Measurement Of Radiation Exposure Research Articles

3D - Navigated percutaneous screw fixation of pelvic ring injuries – a pilot study

IntroductionScrew fixation of pelvic ring fractures is a common, but demanding procedure and navigation techniques were introduced to increase the precision of screw placement. The purpose of this case series is to demonstrate a lower screw malposition rate using percutaneous fixation of pelvic ring fractures and sacroiliac dislocations guided by navigation system based on 3D-fluoroscopic images compared to traditional imaging techniques and to evaluate the functional outcomes of this innovative procedure. Patient and Methods10 cases of disrupted pelvic ring lesions treated in our hospital from February 2018 to December 2018 were included for closed reduction and percutaneous screw fixation of using with O-Arm and the acquisition by the Navigator. Preoperative assessment was performed on the patients by means of X Ray imaging and CT scan. Routine CT was carried out on third postoperative day to evaluate screw placement. Measures of radiation exposure were extracted directly from reports provided by system. Quality of life was evaluated by SF 36-questionnaire 6 months after surgery. Results12 iliosacral- and 2 ramus pubic-screws were inserted. In post-operative CT-scans the screw position was assessed and graded using the score described by Smith. No wound infection or iatrogenic neurovascular damage were observed. No re-operations were performed. The exposure to radiation is, for the patient, slightly greater than that resulting from the use of traditional fluoroscopic systems, while it is naught for the surgical team, which at the time of image acquisition is located outside the room. Discussion and ConclusionThe execution of an intraoperative 3D-fluoroscopic scan can on its own suffice as a post-operative control examination since its accuracy is similar to that of the post-operative CT. The use of a navigated 3d fluoroscopy exposes the patient to an amount of radiation slightly greater than that of traditional fluoroscopy, but the dose is lower than a CT examination. For the operating team, exposure to radiation is naught. 3D-fluoroscopic navigation is a safe tool providing high accuracy of percutaneous screw placement for pelvic ring fractures. Finally, despite the small cohort of patients studied, the excellent results obtained regarding the patients' quality of life and the absence of complications allow us to look positively at the future of this technique, which needs further studies and improvement.

Analisis Dosis Paparan Radiasi Pada General X-Ray II Di Instalasi Radiologi Rumah Sakit Muhammadiyah Semarang

Background: This study analyzes the Radiation Dose of the General X-ray Radiology Installation at Roemani Hospital Muhammadiyah Semarang to determine the dose received by the radiographer, the community around the room and to know the value of the effectiveness of radiation protection and to determine the pattern of radiation exposure distribution in the general X-ray radiology installation room II.Methods: Measurements were taken during general X-ray exposure and without exposure using a 451P ion chamber survey. Measurement of dose data received by the radiographer and the community around the room is taken at the point of the operator’s room, service room, waiting room. As for the measurement of the effectiveness of radiation protection taken at the point in the operator’s room and the general X-ray II and the radiation distribution pattern taken at points A, B, C, D and E with a distance of 40 cm, 80 cm and 120 cm in the room general X-ray II.Result: The result of measurements in the operator room are 0.0354 µSv / hour, waiting rooms with a distance of 3.5 m at 0.0146 µSv / hour, in the service room and waiting room with a distance of 8 m at 0 µSv / hour. The value of the effectiveness of radiation protection in the operator station is 83.33% and the general X-ray II door is 84.09%.Conclusions: Based on the results of the data obtained the value of the dose received and the value of effectiveness is quite safe from excessive radiation exposure. The radiation distribution pattern, the farther the distance from the radiation source, the measured radiation exposure value will be lower.

