukushima NPP accident (low doses), and artificial cases of high doses generated to see the impact of the different parameters in this study, were used for applying this multi-intake scenario approach. Main conclusions of the study are presented here.

The Chernobyl accident on 26 April 1986 led to a sharp increase in thyroid cancer (TC) incidence in the individuals exposed to radiation in childhood. The major risk factor for TC was exposure to Iodine-131 (131I). Here, we estimated the thyroid doses due to 131I intake for 2041 participants of the genome-wide association study of TC in Belarusian people exposed to radioactive fallout from the Chernobyl accident. The following parameter-values specially developed in this study were used to estimate individual thyroid doses: (i) scaling factors for adjustment of the model-based doses, (ii) age and gender diet to characterize 131I intake, and (iii) area-, age- and gender-specific S-values for the thyroid gland per 131I decay in the thyroid. The most reliable doses were calculated for 103 people with measured 131I thyroid activity (the arithmetic mean of 1.2 Gy, median 0.52 Gy), and 275 individuals with detailed residential history and dietary data (the arithmetic mean of 0.41 Gy, median 0.24 Gy). The arithmetic mean of thyroid doses among all study participants was 0.23 Gy (median 0.082 Gy); the highest individual dose was 9.0 Gy. Special attention was paid to the reliability and validity of the obtained estimates, in particular for the individuals without 131I thyroid activity measurements and individual data on residential history and diet, by comparing those with the doses from other post-Chernobyl epidemiological studies. Overall, the doses estimated in the current study were in reasonable agreement with previously reported thyroid doses. These doses will be used in the genome-wide association study of TC in people exposed in Belarus to 131I after the Chernobyl accident.

Background: Peptide receptor radionuclide therapy (PRRT) is an emerging therapeutic option for the treatment of neuroendocrine tumors (NETs), and the number of publications in this field has been increasing in recent years. The aim of the present study was to present the research status and summarize the key topics through bibliometric analysis of published PRRT literature.Methods: A literature search for PRRT research from 2000 to 2019 was conducted using the Science Citation Index Expanded of Web of Science Core Collection (limited to SCIE) on August 4, 2020. The VOSviewer, R-bibliometrix, and CiteSpace software were used to conduct the bibliometric analysis.Results: From 2000 to 2019, a total of 681 publications (523 articles and 158 reviews) were retrieved. Annual publication outputs grew from three to 111 records. Germany had the largest number of publications, making the largest contribution to the field (n = 151, 22.17%). Active cooperation between countries/regions was observed. Kwekkeboom from the Erasmus Medical Center is perhaps a key researcher in the field of PRRT. The European Journal of Nuclear Medicine and Molecular Imaging and Journal of Nuclear Medicine ranked first for productive (n = 84, 12.33%) and co-cited (n = 3,438) journals, respectively. Important topics mainly included matters related to the efficacy of PRRT (e.g., 90Y-dotatoc and 177Lu-dotatate), the long-term adverse effects of PRRT (e.g., hematologic and renal toxicities), standardization of NETs and PRRT in practice, the development of medical imaging techniques, and the individual dose optimization of PRRT.Conclusion: Using bibliometric analysis, we gained deep insight into the global status and trends of studies investigating PRRT for the first time. The PRRT field is undergoing a period of rapid development, and our study provides a valuable reference for clinical researchers and practitioners.

Chemotherapy-induced neuropathy, ranking among the most common toxic neuropathies, primarily affects the sensory nerve modalities. Taxanes and oxaliplatin commonly cause an acute pain problem, something that presents soon after each individual dose and then generally improves over a course of days. In addition, these drugs and several other neurotoxic chemotherapy drugs commonly cause a more gradually appearing and more chronic neuropathy that primarily involves distal extremities. There are a number of similarities regarding the peripheral neuropathy caused by many chemotherapy drugs, noting that there are some distinct differences in them, also. When neurotoxic chemotherapy is stopped, neuropathy problems often improve. However, neuropathy can become a prominent problem for years, in some patients, leading to marked disabilities.

Dosimetric monitoring is useful to limit exposures to ionising radiation in medical occupational settings, and reduce subsequent health risks. Scientific literatures, such as the UNSCEAR report 2017 and International Atomic Energy Agency Report 2014b, updated information on this subject; however, few African works have been found. This is the reason why we undertook this study, which summarises existing information on monitoring external radiation exposure doses for the whole body, using data from medical workers on this continent. Using standard terms and combining different keyword searches for radiation dose monitoring among radiology healthcare workers in Africa, from the titles, abstracts, and full texts, we found 3139 articles in the PubMed/MEDLINE, Google Scholar and INIS databases. Two reviewers screened the retrieved publications based on predefined eligibility criteria to identify relevant studies, extract key information from each, and summarise the data in table form. A total of 20 potentially relevant articles were identified. Among these 20 articles, 15 reported the overall average annual effective dose. Studies included in this systematic review represent an inventory of the radiation protection of medical workers in various African countries, with a focus on the monitoring of occupational radiation exposure. The size of studied populations ranged between 81 and 5152 occupational exposed workers. The mean annual effective doses ranged from 0.44 to 8.20 mSv in all specialities of medical sectors, while diagnostic radiology ranged from 0.07 to 4.37 mSv. For the nuclear medicine and radiotherapy from medical groups, the mean annual effective dose varied between 0.56 and 6.30 mSv. Industrial and research/teaching sectors data varied between 0.38 to 19.40 mSv. In conclusion, more studies implemented on dosimetric monitoring in Africa are needed to get a real picture of occupational exposure in the continent.

