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Abstract: The Institute of Electrical and Electronics Engineers establishes exposure reference levels ( ERL s) for electric fields ( E -fields) (0-300 GHz) and both induced ( I IND ) and contact currents ( I SC ) (<110 MHz) in its standard, IEEE Std C95.1™-2019 (IEEE C95.1). The "classical" scenarios addressed in IEEE C95.1 include a free-standing, grounded "reference" person ( I IND ) or an ungrounded reference person in manual contact with an adjacent grounded conductor ( I SC ), each exposed to a vertically oriented E -field driving the currents. The ERL s for current from 100 kHz to 110 MHz were established to limit heating in the finger (from touch), ankle ( I IND ), and wrist ( I SC from grasp contact), specifying the 6-min average specific absorption rate ( SAR , W kg -1 ) as the dosimetric reference limit ( DRL ); whole-body E -field ERL s are 30-min averages. The DRLs were established assuming a default "effective" local cross-section (9.5 cm 2 ) and consistent with a composite tissue conductivity of ~0.5 S m -1 . A previous publication described the misalignment of the ERL s for E -fields with the ERL s for I IND (which extends to I SC ) and also proposed a ramped E -field ERL from 100 kHz to 30 MHz. For the frequency range 100 kHz to 110 MHz, this paper proposes temperature increase ( ΔT ) in ankle and wrist as the preferred effect metric associated with I IND and I SC ; applying the E -field ERL s as surrogates for limits to these currents; and adopting the proposed ramp. The analysis of ΔT is based on the tissue mix in realistic anatomic depictions of ankle and wrist cross-sections; relevant tissue properties posted online; published tissue perfusion data; and anthropometric data on a large sample of male and female adults in the US military, allowing an estimate of effects over a range of body size. To evaluate ΔT versus frequency and time, the Penne bioheat equation was adapted with convective cooling from arterial blood as the lone cooling mechanism. The analysis revealed that I IND s and I SC s induced by ERL -level E -fields produce SAR s in excess of the local DRL s (in some cases far exceed). Calculations of time to ΔT of 5 °C, reflective of a potentially adverse (painful) response, resulted in worst-case times for effects in the ankle on the order of minutes but on the order of 10s of s in wrist. Thus, compliance with the E -field ERL , as assessed as a 30-min whole-body average is incompatible with the time course of potentially adverse effects in ankle and wrist from I IND and I SC , respectively. Further analysis of the relevant exposure/dose scenarios and consensus of stakeholders with a multi-disciplinary perspective will enable the development of a revised standard, practical from a compliance perspective and protective of all persons., (Copyright © 2024 Health Physics Society.)

Extremity radiation exposure in nuclear medicine is a growing concern because it may surpass the maximum permissible dose of 500 mSv. This study aimed to assess the occupational finger dose received by technologists during the preparation and administration of 18 F-FDG radiopharmaceuticals in positron emission tomography-computed tomography (PET-CT) whole-body scan procedures. Fifty scans were selected, with one procedure excluded due to a high administered activity. The mean administered activity per scan was 207.2 ± 41.8 MBq, with preparation and administration times averaging 1.44 ± 1.30 min and 0.46 ± 0.31 min, respectively. The technologist's mean total finger dose received during preparation and administration was 253.5 ± 153.3  µ Sv per procedure. A significant positive correlation was found between the administered activity and occupational dose, with patient's body mass index, preparation time, and administration time also contributing to dose variation. Based on 703 PET-CT procedures conducted in 2022, the estimated occupational finger dose for a technologist was 178.2 mSv annually. This value is well below the International Commission on Radiological Protection's maximum permissible dose of 500 mSv. The findings of this study have a significant impact on extremity dosimetry in nuclear medicine in Sri Lanka, as this is the first study of its kind., (© 2024 Society for Radiological Protection. Published on behalf of SRP by IOP Publishing Limited. All rights, including for text and data mining, AI training, and similar technologies, are reserved.)

Radiopharmacy staff members are subject to extremity radiation doses, particularly to the fingertips. Dosemeters, such as, thermoluminescent detectors (TLDs) are currently used for monitoring fingertip doses. This study aimed to use real-time dosemeters to monitor radiopharmacy extremity doses to identify specific procedural steps associated with higher fingertip doses and, subsequently, reduce dose through promotion of optimised radiation protection practises. Five radiopharmacy operators were monitored using an ED3 active extremity dosemeter with a detector attached to each tip of the index fingers. Dose rate and accumulated dose data were matched to the handled radioactivity data, of 99m Tc-labelled radiopharmaceuticals only, with the dose per activity ( μ Sv MBq -1 ) calculated for each step. Once baseline dose data was established, an educational session identified technique adjustments toward improved radiation protection. A subsequent monitored session was undertaken with the dose data compared to quantify changes in operator doses. Radiopharmacy steps which significantly contributed to extremity doses were identified. The average accumulated dose per activity across all procedural steps for the 99m Tc-labelled radiopharmaceuticals for all operators before the educational session was 0.042 ± 0.045 μ Sv MBq -1 and 0.042 ± 0.041 μ Sv MBq -1 ( n = 89) for non-dominant and dominant index fingertips, respectively, and 0.030 ± 0.044 μ Sv MBq -1 and 0.031 ± 0.032 μ Sv MBq -1 ( n = 97), respectively, afterwards. Overall, there was an average 40.7% reduction in the total extremity dose received after the educational session. Real-time electronic extremity dosemeters for monitoring radiopharmacy extremity dose presented as a useful tool for incorporation into radiation protection education and training, towards optimised radiopharmacy technique., (© 2024 Society for Radiological Protection. Published on behalf of SRP by IOP Publishing Limited. All rights, including for text and data mining, AI training, and similar technologies, are reserved.)

Liver radioembolization is an emerging treatment against liver primary and secondary tumours. The whole procedure of radioembolization involves different health care specialists with different expertise. During the fractionation and infusion phases, the personnel manipulates high activities of 90 Y. In our centre, the number of radioembolization treatments per year is increasing; the aim of this study is to monitor the dose to the operators and to estimate the radiological risk for the operators involved in the RE. At present, two medical devices are approved: Sir-Sphere® and Therasphere™, both loaded with 90 Y. The dosimeters used were TLDs placed over the fingertips, for a total of 4 dosimeters for each phase; the selected dose descriptor was Hp 0.07 . The study concerned 17 patients affected by malignant hepatic lesions, treated from September 2017 to March 2018. We performed 27 procedures: 10 fractionations (with Sir-Sphere®) and 17 infusions to the patients (10 with Sir-Spheres®, 7 with Theraspheres™). For fractionation phase, the average activity of each preparation was 3.34 GBq, the average value of Hp 0.07 was 0.50mSv. For infusion phase, the average activity was 1.51 GBq for Sir-Sphere® and 2.10 GBq for Theraspheres™, the average value of Hp 0.07 was 0.10mSv. No significant differences were found between senior (Hp 0.07  = 0.08mSv) and young operators (Hp 0.07  = 0.09mSv), respectively. Similarly, no significant differences were found between the right and left hand, with the same average value of Hp 0.07 (0.01mSv). In conclusion, the results are encouraging, since fingertips reported doses very low. The handling of 90 Y microspheres and the radioembolization procedure can be carried out under safe conditions., (Copyright © 2020 Sociedad Española de Medicina Nuclear e Imagen Molecular. Published by Elsevier España, S.L.U. All rights reserved.)

