Staff Doses Research Articles

Evaluation of Environmental Radiation Exposure and Algorithms for Determining the Occupational Effective Dose During 99mTc-MDP Bone Scintigraphy: A Comprehensive Analysis

This study evaluated the occupational exposure of radiopharmacists, nurses, radiological technologists, and radiological technologist assistants involved in 99mTc-MDP bone scintigraphy procedures. Actual occupational effective doses for individual staff needed ascertaining. An environmental radiation exposure audit revealed all nuclear medicine areas were compliant with ICRP and IAEA guidelines. To ascertain individual doses, they were recorded by OSL badges. The highest exposure was to the radiopharmacists, Hp(0.07) 2.19 µSv during radiolabeling. The nurse administering 99mTc-MDP recorded a dose of 0.27 µSv at Hp(0.07), 26.01% of the total occupational effective dose. The radiological technologist and assistant receive 73.05% of the total effective dose. However, the highest effective dose was received by the technologist assistant positioning patients for SPECT/CT scans, with an effective dose of 32.03 µSv. Single and double dosimetry effective dose estimate algorithms were evaluated, resulting in the double dosimetry being more accurate. The Padovani et al. algorithm was found to most closely align with 99mTc-MDP actual effective dose values (p > 0.05), thereby validating the measurement methods used in this study. The research offers benchmark environmental exposure and effective doses applicable in audits and the continuous effort to enhance radiation safety for personnel during 99mTc-MDP bone scintigraphy.

Automated Injectors versus Manual Administration: A Comparative Analysis of Radiation Exposure Reduction in 18F-FDG Delivery

Abstract Background Despite the presence of safety protocols, the manual manipulation of radiopharmaceuticals continues to pose a significant occupational radiation risk. Health care professionals in nuclear medicine are at risk of radiation exposure, particularly to their hands and eyes. Despite existing protective measures, manual handling of radiopharmaceuticals remains a significant source of occupational radiation. Objective This study evaluates the effectiveness of automated injectors in reducing radiation exposure among health care workers during fluorine-18 fluorodeoxyglucose (18F-FDG) administrations, compared with traditional manual injection methods. Methods We assessed radiation exposure levels associated with manual versus automated 18F-FDG injection techniques using specialized dosimeters. Measurements focused on whole-body, extremity, and eye-lens radiation doses to evaluate the potential benefits of automation in minimizing exposure. Results Findings reveal that automated injectors significantly reduce radiation exposure, with decreases of 97.97 and 98.96% in left- and right-hand extremity doses, respectively, 43.24% in eye-lens dose, and 91.66% in whole-body dose compared with manual methods. Conclusion Automated injection systems offer considerable advantages in reducing health care worker radiation exposure in nuclear medicine. The substantial reduction in staff doses underscores the necessity of transitioning to such technology to promote safer clinical environments. This study highlights the critical role of automation in enhancing occupational safety standards within diagnostic radiology settings.

Assessment of occupational radiation exposure during a specific endoscopic retrograde cholangiopancreatography procedure.

The aim of this study was to evaluate the occupational radiation exposure of staff during endoscopic retrograde cholangiopancreatography (ERCP), with a focus on individuals closest to the radiation source, and to identify potential increases in exposure to hands and eye lenses. Patient radiation exposure during ERCP was also assessed. Staff organ doses were monitored using a Philips Allura Xper FD 20 fluoroscopy system, during 24 ERCP procedures for a period of 7months. Staff doses were measured using thermoluminescence dosemeters and electronic personal dosemeters, and patient effective doses were simulated and calculated. Physicians' annual organ doses ranged from 0.2 to 1.6mSv for shoulders, 0.1 to 0.4mSv for eye lenses, and 0.3 to 1.6mSv for fingers. The annual organ dose of the nursing staff ranged from 0.08 to 2.4mSv for shoulders, 0.02 to 2.3mSv for eye lenses, and 1.2 to 5.3mSv for fingers. The effective dose to patients ranged from 0.009 to 0.46mSv. Staff doses were within safe limits, but patient doses were high, emphasizing the need for improved radiation protection.