We postulated that a contiguous rectal dose-volume threshold curve obtained via a best mathematical fit of the toughest literature recommended dose-volume thresholds could be deemed as “safe” related to the risk of rectal toxicity. The practicality of restricting rectal doses to such ideal volume thresholds in clinical practice was tested by comparing data collected from a pool of prostate patients treated with external beam radiation therapy (EBRT) in our institution. Available rectal dose-volume constraint recommendation in prostate EBRT was collected. At each dose level, the toughest recommended volume limit was identified and an ideal dose-volume threshold curve was generated using a best mathematical fit. Rectal dose-volume data on 105 prostate patients treated to 75.6 Gy dose with intensity modulated radiation therapy (IMRT) in our institution were retrospectively reviewed. The “ideal” rectal dose-volume threshold curve is defined by V 75 ≤ 7%, V 70 ≤ 11%, V 65 ≤ 15%, V 60 ≤ 20%, V 50 ≤ 30%, V 40 ≤ 43%, and V 30 ≤ 60%. At doses larger or equal to 65 Gy, our patient averaged dose-volume histograms (DVHs) for all groups converged with the ideal curve. At intermediate and low doses (less than 60 Gy), higher volumes of rectum were irradiated than described by the hypothetical curve, with pelvic group receiving more rectal dose than prostate only group respectively. Rectal mean dose correlated strongly with V 40 values (R 2 = 0.84). Our “ideal” rectal dose-volume curve generated from literature dose-volume thresholds in the most stringent manner is realistic and achievable at high doses (≥60 Gy) and not realistic at intermediate and low doses (≤50 Gy). Standardizing rectal definition and dose-volume metrics will make published analyses and dose-volume constraint recommendations easier to follow.

Measurement of individual radiation dose is crucial for planning protective measures after nuclear accidents. The purpose of this article is to explain the various initiatives taken after the TEPCO Fukushima Daiichi Nuclear Power Plant accident, including the D-shuttle project wherein residents from affected areas wore a personal dosimeter to measure their own external exposure. The experience in Fukushima revealed several issues such as gaining residents’ trust and ensuring appropriate communication of the measured data. The D-shuttle project also revealed that obtaining individual dose measurement data had 2 purposes, as the information obtained was to be utilized by the residents for self-protection and by the authorities for deriving the dose distribution of the population to aid in designing large-scale protection measures. The lessons learned are that both the residents and the authorities need to understand and share the meaning of individual dose measurements and the measurement results must be used with due respect for the residents’ privacy and other concerns.

Free drug concentration (Cf) is instantaneous and susceptible to sampling time, which can confuse clinicians and cause them to adjust the dosage regimen. In the present work, we indicated a new parameter, the plasma protein binding (PPB) of clinical plasma samples, and discussed its application in TDM (Therapeutic Drug Monitoring). Furthermore, carbamazepine was selected as a model drug to develop a simple pretreatment method for the determination of PPB, in which Cf and Ct can be simultaneously analyzed in one plasma sample using a single device. Our results demonstrated that this proposed method exhibited some advantages, including perfect recovery (approximately 100%) and high precision (CV% < 3.0%). Furthermore, it achieved successful application in real plasma samples. Individual differences in PPB (from 10.1–68.9%) were among patients, and in additon, between the patients and healthy people (p < 0.05). Moreover, there was a weak correlation between Ct and Cf (r2 = 0.470 and p < 0.05), so the Cf of CBZ cannot be estimated from Ct. However, the primary cause of the variability of Cf is the change in PPB. As a consequence, applying PPB to guide individual dose adjustment is more accurate and more scientific than using Cf or Ct.

Aims To assess incremental and total patient exposure from clinical SPECT/CT imaging by means of effective dose estimations with regards to different protocols and SPECT/CT systems. Materials and methods Consecutive patient exposure levels were documented prospectively from SPECT/CT operations at three European imaging centers. Documentation included the volume-weighted computed tomography (CT) dose index, the CT dose length product (DLP) and the amount of applied radiopharmaceutical. SPECT/CT examinations were categorized regionally into head, neck, myocardium, thorax, abdomen, extremities and whole-body. Effective dose from the CT (EDCT) was estimated from the DLP using gender specific conversion factors. EDSPECT was estimated from the injected activity levels and corresponding conversion factors (ICRP 106). Results This study included 678 SPECT/CT examinations. EDCT per indication and EDSPECT per tracer ranged from 0.01 mSv to 7.4 mSv and from 1.1 mSv to 12.2 mSv, respectively. In general, EDSPECT contributed most to overall patient exposure. Total EDSPECT/CT averaged across all protocol categories was 6.7 mSv. Conclusion Total patient exposure from clinical SPECT/CT is 7 mSv on average. Individual dose levels vary with the clinical indication and on-site protocol parameters.

The aim of the study was personnel dose assessment due to the normal operations with the artificial radiation sources. The article is based on the data from the Unified System of Individual Dose Control and Voronezh Region’s radiation-hygienic passport. The data from No.1-DOZ “Information on personnel exposure doses under normal operation of technogenic ionizing radiation sources” and over a period of 2006-2010 years were analyzed. In 2006-2015, the number of organizations, which submitted form No.1-DOZ “Information on personnel exposure doses under normal operation of technogenic ionizing radiation sources”, increased from 175 to 229. In amount of the radiation facilities, Novovoronezh Nuclear Power Plant is the first. Novovoronezh NPP has 1512 sources, which amounts to 51,9% from all sources in Voronezh Region (2915). Health care facilities have 869 radiation sources or 29,8%. X-ray machines are the main part of these sources (844 health care facilities or 97,1% of all medical sources). Industrial sources occupy third place with 305 facilities or 10,5% of all considered sources. In 2015, according to the data from Voronezh Region’s radiation-hygienic passport, the number of “A” group personnel were 4237, the number of “B” group personnel were 2341. The average individual dose for personnel was over the range from 0.66 to 2.02 mSv. Collective dose was from 4.16 to 11.79 man-sieverts per year. The increase of number of the radiation sources has attended with the decrease of individual and collective doses. The most likely it is related to using the modern facilities. In 2015, the maximum value of the average individual dose of “A” group personnel was registered in Voronezh regional hospital (6.17 mSv y–1). There are medical facilities with unsealed and sealed sources in this hospital. In 2006-2015, the average individual doses of personnel of all radiation facilities that use radiation sources in Voronezh region were significantly below the dose limits established by the Radiation Safety Standards NRB-99/2009.