Low-dose radiation therapy (LDRT) has been successfully established for decades as an alternative analgesic treatment option for patients suffering from chronic degenerative and inflammatory diseases. In this study, 483 patients were undergoing LDRT for degenerative joint disease of the fingers and thumb at the University Hospital Erlangen between 2004 and 2019. Radiotherapy was applied according to the German guidelines for LDRT. Several impact factors on therapeutic success, such as the age and gender, the number of affected fingers, the single and cumulative dose, as well as the number of series, were investigated. In summary, 70% of the patients showed an improvement of their pain following LDRT. No significant impact was found for the factors age, gender, the number of series or the cumulative dosage. Patients with an involvement of the thumb showed a significantly worse outcome compared to patients with an isolated affection of the fingers. In this cohort, patients receiving a single dose of 0.5 Gy reported a significantly better outcome than patients receiving 1.0 Gy, strongly suggesting a reduction in the total dose. In summary, LDRT is a good alternative treatment option for patients suffering from degenerative and inflammatory joint disease of the fingers.

Aim:  The study examined the local dose distribution as well as the time course of skin exposure of hand and fingers from [ 68 Ga]Ga-DOTA-NOC synthesis using a self-shielded synthesis module., Methods:  A compact calibrated electronic dosimeter (ED) with a miniaturized probe was used for real-time measurements of skin dose equivalent H p  (0.07) (reference point: left and right index finger). A time resolved assessment of exposure during radiotracer production was performed. Additionally, thermoluminescence dosimeters (TLD) were used to determine local dose distribution for five different positions (e. g. fingertips). Cumulated H p  (0.07) estimated by ED was analysed and correlated with the measurements obtained by a TLD positioned close to the ED., Results:  The cumulative skin exposure from the production process measured by ED, was 74.7 ± 32.7 µSv/GBq and 40.1 ± 14.3 µSv/GBq for the right and left hand, respectively. The exposure recorded by the ED was in the average 19.4 % ± 40.0 % (median = 21.3 %) lower compared to the results from TLD. Highest exposure was recorded during synthesis (guided hand: 24.5 ± 12.2 µSv/GBq) and measuring of product yield including preparation of probes for quality control (guided hand: 36.1 ± 12.7 µSv/GBq). The highest local exposure was measured by a TLD close to the tip of the index finger of the guiding hand (range: 773-1257 µS/GBq)., Conclusion:  The chosen methodology using ED, proved to be a good concept for identifying procedure steps with an increased exposure level and to determine the time course of skin exposure and to identify procedure steps for further optimization of handling. Furthermore, miniaturized electronic dosimeters may be used for online surveillance of local exposure rates at hands and fingers., Competing Interests: The authors declare that they have no conflict of interest., (© Georg Thieme Verlag KG Stuttgart · New York.)

The purpose of this study was to evaluate the x-ray shielding ability of a novel tungsten-particle-containing rubber-based finger sack for use in interventional radiology. Shielding rates for the air kerma (mGy m) were measured using a semiconductor dosimeter with and without the finger sack and commercial lead gloves, at a 20 cm distance from the field of view. A C-arm digital angiography system was used with x-ray tube voltages of 60, 80, 100, and 120 kVp. In addition, the 70 μm dose equivalent to the operator's finger was measured using fluorescent glass dosimeters with and without the finger sack during interventional radiology examinations. The x-ray shielding rates for 60, 80, 100, and 120 kV x rays were 98.0 ± 0.03%, 94.8 ± 0.05%, 92.3 ± 0.12%, and 90.1 ± 0.03%, respectively, with the finger sack and 69.8 ± 0.39%, 61.0 ± 0.53%, 52.3 ± 0.52%, and 47.0 ± 0.69% with the lead gloves. The x-ray shielding rates for the fluoroscopy and cine mode with the finger sack were 91.3 ± 0.21% and 56.5 ± 0.58%, respectively, while with the lead gloves they were 96.5 ± 0.04% and 67.6 ± 0.33%. The 70 μm dose equivalent for the operator's finger exposure dose was reduced by approximately 39.4% using the finger sack. The finger shields were more user friendly, had excellent radiation shielding ability against x rays, and should reduce finger exposure in interventional radiology.

The human head and hand being in the near-field zone of a mobile phone antenna can drastically influence the antenna matching with free space. The goal of the presented research is to study this phenomenon on an inhomogeneous human model for different relative positions and distances of hand and fingers when using a mobile phone. The only safety criteria commonly used to estimate RF exposure impact on humans is the specific absorption rate (SAR). Its limits are determined by the Federal Communication Commission (FCC) in the USA and the International Commission on Non-Ionizing Radiation Protection (ICNIRP) in Europe. The maximal values of SAR for a mobile handset are determined for each model by the manufacturer. In this paper, it is shown that the peak values provided by the manufacturers and their understanding may need refinement. It is almost impossible to consider all parameters, such as the dependence of SAR on antenna communication matching, with a variety of shapes and forms and other details during physical measurements or numerical estimation. The premise for such assumptions is based on the analysis of S11 dependency on the exposure scenario and the fact that the Automatic Gain Control (AGC) increases power when the signal strength at the base station drops.

The purpose of this case study is to describe a dosimetric delivery of radiation to a superficial disease process involving the skin and bone of the distal finger. A 76-year-old male patient presented with a subungual squamous cell carcinoma (SCC) of the left distal index finger with bony involvement. The patient refused conventional surgical treatment but agreed to external beam radiation therapy (EBRT). There is a gap in the current literature describing how to successfully immobilize fingers and which EBRT modality is dosimetrically advantageous in treating them. The construction of a simple immobilization method with the patient in a reproducible position is described. The use of photons and electrons were compared ultimately showing photons to be dosimetrically advantageous. Long-term efficacy of the treatment was not evaluated because of patient noncompliance., (Copyright © 2017 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.)

Objective: When handling Y-labelled and Lu-labelled radiopharmaceuticals, skin exposure is mainly due to β-particles. This study aimed to investigate the equivalent dose saving of the staff when changing from an essentially manual radiolabelling procedure to an automatic dose dispenser (ADD)., Materials and Methods: The chemist and physician were asked to wear thermoluminescence dosimeters on their fingertips to evaluate the quantity of Hp(0.07) on the skin. Data collected were divided into two groups: before introducing ADD (no ADD) and after introducing ADD., Results: For the chemist, the mean values (95th percentile) of Hp(0.07) for no ADD and ADD are 0.030 (0.099) and 0.019 (0.076) mSv/GBq, respectively, for Y, and 0.022 (0.037) and 0.007 (0.023) mSv/GBq, respectively, for Lu. The reduction for ADD was significant (t-test with P<0.05) for both isotopes. The relative differences before and after ADD collected for every finger were treated using the Wilcoxon test, proving a significantly higher reduction in extremity dose to each fingertip for Lu than for Y (P<0.05). For the medical staff, the mean values of Hp(0.07) (95th percentile) for no ADD and ADD are 0.021 (0.0762) and 0.0143 (0.0565) mSv/GBq, respectively, for Y, and 0.0011 (0.00196) and 0.0009 (0.00263) mSv/GBq, respectively, for Lu. The t-test provided a P-value less than 0.05 for both isotopes, making the difference between ADD and no ADD significant., Conclusion: ADD positively affects the dose saving of the chemist in handling both isotopes. For the medical staff not directly involved with the introduction of the ADD system, the analysis shows a learning curve of the workers over a 5-year period. Specific devices and procedures allow staff skin dose to be limited.

