Occupational radiation exposure assessment during the management of [68Ga]Ga-DOTA-TOC

Background: Since it was first approved in Europe in 2016, the gallium-68 (68Ga) radiopharmaceutical [68Ga]Ga-DOTA-TOC has been widely used for imaging of somatostatin receptor (SSTR) positive tumours using positron emission tomography-computed tomography (PET/CT). Significant patient benefits have been reported, so its use is rapidly increasing. However, few studies have been published regarding occupational doses to nuclear medicine personnel handling this radiopharmaceutical, despite its manual usage at low distances from the skin and the beta-emission decay scheme, which may result in an increased absorbed dose to their hands. In this context, this study aims to analyse the occupational exposure during the administration of [68Ga]Ga-DOTA-TOC for PET/CT imaging. For this purpose, extremity, eye lens and whole-body dosimetry in terms of Hp(0.07), Hp(3) and Hp(10), respectively, was conducted on six workers with both thermoluminescent dosimeters, and personal electronic dosimeters. Results: The non-dominant hand is more exposed to radiation than the dominant hand, with the thumb and the index fingertip being the most exposed sites on this hand. Qualitative analysis showed that when no shielding is used during injection, doses increase significantly more in the dominant than in the non-dominant hand, so the use of shielding is strongly recommended. While wrist dosimeters may significantly underestimate doses to the hands, placing a ring dosimeter at the base of the ring or middle finger of the non-dominant hand may give a valuable estimation of maximum doses to the hands if at least a correction factor of 5 is applied. Personal equivalent doses for the eyes did not result in measurable values (i.e., above the lowest detection limit) for almost all workers. The extrapolated annual dose estimations showed that there is compliance with the annual dose limits during management of [68Ga]Ga-DOTA-TOC for diagnostics with PET in the hospital included in this study. Conclusions: Imaging with [68Ga]Ga-DOTA-TOC is a safe process for the workers performing the administration of the radiopharmaceutical, including intravenous injection to the patient and the pre- and post-activity control, as it is highly unlikely that annual dose limits will be exceeded if good working practices and shielding are used.Euratom research and training programme 2019?2020 under Grant Agree? ment N? 945196 (SINFONIA Projec

Dosimetry during percutaneous coronary interventions of chronic total occlusions

Percutaneous coronary interventions (PCI) of coronary chronic total occlusions (CTO) increase the risk of high radiation exposure for both the patient and the cardiologist. This study evaluated the maximum dose to the patients' skin (MSD) and the exposure of the cardiologists during CTO-PCI. Moreover, the efficiency of radioprotective drapes to reduce cardiologist exposure was assessed. Patient dose was measured during 31 procedures; dose to the cardiologist's extremities were measured during 65 procedures, among which 31 were performed with radioprotective drapes. The MSD was high (median: 1254 mGy; max: 6528 mGy), and higher than 2 Gy for 33% of the patients. The dose to the cardiologists' extremities per procedure was also of concern (median: 25-465 mu Sv), particularly to the left eye (median: 68 mu Sv; max: 187 mu Sv). Radioprotective drapes reduced the exposure to physician's upper limbs and eyes; especially to the left side (from -28 to -49%)

Performance testing of dosimeters used in interventional radiology: Results from the VERIDIC project

Interventional procedures in radiology and cardiology are associated with high dose to the patient. Accurate dosimetry is essential and calibration of the equipment is a means to provide the necessary accuracy of dose assessment. The objective of this work is to investigate the performance of dosimeters used in interventional procedures in different standard and non-standard X-ray radiation qualities, and to investigate potential uncertainties related to dose measurements, thus improving accuracy of patient dosimetry in interventional procedures. Four new reference radiation qualities dedicated to interventional cardiology applications have been established, allowing calibration of dosimeters used in clinical conditions with appropriate traceability to primary standards. Testing of solid-state semiconductor detectors and thermoluminescent dosimeter properties, e.g. influence of photon energy, angle of incidence and dose rate, was performed in the standard and non-standard radiation qualities. Both dosimeter types showed good performance in the non-standard beams during all performance tests. Solid-state dosimeters displayed weak dependence on energy, angle of incidence and dose rate, in the range defined by the manufacturer and requirements of the international standard. Thermoluminescent dosimeters displayed excellent linearity and angular dependence. The influence of energy dependence on measurement uncertainty can be reduced if appropriate radiation quality is selected for calibration. © 2021 Elsevier Lt