According to results of in-depth studies, the risk of the radiation-induced cataract is higher than it was considered earlier. In April 2011, ICRP released a statement on the tissue reactions. The statement recommends that for the case of for occupational exposure in planned exposure situations, an equivalent dose for the lens of the eye should be less than 20 mSv in a year, averaged over the defined periods of 5 years, with no single year exceeding the value of 50 mSv. In this regard, the new standard IAEA № GSR Part 3 provides the dose limit of 20 mSv in a year for occupational exposure for the lens of the eye. The dosimetric data on levels of exposure for personnel in the Russian Federation is practically absent. This paper performs a preliminary evaluation of equivalent dose for the lens of the eye for personnel working in X-ray operating rooms of medical facilities in Saint Petersburg and Kazan. This group of personnel was selected because of the fact that methodic of carrying out procedures forces medical staff to be not only in the zone of scattered radiation but also in the X-ray beam. This fact significantly increases exposure doses for the personnel. It is shown that actual annual dose can exceed the new dose limit (the highest recorded value Нр(3) in 3 months of work was 8,6 mSv). We made a conclusion on the necessity of the lens of the eye dose monitoring amongst interventional specialists on conditions that new limits will be established in the Russian Federation. The Russian and foreign dosimeters for measurement of individual dose equivalent for the lens of the eye Нр(3) which have been registered in the Russian State Register of Measuring Instruments, are descrivebed in the paper.

Objective: Migraine is one of the most frequent disabling neurological conditions and very bad headache with a major impact on the patient's quality of life. The objective of this study was to evaluate the effectiveness of Prednisolone in treating migraine. Methods: A cross sectional, hospital-based study was conducted. All patients (1020) were received Prednisolone 0.5 mg/kg/day for 7 days followed by tapering by 1 tablet (5 mg) every 7 days. The patients were followed minimally for six months after receiving treatment. Results: All patients responded to the treatment and all their associated symptoms disappeared. We think this approach is the best one for treating migraine. Conclusion: We think that our approach is the best one in treating migraine, so our recommendation is to use steroids (Prednisolone tablets, in a dose of 0.5 mg / kg/day for 7 days, followed by tapering by 1 tablet (5 mg) every 7 days) as a protocol for the treatment of migraine. The individual dose adjustment is required in certain cases. From this study we conclude that, firstly we can say we have got the answer of the big question: what is migraine. Secondly, we think we present a nice explanation of the vascular phenomenon associated with migraine. Number third, we introduce new common symptom associated with migraine. Lastly we introduce new and effective treatment for migraine.

AimsMedication errors are perhaps the most common threat to patient safety.1 Children are particularly at risk because of variations in age and weight necessitating individual dose calculation for each patient; doses that are ten times the correct amount are occasionally given and can be life-threatening.2 Since 2015 the hospital has been seeking, as part of a Regional Quality initiative, to improve safety related to paracetamol.MethodsPrevious work involved clarification of IV paracetamol dosing for neonates and children under 10 kg with procurement of 100 mg in 10 ml vials, as well as introduction of a ‘ready-reckoner’ reference chart for prescribing, preparation and administration inserted into each BNFC across the hospital. In September 2018, we implemented a new prescribing aide sticker into kardexes in an effort to reduce IV administration errors. We then audited whether these interventions had led to an overall reduction in adverse incidents related to paracetamol.ResultsWe demonstrated a progressive reduction in adverse incidents over the past four years; it has now been more than 1000 days since the last reported serious adverse incident related to paracetamol. A snapshot audit of prescribing showed that 100% of patients were prescribed a safe dose of paracetamol by either age or weight. There was however considerable variation in dosing for enteral prescribing (8.2–18.8 mg/kg), with the majority of children (74%) being dosed according to age, despite weight being available at time of prescription. Introduction of the paracetamol prescribing aide sticker received overwhelmingly positive feedback from both medical and nursing staff, and has now been implemented for all children requiring regular IV paracetamol.ConclusionsAnaesthetics were the most commonly implicated specialty in paracetamol errors in our institution. Enteral dosing by age banding in hospital carries the potential for some children to be significantly under-dosed leading to sub-therapeutic drug levels, or even inadvertently over-dosed for more complex children who are underweight for age. We would therefore recommend dosing of enteral paracetamol by weight, when available, in hospital. Substantial improvement in paracetamol safety can be achieved through implementation of prescribing and administration aides to reduce likelihood of human error.ReferencesEyers S, Fingleton J, Perrin K, Beasley R. Proposed MHRA changes to UK children’s paracetamol dosing recommendations: modelling study. J R Soc Med 2012;105:263–9.Kaufmann J, Laschat M, Wappler F. Medication Errors in Paediatric Emergencies: A Systematic Analysis. Dtsch Arztebl Int 2012;109:609–616.

Bayesian forecasting (BF) methods for tobramycin dose individualisation has not seen widespread clinical adoption, despite being endorsed by clinical practice guidelines. Several freeware and commercial programmes using BF methods are available to support personalised dosing. This study evaluated exposure estimates, dose recommendations, and predictive performance compared with current clinical practice. Data from 105 patients (50 adults and 55 children) with cystic fibrosis who received intravenous tobramycin treatment and had paired concentration–time measurements were analysed using (1) log-linear regression analysis, and (2) three BF programmes: TDMx, InsightRX, and DoseMe. Exposure estimates and dose recommendations were compared using the Wilcoxon signed-rank test and Bland–Altman analysis. Predictive performance of BF programmes was compared based on bias and imprecision. Median estimated tobramycin exposure with current clinical practice was significantly lower (87.8 vs. 92.5, 94.0 and 90.3 mg h l−1; p ≤ 0.01), hence median subsequent dose recommendations were significantly higher (10.1 vs. 9.4, 9.4 and 9.2 mg kg−1; p ≤ 0.01) compared with BF programmes. Furthermore, median relative dose-adjustment differences were higher in adults (> 10%) compared with children (4.4–7.8%), and differences in individual dose recommendations were > 20% on 19.1–27.4% of occasions. BF programmes showed low bias (

PURPOSE: To study the impact on radiation exposure to staff through the use of an original perineal shield during low-dose-rate prostate brachytherapy. MATERIAL AND METHODS: We designed a 1 mm thick stainless steel shield that duplicates and is able to slide directly over a standard commercialized prostate brachytherapy grid. We then analyzed the post-procedure exposure in 15 consecutive patients who underwent Iodine-125 seed placement. Measurements were performed with and without the shield in place at fixed locations relative to the grid template. Endpoints were analyzed using the paired two-sample t-test, with statistical significance defined as a p-value < 0.05. RESULTS: The exposure at the midline grid template ranged from 0.144-0.768 mSv/hr without the shield, and 0.038-0.144 mSv/hr with the shield (p < 0.0001). The exposure 10 cm left of the grid template was 0.134-0.576 mSv/hr without the shield, and 0.001-0.012 mSv/hr with the shield (p < 0.0001). The exposure 10 cm right of the grid template was 0.125-0.576 mSv/hr without the shield, and 0.001-0.012 mSv/hr with the shield (p < 0.0001). The median reduction of exposure at the grid was 76% midline, 98.5% left, and 99% right. Similarly, each individual dose rate was recorded at 25 cm from the perineum, both with and without shield. The median reduction of exposure 25 cm from the perineum was 73.7% midline, 77.7% left and 81.6% right (p < 0.0001). CONCLUSIONS: Our novel shield took seconds to install and was non-restrictive during the procedure, and provided at least a four-fold reduction in radiation exposure to the brachytherapist.