As a result of some deviations in the installation of the X-ray inspection plant 'Extravolt-225/1600' two workers of an X-ray inspection laboratory were exposed to the radiation in a dose enough to cause an acute local radiolesions (LRs). The first patient was diagnosed with an acute LR of the hands of severe and extremely severe degree. The second patient was diagnosed with a mild LR of her right hand. The first patient received a surgical treatment followed by subcutaneous introduction of the autologous mesenchymal stem cells. The second patient received only conservative treatment. The complete epithelization of the traumatic surface was achieved. Modeling the incident with the following EPR analysis of the compact substance of the ablated bone structures made it possible to specify the spatial-temporal properties of the exposure., (© World Health Organisation 2016. All rights reserved. The World Health Organization has granted Oxford University Press permission for the reproduction of this article.)

Electron paramagnetic resonance (EPR) is a promising biodosimetric method, and fingernails are sensitive biomaterials to ionizing radiation. Therefore, kinetic energy released per unit mass (kerma) can be estimated by measuring the level of free radicals within fingernails, using EPR. However, to date this dosimetry has been deficient and insufficiently accurate. In the sampling processes and measurements, water plays a significant role. This paper discusses many effects of water on fingernail EPR dosimetry, including disturbance to EPR measurements and two different effects on the production of free radicals. Water that is unable to contact free radicals can promote the production of free radicals due to indirect ionizing effects. Therefore, varying water content within fingernails can lead to varying growth rates in the free radical concentration after irradiation-these two variables have a linear relationship, with a slope of 1.8143. Thus, EPR dosimetry needs to be adjusted according to the water content of the fingernails of an individual. When the free radicals are exposed to water, the eliminating effect will appear. Therefore, soaking fingernail pieces in water before irradiation, as many researchers have previously done, can cause estimation errors. In addition, nails need to be dehydrated before making accurately quantitative EPR measurements., (© The Author 2016. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.)

Wide and common applications of ionising radiation require continuous improvement of radiation safety and dosimetry methods. The thermoluminescent (TL) method is well known and very popular. Apart from its advantages, it also carries certain disadvantages. The erasure of the TL signal on detector readout and the resulting impossibility of post-readout dose reassessment is one of them. At the Institute of Nuclear Physics, Polish Academy of Sciences (IFJ PAN), a method for dose reassessment based on phototransferred thermoluminescence (PTTL) has been developed. This method has been applied for dose reassessment to MTS-N (LiF:Mg, Ti) detectors used in individual whole-body dosemeters and adjusted to an automatic reader used in routine measurements. The next step was to extend and adapt this method for extremity dosemeters. With the use of the PTTL method, it is possible to reassess relatively high doses measured on individual whole-body and extremity dosemeters collected from our customers after routine use. The influence of PTTL background has greater impact in extremity dosemeters where it is only one and thinner MTS-N detector compared with four MTS-N detectors in whole-body dosemeters. The minimum dose was determined as 5 mSv for extremity dosimetry. Below 5 mSv, the impact of PTTL background is comparable to the signal, and the estimated uncertainty of reassessed dose is at the level of reassessed dose., (© The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Stringent standards of hygiene must be applied in medical institutions, especially at operating blocks or during interventional radiology procedures. Medical equipment, including personal dosemeters that have to be worn by medical staff during such procedures, needs therefore to be sterilised. In this study, the effect of various sterilisation procedures has been tested on the dose response of extremity rings and of eye lens dosemeters in which thermoluminescent (TL) detectors (of types MTS-N and MCP-N, respectively) are used. The effects of medical sterilisation procedures were studied: by chemicals, by steam or by ultraviolet (UV), on the dose assessment by extremity rings and by eye lens dosemeters. Since it often happens that a dosemeter is accidentally machine-washed together with protective clothing, the effect of laundering on dose assessment by these dosemeters was also tested. The sterilisation by chemicals is mostly safe for TL detectors assuming that the dosemeters are waterproofed. Following sterilisation by water vapour, the response of these dosemeters diminished by some 30 %, irrespectively of the period of sterilisation; therefore, this method is not recommended. UV sterilisation can be applied to EYE-D™ eye lens dosemeters if their encapsulation is in black. The accidental dosemeter laundry in a washing machine has no impact on measured dose., (© The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

The requirements for determining extremity dosemeter performance have evolved over the past decade. In 2010, the Spanish Nuclear Safety Council (CSN) adopted a national protocol with performance requirements based on ISO 12794. Because of the lack of symmetry of ISO 4037-3 calibration phantoms, the isotropy test set up in the sagittal plane presented several challenges both for individual monitoring services and for calibration labs. This article proposes and validates a practical approach to reduce the number of irradiations. Results show that wrist and ring dosemeters in this study meet the ISO 12794 requirements for the isotropy test. However, additional studies would be needed to verify the newer IEC 62387 Standard., (© The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Staff manipulating radiopharmaceuticals in radiopharmacies and nuclear medicine departments can receive significant radiation doses to the tips of their fingers. However, dosemeters for monitoring the fingers are frequently attached to a ring worn at the base of the finger and the doses recorded are significantly lower. Therefore a correction factor is required to estimate the dose to the finger tip from that recorded by a ring dosemeter. A survey of practices in UK nuclear medicine departments has been undertaken via a questionnaire, results of studies in the literature reporting ratios of doses to the tip and base of the finger reviewed, and patterns of finger exposure studied using an electronic dosemeter. The survey indicates that UK staff use vial and syringe shields for the majority of manipulations. Ratios between doses to the tip and base of the index finger reported in the literature vary between 2 and 6. Higher ratios appear to be associated with poor protection practices including not using syringe shields and use of a finger to support a syringe needle. Staff are recommended to wear dosemeters on the palmar side of the index finger of each hand. Dosemeters worn at the finger tips are ideal, but doses to the tips can be estimated from ring dosemeters worn on the index fingers, and factors that can be used for this are proposed. For staff who always use vial and syringe shields and never touch the syringe needle or vial a factor of 3 is appropriate. For staff who mostly use syringe shields and may occasionally support a needle during an injection, a factor of 4 can be used, while for others a factor of 6 should be applied.