PET quantification of brain O-GlcNAcase with [18F]LSN3316612 in healthy human volunteers

BackgroundPrevious studies found that [18F]LSN3316612 was a promising positron emission tomography (PET) radioligand for imaging O-GlcNAcase in nonhuman primates and human volunteers. This study sought to further evaluate the suitability of [18F]LSN3316612 for human clinical research.MethodsKinetic evaluation of [18F]LSN3316612 was conducted in a combined set of baseline brain scans from 17 healthy human volunteers and test-retest imaging was conducted in 10 of these volunteers; another 6 volunteers had whole-body scans to measure radiation exposure to body organs. Total distribution volume (VT) estimates were compared for the one- and two-tissue compartment models with the arterial input function. Test-retest variability and reliability were evaluated via mean difference and intraclass correlation coefficient (ICC). The time stability of VT was assessed down to a 30-min scan time. An alternative quantification method for [18F]LSN3316612 binding without blood was also investigated to assess the possibility of eliminating arterial sampling.ResultsBrain uptake was generally high and could be quantified as VT with excellent identifiability using the two-tissue compartment model. [18F]LSN3316612 exhibited good absolute test-retest variability (12.5%), but the arithmetic test-retest variability was far from 0 (11.3%), reflecting a near-uniform increase of VT on the retest scan in nine of 10 volunteers. VT values were stable after 110 min in all brain regions, suggesting that no radiometabolites accumulated in the brain. Measurements obtained using only brain activity (i.e., area under the curve (AUC) from 150–180 min) correlated strongly with regional VT values during test-retest conditions (R2 = 0.84), exhibiting similar reliability to VT (ICC = 0.68 vs. 0.64). Estimated radiation exposure for [18F]LSN3316612 PET was 20.5 ± 2.1 μSv/MBq, comparable to other 18F-labeled radioligands for brain imaging.Conclusions[18F]LSN3316612 is an excellent PET radioligand for imaging O-GlcNAcase in the human brain. Alternative quantification without blood is possible, at least for within-subject repeat studies. However, the unexplained increase of VT under retest conditions requires further investigation.

Radiation protection knowledge and practices in interventional cardiologists practicing in Africa: a cross sectional survey

We conducted a survey of doctors working in the cardiac catheterisation laboratories in Africa on their knowledge, attitude and practice with respect to radiation protection. Of seventy-two respondents contacted, 61 (84.7%) completed the questionnaire. Twenty-eight, (45.9%) were younger than 45 years. Thirty-seven, (60.6%) had less than 10 years of experience in the laboratory. Only 28 (45.9%) had undertaken radiation protection training. Fifty-eight, (95.1%) consistently used lead aprons. Forty-seven, (77%) reported consistently using thyroid shields. Ten (16.4%) consistently used radiation protection eyeglasses, whilst 36 (59%) never used them. Thermoluminescent Dosimeter badges were consistently used in 23 (37.7%). Forty-two, (68.9%) reported having ceiling mounted lead/acrylic shields. Level of radiation exposure in the most recent one year was ≤2 mSv in 14, between 2 and 20 mSv in 8 and between 20 and 30 mSv in 2, whilst 33 did not know their dose readings. The use of basic radiation protection tools as well as the knowledge and measurement of radiation exposure among interventional cardiologists working in Africa is low. The unavailability of some of the protective tools and a knowledge gap in terms of radiation protection and monitoring of self-exposure were some of the reasons for suboptimal self-protection against ionising radiation among our respondents. We suggest that initiatives be taken by all stakeholders to train this group of medical professionals in basic radiation protection to avoid unnecessary exposure to themselves, co-workers and patients.

Monitoring Radiation Exposure During Surgery with Real Time Measurements: Opportunities and Limitations