Attention-deficit/hyperactivity disorder (ADHD) is a chronic psychiatric disorder characterized by hyperactivity and/or inattention and is often associated with a substantial impact on psychosocial functioning. Methylphenidate (MPH), a central nervous system stimulant, is commonly used for pharmacological treatment of adults and children with ADHD. Current practice guidelines recommend optimizing MPH dosage to individual patient needs; however, the clinical benefits of individual dose optimization compared with fixed-dose regimens remain unclear. Here we review the available literature on MPH dose optimization from clinical trials and real-world experience on ADHD management. In addition, we report safety and efficacy data from the largest MPH modified-release long-acting Phase III clinical trial conducted to examine benefits of dose optimization in adults with ADHD. Overall, MPH is an effective ADHD treatment with a good safety profile; data suggest that dose optimization may enhance the safety and efficacy of treatment. Further research is required to establish the extent to which short-term clinical benefits of MPH dose optimization translate into improved long-term outcomes for patients with ADHD.

Objectives: Evaluation of radiation efficiency of dual source high-pitch (DSHP) chest CT in comparison to single source technique with special regards to individual patient anatomy. Methods: 150 consecutive patients who underwent chest CT with automated tube current modulation were evaluated retrospectively and divided into three study groups, each with an equal quantity of 50 patients (DSHP vs. single source 128 slices vs. single source 16 slices). By using a dedicated workstation, volumetric analyses of each of the scanned anatomic area were performed and correlated to the individual dose length product (DLP). The calculated result was defined as dose efficiency. Results: DLP was 203 mGycm (DSHP), vs. 269 mGycm (single source) vs. 273 mGycm (16 slice CT). The total patient volume was lowest in the dual source group with 18956.3 cm 3 (vs. 22481.2 cm 3 vs. 22133.8 cm 3 ). With regards to the DLP, the calculated dose efficiency of dual source CT was better than the 128 slice CT (p = 0.045) and the 16 slice CT (p < 0.01). Conclusions: DSHP CT has considerably better dose efficiency compared to 16 slice CT. Compared to 128 slice single source technique, the high-pitch mode does not cause any dose penalty when performing chest CT.

Objectives. We tried to define, on individual basis, minimal effective maintenance dose of intravenous immunoglobulins (IVIG) in 26 patients with chronic neurological conditions requiring long-term IVIG treatment.Methods. Clinical criteria were reviewed in individual cases (Phase 1) followed by titration phase (Phase 2, 12 months) and posttitration/follow-up phase (Phase 3, 3 months). Objective neurological examination and patient self-reports were used for clinical follow-up.Results. 69.2% of patients reported condition as stable, 26.9% as better, and 3.9% as mildly worse. Original mean monthly dose was 1 g/kg; over the period of 12 months we reduced dose of IVIG to mean dose 0.67 g/kg (range 0.3–2.5 g/kg,P<0.0001)which meant reduction by 36.4%. We identified 4 nonresponders and diagnosis in one case was reclassified to degenerative disease. In follow-up phase we reduced dose further to 0.60 g/kg. Cumulative monthly dose dropped from 2040 g to 1298 g and to 991 g, respectively. Financial expenses were reduced significantly (by −36.4% during titration phase and by −51.4% during follow-up phase) (comparing with baseline)(P<0.0001).Conclusion. Individual dose titration leads to significant maintenance IVIG dose reduction with preserved clinical efficacy. Maintenance dose below 1 g/kg (in our study around 0.7 g/kg) has acceptable risk/benefit ratio.

Purpose To identify patient characteristics that influence tacrolimus individual dose requirement in kidney transplant recipients. Methods Data on forty-four 12-h pharmacokinetic profiles from 29 patients and trough concentrations in 44 patients measured during the first 70 days after transplantation (1,546 tacrolimus whole blood concentrations) were analyzed. Population pharmacokinetic modeling was performed using NONMEM 7.2®. Results Standardization of tacrolimus whole blood concentrations to a hematocrit value of 45 % improved the model fit significantly (p 55 years that was 47 % higher than the male value at age

The improved use of collective dose following the 2007 ICRP recommendations is studied for nuclear and radiological emergency situations. To study the accumulation of low individual doses to the collective dose the collective dose is calculated as a function of the minimum individual dose for three cases including nuclear as well as radiological accidents. It is found that the use of collective dose in this way can have an added value in nuclear emergency preparedness and response in particular related to decisions on overall protective actions following an accident.

Objectives Nuclear medicine (NM) is a rapidly developing field. In Portugal, no occupational study has been conducted yet that characterizes the professional profile of NM technologists (NMTs). We investigated the clinical tasks performed by NMTs in Portugal, analysing their practices with regard to radiation protection matters and their compliance with established international guidelines for best practice. Methods A questionnaire targeted at NMTs was constructed and distributed among 105 NMTs working in Portugal (an estimated 88% of the NMT population in Portugal). Questions addressed the demographic profile, academic background and professional profile of NMTs, with emphasis on practices adopted in NM tasks and radiation protection. Results In all, 51.4% of the 105 NMTs responded. The majority (70.4%) of the NMTs studied were women, with an average age of 34.3 (± 10.4) years and 11.6 (± 10.6) years of professional experience. The reported NM tasks included radiopharmaceutical preparation (96.3%), PET (44.4%), intravenous administration (74.1%), administration with dose containers (97.7%) and administration with syringe shields (76.9%). The use of a protective lead apron was rare (2.7%). The average individual dose recorded was 3.8 (± 2.7%) mSv/year. Conclusion NMTs in Portugal are generally young women with specialized academic education, consistent with the developments in NM technology and education in Portugal since the past decade. The majority of NMT activities are focused on conventional NM. The estimated annual average individual dose is below the established legal limit. However, radiation protection practices related to staff protection are not harmonized, revealing key aspects to be considered in future education and training.