Purpose: Radioembolization of liver cancer with (90)Y-loaded microspheres is increasingly used but data regarding hospital staff exposure are scarce. We evaluated the radiation exposure of medical staff while preparing and injecting (90)Y-loaded glass and resin microspheres especially in view of the increasing use of these products., Methods: Exposure of the chest and finger of the radiopharmacist, nuclear medicine physician and interventional radiologist during preparation and injection of 78 glass microsphere preparations and 16 resin microsphere preparations was monitored. Electronic dosimeters were used to measure chest exposure and ring dosimeters were used to measure finger exposure., Results: Chest exposure was very low for both products used (<10 μSv from preparation and injection). In our experience, finger exposure was significantly lower than the annual limit of 500 mSv for both products. With glass microspheres, the mean finger exposure was 13.7 ± 5.2 μSv/GBq for the radiopharmacist, and initially 17.9 ± 5.4 μSv/GBq for the nuclear medicine physician reducing to 13.97 ± 7.9 μSv/GBq with increasing experience. With resin microspheres, finger exposure was more significant: mean finger exposure for the radiopharmacist was 295.1 ± 271.9 μSv/GBq but with a reduction with increasing experience to 97.5 ± 35.2 μSv/GBq for the six most recent dose preparations. For administration of resin microspheres, the greatest mean finger exposure for the nuclear medicine physician (the most exposed operator) was 235.5 ± 156 μSv/GBq., Conclusion: Medical staff performing (90)Y-loaded microsphere radioembolization procedures are exposed to safe levels of radiation. Exposure is lower than that from treatments using (131)I-lipiodol. The lowest finger exposure is from glass microspheres. With resin microspheres finger exposure is acceptable but could be optimized in accordance with the ALARA principle, and especially in view of the increasing use of radioembolization.

Aggressive digital papillary adenocarcinoma (ADPA) is a rare and often misdiagnosed malignant tumor of the sweat glands, most commonly encountered on the extremities. Due to the relatively high metastatic potential of the tumor, aggressive surgical treatment, including amputation, is generally recommended. We present a case of a 36-year-old male with an over 10-year history of a skin lesion on the right hand in the web space between the index and the middle finger. Histologically, the lesion revealed a malignant epithelioid neoplasm with features consistent with ADPA. The lesion was treated with 5-weeks preoperative radiation (total 5000 cGy) followed by surgical resection. There was no evidence of residual disease confirmed by pathological study of re-excision specimen as well as imaging studies. This is, to the best of knowledge, the first report of complete regression of an ADPA after radiotherapy., (© 2016 by the Association of Clinical Scientists, Inc.)

Background: The current routinely used methods of estimating the skin equivalent dose relies on the finger dosimetry which usually largely underestimates the real maximum exposure and thus appropriate correction factors have to be used., Methods: The group under the investigation consisted of 10 workers preparing and 5 workers administering radiopharmaceuticals labelled with 18F. The monitoring was carried out using 12 pairs of thermoluminiscent dosimeters (TLDs) placed on each hand of the worker. A total of 46 measurements were completed. The maximum exposure of the skin of hands, defined in terms of the quantity of the personal dose equivalent Hp(0.07), was related to the unit activity of radiopharmaceutical with which the worker came into the contact during the measurement., Results: The exposure of the hands of workers handling 18F-labelled radiopharmaceuticals showed significant inhomogeneity. Out of 15 workers, in 53 % of cases, the maximum skin exposure was observed on the tip of their index finger. It was estimated that in about 60 % of the cases (during the preparation and administration of radiopharmaceuticals), the exposure may exceed the 3/10 of the annual dose limit. Moreover, in 40 % of all cases, the exposure may even be higher than this dose limit. The established relevant correction factors reached the values up to 8 (as for preparations) and 13 (as for administrations)., Conclusions: The study resulted in the establishment of the appropriate correction factors and in the recommendations of procedures aimed at the further reduction of the exposure of extremities (Tab. 3, Fig. 2, Ref. 17).

Introduction: Handheld X-ray devices are now offered in dental practice. Handheld X-ray units challenge the concept of a restricted access to the "controlled area" as they are held by the operator. Although an integral lead shield is provided, the distance from the body is variable, dependent on how the device is held. The aim of this article was to investigate the level of operator dose when using a handheld X-ray device in various positions., Material and Methods: A NOMAD Pro™ Handheld X-ray system (Aribex Inc., Charlotte, NC) fitted with a remote control and mounted on a tripod was used in this study. A maxillofacial phantom ATOM(®) Max Dental and Diagnostic Phantom, model 711 HN (CIRS Inc., Norfolk, VA) was used to simulate the patient's head position. A mannequin was used to represent the operator. Pre-calibrated thermoluminescent dosemeters (TLDs) (Qados, Agar Scientific, Stansted, UK) were placed on the mannequin close to the eyes and at the level of thyroid, trunk, waist, hand (right finger + left palm) and feet, and three TLDs were used for background radiation. Three test scenarios were investigated; Position 1, close to operators' body and parallel to the ground; Position 2, away from the body with the arms fully extended (approximately 40 cm distance) and parallel to the ground; Position 3, perpendicular to the ground while the arms are partially extended. 30 exposures each of 1 s were performed in each test., Results: Background radiation was measured at 0.0110 mGy. The highest exposure after subtracting background radiation was recorded on the palm of the left hand (0.0310 mGy) at Position 3. The estimated dose to the operator was calculated based on an average workload of 100 intraoral radiographs weekly for a dental practitioner working 46 weeks a year., Conclusions: There is a negligible increase in operator exposure levels using handheld X-ray devices which remain well below the recommended levels of the Ionizing Radiation Regulations 1999. They could however represent an increase from what should be a nil exposure when using a wall-mounted machine. The position of the device relative to the operator has a significant effect on the overall operator's radiation exposure. The use of personal dosemeters is highly recommended to ensure a continuity of low radiation dose exposure. Furthermore, guidance, training and protocols on usage must be in place, strictly adhered to and regular audits are necessary to ensure compliance.

Objective: The purpose of this study was to evaluate the radiation exposure of vascular surgeons' eye lens and fingers during complex endovascular procedures in modern hybrid operating rooms., Methods: Prospective, nonrandomized multicenter study design. One hundred seventy-one consecutive patients (138 male; median age, 72.5 years [interquartile range, 65-77 years]) underwent an endovascular procedure in a hybrid operating room between March 2012 and July 2013 in two vascular centers. The dose-area product (DAP), fluoroscopy time, operating time, and amount of contrast dye were registered prospectively. For radiation dose recordings, single-use dosimeters were attached at eye level and to the ring finger of the hand next to the radiation field of the operator for each endovascular procedure. Dose recordings were evaluated by an independent institution. Before the study, precursory investigations were obtained to simulate the radiation dose to eye lens and fingers with an Alderson phantome (RSD, Long Beach, Calif)., Results: Interventions were classified into six treatment categories: endovascular repair of infrarenal abdominal aneurysm (n = 65), thoracic endovascular aortic repair (n = 32), branched endovascular aortic repair for thoracoabdominal aneurysms (n = 17), fenestrated endovascular aortic repair for complex abdominal aortic aneurysm, (n = 25), iliac branched device (n = 8), and peripheral interventions (n = 24). There was a significant correlation in DAP between both lens (P < .01; r = 0.55) and finger (P < .01; r = 0.56) doses. The estimated fluoroscopy time to reach a radiation threshold of 20 mSv/y was 1404.10 minutes (90% confidence limit, 1160, 1650 minutes). According to correlation of the lens dose with the DAP an estimated cumulative DAP of 932,000 mGy/m(2) (90% confidence limit, 822,000, 1,039,000) would be critical for a threshold of 20 mSv/y for the eyes., Conclusions: Radiation protection is a serious issue for vascular surgeons because most complex endovascular procedures are delivering measurable radiation to the eyes. With the correlation of the DAP obtained in standard endovascular procedures a critical threshold of 20 mSv/y to the eyes can be predicted and thus an estimate of a potential harmful exposure to the eyes can be obtained., (Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