In Germany, staff exposed to radiation is monitored with official individual dosimeters. Commercially available real-time dosimeters (RTD) can be used as radiation protection dosimeters. They are worn over the apron and display the radiation dose being measured at the desired location at intervals of one second. These real-time radiation exposure measurements enable the surgical staff to take suitable measures to reduce the radiation during the operation. The objective of our study was to monitor the accuracy of the measurements taken from the real-time dosimeter and to determine the radiation scatter for individual members of the surgical staff. Prospective measurements of the operating team's exposure to radiation were carried out using a real-time dosimeter system in an operating room for vascular surgery equipped with a C-arm. Firstly the calibration of the RTD at the operating table was checked using a water phantom. Subsequently, measurements were taken during vascular interventions and surgery. When calibrated, the values of the individual RTD revealed internal significant deviations, thus a corrective factor was calculated for each RTD. In total 55 interventions on 53 patients were studied. The average dose for the RTD of the surgeon during endovascular aortic repair (n = 11) amounted to 9 ± 9 µSv (range 3.6 - 50 µSv) and during thoracic endovascular aortic repair (n = 6) 35 ± 49 µSv (3.8 - 190.3 µSv). In the case of percutaneous transluminal angioplasty of the pelvis and of the lower extremities (n = 20), the average dose for the RTD of the surgeon was 7 ± 7 µSv (1.2 - 35 µSv) and for the angiographies of the lower extremities (n = 12) at 2 ± 3 µSv (0.2 - 15.9 µSv). The real-time dosimetry provided data which contributed to the operating team changing their behaviour in the operating room. Since the dose values determined by the official dosimetry are generally very low, it is not possible to optimise the behaviour and thus the radiation protection using these dose values. This can be achieved with the radiation protection dosimeter and the dose reference levels can be defined in the new Radiation Protection Ordinance (StrlSchV). Instant feedback of the current dose rate at the place where the RTD is worn can lead to both the individual adjusting his or her personal behaviour and to optimisation of the individual's radiation protection. It is only possible to compare the measured data obtained with the RTD when calibration is carried out in advance.

Measurement of cumulative radiation exposure to children and adolescents in contact with outpatients treated with low dose radioactive iodine (131I)

BackgroundRadiation exposure from patients treated with radioactive iodine (131I) represents a radiation hazard to children and adolescents, representing the most vulnerable group of household contacts. Our aim was to calculate the cumulative radiation exposure (CRE) figures to children and adolescents sharing the same home with outpatients treated with low-dose 131I. The secondary aim was to study the demographic and educational factors that may significantly affect radiation exposure to them.ResultsThe whole number of household contacts less than 18 years was 99, out of them 49 ≤ 12 years. CRE level to children and adolescents ranged from 79 to 934 uSv. The mean, median, and 75th percentile figures were 284 ± 178 uSv, 215 uSv, and 334 uSv, respectively. The compliance of this group of contacts to radiation exposure constraint (1 mSv) was 100%. All CRE values were below this figure with 75% of them below half of this constraint. Thirteen adolescents from 12 to 18 years and 17 mothers of 23 household contacts ≤ 12 years got radiation safety instructions (RSI) directly from a radiation safety officer (RSO). This group had a significantly lower mean CRE value (184 ± 93 uSv) compared to those who got RSI from the patient or from other family members (298 ± 185 uSv) with a significant p value.ConclusionThe compliance of adolescents and children to the 1-mSv radiation exposure constraint is 100%. It is advised for adolescents and mothers of children in contact with 131I-treated patients to get direct RSI from the RSO, which is the only factor associated with significantly lower radiation exposure figures.

Is electromagnetic guidance system superior to a free-hand technique for distal locking in intramedullary nailing of tibial fractures? A prospective comparative study.