Advancements in Cardiac Catheterization Safety: Novel Radiation Protection Approaches Redefining Occupational Health.

Radiation exposure poses a substantial occupational risk for healthcare professionals in the catheterization laboratory (cath lab). The escalating complexity and frequency of interventional procedures, such as cardiac catheterizations and percutaneous coronary interventions, underscore the need for innovative strategies to mitigate radiation exposure. While traditional measures like lead aprons, thyroid collars, and goggles have been pivotal in reducing radiation exposure, they have limitations, especially during prolonged and intricate procedures. Consequently, there is a growing demand for advanced radiation protection methods that prioritize safety without compromising procedural efficacy. Recent strides in radiation protection technology have given rise to novel shielding devices and zero-radiation approaches tailored for cath lab use. The novel shields leverage innovative materials and designs to achieve superior attenuation of both scattered and direct radiation. Their ergonomic and adjustable features also ensure optimal shielding coverage without impeding the operator's skill or workflow. Multiple studies have validated the effectiveness of these advanced radiation protection methods in diminishing occupational radiation exposure in the cath lab. Initial findings suggest a significant reduction in doses for operators and staff, potentially lowering the risk of radiation-induced health complications over the long term. This article provides a comprehensive review of the current landscape of radiation protection shields in the cath lab, emphasizing the efficacy and potential of these cuttingedge shielding technologies.

Radioactivity concentration of 14C in the air of 14C urea breath test rooms and the resulting internal dose to medical staff

ObjectiveTo monitor the radioactivity concentration of 14C in the air of rooms used to perform 14C urea breath tests, and evaluate the contamination status of 14C released during such tests, and assess the occupational health risk to medical staff working in such areas. Methods14CO2 in air was absorbed from the air and turned into calcium carbonate through a chemical reaction. Then, calcium carbonate was prepared into a suspension in a low-potassium glass vial. The sample was analyzed using a low-background liquid scintillation counter. ResultsThe radioactivity concentrations of 14C in air of the breath-test rooms in hospitals and physical examination institutions range from 1.35 to 18.41 Bq/m3. The annual committed dose for medical staff was estimated to be between 2.01 × 10−2 and 2.74 × 10−1 μSv. ConclusionsOur results reveal a significant increase of 14C radioactivity concentration in the air of breath-test rooms, but the resulting committed dose is much lower than the limits prescribed by the International Commission on Radiological Protection (ICRP). However, the potential risk of long-term exposure to low-dose radiation should be paid more attention.

Conservative assessment of external radiation dose for staff in the event of radionuclide flaw detection

The article proposes a new approach to assessing the effective doses of flaw detectorists performing flaw detection using portable radionuclide flaw detectors (gamma flaw detectors). The existing approach to assessing effective doses, based on the use of one individual dosimeter placed on work clothes in the chest area, is inadequate for the actual working conditions of exposure of flaw detectorists. Gamma flaw detectors contain a closed man-made source of ionizing radiation in their head, therefore, even in the non-working position, such flaw detectors pose a radiation hazard. When transporting and preparing gamma flaw detectors for work, the flaw detector operator is in close proximity to the radiation source. The irradiation geometry changing during the technological cycle when working with portable gamma flaw detectors at certain stages creates a sharply uneven irradiation of the flaw detectorist’s body. Therefore, after assessing the stages of the technological cycle, an option was proposed for a more conservative assessment of effective doses – to change the location of the individual dosimeter on the working clothes of the flaw detectorist, moving the individual dosimeter to the abdominal area. An anonymous study was carried out with the participation of 15 flaw detectorists; three individual dosimeters were displayed on their working clothes: two of them were experimental and were placed in the chest and abdomen; the third (a control dosimeter) was exposed for the quarter on the chest as part of constant individual dosimetric monitoring. In controlled anonymous measurements, the average effective dose, estimated from the readings of dosimeters exposed in the chest area, was equal to 0,95 mSv (median – 0,92 mSv, maximum value – 1,27 mSv). These values were compared with values obtained using dosimeters that were exposed to the abdomen, and the differences were significant (the average effective dose was 1,24 mSv (median – 1,22 mSv, maximum value – 1,78 mSv).