New imaging technologies utilising X-rays and radiopharmaceuticals have developed rapidly. Clinical application of computed tomography (CT) has revolutionised medical imaging and plays an enormous role in medical care. Due to technical improvements, spatial, contrast and temporal resolutions have continuously improved. In spite of significant reduction of CT doses during recent years, CT is still a dominating source of radiation exposure to the population. Combinations with single photon emission computed tomography (SPECT) and positron emission tomography (PET) and especially the use of SPECT/CT and PET/CT, provide important additional information about physiology as well as cellular and molecular events. However, significant dose contributions from SPECT and PET occur, making PET/CT and SPECT/CT truly high dose procedures. More research should be done to find optimal activities of radiopharmaceuticals for various patient groups and investigations. The implementation of simple protocol adjustments, including individually based administration, encouraged hydration, forced diuresis and use of optimised voiding intervals, laxatives, etc., can reduce the radiation exposure to the patients. New data about staff doses to fingers, hands and eye lenses indicate that finger doses could be a problem, but not doses to the eye lenses and to the whole body., (© The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

We study the relationship between the blood flow and skin temperature variations under a cold pressor test (CPT). The simultaneous laser Doppler flowmetry (LDF) and skin temperature (ST) measurements were carried out for 8 healthy subjects on the skin surface of the distal phalanx of the second (LDF) and third (ST) fingers. The skin blood perfusion decreases stepwise about twice during contralateral CPT for all 8 subjects. The temperature of the finger pad decays monotonically during the test and dropped about 1°C in mean. The power spectral densities of LDF flow and ST variations are also affected by the CPT, but subjects under study demonstrate two different types of reaction. LDF pulsations at the frequency about 0.1 Hz, which corresponds to the myogenic mechanism of vascular tone regulation, decreases in 5 subjects and increases in other 3 subjects. However in all subjects the ST pulsations behave contradictory, namely, the changes in amplitude of blood perfusion and ST pulsations due to cold pressor test are strongly anticorrelated. We discuss possible mechanisms of vascular reaction that can cause the behavior observed.

There are few, but worrisome, data available on fingertip radiation exposure of medical personnel during radiosynovectomy (RSV). To reduce radiation exposure, we performed a dedicated application procedure. This report summarizes the acquired skin equivalent dose [Hp(0.07)] of the personnel involved in the preparation and administration of the three RSV β-emitters Y, Re and Er. Over a period of 3 years, 547 joints in 368 patients were treated with 52421 MBq of the aforementioned three radionuclides. The Hp(0.07) was recorded with thermoluminescence dosimeters worn on the dominant index fingertip and was analysed monthly. Eight staff members were exposed to an Hp(0.07) of 492 mSv. The cumulative dose was less than 10 μSv/MBq. The dose per person was 1.1 μSv/MBq in physicians and up to 4.5 μSv/MBq in technicians. The accumulated personal Hp(0.07) during RSV was far below the regulatory limit and published data.

A previous audit revealed a high frequency of adult fingers visualised on neonatal intensive care unit (NICU) chest radiographs-representing an example of inappropriate occupational radiation exposure. Radiation safety education was provided to staff and we hypothesised that the education would reduce the frequency of adult fingers visualised on NICU chest radiographs. Two cross-sectional samples taken before and after the administration of the education were compared. We examined fingers visualised directly in the beam, fingers in the direct beam but eliminated by technologists editing the image, and fingers under the cones of the portable x-ray machine. There was a 46.2% reduction in fingers directly in the beam, 50.0% reduction in fingers directly in the beam but cropped out, and 68.4% reduction in fingers in the coned area. There was a 57.1% overall reduction in adult fingers visualised, which was statistically significant (Z value - 7.48, P < 0.0001). This study supports radiation safety education in minimising inappropriate occupational radiation exposure.

Objective: The current procedure at our centre for partitioning multidose vials of fluorine-18-fluorodeoxyglucose (F-FDG) is based on a manual method. To reduce extremity dose while reducing contamination risk, maintaining product sterility and improving the accuracy of injected activity, we recently purchased a new semiautomated partitioning system (μDDS-A). This work reports on the operating characteristics of the system and its validation for clinical use in terms of dispensing accuracy and extremity dose reduction., Methods: A range of operators carried out 300 automated partitioning procedures by following a typical working-day setup. The accuracy of the activity resulting from system partitioning compared with true syringe activity was determined. We also determined the precision of system-determined activity when compared with user-requested activity. The cumulative finger dose for automated and manual partitioning techniques was measured at the fingertip using a digital dosimeter, recording the dose at different stages of the procedure., Results: The results of comparisons made between the final syringe activity measured by the system and the measurement of the true syringe activity independently of the system were within ±5% for 96.63% of syringes. Precision of the syringe activity provided by the system with respect to the user-requested activity was within ±10% for 96.96% of measurements. Average finger doses compared with a manual partitioning method showed a reduction of up to 80% when relying only on the system measurement of activity., Conclusion: The μDDS-A reproducibly partitions a vial of F-FDG and offers a significant reduction in extremity dose to the operator of up to 80% in comparison with a manual partition technique.

Purpose: Two patients with liver tumours were planned for a combined treatment, including surgery with preceding injections of β(-) radiation emitting (90)Y microspheres (SIRTEX(®)). The aim of this paper is to present a method of pre-surgical computer simulations of the absorbed dose rate on the surface of tumour tissue, combined with measurements of the actual absorbed dose rate on resected tissue, in order to estimate the absorbed dose to a surgeon's fingers during such surgery procedures., Methods and Materials: The dose rates from β(-) radiation on the surface of tumour tissue were simulated with the software VARSKIN(®) Mod 2. The activity concentrations in tumours were estimated, based on SPECT/CT distribution studies of (99m)Tc-MAA and confirmed by SPECT/CT bremsstrahlung studies of (90)Y microspheres. The activity distributions were considered as homogeneous within the tumour regions. The absorbed dose rates at different tumour tissue spots were calculated based on measurements with thermo-luminescent dosimeters (TLD) fastened on resected tissue., Results: The simulations showed a good agreement with the averaged absorbed dose rates based on TLD measurements performed on resected tissue, differing by 13% and 4% respectively. The absorbed dose rates at the measured maximum hotspots were twice as high as the average dose rates for both patients., Conclusion: The data is not sufficient in order to draw any general conclusions about dose rates on tumour tissue during similar surgeries, neither about the influence of dose rate heterogeneities nor about average dose rates. However, the agreement between simulations and measurements on these limited data indicate that this approach is a promising method for estimations of the radiation exposure to the surgeons' fingers during this kind of surgery procedure. More data from similar surgeries are necessary in order to validate the method.