Intramedullary nailing (IMN) technique is the gold standard for the treatment of closed fractures of the lower extremity long bones. For orthopedic surgeons, one of the most important problems in IMN procedures is the fixation of distal locking screws (DLS). Accurate and rapid placement of DLSs with minimal radiation exposure is crucial. In this study, we aimed to compare the results of two different distal locking methods concerning surgery duration and radiation exposure in patients who underwent osteosynthesis of tibia fractures with IMN. In this prospective study, the results of 56 patients who met the inclusion and exclusion criteria from 72 patients were evaluated. Patients were divided into two groups according to the distal screwing method. Group 1 (n=29) comprised patients who used free-hand technique (FHT) for distal locking, while Group 2 (n=27) consisted of patients who used electromagnetic guidance system (EMGS) for distal locking. Demographic and medical data of the patients, duration of surgery time, amount of bleeding, total fluoroscopy counts, the time elapsed for distal locking, the measure of radiation exposure, number of attempts for distal screw locking, incorrect screw placements, complications and follow-up time were recorded. The groups were compared concerning demographic data and clinical results. There was no statistically significant difference between the groups about gender and side (p=0.928 and p=0.432, respectively). The mean age in Group-1 was higher than that of Group-2, and the difference was statistically significant (p=0.012). However, there was no statistically significant difference in length of hospital stay in Group-1 (p=0.140). On the other hand, in Group-2, the number of distal shots, fluoroscopy duration, effective radiation dose and operation duration were lower compared to Group-1, although this difference was not statistically significant (p=0.057, 0.073, 0.058 and 0.056, respectively). Failure was encountered in distal locking during the first attempt in three cases in Group-1 and in two cases in Group-2. Aseptic nonunion was observed in one patient in both groups. Both the FHT distal screwing technique and the EMGS distal screwing technique are highly effective methods for distal locking. The duration of operation, the duration of the fluoroscopy and radiation exposure were similar. FHT can be preferred for distal locking in conventional intramedullary nail applications, as it is effective, easy and inexpensive.

Using lean principles to introduce intraoperative navigation for scoliosis surgery.

Intraoperative 3D navigation (ION) allows high accuracy to be achieved in spinal surgery, but poor workflow has prevented its widespread uptake. The technical demands on ION when used in patients with adolescent idiopathic scoliosis (AIS) are higher than for other more established indications. Lean principles have been applied to industry and to health care with good effects. While ensuring optimal accuracy of instrumentation and safety, the implementation of ION and its associated productivity was evaluated in this study for AIS surgery in order to enhance the workflow of this technique. The aim was to optimize the use of ION by the application of lean principles in AIS surgery. A total of 20 consecutive patients with AIS were treated with ION corrective spinal surgery. Both qualitative and quantitative analysis was performed with real-time modifications. Operating time, scan time, dose length product (measure of CT radiation exposure), use of fluoroscopy, the influence of the reference frame, blood loss, and neuromonitoring were assessed. The greatest gains in productivity were in avoiding repeat intraoperative scans (a mean of 248 minutes for patients who had two scans, and a mean 180 minutes for those who had a single scan). Optimizing accuracy was the biggest factor influencing this, which was reliant on incremental changes to the operating setup and technique. The application of lean principles to the introduction of ION for AIS surgery helps assimilate this method into the environment of the operating theatre. Data and stakeholder analysis identified a reproducible technique for using ION for AIS surgery, reducing operating time, and radiation exposure. Cite this article: Bone Joint J. 2020;102-B(1):5-10.

ASSESSMENT OF AWARENESS AND PRACTICE OF IONIZING RADIATION PROTECTION PROCEDURES AMONG EXPOSED HEALTH CARE WORKERS

Introduction: Occupational exposure to ionizing radiation is the result of exposure at work sites for diagnostic and therapeutic practices. Ionizing radiation is an energy type in the form of electromagnetic waves or particles. Radiographic imaging is extremely valuable as a diagnostic tool in medical fields leading to different health hazards to health care workers (HCWs) and to the surrounding environment if safety measures are not observed. Aim of work: To assess awareness and practice of ionizing radiation protection procedures among (HCWs) occupationally exposed to ionizing radiation at Zagazig University Hospitals. Materials and methods: All HCWs (technicians, nurses, physicians, and physicists) occupationally exposed to ionizing radiation in diagnostic radiology (DR) department, Clinical Oncology and Nuclear Medicine (CO&NM) department, and Nuclear Medicine (NM) unit who accepted to share in the study were included as study population (No=195). A cross-sectional study was carried out at the previous departments in Zagazig University Hospitals. A self-administered, structured questionnaire composed of three sections, A, B and C was the study tool. Section A comprised questions regarding demographic data, section B included questions about awareness of radiation protection procedures, and section C was composed of questions about safe practices of HCWs regarding ionizing radiation exposures. Results: The study revealed that satisfactory awareness of radiation protection procedures among HCWs in the three departments was (51.3 %) with no statistically significant difference between different radiation units. But HCWs had inadequate practice score (18%) regarding the use of safety measures of radiation exposure. Satisfactory awareness of radiation protection procedures of exposed workers was highly significantly associated with higher educational level (44.2%), years of experience ≥ 10 years (36.8 %), being a physician (73.7%) and getting training courses (61.1%). Also, adequate practice of radiation protection procedures among exposed workers was found to be highly significantly associated with higher educational level (74.3%), years of experience ≥ 10 years (68.6%), being a physician (80.0%) and getting training courses (71.4%). Conclusion: satisfactory awareness about radiation protection procedures among exposed HCWs was noted while inadequate practices of radiation protection procedures in the workplace were found.