Efficacy of MAVIG X-Ray Protective Drapes in Reducing Operator Radiation Dose in the Cardiac Catheterization Laboratory A Randomized Controlled Trial

BACKGROUND: Interventional cardiologists are occupationally exposed to high doses of ionizing radiation. The MAVIG X-ray protective drape (MXPD) is a commercially available light weight, lead-free shield placed over the pelvic area of patients to minimize operator radiation dose. The aim of this study was to examine the efficacy of the MXPD during routine cardiac catheterization, including percutaneous coronary interventions. METHODS: We performed a prospective, randomized controlled study comparing operator radiation dose during cardiac catheterization and percutaneous coronary intervention (n=632) with or without pelvic MXPD. We measured operator radiation dose at 4 sites: left eye, chest, left ring finger, and right ring finger. The primary outcomes were the difference in first operator radiation dose (µSv) and relative dose of the first operator (radiation dose normalized for dose area product) at the level of the chest in the 2 groups. RESULTS: The use of the MXPD was associated with a 50% reduction in operator radiation dose (median dose 30.5 [interquartile range, 23.0-39.7] µSv in no drape group versus 15.3 [interquartile range, 11.1-20.0] µSv in the drape group; P<0.001) and a 57% reduction in relative operator dose (P<0.001). The largest absolute reduction in dose was observed at the left finger (median left finger dose for the no drape group was 104.9 [75.7-137.4] µSv versus 41.9 [32.6-70.6] µSv in the drape group; P<0.001). CONCLUSIONS: The pelvic MXPD significantly reduces first operator radiation dose during routine cardiac catheterization and percutaneous coronary intervention. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT04285944.status: publishe

DOSIS & DOSIS 3D: long-term dose monitoring onboard the Columbus Laboratory of the International Space Station (ISS)

The radiation environment encountered in space differs in nature from that on Earth, consisting mostly of highly energetic ions from protons up to iron, resulting in radiation levels far exceeding the ones present on Earth for occupational radiation workers. Since the beginning of the space era, the radiation exposure during space missions has been monitored with various active and passive radiation instruments. Also onboard the International Space Station (ISS), a number of area monitoring devices provide data related to the spatial and temporal variation of the radiation field in and outside the ISS. The aim of the DOSIS (2009–2011) and the DOSIS 3D (2012–ongoing) experiments was and is to measure the radiation environment within the European Columbus Laboratory of the ISS. These measurements are, on the one hand, performed with passive radiation detectors mounted at 11 locations within Columbus for the determination of the spatial distribution of the radiation field parameters and, on the other, with two active radiation detectors mounted at a fixed position inside Columbus for the determination of the temporal variation of the radiation field parameters. Data measured with passive radiation detectors showed that the absorbed dose values inside the Columbus Laboratory follow a pattern, based on the local shielding configuration of the radiation detectors, with minimum dose values observed in the year 2010 of 195–270 lGy/day and maximum values observed in the year 2012 with values ranging from 260 to 360 lGy/day. The absorbed dose is modulated by (a) the variation in solar activity and (b) the changes in ISS altitude

Secondary neutron doses in a proton therapy centre

The formation of secondary high-energy neutrons in proton therapy can be a concern for radiation protection of staff. In this joint intercomparative study (CERN, SCK•CEN and IBA/IRISIB/ULB), secondary neutron doses were assessed with different detectors in several positions in the Proton Therapy Centre, Essen (Germany). The ambient dose equivalent H*(10) was assessed with Berthold LB 6411, WENDI-2, tissue-equivalent proportional counter (TEPC) and Bonner spheres (BS). The personal dose equivalent Hp(10) was measured with two types of active detectors and with bubble detectors. Using spectral and basic angular information, the reference Hp(10) was estimated. Results concerning staffexposure show H*(10) doses between 0.5 and 1 nSv/monitoring unit in a technical room. The LB 6411 showed an underestimation of H*(10), while WENDI-2 and TEPC showed good agreement with the BS data. A large overestimation for Hp(10) was observed for the active personal dosemeters, while the bubble detectors showed only a slight overestimation.SCOPUS: ar.jinfo:eu-repo/semantics/publishe