A Joint Automatic Dispenser Equipment (JADE) has been designed and fabricated for automatic withdrawal and calibration of radiopharmaceutical materials. The thermoluminescent dosemeter procedures have shown a reduction in dose to the technician's hand with this novel dose dispenser system JADE when compared with the manual withdrawal of (99m)Tc. This system helps to increase the precision of calibration and to minimise the radiation dose to the hands and body of the workers. This paper describes the structure of this device, its function and user-friendliness, and its efficacy. The efficacy of this device was determined by measuring the radiation dose delivered to the hands of the nuclear medicine laboratory technician. The user-friendliness of JADE has been examined. The automatic withdrawal and calibration offered by this system reduces the dose to the technician's hand to a level below the maximum permissible dose stipulated by the international protocols. This research will serve as a backbone for future study about the safe use of ionising radiation in medicine.

Eppendorf tubes often are used in biomedical research labs and contain radioactive tracers. Although the associated direct contact finger doses are typically small, it is suggested (and in line with the principle of ALARA) to handle these tubes from the cap of the tube. When containing radioactive material, handling a tube near the bottom conical section would unnecessarily increase the skin dose to the fingers. This investigation modeled a 2.0-mL Eppendorf tube containing various individual beta emitting isotopes commonly used in a biomedical research environment (i.e., (14)C, (3)H, (131)I, (32)P, and (35)S) to determine the skin dose when directly handling the tube at the cap end and when handling it at the bottom conical section. The primary goal of this paper is to assess how significantly this dose is altered by handling geometry. The skin dose to a single finger was calculated with Monte Carlo simulations using MCNP5 and determined at a depth of 0.007 cm(2) in water averaged over 10 cm as described in 10CFR20. Results show that the dose rate may vary by as much as a factor of 700 depending on handling geometry.

Rhenium-188 (188Re) is of widespread interest for treating various diseases because of its attractive physical and chemical properties. The routine preparation of therapeutic doses of 188Re-labelled tracers can result in significant radiation exposure to the operator. We studied the impact of automating the preparation of 188Re-Lipiodol on the radiochemist's exposure, as well as the importance of the model of syringe shielding. To monitor radiation exposure continuously readable electronic personal dosimeters were used. Thermoluminescence dosimeters were fixed to the probable most exposed fingers of the radiochemist during preparation of the radiotracer and during the syringing. Dose rates were measured using a Babyline. Automation of the synthesis reduced personal dose equivalents from 2.60±4.35 to 1.61±1.20 µSv/GBq [Hp(10)] and from 38.37±55.28 to 21.84±16.14 µSv/GBq [Hp(0.07)]. Dose to the extremities was also reduced (-80% for the right hand; -58% for the left one). The Lemer-Pax PSWG syringe shield led to a slightly lower dose to the hands compared with the Medisystem (1.1±0.27 vs. 1.34±0.6 mSv/GBq for the right finger). Automation of the synthesis leads to a significant decrease in radiation exposure to the operator. The Lemer-Pax PSWG syringe shield provides better hand protection than the smaller Medisystem Mediclic.

The aim of this study is to measure radiation dose to the fingertips of occupationally exposed workers handling stranded iodine-125 seeds during prostate implants. The doses were measured by thermoluminescence dosimetry at the nail of the index finger of both hands in three hospitals in the Netherlands. In all hospitals, measurements were carried out during the preparation of stranded IBt seeds, type Intersource(®) 1251L. The fingertip doses per procedure (mean ± SD) to the fingertip for workers from the three hospitals were estimated to be 0.29 ± 0.15 mSv (n = 6), <0.03 ± <0.02 mSv (n = 8) and 0.31 ± 0.16 mSv (n=16), respectively. The lower doses found for the hospital 2 workers are presumably related to the heavier shielding and longer utensils used in that hospital. Even in the case of hundreds of implant procedures per year, dose to the fingertips for occupationally exposed workers preparing stranded seeds is expected to be well below the annual limit for extremities of 500 mSv.

A preliminary assessment of the occupational dose to the intervention radiologist received in fluoroscopy computerised tomography (CT) used to guide the collection of lung and bone biopsies is presented. The main aim of this work was to evaluate the capability of the reading system as well as of the available whole-body (WB) and extremity dosemeters used in routine monthly monitoring periods to measure per procedure dose values. The intervention radiologist was allocated 10 WB detectors (LiF: Mg, Ti, TLD-100) placed at chest and abdomen levels above and below the lead apron, and at both right and left arms, knees and feet. A special glove was developed with casings for the insertion of 11 extremity detectors (LiF:Mg, Cu, P, TLD-100H) for the identification of the most highly exposed fingers. The H(p)(10) dose values received above the lead apron (ranged 0.20-0.02 mSv) depend mainly on the duration of the examination and on the placement of physician relative to the beam, while values below the apron are relatively low. The left arm seems to receive a higher dose value. H(p)(0.07) values to the hand (ranged 36.30-0.06 mSv) show that the index, middle and ring fingers are the most highly exposed. In this study, the wrist dose was negligible compared with the finger dose. These results are preliminary and further studies are needed to better characterise the dose assessment in CT fluoroscopy.

The Work Package 4 of the ORAMED project, a collaborative project (2008-11) supported by the European Commission within its seventh Framework Programme, is concerned with the optimisation of the extremity dosimetry of medical staff in nuclear medicine. To evaluate the extremity doses and dose distributions across the hands of medical staff working in nuclear medicine departments, an extensive measurement programme has been started in 32 nuclear medicine departments in Europe. This was done using a standard protocol recording all relevant information for radiation exposure, i.e. radiation protection devices and tools. This study shows the preliminary results obtained for this measurement campaign. For diagnostic purposes, the two most-used radionuclides were considered: (99m)Tc and (18)F. For therapeutic treatments, Zevalin(®) and DOTATOC (both labelled with (90)Y) were chosen. Large variations of doses were observed across the hands depending on different parameters. Furthermore, this study highlights the importance of the positioning of the extremity dosemeter for a correct estimate of the maximum skin doses.

In August 2009, almost 1000 passive extremity dosemeters were irradiated at the Dosimetry Laboratory Seibersdorf as part of the EURADOS intercomparison IC2009. Forty-four European individual monitoring services participated, with a total of 59 dosimetry systems (46 finger ring, 4 finger tip and 9 wrist/ankle dosemeter systems). Additionally, finger-ring dosemeters from the Dosimetry Service Seibersdorf were irradiated in a non-competitive manner. Dosemeter irradiations on rod and pillar phantoms in four photon-radiation fields complying with the ISO standard 4037 were performed with personal dose equivalent values (H(p)(0.07)) ranging from 4 to 480 mSv. Traceability was established by using an air-kerma-calibrated monitor ionisation chamber together with the X-ray facility as well as a calibrated (137)Cs gamma radiation field with a collimated beam geometry. The ISO-tabulated conversion coefficients from air kerma free-in-air to H(p)(0.07) were applied, resulting in the main contribution to the expanded measurement uncertainties.