Radiation exposure to the eyes and thyroid during C-arm fluoroscopy-guided cervical epidural injections is far below the safety limit.

BackgroundThe aim of this study was to evaluate radiation exposure to the eye and thyroid in pain physicians during the fluoroscopy-guided cervical epidural block (CEB).MethodsTwo pain physicians (a fellow and a professor) who regularly performed C-arm fluoroscopy-guided CEBs were included. Seven dosimeters were used to measure radiation exposure, five of which were placed on the physician (forehead, inside and outside of the thyroid protector, and inside and outside of the lead apron) and two were used as controls. Patient age, sex, height, and weight were noted, as were radiation exposure time, absorbed radiation dose, and distance from the X-ray field center to the physician.ResultsOne hundred CEB procedures using C-arm fluoroscopy were performed on comparable patients. Only the distance from the X-ray field center to the physician was significantly different between the two physicians (fellow: 37.5 ± 2.1 cm, professor: 41.2 ± 3.6 cm, P = 0.03). The use of lead-based protection effectively decreased the absorbed radiation dose by up to 35%.ConclusionsAlthough there was no difference in radiation exposure between the professor and the fellow, there was a difference in the distance from the X-ray field during the CEBs. Further, radiation exposure can be minimized if proper protection (thyroid protector, leaded apron, and eyewear) is used, even if the distance between the X-ray beam and the pain physician is small. Damage from frequent, low-dose radiation exposure is not yet fully understood. Therefore, safety measures, including lead-based protection, should always be enforced.

Transfer of naturally occurring radionuclides from soil to wild forest flora in an area with enhanced legacy and natural radioactivity in Norway.

A study of transfer of naturally occurring radioactive materials (NORM), thorium, uranium and their progeny, from soil to wild plant species was performed to evaluate the environmental impact in an area of enhanced natural and legacy radioactivity in Norway. Three sites were chosen for the study: NORM legacy mining, undisturbed 232Th-rich site and reference site. Tissue concentrations, transfer factors and radiation exposure doses were determined in nine wild plant species. High soil activity concentrations of NORM, statistically indistinguishable, were measured at legacy NORM and undisturbed 232Th-rich sites, respectively, while soil from the reference site exhibited a statistically lower activity concentration. Heterogeneous soil radionuclide distributions were observed. The mobile soil fraction of investigated radionuclides was significantly lower, but properly reflected in measured plant uptake. Plant tissue activity concentrations of NORM were significantly higher at both investigated 232Th-rich sites in comparison to the reference site and varied per plant species and analyzed radionuclide, for instance, from non-detectable 232Th in tree needles and leaves to significantly elevated values of measured 210Po in lichens. As expected, plant roots served as a natural translocation barrier, as the concentration of radionuclides in the analyzed samples was up to 88-fold higher than that in the corresponding aboveground plants. Transfer factors for 232Th, 238U, 226,228Ra and 210Po in the aboveground plants ranged broadly from 4 × 10-5 to 1 × 10-2; 1 × 10-4 to 4 × 10-2, 1.07 × 10-3 to 1.08; 2.18 × 10-2 to 9.53 × 10-2 and 9.18 × 10-2 to 9.69, respectively. Radiological exposure dose rates, calculated using the ERICA tool and site-specific data, were from 1 to 23 μGy h-1. Due to elevated NORM levels in analyzed plants, measured radiation exposure dose rates were higher than those of worldwide background biota. Still, the uptake of NORM, demonstrated in the current study, is not expected to cause significant changes at population levels in wild plant species.