Time-activity patterns and the airborne pollutant concentrations encountered by children each day are an important determinant of individual exposure to airborne particles. This is demonstrated in this work by using hand-held devices to measure the real-time individual exposure of more than 100 children aged 8-11 years to particle number concentrations and average particle diameter, as well as alveolar and tracheobronchial deposited surface area concentration. A GPS-logger and activity diaries were also used to give explanation to the measurement results. Children were divided in three sample groups: two groups comprised of urban schools (school time from 8:30 am to 1:30 pm) with lunch and dinner at home, and the third group of a rural school with only dinner at home. The mean individual exposure to particle number concentration was found to differ between the three groups, ranging from 6.2 × 10(4)part.cm(-3) for children attending one urban school to 1.6 × 10(4)part.cm(-3) for the rural school. The corresponding daily alveolar deposited surface area dose varied from about 1.7 × 10(3)mm(2) for urban schools to 6.0 × 10(2)mm(2) for the rural school. For all of the children monitored, the lowest particle number concentrations are found during sleeping time and the highest were found during eating time. With regard to alveolar deposited surface area dose, a child's home was the major contributor (about 70%), with school contributing about 17% for urban schools and 27% for the rural school. An important contribution arises from the cooking/eating time spent at home, which accounted for approximately 20% of overall exposure, corresponding to more than 200 mm(2). These activities represent the highest dose received per time unit, with very high values also encountered by children with a fireplace at home, as well as those that spend considerable time stuck in traffic jams.

In 2014, a team of high school students and teachers measured individual exposure doses using D-Shuttle dosimeters. In total, 216 students and teachers participated in the project, with the cooperation of 12 high schools in Japan (six from Fukushima Prefecture), four from France, eight from Poland, and two from Belarus. The participants wore the dosimeters for 2 weeks and recorded their locations in diary charts. The distribution of annual exposure doses for each school and region, estimated from the measured results, overlapped. It was concluded that the external exposure of high school students in Fukushima Prefecture was not markedly higher compared with that of students from other regions.

A handheld portable dental intraoral x-ray system is available in the United States and elsewhere. The system is designed to minimize the user's radiation dose. It includes specially designed shielding of the x-ray tube housing and an integral radiation shield to minimize backscatter. Personnel radiation dose records were obtained from 18 dental facilities using both the handheld system and a wall mounted dental x-ray system, providing 661 individual dose measurements. Dental staff doses were also compared for the handheld and conventional systems using both film and digital imaging for the same facilities and staff members. The results indicate that the doses for the handheld systems are significantly less than for wall-mounted systems. The average monthly dose for the handheld systems was 0.28 μSv vs. 7.86 μSv (deep dose equivalent) for the wall-mounted systems, a difference that is statistically significant at the p = 0.01 level. Consequently, there should be no concern about the use of this handheld dental intraoral x-ray system. Additional shielding efforts, (e.g., wearing a lead apron) will not provide significant benefit nor reduce staff radiation dose.

We performed individual dose measurements, in terms of Hp(10) for the whole body, Hp(0,07) for the extremities (hands) and Hp(3) for the eyes, for medical personnel (technical staff, nurses and medical doctors) in three nuclear medicine departments. One conventional diagnostic scintigraphy department, where Tc-99m, I-131 and Sm-153 were applied, and two PET-CT departments where F-18 was applied in preparation and application procedures, were studied. A novel eye lens dosemeter was used, designed to evaluate Hp(3) directly. From our measurements we obtained ratios of Hp(3)/Hp(10) ranging between 0.7 and 1.1 indicating that in nuclear medicine procedures eye lens doses could probably be estimated from Hp(10) values and that exceeding the present annual dose limit to eye lens (150 mSv) is very unlikely. The relationship between different individual doses can indicate the quality of radiation protection in a nuclear medicine department.

Conventional diagnostic nuclear medicine applications have been continuously increasing in most nuclear medicine departments in Turkey, but to our knowledge no one has studied the doses to technologists who perform nuclear medicine procedures. Most nuclear medicine laboratories do not have separate control rooms for technologists, who are quite close to the patient during data acquisition. Technologists must therefore stay behind lead shields while performing their task if they are to reduce the radiation dose received. The aim of this study was to determine external radiation doses to technologists during nuclear medicine procedures with and without a lead shield. Another aim was to investigate the occupational annual external radiation doses to Turkish technologists. Methods: This study used a Geiger-Muller detector to measure dose rates to technologists at various distances from patients (0.25, 0.50, 1, and 2 m and behind a lead shield) and determined the average time spent by technologists at these distances. Deep-dose equivalents to technologists were obtained. The following conventional nuclear medicine procedures were considered: thyroid scintigraphy performed using 99mTc pertechnetate, whole-body bone scanning performed using 99mTc-methylene diphosphonate, myocardial perfusion scanning performed using 99mTc-methoxyisobutyl isonitrile, and 201Tl (thallous chloride) and renal scanning performed using 99mTc-dimercaptosuccinic acid. Results: The measured deep-dose equivalent to technologists per procedure was within the range of 0.13 ± 0.05 to 0.43 ± 0.17 μSv using a lead shield and 0.21 ± 0.07 to 1.01 ± 0.46 μSv without a lead shield. Also, the annual individual dose to a technologist performing only a particular scintigraphic procedure throughout a year was estimated. Conclusion: For a total of 95 clinical cases (71 patients), effective external radiation doses to technologists were found to be within the permissible levels. This study showed that a 2-mm lead shield markedly reduced the external dose to technologists. The doses to technologists varied significantly for different diagnostic applications. Consequently, the estimated annual dose to a technologist performing only a particular scintigraphic procedure is very different from one type of procedure to another. The results of this study should help in determining the rotation time of technologists in different procedures and differences in their individual techniques.

The activated accelerator cyclotron components and the radioisotope production may impact on the personnel radiation exposure of the workers during the routine maintenance and emergency repair procedures and any modification of the equipment. Since the adherence of the principle of ALARA (as low as reasonable achievable) constitutes a major objective of the cyclotron management, it has become imperative to investigate the radiation levels at the workplace and the probable health effects to the worker caused by radiation exposure. The data analysis in this study was based on the individual monitoring records during the period from 2007 to 2011. Monitoring of the workplace was also performed using gamma and neutron detectors to determine the dose rate in various predetermined spots. The results of occupational radiation exposures were analysed and compared with the values established in national standards and international recommendations. Important guidelines have been developed to reduce the individual dose.