Purpose: Recent research by the authors on the effects of extremely low-frequency (ELF) magnetic field (MF) exposure on human heart rate (HR), heart rate variability (HRV), and skin blood perfusion found no cardiovascular effects of exposure to an 1,800-μT, 60-Hz MF. Research from our group using rats, however, has suggested a microcirculatory response to a 200-μT, 60-Hz MF exposure. The present pilot study investigated the effects of 1 h of exposure to a 200-μT, 60-Hz MF on the human circulation. Microcirculation (as skin blood perfusion) and HR were measured using laser Doppler flowmetry. Mean arterial pressure was monitored with a non-invasive blood pressure system., Methods: Ten volunteers were recruited to partake in a counterbalanced, single-blinded study consisting of two testing sessions (real and sham exposure) administered on separate days. Each session included four consecutive measurement periods separated by rest, allowing assessment of cumulative and residual MF effects., Results: A within-subjects analysis of variance did not reveal session by time period interactions for any of the parameters which would have been suggestive of a MF effect (p > 0.05). Perfusion, HR, and skin surface temperature decreased over the course of the experiment (p < 0.05)., Conclusions: The MF used in this experiment did not affect perfusion, HR, or mean arterial pressure. Decreasing perfusion and HR trends over time were similar to our previous results and appear to be associated with a combination of inactivity (resulting in decreasing body temperatures) and reduced physiological arousal.

The multi-spectral imaging technique has been used for distant mapping of in-vivo skin chromophores by analyzing spectral data at each reflected image pixel and constructing 2-D maps of the relative concentrations of oxy-/deoxy-haemoglobin and melanin. Instead of using a broad visible-NIR spectral range, this study focuses on narrowed spectral band 500-700 nm, speeding-up the signal processing procedure. Regression analysis confirmed that superposition of three Gaussians is optimal analytic approximation for the oxy-haemoglobin absorption tabular spectrum in this spectral band, while superposition of two Gaussians fits well for deoxy-haemoglobin absorption and exponential function - for melanin absorption. The proposed approach was clinically tested for three types of in-vivo skin provocations: ultraviolet irradiance, chemical reaction with vinegar essence and finger arterial occlusion. Spectral range 500-700 nm provided better sensitivity to oxy-haemoglobin changes and higher response stability to melanin than two reduced ranges 500-600 nm and 530-620 nm.

In this study, the nuclear medicine staff wore one finger dosimeter placed at the base of the index finger of the working hand. When a physician injected radioisotope drugs, the finger dose was 22.4 microSv, that for radiological technologists handling (99m)Tc was 29.6 microSv/day (consultation period 20 days), that for a physician injecting (18)F-FDG-PET drugs was 51.3 microSv (right finger 53.9 microSv, left finger 47.2 microSv), that for pharmacists' assay of FDG was 31.5 microSv, and that for radiological technologists positioning patients was 1.9 microSv. The largest value (94.1 microSv) was observed in physicians in the case of aspiration of a delivered drug. The finger dosimeter provides an effective solution for radiation protection procedures and follow-up. All the above staff members are on rotation and do not constantly handle radioactivity throughout the year.

Introduction: (90)Y-Zevalin labeling may cause severe finger radiation exposure, especially in high-dose protocols (HD-Zevalin), where up to 7.4 GBq could be injected. In this work, we optimized the labeling of HD-Zevalin with special regard to simplicity, speed, safety and radiation protection., Methods: Factors influencing labeling outcome (activity, specific activity, time, final volume, stability) were studied separately. The critical steps of a standard radiolabeling procedure were optimized to reduce finger exposure, developing an alternative labeling procedure and including a different (90)Y supplier. Finger doses were monitored by thermoluminescent dosimeters at each fingertip under anti-X gloves, considering both absolute values and values after normalization to 1.48 GBq., Results: Labeling of (90)Y-Zevalin was safe and reproducible up to 7.4 GBq with a simple and single-step procedure offering good stability for several hours. Radiolabeling specific activity was found critical, being kept at 740 MBq mg(-1). Radiochemical purity values >or=98% were routinely achieved. The alternative procedure allowed a sensible reduction of finger dose, due to both the different (90)Y vial and the handling. Finger exposure was reduced from 6.6+/-4.3 to 3.1+/-0.8 mSv/1.48 GBq in the case of the original (90)Y vial and from 1.5+/-0.9 to 0.3+/-0.1 mSv/1.48 GBq using a shielded (90)Y vial., Conclusions: HD-Zevalin can be prepared in a safe and reproducible way, giving high radiochemical purity values, good stability and low finger exposure. This study may improve the safety of nuclear medicine professionals involved in the preparation of Zevalin., (Copyright 2010 Elsevier Inc. All rights reserved.)

The objective of this study was to directly measure the radiation exposure to the orthopaedic surgeon and to measure dose points to the surgeon's fingers, thyroid gland, and forehead during intraoperative fluoroscopy in periacetabular osteotomy (PAO). In a series of 23 consecutive periacetabular osteotomy procedures, exposure monitoring was carried out using thermo luminescent dosimeters. The effective dose received by the operating surgeon was 0.008 mSv per operation which adds up to a yearly dose of 0.64 mSv from PAO. The median point equivalent dose (mSv) exposure under PAO was 0.009 for the forehead and thyroid gland, 0.045 for the right index finger, and 0.039 for the left index finger. The effective estimated yearly dose received by the operating surgeon was very low. Wearing a lead collar reduces radiation exposure to the thyroid gland while the lead gloves did not protect the surgeon's fingers.

Purpose: A recent publication from our centre revealed a disturbing finding of a significant incidence of adult fingers seen on the pediatric intensive care unit (PICU) chest radiographs. This is inappropriate occupational exposure to diagnostic radiation. We hypothesized that the incidence of adult fingers on PICU chest radiographs would decline after radiation safety educational seminars were given to the medical radiation technologists and PICU staff., Methods: The present study's objectives were addressed by using a pretest-posttest design. Two cross-sectional PICU chest radiograph samples, taken before and after the administration of radiation safety education for our medical radiation technologists and PICU staff, were compared by using a chi2 test., Results: There was a 61.2% and 76.9% reduction in extraneous adult fingers, directly exposed to the x-ray beam and those seen in the coned regions of the film, respectively, on PICU chest radiographs (66.7% reduction overall). This reduction was statistically significant (chi2 = 20.613, P < .001)., Conclusions: Limiting unnecessary occupational radiation exposure is a critical issue in radiology. There was a statistically and clinically significant association between radiation safety education and the decreased number of adult fingers seen on PICU chest radiographs. This study provides preliminary evidence in favour of the benefit of radiation safety seminars.