Firefighters' and Emergency Medical Service Personnel's Knowledge and Training on Radiation Exposures and Safety: Results from a Survey.

Little is known about first responders' knowledge of radiation exposure and the training they receive regarding radiological events. Firefighters and emergency medical services (EMS) personnel were surveyed in July 2018 to February 2019 regarding their knowledge of radiation exposure and the radiological event training they had received. Knowledge was assessed using 15 true-false questions. Five types of radiological event training were assessed. A Mann-Whitney test assessed differences in training received by occupation. A linear regression identified predictors of knowledge scores. A total of 433 individuals completed the survey (response rate = 82.9%). Knowledge scores ranged from 5 to 13, with an average of 8.6. Predictors of knowledge included having received more training on radiological transportation incidents or improvised nuclear devices, and being a firefighter. About a quarter (23.6%, n = 102) had not received any of the 5 types of radiological event training. Firefighters received more training than EMS personnel except on nuclear reactor incidents. Only 14% had participated in a radiological event exercise. First responders' knowledge of radiation exposure and prevention measures is low, and many have received either no or very little training on radiological events. The lack of radiation exposure knowledge and radiological event training received, as identified in this study, could result in increased mortality rates. First responder agencies should provide additional radiological event training and exercise opportunities.

1148 Radiation Exposure in Pediatric Population During Endoscopic Retrograde Cholangiopancreaticography (ERCP)

INTRODUCTION: Radiation exposure during ERCP has been well studied in adult population but not specifically in the pediatric population. Use of fluoroscopy during ERCP exposes patients to ionizing radiation with potential for deleterious health consequences including risk of malignancy in future. Based on recent studies, fluoroscopy time (FT) is considered as an imperfect measure of radiation exposure. There are other factors like DAP (dose area product), effective dose (ED), Radiation dosage (RD), which need to be considered in assessing the radiation exposure to patients. The primary aim of this study is to assess the overall radiation exposure to pediatric population during ERCP and to determine if there is a difference between the dose received between adult population and pediatric population. METHODS: All procedures performed at our center between 2015 and 2017 were included in this study. Most of the ERCP’s were performed by one high volume endoscopist performing >200 ERCP’s per year in adult population. All ERCPs were performed in the same fluoroscopy unit equipped with an undercouch x- ray tube, collimator, an overcouch image intensifier and image receiver, and a digital image system allowing automatic brightness/exposure control and last image hold. ERCP-associated radiation data are automatically recorded in preinstalled manufacturer-provided software in an operator console unit. This unit automatically records FT (minutes), total radiation dose (TRD) (mGy), and DAP (Gy-cm2). DAP provides an easily measurable estimate of the total radiation delivered to patients undergoing ERCP. Fluoroscopy equipment was entirely operated by the endoscopist. RESULTS: Total of 143 pediatric patients were included in the study (n = 143). Mean age was 15.2. The overall median FT was 1.4 minutes. The overall median TRD was 25.375 mGy. The overall median DAP was 6.077 Gy-cm2. The overall ED received by patients during ERCPs was 1.58002 mSv. Age group < =10 appeared to have received less ED and TRD compared to age group 11-18. When compared to adult population, pediatric age population are exposed to more ED and DAP. CONCLUSION: Radiation exposure during ERCP should be kept to minimum and there is a strong need to create more awareness among endoscopists about how to use to different settings (by selecting a low frame rate and magnification setting, by using collimation, etc) with newer fluoroscopy machines which can decrease the overall radiation exposure.