The estimation of the occupational radiation dose for medical staff in Thailand by using retrospective annual dosimetry data

The estimation of the occupational radiation dose for medical staff in Thailand by using retrospective annual dosimetry data

Medical staff dose estimation during pediatric cardiac interventional procedures.

The purpose of this study is to evaluate the occupational doses (eye lens, extremities and whole body) in paediatric cardiac interventional and diagnostic catheterization procedures performed in a paediatric reference hospital located in Recife, Pernambuco. For eye lens dosimetry, the results show that the left eye receives a higher dose than the right eye, and there is a small difference between the doses received during diagnostic (D) and therapeutic (T) procedures. The extrapolated annual values for the most exposed eye are close to the annual limit. For doses to the hands, it was observed that in a significant number of procedures (37 out of 45 therapeutic procedures, or 82%) at least one hand of the physician was exposed to the primary beam. During diagnostic procedures, the physician's hand was in the radiation field in 11 of the 17 catheterization procedures (65%). This resulted in a 10-fold increase in dose to the hands. The results underscore the need for optimization of radiation safety and continued efforts to engage staff in a radiation safety culture.

Developing methodology to evaluate eye lens dose for medical staff

Due to epidemiological evidence on the increasing incidence of cataracts in interventional doctors, The International Commission on Radiological Protection (ICRP) recommended decreasing the eye lens dose limit from 150 mSv/year to 20 mSv/year. Thus, The current status of dose assessment for healthcare workers shows that it requires more precise measurements of eye lens dose. we have researched Investigating dosimetric characteristics of OSLD nanoDot and Inlight type, using a multi–filter technique to determine the average air kerma of the incident beam and other essential dosimetric factors such as the relative energy responses and conversion coefficients from the air kerma to personal dose equivalent operational quantities Hp(d). Based on it developed the methodologies to evaluate eye lens dose for medical staff, especially high-risk subjects such as interventional doctors. Results show that 3 methods to evaluate eye lens dose have been deployed in the cardiovascular intervention department: directly by nanoDot dosimeter, indirectly by personal dosimeter (Inlight), and quick method based on the relationship with exposure duration. In one case, the doctor exceeded the threshold dose of 20 mSv/year without protective measures. Besides that, the risk of cataracts is possible when considering the cumulative dose for 30 years of work.

Radio-Guided Surgery with a New-Generation β-Probe for Radiolabeled Somatostatin Analog, in Patients with Small Intestinal Neuroendocrine Tumors.

Radio-guided surgery (RGS) holds promise for improving surgical outcomes in neuroendocrine tumors (NETs). Previous studies showed low specificity (SP) using γ-probes to detect radiation emitted by radio-labeled somatostatin analogs. We aimed to assess the sensitivity (SE) and SP of the intraoperative RGS approach using a β-probe with a per-lesion analysis, while assessing safety and feasibility as secondary objectives. This prospective, single-arm, single-center, phase II trial (NCT05448157) enrolled 20 patients diagnosed with small intestine NETs (SI-NETs) with positive lesions detected at 68Ga-DOTA-TOC positron emission tomography/computed tomography (PET/CT). Patients received an intravenous injection of 1.1 MBq/Kg of 68Ga-DOTA-TOC 10min prior to surgery. Invivo measurements were conducted using a β-probe. Receiver operating characteristic (ROC) analysis was performed, with the tumor-to-background ratio (TBR) as the independent variable and pathology result (cancer vs. non-cancer) as the dependent variable. The area under the curve (AUC), optimal TBR, and absorbed dose for the surgery staff were reported. The intraoperative RGS approach was feasible in all cases without adverse effects. Of 134 specimens, the AUC was 0.928, with a TBR cut-off of 1.35 yielding 89.3% SE and 86.4% SP. The median absorbed dose for the surgery staff was 30 µSv (range 12-41 µSv). This study reports optimal accuracy in detecting lesions of SI-NETs using the intraoperative RGS approach with a novel β-probe. The method was found to be safe, feasible, and easily reproducible in daily clinical practice, with minimal radiation exposure for the staff. RGS might potentially improve radical resection rates in SI-NETs. 68Ga-DOTATOC Radio-Guided Surgery with β-Probe in GEP-NET (RGS GEP-NET) [NCT0544815; https://classic. gov/ct2/show/NCT05448157 ].