This article discusses practical aspects of treatment of local hyperhidrosis with botulinum toxin type A (Dysport®). This method helps choose the individual dose of the administered drug taking into account the anatomical area and intensity of sweating, avoid psycho-emotional disorders, obtain good clinical results, reduce the risk of the onset and recurrence of chronic dermatoses considerably and improve the patients quality of life.

金沢大学医薬保健研究域保健学系, Recent linear accelerators can perform cone-beam computed tomography to correct setup errors immediately before dose delivery. We calculated the dose distribution with setup errors acquired from cone-beam computed tomography to determine a more realistic and individual effect of setup errors. The differences in dose distribution were analyzed. The setup errors of three patients who were irradiated in the neck, esophagus, and pelvic area were obtained retrospectively. We found that the maximum dose variances for the three cases were 19.9-35.9%. The maximum dose variance points were relatively far from the isocenter. The volume of the 10% dose difference had widths of 1.3-1.85 cm around the beam edges. The V95 and mean doses at the clinical target volume were mostly unchanged. Doses around the beam edges were more varied than those around the isocenter for every case. The dose on the spinal cord located near the beam edges varied by 5-10% compared with the dose of the radiotherapy plan in two of the cases. We demonstrated the individual dose distributions of the cases affected by daily setup errors for all fractions. © 2009 Japanese Society of Radiological Technology and Japan Society of Medical Physics.

An intercomparison exercise for personal dosimetry service providers within Pakistan was conducted by the Health Physics Division of the Pakistan Institute of Nuclear Science and Technology. Participation in the exercise was on voluntary basis. The exercise was carried out to harmonize individual dose monitoring techniques for high energy photons in terms of a new operational quantity, namely personal dose equivalent Hp(10), for personal dosimetry in accordance with the recommendations of the International Commission on Radiation Units and Measurements. Each laboratory submitted 25 dosimeters for participation in the intercomparison exercise. Protection level Co and Cs sources were used for irradiation of dosimeters on a water phantom according to International Atomic Energy Agency protocol at the Secondary Standard Dosimetry Laboratory. Hp(10) doses for five different dose levels were measured by the participating laboratories. The ratios of measured dose/true dose (Hm/Ht) remained in the range of 0.66 to 1.11 for the Co source and 0.84 to 1.17 for the Cs source. Performance of service providers' laboratories to measure Hp(10) doses was analyzed and evaluated in terms of trumpet curves plotted for photons at a 95% confidence level.

New drug developments for the treatment of topical lung diseases and systemic uptake can be achieved by using the inhalative route. High, specific and reproducible targeting of these new drugs to specific regions of the lung is desired. Radioaerosol techniques in combination with planar gamma camera imaging are described to achieve an individual dose assessment of inhaled aerosolized drugs and to adjust inhalation devices for individual patient use.

The therapy of obstipation must always be multicausal. This becomes especially difficult when a laxative abuse is present. When the patient cannot be offered successfully an effective and causal therapy, he/she quickly falls back on his/her "proven” but rather harmful remedies. With the change to enzymatically produced, partially hydrolyzed Guar gum powder it is possible, to achieve a return to a regular bowel movement, which is above the average. In contrast to other roughage, the active principle of partially hydrolyzed guar core flour is based on the water solubility, so that after finding an individual dose (in about 8-10 days), the regulative therapeutic effect develops.

This paper presents a systematic analysis of the inherent uncertainty in internal dose calculations for radiopharmaceuticals. A generic equation for internal dose is presented, and the uncertainty in each of the individual terms is analyzed, with the relative uncertainty of all terms compared. The combined uncertainties in most radiopharmaceutical dose estimates will be typically at least a factor of 2 and may be considerably greater. In therapy applications, if patient-individualized absorbed doses are calculated, with attention being paid to accurate data gathering and analysis and measurement of individual organ volumes, many of the model-based uncertainties can be removed, and the total uncertainty in an individual dose estimate can be reduced to a value of perhaps +/-10%-20%. Radiation dose estimates for different diagnostic radiopharmaceuticals should be appreciated and considered, but small differences in dose estimates between radiopharmaceuticals should not be given too much importance when one is choosing radiopharmaceuticals for general clinical use. Diagnostic accuracy, ease of use, image quality, patient comfort, and other similar factors should predominate in the evaluation, with radiation dose being another issue considered while balancing risks and benefits appropriately.

The requirements for biodosimetric techniques used at long times after exposure, i.e., 6 months to more than 50 years, are unique compared to the requirements for methods used for immediate dose estimation. In addition to the fundamental requirement that the assay measures a physical or biologic change that is proportional to the energy absorbed, the signal must be highly stable over time to enable reasonably precise determinations of the absorbed dose decades later. The primary uses of these biodosimetric methods have been to support long-term health risk (epidemiologic) studies or to support compensation (damage) claims. For these reasons, the methods must be capable of estimating individual doses, rather than group mean doses. Even when individual dose estimates can be obtained, inter-individual variability remains as one of the most difficult problems in using biodosimetry measurements to rigorously quantify individual exposures. Other important criteria for biodosimetry methods include obtaining samples with minimal invasiveness, low detection limits, and high precision. Cost and other practical limitations generally prohibit biodosimetry measurements on a large enough sample to replace analytical dose reconstruction in epidemiologic investigations. However, these measurements can be extremely valuable as a means to corroborate analytical or model-based dose estimates, to help reduce uncertainty in individual doses estimated by other methods and techniques, and to assess bias in dose reconstruction models. There has been extensive use of three biodosimetric techniques in irradiated populations: EPR (using tooth enamel), FISH (using blood lymphocytes), and GPA (also using blood); these methods have been supplemented with luminescent methods applied to building materials and artifacts. A large number of investigations have used biodosimetric methods many years after external and, to a lesser extent, internal exposure to reconstruct doses received from accidents, from occupational exposures, from environmental releases of radioactive materials, and from medical exposures. In most applications, the intent has been to either identify highly exposed persons or confirmed suspected exposures. Improvements in methodology, however, have led many investigators to attempt quantification of whole-body doses received, or in a few instances, to estimate organ doses. There will be a continued need for new and improved biodosimetric techniques not only to assist in future epidemiologic investigations but to help evaluate the long-term consequences following nuclear accidents or events of radiologic terrorism.