S-Glutathionylated Serine Proteinase Inhibitors as Biomarkers for Radiation Exposure in Prostate Cancer Patients

In biological tissues, radiation causes the formation of reactive oxygen species (ROS), some of which lead to sequential oxidation of certain protein cysteine residues. Resultant cysteinyl radicals are subject to post-translational modification through S-glutathionylation. The present clinical trial was designed to determine if S-glutathionylated serine protease inhibitors (serpins) in blood could be used as biomarkers of exposure to radiation. 56 male prostate cancer patients treated with radiotherapy were enrolled in the trial and levels of S-glutathionylated serpins A1 and A3 were assessed by immunoblotting. Patients were classified into three groups: (1) external beam radiation therapy (EBRT); (2) brachytherapy (BT); (3) both EBRT and BT. Prior to treatment, baseline plasma levels of both unmodified and S-glutathionylated serpins were similar in each group. We identified elevated plasma levels of S-glutathionylated serpin A1 monomer, trimer and serpin A3 monomer in patient blood following radiation. Maximal increased levels of these S-glutathionylated serpins were correlated with increased duration of radiotherapy treatments. We conclude that it is practical to quantify patient plasma S-glutathionylated serpins and that these post-translationally modified proteins are candidate biomarkers for measuring radiation exposure. This provides a platform for use of such biomarkers in trials with the range of drugs that, like radiation, produce ROS.

TCT-200 Reduced Radiation Exposure in the Cardiac Catheterization Laboratory Using Combination of both Horizontal and a Novel Vertical Radiation Shield

Radiation exposure in the cardiac catheterization laboratory (CCL) is a safety risk. In this study, we investigated the impact of a novel sterile Vertical Radiation Shield (VRS) on operator radiation exposure. Prior to a coronary procedure, a dosimeter measured radiation exposure on a mannequin

Impact of Patient and Procedure-Related Factors on Radiation Exposure from Uterine Artery Embolization.

To determine the range of radiation dose metrics for uterine artery embolization and the impact of patient and procedure factors on those measures. Procedure records of 515 uterine embolization procedures were reviewed and various metrics recorded, including patient demographics, body mass index (BMI), radiation exposure measures and procedure-related details. Descriptive statistics were used to summarize the measures, and appropriate parametric and nonparametric tests were used to compare and assess the correlation between the measures and the cumulative dose (CD), dose area product and fluoroscopy time (FT). Multivariable regression analysis was used to assess the impact of individual factors on the measures of radiation dose. The strongest correlation among the measures compared were between CD and BMI (r = 0.70), while the correlation between BMI and FT was weak (r = 0.23). Dose was higher for those procedures done with aortography and those who had TAGM as the embolic agent. Multivariable analysis demonstrated an increase of 7.4% in CD for each increase in BMI, 5.9% for each increase in cm uterine length. FT was impacted to a lesser extent, with an increase of 2.8% per unit BMI. Increasing procedure time had a greater impact on FT (r = 0.56) than on CD (r = 0.33). Among the measured variables, BMI had the greatest impact on CD and has a substantial impact on the risk of radiation-induced skin injury, even without prolonged FT.

Radiation exposure in the treatment of pediatric supracondylar humerus fractures.