Review of patient and staff dose reduction following the installation of a digital PETCT scanner

Review of patient and staff dose reduction following the installation of a digital PETCT scanner

Use of Airthings Wave PlusTM for radon staff dose assessment and optimisation of remediation in a workplace with intermediate radon levels

Use of Airthings Wave PlusTM for radon staff dose assessment and optimisation of remediation in a workplace with intermediate radon levels

Radiation dose to multidisciplinary staff members during complex interventional procedures

IntroductionComplex interventional radiology procedures involve extensive fluoroscopy and image acquisition while staff are in-room. Monitoring occupational radiation dose is crucial in optimization. The purpose was to determine radiation doses received by staff involved in complex interventional procedures performed in a dedicated vascular or neuro intervention room. MethodsIndividual real-time radiation dose for all staff involved in vascular and neuro-interventional procedures in adult patients was recorded over a one-year period using wireless electronic dosimeters attached to the apron thyroid shield. A reference dosimeter was attached to the C-arm near the tube housing to measure scattered, unshielded radiation. Radiology staff carried shoulder thermo-luminescent dosimeters with monthly read-out to monitor dose over time. ResultsOccupational radiation dose was measured in 99 interventional procedures. In many cases prostate artery embolization procedures exposed radiologists to high radiation doses with a median of 15.0 μSv and a very large spread, i.e. 0.2–152.5 μSv. In all procedures except uterine fibroid embolization radiographers were exposed to lower doses than those of radiologists, with endovascular aortic repair being the procedure with highest median exposure to assisting radiographers, i.e. 2.2 μSv ranging from 0.1 to 36.1 μSv. Median radiation dose for the reference dosimeter was 670 μGy while median staff dose for all procedures combined was 3.2 μGy. ConclusionRadiation doses for multiple staff were determined and the ratio between staff dose and reference dosimeter indicated proper use of shielding in general. Some high-dose procedures may need further optimization for certain staff members, especially those not primarily employed in radiology. Implications for practiceThe study provides benchmark doses that may be used widely in audits and in the ongoing effort to optimize radiation protection for staff in interventional radiology.

Assessment of personal deposited dose and particle size distribution of bacterial aerosol in kindergarten located in southern Poland

The study's primary focus lies in examining the relationship between respiratory and deposition doses of bacterial aerosols in urban kindergarten, providing valuable insights into the specific doses absorbed by individuals in different sections of their respiratory systems based on the aerodynamic diameter of bacterial particles. Samples were collected twice a week, using by an Andersen cascade impactor during autumn and winter seasons 2018/2019 resulting in a total of 1152 Petri dishes analyzed. The highest average concentration of bacterial aerosol was observed during autumn (1698 ± 663 CFU/m3) in comparison to winter months (723 ± 134 CFU/m3). Respirable doses for children and staff were 2945 and 2441 CFU/day during winter and 5988 and 4964 CFU/day during autumn, respectively. Deposition doses incorporated from empirical models for regional deposition in the respiratory tract showed that children in kindergarten absorb 33% less of bacteria into alveolar region if breath by nose instead of mouth. Additionally, risk assessment results indicate that the hazard indices for children attending kindergartens for 3 years and for staff working 25 years are below 1, suggesting minor risks associated with the inhalation of bioaerosols during autumn and winter. HI was <1, so the non-carcinogenic effects are on an acceptable level, but the indoor/outdoor ratio were 3.5 and 2.4 for autumn and winter, respectively, indicating children's and adult's exposure to bacterial aerosol should be reduced.

Assessment of extremity dose for medical staff involved in positron emission tomography/computed tomography imaging: Retrospective study.