Purpose: scientific rationale approaches Express-diagnostics for athletes of taekwondo section by psychophysiological parameters. Material: Total surveyed 84 people, including 68 boys and 16 girls. Were defined backup capabilities, exercise tolerance and selection of adequate individual dose of loads in preparation for the international competition, participants - taekwondo athletes. Was attended by representatives of Ukraine, Russia and Lithuania. Age groups of participants: 6 - 16 years. Athletes have different levels and different schools of training. Results: evaluation of exercise tolerance and definition of an adequate level of motor mode in taekwondo athletes in terms of the difference of lability (DL) before and after training, revealed: high and very high nervous system (NS) lability. These figures correspond to high and very high tolerance to physical loads. The respondents who had difference of liability (DL), Цель: научное обоснование подходов Экспресс-диагностики для спортсменов секции тхэквондо по психофизиологическим параметрам. Материал: Всего обследовано 84 человека, из них 68 мальчиков и 16 девочек. Определялись резервные возможности, толерантность к физическим нагрузкам и подбор индивидуальных адекватных дозированных нагрузок в процессе подготовки к международным соревнованиям. Приняли участие представители стран Украины, России, Литвы. Возрастные группы участников: 6 - 16 лет. Спортсмены имели разный уровень и различные школы подготовки. Результаты: оценка толерантности к физическим нагрузкам и адекватного объема двигательного режима по показателям разности лабильности (РЛ) до и после тренировки выявили: высокую и очень высокую лабильность нервной системы (НС). Эти показатели соответствовали высокой и очень высокой толерантности к физическим нагрузкам. Показатель разности лабильности (РЛ) < 0 свидетельствовал о хорошей тренированности спортсменов. Высокий бал силы НС свидетельствовал о хороших резервных возможностях (выдерживать большую по величине и длительную нагрузку). У 78 % испытуемых нагрузка была подобрана адекватно (РЛ = 0). Менее чем у 20% респондентов отмечались средние резервные возможности. Они нуждались в индивидуальной коррекции дозированных нагрузок с целью повышения адаптационных возможностей. 10% респондентов имели низкую толерантность к физическим нагрузкам при средних значениях силы НС. Это свидетельствует о хороших резервных возможностях. Выявлена прямая зависимость у респондентов с высокими показателями по самочувствию, активности и настроению - низкие показатели тревожности, фрустрации, агрессии и ригидности. Выводы: предложенные оптимизированные подходы Экспресс-диагностики позволяют определить уровень физической выносливости, скорость адаптации спортсменов и адекватную реакцию на нагрузки., Мета : наукове обґрунтування підходів Експрес-діагностики для спортсменів секції тхеквондо за психофізіологічними параметрами. Матеріал : Всього обстежено 84 особи, з них 68 хлопчиків і 16 дівчаток. Визначалися резервні можливості, толерантність до фізичних навантажень і підбір індивідуальних адекватних дозованих навантажень в процесі підготовки до міжнародних змагань. Прийняли участь представники країн України, Росії, Литви. Вікові групи учасників: 6 - 16 років. Спортсмени мали різний рівень і різні школи підготовки. Результати : оцінка толерантності до фізичних навантажень і адекватного обсягу рухового режиму за показниками різниці лабільності (РЛ) до і після тренування виявили: високу і дуже високу лабільність нервової системи (НС). Ці показники відповідали високій і дуже високій толерантності до фізичних навантажень. Показник різниці лабільності (РЛ)

A population-based case-control study was conducted to estimate the radiation-related risk of thyroid cancer in persons who were exposed in childhood to (131)I from the Chernobyl accident of April 26, 1986 and to investigate the impact of uncertainties in individual dose estimates. Included were all 66 confirmed cases of primary thyroid cancer diagnosed from April 26, 1986 through September 1998 in residents of Bryansk Oblast, Russia, who were 0-19 years old at the time of the accident, along with two individually matched controls for each case. Thyroid radiation doses, estimated using a semi-empirical model based on environmental contamination data and individual characteristics, ranged from 0.00014 Gy to 2.73 Gy and had large uncertainties (median geometric standard deviation 2.2). The estimated excess relative risk (ERR) associated with radiation exposure, 48.7/Gy, was significantly greater than 0 (P = 0.00013) but had an extremely wide 95% confidence interval (4.8 to 1151/Gy). Adjusting for dose uncertainty nearly tripled the ERR to 138/Gy, although this was likely an overestimate due to limitations in the modeling of dose uncertainties. The radiation-related excess risk observed in this study is quite large, especially if the uncertainty of dose estimation is taken into account, but is not inconsistent with estimates previously reported for risk after (131)I exposure or acute irradiation from external sources.

The purpose of this study is to evaluate a new device providing real-time monitoring on radiation exposure during fluoroscopy procedures intending to reduce radiation in an interventional radiology setting.In one interventional suite, a new system providing a real-time radiation dose display and five individual wireless dosimeters were installed. The five dosimeters were worn by the attending, fellow, nurse, technician, and anesthesiologist for every procedure taking place in that suite. During the first 6-week interval the dose display was off (closed phase) and activated thereafter, for a 6-week learning phase (learning phase) and a 10-week open phase (open phase). During these phases, the staff dose and the individual dose for each procedure were recorded from the wireless dosimeter and correlated with the fluoroscopy time. Further subanalysis for dose exposure included diagnostic versus interventional as well as short (10 min) versus long (10 min) procedures.A total of 252 procedures were performed (n = 88 closed phase, n = 50 learning phase, n = 114 open phase). The overall mean staff dose per fluoroscopic minute was 42.79 versus 19.81 µSv/min (p0.05) comparing the closed and open phase. Thereby, anesthesiologists were the only individuals attaining a significant dose reduction during open phase 16.9 versus 8.86 µSv/min (p0.05). Furthermore, a significant reduction of total staff dose was observed for short 51 % and interventional procedures 45 % (p0.05, for both).A real-time qualitative display of radiation exposure may reduce team radiation dose. The process may take a few weeks during the learning phase but appears sustained, thereafter.