To determine the factors that influence radiation exposure during repair of supracondylar humerus fractures. Medical records of almost 200 children with supracondylar fractures were retrospectively analyzed for variables correlated with fluoroscopy time and radiation dose as measures of radiation exposure. There was no statistically significant difference in fluoroscopy time (27 vs. 22s p = 0.345) or direct radiation dose (0.394 vs. 0.318mSv p = 0.290) between uniplanar and biplanar C-arm use. No statistically significant differences in fluoroscopy time or radiation dose were found for surgical technique, comorbid ipsilateral fractures, preoperative neurovascular compromise, or resident participation. There was a significant 8.3s increase in fluoroscopy time (p = 0.022) and 0.249mSv increase in radiation dose (p = 0.020) as the fracture type increased from II to III. An increase in one pin during CRPP resulted in a statistically significant 10.4s increase in fluoroscopy time and a 0.205mSv increase in radiation dose. There were significant differences between the physician with the lowest fluoroscopy time and radiation dose compared with the physicians with the two highest values for both fluoroscopy time and radiation dose (p < 0.01). We found no significant difference in direct radiation exposure or fluoroscopy time when comparing biplanar to uniplanar C-arm use, resident participation, preoperative neurovascular compromise, or for comorbid ipsilateral fractures. Both outcomes increased significantly as fracture type increased from II to III and as the number of pins used during CRPP increased. Both outcomes were significantly different between the surgeons performing CRPP.

Chemical dosimeters

Measuring radiation exposure has long been a priority in radiation therapy. Over the last 115 years numerous chemical-based dosimeters have been developed to measure radiation exposure. These dosimeters contain either metal complexes or leuco dyes. Among the factors which influence dose sensitivity and color stability in leuco dye based dosimeters are chemical structure and the solvent content in the formulation.

The factors contributing to the total radiation exposure of patients during uterine artery embolisation.

Uterine artery embolisation (UAE) is an interventional angiography procedure for the treatment of symptomatic fibroids and/or adenomyosis in women. UAE is a less invasive and non‐surgical alternative to hysterectomy or myomectomy. However, ionising radiation is used for both fluoroscopic and angiographic image guidance to visualise and access the uterine arteries for embolisation and treatment of these benign conditions. Identifying the contributors and implementing dose reduction techniques are particularly important as UAE patients are usually of child‐bearing age. The purpose of this review was to examine the progression of literature on radiation exposure measurements and identifying the factors contributing to the total radiation exposure of female patients undergoing UAE. A Medline, ProQuest Central, ScienceDirect and Scopus database search from 2000 to 2018 was performed and forty articles were deemed acceptable for review following the inclusion and exclusion criteria set. UAE is a viable alternative to hysterectomy and myomectomy, as the reviewed literature demonstrated that the reported radiation exposure doses appear to be below the threshold for any deterministic radiation risks. The total radiation exposure of UAE patients is affected independently by multiple patient, operator expertise and technique, angiographic imaging and x‐ray unit variables. Uterus preservation can be attained post‐UAE with dose reduction and optimisation, however, a longitudinal study on UAE patients and their risk of radiation‐induced deterministic and/or stochastic effects is recommended.

Measuring the radiation exposure of Norwegian reindeer under field conditions

Models and approaches have been developed to predict radiation exposure of wildlife under field conditions. However, there have been few attempts to directly measure radiation exposure of wildlife in the field and confirm the doses predicted by models. This is a potential issue for stakeholder acceptance of modelling-based assessments. Here is presented a comprehensive study comparing the results of different dosimeters fitted to free-ranging reindeer inhabiting an area that received comparatively high radiocaesium deposition from the 1986 Chernobyl accident. The external dose of reindeer was measured using the four dosimeter types in aluminium box mounted on the GPS collar. The measurements were compared with two model predictions: (i) external dose to reindeer across the entire range area of the herd; and (ii) external doses of individual reindeer predicted using GPS tracking data to determine locations. It was found that although significant differences between the estimates of the various dosimeters were found these were small with no practical implication. Also, the mean predicted external doses using the GPS tracking data were not significantly different to estimates from two of the four passive dosimeter results. The average external dose predicted across the herd area was significantly lower than doses recorded by the dosimeters and also estimates using GPS data to determine reindeer location (and hence exposure). For 137Cs the average external dose from the GPS tracking data was about twice that predicted across the herd area, because collared animals favoured the more contaminated area of the study site. This suggests that in some circumstances the assumption of averaging contamination over an assumed home range within assessments may be inadequate though this would need to be balanced against other uncertainties. Natural radiation was the greatest contribution to reindeer exposure and a function of the high altitude.