Background and Purpose: Only sparse reports have been made about radiation exposure of the treating physician during prostate seed implantation. Therefore, thermoluminescence dosimeter (TLD) measurements on the index fingers and the backs of both hands were conducted., Material and Methods: Stranded iodine-125 seeds with a mean apparent activity of 27.4 MBq per seed were used. During application, the treating physician manipulated the loaded needle with the index fingers, partially under fluoroscopic control. Four physicians with varying experience treated 24 patients. The radiation exposure was determined with TLD-100 chips attached to the index fingertips and the backs of hands. Radiation exposure was correlated with the physician's experience., Results: The average brachytherapy duration by the most experienced physician was 19.2 min (standard deviation sigma = 1.2 min; novices: 34.8 min [sigma = 10.2 min]). The mean activity was 1,703 MBq (sigma = 123 MBq), applied with 16.3 needles (sigma = 2.5 needles; novices: 1,469 MBq [sigma = 229 MBq]; 16.8 needles [sigma = 2.3 needles]). The exposure of the finger of the "active hand" and the back of the hand amounted to 1.31 mSv (sigma = 0.54 mSv) and 0.61 mSv (sigma = 0.23 mSv), respectively (novices: 2.07 mSv [sigma = 0.86 mSv] and 1.05 mSv [sigma = 0.53 mSv])., Conclusion: If no other radiation exposure needs to be considered, an experienced physician can perform about 400 applications per year without exceeding the limit of 500 mSv/year; for novices, the corresponding figure is about 200.

The purpose of this study was to directly measure, using thermoluminescent dosimeters, the radiation doses received by radiation team members performing (90)Y-ibritumomab tiuxetan administration. The occupational doses associated with two injection methods for patient administration - an automatic syringe driver and an injection box - were compared. The associated risks, namely cancer induction and hereditary effect, were also estimated from the results and compared with risk factors recommended by the International Commission on Radiological Protection publication 103. The results showed that the doses received by the index and thumb of the right hand and the index finger of the left hand of the radiation oncologist were significantly reduced by using the injection box method. The difference in the dose received by the medical physicist using the two methods was not statistically significant. It was observed that three pairs of latex gloves could further reduce the dose to the hands. The radiological risks of cancer induction and hereditary effect were negligible: of the order of 10(-6) and 10(-7) per (90)Y-ibritumomab tiuxetan administration, respectively, for both methods. However, the results of our study also showed that it would be possible in a busy centre for pregnant women to receive a dose of (90)Y-ibritumomab tiuxetan that exceeds the recommended annual dose limit for the surface of the abdomen.

This paper describes a high-performance transconductance amplifier specifically designed for electrotactile (electrocutaneous) stimulation. It enables voltages up to +/-600 V to be produced at the output that will allow the psychophysiological performance associated with stimulation of the fingertip using various stimulation waveforms to be studied more thoroughly. The design has a transconductance of up to 20 mA/V, an 8.8-Momega output resistance, and can provide output currents up to +/-20 mA. A complete schematic diagram is presented along with a discussion of theory of operation and safety issues as well as performance and derating plots from the implemented design.

Background: Smoking is reported to increase arterial stiffness. Indices obtained from the second derivative of digital volume pulse (SDDVP) waveform have been proposed to characterize vascular aging and arterial rigidity. PC6 (Neiguan) is a traditional acupoint in each forearm that has been shown to modify cardiovascular functioning., Objective: To investigate the acute effects of manual needling with PC6 on SDDVP indices in healthy chronic smoker and nonsmoker subjects., Subjects and Methods: Aging index (AI) was defined as (b - c - d - e)/a, B:A was calculated as the ratio of the absolute value for the height of the b wave (B) to that of the a wave (A), and D:A was calculated as the ratio of the absolute value for the height of the d wave (D) to that of the a wave (A). These indices derived of the wave components of SDDVP of healthy nonsmokers (n=40; 28.3+/-3.0 years old) vs. chronic smokers (n=30; 29.9+/-2.9 years old) were compared. The digital volume pulse (DVP) was obtained by measuring infrared light transmission through the finger. Of each subject, a DVP registration 20 minutes long was obtained. PC6 was stimulated unilaterally by manual needling for 5 minutes (1-6 minutes). SDDVP indices were compared in each subject in pre- vs. post-acupuncture periods (30 seconds vs. 18 minutes, respectively)., Results: At baseline, we found significant difference in B:A between nonsmokers and smokers. Comparing pre- vs. post-acupuncture periods, B:A and D:A did not show significant differences among nonsmokers, but B:A improved significantly in smokers and AI improved significantly in both nonsmokers and smokers., Conclusion: These findings suggest that manual needling with PC6 could revert some of the deleterious effects on vascular functioning produced by chronic cigarette smoking.

Objective: To examine the changes in slow (8-10Hz) and fast (10-12Hz) alpha bands of EEG in three groups of subjects submitted to different amounts of functional electrostimulation (FES). Our hypothesis is that different amounts of electrostimulation may cause different patterns of activation in the sensorimotor cortex. In particular, we expect to see an increase in alpha power due to habituation effects. We examine the two bands comprised by alpha rhythm (i.e., slow and fast alpha), since these two sub-rhythms are related to distinct aspects: general energy demands and specific motor aspects, respectively., Methods: The sample was composed of 27 students, both sexes, aging between 25 and 40 years old. The subjects were randomly distributed in three groups: control (n=9), G24 (n=9) and G36 (n=9). A FES equipment (Neuro Compact-2462) was used to stimulate the right index finger extension. Simultaneously, the electroencephalographic signal was acquired. We investigated the absolute power in slow and fast alpha bands in the sensorimotor cortex., Results: The G36 indicated a significant increasing in absolute power values in lower and higher alpha components, respectively, when compared with the control group. Particularly, in the following regions: pre-motor cortex and primary motor cortex., Discussion: FES seems to promote cortical adaptations that are similar to those observed when someone learns a procedural task. FES application in the G36 was more effective in promoting such neural changes. The lower and higher components of alpha rhythms behave differently in their topographical distribution during FES application. These results suggest a somatotopic organization in primary motor cortex which can be represented by the fast alpha component.

A syringe-type radiopharmaceutical being supplied by a manufacturer has a syringe shield and a plunger shield, whereas an in-hospital labeling radiopharmaceutical is administered by a disposable plastic syringe without the plunger shield. In cooperation with Nihon Medi-Physics Co. Ltd., we have produced a new experimental plunger shield for the disposable plastic syringe. In order to evaluate this shielding effect, we compared the leaked radiation doses of our plunger shield with those of the syringe-type radiopharmaceutical (Medi shield type). Our plunger shield has a lead plate of 21 mm in diameter and 3 mm thick. This shield is equipped with the plunger-end of a disposal plastic syringe. We sealed 99mTc solution into a plastic syringe (Terumo Co.) of 5 ml with our plunger shield and Medi shield type of 2 ml. We measured leaked radiation doses around syringes using fluorescent glass dosimeters (Dose Ace). The number of measure points was 18. The measured doses were converted to 70 microm dose equivalent at 740 MBq of radioactivity. The results of our plunger shield and the Medi shield type were as follows: 4-13 microSv/h and 3-14 microSv/h at shielding areas, 3-545 microSv/h and 6-97 microSv/h at non-shielding areas, 42-116 microSv/h and 88-165 microSv/h in the vicinity of the syringe shield, and 1071 microSv/h and 1243 microSv/h at the front of the needle. For dose rates of shielding areas around the syringe, the shielding effects were approximately the same as those of the Medi shield type. In conclusion, our plunger shield may be useful for reducing finger exposure during the injection of an in-hospital labeled radiopharmaceutical.