There has been an increase in positron emission tomography (PET)/computed tomography (CT) imaging procedures, and medical workers involved in PET/CT are at increased risk of occupational exposure. Data on extremity dose exposure are limited globally. The current study aimed to evaluate the occupational radiation dose for extremities for medical workers (nurses, radiographers/radiologic technologists, and nuclear medicine physicians) working in PET/CT scanners at 5 large hospitals in Turkey. Optically stimulated luminescence (OSL) and Thermoluminescent dosimeter (TLD) ring dosimeters were used to measure equivalent dose values. Hospitals 1, 2, and 5 used OSL, and 3 and 4 used TLD. A total of 502 readings were obtained from 55 workers. In millisievert (mSv), the average annual effective dose for all workers was 14.5 ± 17.7 (0.2-157.2). A radiography technologist received a maximum dose of 157.21. Nurses received the highest average annual effective dose (15.2 ± 19.46) (0.32-65.58), followed by radiography technologists (14.7 ± 18.03) (0.4-157.2), and nuclear medicine physicians demonstrated the least dose (8.6 ± 10.5) (1.2-24.4). The results show that the extremity dose is well below the annual dose limit of 500 mSv. However, there is a wide variation in dose among the workers, underlining a need for careful assessment of working conditions to ensure safe practices for all workers.

Underestimation of Occupational Radiation Exposure During Endovascular Abdominal Aortic Aneurysm Repair.

During interventional procedures of endovascular abdominal aortic aneurysm repair (EVAR), the dosimeter was conventionally placed on chest facing toward the surgical table, instead of the main source of scatter radiation. Purpose of this study is to evaluate the underestimation of occupational radiation exposure. Phantom experiments were performed in a hybrid operating room equipped with an interventional angiography system. Electric personal dosimeters were placed at the level of eyes, chest, abdomen, and gonad of three positions, representing the principal operator (PO), assistant operator (AO), and sterile nurse (SN). Personal dose equivalent was measured with two different orientations of radiation detection, facing the table and facing the phantom, respectively. In addition to fluoroscopy, the dose produced by digital subtraction angiography was also measured to estimate the radiation exposure of routine EVAR. In this study, staff doses of 26 EVAR cases were also collected in our hospital to correlate the estimated dose. Our results show that the facing-phantom dose normalized by dose area product of patient is significantly higher than the facing-table dose when the latter is regularly seen in clinical practice. This underestimation could be even worse at a more distant position (e.g., AO and SN) as the incident angle of scatter radiation is larger. Besides, the estimated dose is highly correlated with the on-site measured dose (R 2 ~ 0.8) at chest and gonad of the PO.

Ultrasound-Based Registration for the Computer-Assisted Navigated Percutaneous Scaphoid Fixation.

An ultrasound (US)-based computer-assisted approach has the potential to improve the accuracy and precision of screw placement for the percutaneous fixation of scaphoid fractures and also reduce the radiation dose for patient and clinical staff. Therefore, a surgical plan based on preoperative diagnostic computed tomography (CT) is registered with intraoperative US images, enabling a navigated percutaneous fracture fixation. However, approaches published so far rely on semimanual methods for intraoperative registration and are limited by long computation times. To address these challenges, we propose the employment of deep learning-based methods for US segmentation and registration in order to achieve a fast and fully automated yet robust registration process. For validation of the proposed US-based approach, we first provide a comparison of methods for segmentation and registration, assess their contribution to the overall error throughout our pipeline, and, finally, evaluate navigated screw placement in an in vitro study on 3-D printed carpal phantoms. Successful screw placement has been achieved for all ten screws, with deviations from the planned axis of 1.0 ± 0.6 and 0.7 ± 0.3 mm at the distal and proximal pole, respectively. The complete automation and total duration of about 12 s also allow seamless integration of our approach into the surgical workflow.