Data on occupational exposures from medical uses of radiation in China during 1986-2000 are presented. Individual dose monitoring results in the reports of monitoring centres in different provinces in China during 1986-2000 were collected as the basic data. These data were summarised and then analysed. From 1986 to 2000, in diagnostic radiology, nuclear medicine and radiotherapy, the annual collective effective doses varied within the range 122.4-206.6, 5.4-9.3 and 4.1-10.3 man Sv, respectively; the average annual effective dose in these categories varied within the range 1.5-2.2, 1.2-1.6 and 1.0-1.5 mSv, respectively. Almost all the average annual effective doses in medical uses of radiation were3 mSv in 1986-2000, and no monitored workers were found to have received an occupational exposure50 mSv in a single year or100 mSv in a 5-y period. After 1990, the protection status of medical radiation workers in China was sufficient.

A radiation cohort consisting of four panchayats and a control area consisting of two panchayats was identified in the high background radiation area of Karunagappally after measuring air kerma values of indoor and outdoor radiation levels in 75,052 houses in the area. Radioactivity in the soil was estimated from 181 samples collected from seven panchayats. Thoron-in-breath analysis was done in 87 subjects living in low, medium and high radiation level areas. Occupancy factor of 7711 subjects in different age groups was also estimated. Annual effective dose of individuals was calculated assuming the cosmic ray component of 0.227 and 0.252 mGy/year indoor and outdoor, respectively. Risk analysis will be attempted after measuring the individual dose of a sample population in the area.

In this issue of radiotherapy and oncology, two groups present their work on developing a predictive assay for the degree of radiation-induced normal tissue damage. Both groups have utilised in vitro tests using patients’ lymphocytes. The rational behind these studies is based on the fact that for curative radiotherapy, the tolerance of patients with the most severe normal tissue reactions determines the dose level for the patient group as a whole for a given tumour site and type. The ultimate aim is to develop a sufficiently robust predictive assay to enable individual dose adjustment, and thus improve the therapeutic ratio for the patient population as a whole [1,6,34–36,51]. Such studies can indeed provide information on the role of cell kill and/or DNA damage in determining morbidity, but are time consuming and unlikely to be used routinely in the clinic. The questions therefore arise as to the value of these studies for the future, and what the best way forward is.

The dose assessments of industrial radiographers who have been involved in radiation incidents in Iran during the years 2005-2009 are presented and discussed. All cases and events have been recognized by the regulatory body - National Radiation Protection Department of Iran as incidents based on the information declared by the Radiation Protection Officers. The registered dose values are in the range of 0 to 345 mSv.

Background: The paper presents the Nofer Institutes of Occupational Medicine in Łodź’s results of the assessment of individual dose equivalents Hp(0.07) of medical staff exposed to X-rays in Poland in 2012. In addition, the collected data was analysed in terms of types of medical units performing medical procedures and the categorization of personnel. Material and Methods: Do simetric service was provided for medical staff of interventional radiology departments occupationally exposed to ionizing radia tion in terms of individual dose equivalents Hp(0.07). In 2012, personal dosimetry Hp(0.07) determinations were performed by the Nofer Institute of Occupational Medicine in Łodź and covered 2044 employees from 174 health facilities. The determinations were performed using thermoluminescence dosimetry according to the procedure accredited by the Polish Centre for Accreditation (document number AB 327). The measurements were performed using ring-dosimeters in the periods of 1 or 2 months. Results: Mean annual individual dose equivalent Hp(0.07) in 2012 was equal to 3.3 mSv (annual limit for Hp(0.07) is 500 mSv). The average value of annual individual dose equivalent Hp(0.07) decreased comparing to the previous year. In 2012, no single case of exceeding the annual limit for Hp(0.07) was reported. Data stored in the file indicates that more than 96% of all of the an nual doses did not exceed the level of 10 mSv. Conclusions: The analysis of data on occupational exposure to ionizing radiation confirms a stable level of exposure and satisfactory radiological protection in interventional radiology facilities monitored by the Nofer Institute of Occupational Medicine in Łodź in Poland in 2012. Med Pr 2014;65(2):167–171

Antiarrhythmic agents are traditionally classified according to Vaughan Williams into four classes of action. Class I antiarrhythmic agents include most of the drugs traditionally thought of as antiarrhythmics, and have as a common action, blockade of the fast-inward sodium channel on myocardium. These agents have a very significant toxicity, and while they are being used less, therapeutic drug monitoring (TDM) does significantly increase the safety with which they can be administered. Class II agents are antisympathetic drugs, particularly the β-adrenoceptor blockers. These are generally safe agents which do not normally require TDM. Class III antiarrhythmic agents include sotalol and amiodarone. TDM can be useful in the case of amiodarone to monitor compliance and toxicity but is generally of little value for sotalol. Class IV antiarrhythmic drugs are the calcium channel blockers verapamil and diltiazem. These are normally monitored by haemodynamic effects, rather than using TDM. Other agents which do not fall neatly into the Vaughan Williams classification include digoxin and perhexiline. TDM is very useful for monitoring the administration (and particularly the safety) of both of these agents.

Individual neutron dosimetry represents one of the current difficulties in the field of radiological protection of workers. Since March 1999, the regulatory requirements in France for active (i.e. operational) dosimetry have been those of ICRP Publication 60, applicable from May 2000, necessitating the introduction of a new generation of neutron dosemeters. Over the last few years, the Institute for Nuclear Safety and Protection has been studying an individual electronic dosemeter for neutrons based on a semiconducting detector, capable of meeting the specifications laid down by a neutron dosimetry work group, including members from all the main players in the French nuclear industry. In 1998, the IPSN began transferring technology to the Saphymo company which, by the end of 2001, will be marketing Saphydose-n, the first individual dosemeter for neutrons which complies with IEC Standard 1323. This dosemeter is of compact design and can assess the individual dose equivalent H p (10) in mixed neutron and gamma radiation fields. It will be usable in any nuclear facility without prior knowledge of the average neutron spectrum or of the neutron-gamma ratio. It will be possible to connect the Saphydose-n dosemeter to any of the existing gamma deserter terminals to read the dose data and recharge the batteries.

Two examples of individual dose assessment of workers in special monitoring programs are presented, a uranium and an americium incorporation case. It is demonstrated that careful model modifications lead to better dose estimates but that in many cases an optimisation of parameters is not necessary to get a reliable assessment of the committed effective dose. In some cases the use of individual SEE values might be more sensitive with regard to the committed effective dose than very sophisticated modifications of biokinetic models.