Impact of shield location on staff and caregiver dose rates for I-131 radiopharmaceutical therapy patients

The goal of this study is to investigate the effect of the location and width of a single lead shield on the dose rate of staff and caregivers in a hospital room with an I-131 patient. The best orientation of the patient and caregiver relative to the shield was determined based on minimizing staff and caregiver radiation dose rates. Shielded and unshielded dose rates were simulated using a Monte Carlo computer simulation and validated using real-world ionisation chamber measurements. Based on a radiation transport analysis using an adult voxel phantom published by the International Commission on Radiological Protection, placing the shield near the caregiver yielded the lowest dose rates. However, this strategy reduced the dose rate in only a tiny area of the room. Furthermore, positioning the shield near the patient in the caudal direction provided a modest dose rate reduction while shielding a large room area. Finally, increased shield width was associated with decreasing dose rates, but only a four-fold dose-rate reduction was observed for standard width shields. The recommendations of this case study may be considered as potential candidate room configurations where radiation dose rates are minimized, however these findings must be weighed against additional clinical, safety, and comfort considerations.

Re-Evaluation of Patient-Sourced Radiation Doses in PET/CT.

New generation PET/CT devices provide quality images using low radiopharmaceutical activities. Dose monitoring is carried out for nuclear medicine personnel, other health personnel, and companions by determining the radiation dose emitted from low-activity patients to the environment. In particular, it is necessary to revise the working conditions of the personnel according to the radiation dose exposed. It was aimed to reevaluate the radiation dose rate transmitted to the environment from patients injected with 18F-FDG. A total of 31 patients (14F, 17M) who underwent 18F-FDG PET/CT imaging were included. The mean 18F-FDG activity of 7.26 ± 1.29 mCi was used for injection. After injection, radiation dose rates (mR/h) were measured at distances of 25, 50, 100, 150, and 200cm for 3 different periods from the level of the head, thorax, abdomen, and pelvis by using a GM counter. Additionally, biological samples such as urine and sweat were taken during 3 different periods. The activity amounts (μCi) in the samples were measured with a well-type counter. Strong correlations were calculated between normalized dose rates obtained by all regions and time. Considering the nuclear medicine staff handling time with a PET/CT patient, the average dose received by staff was calculated between a range of 0.002-0.004 mSv/pt. The radiation dose exposed to the porter and nurse was calculated as 0.049 mSv/pt for the 2nd hour and 0.001-0.007 mSv/pt for the 4th hour, respectively. The companion was exposed to a dose between 0.073-0.147 mSv and 0.024-0.048 mSv for public transport and private car transportation after 4-6 hours of injection (for 30-60 min of travel duration), respectively. For inpatients, the received dose for porters, serving 20min from a distance of 30cm for the 2nd and 4th hours after the PET/CT scan, was 0.049 mSv/pt and 0.048 mSv/pt, respectively. And for nurses serving from a 50cm distance between 1-5 minutes, these values were found to be 0.001-0.007mSv/pt, 0.001-0.007mSv/pt, and 0.001-0.006mSv/pt, respectively. The radiation dose of nuclear medicine staff, porters, nurses, and companions are found to be below the recommended dose limit by the ICRP. According to our results, there is no need for any restrictions for patients, companions, or healthcare personnel in PET/CT units.

Eye lens dose for medical staff assisting patients during computed tomography: comparison of several types of radioprotective glasses

Medical staff sometimes assists patients in the examination room during computed tomography (CT) scans for several purposes. This study aimed to investigate the dose reduction effects of four radioprotective glasses with different lead equivalents and lens shapes. A medical staff phantom was positioned assuming body movement restraint of the patient during chest CT, and Hp(3) at the eye surfaces of the medical staff phantom and inside the lens of the four types of radioprotective glasses were measured by changing the distance of the staff phantom from the gantry, eye height, and width of the nose pad. The Hp(3) at the right eye surface with glasses of 0.50–0.75 mmPb and 0.07 mmPb was approximately 83.5% and 58.0%, respectively, lower than that without radioprotective glasses. The dose reduction rates at left eye surface increased with over-glass type glasses by 14%–28% by increasing the distance from the CT gantry to the staff phantom from 25 to 65 cm. The dose reduction rates at the left eye surface decreased with over-glass type glasses by 26%–31% by increasing the height of the eye lens for the medical staff phantom from 130 to 170 cm. The Hp(3) on the left eye surface decreased by 46.9% with the widest nose pad width compared to the narrowest nose pad width for the glasses with adjustable nose pad width. The radioprotective glasses for staff assisting patients during CT examinations should have a high lead equivalent and no gap around the nose and under the front lens.