Comparison of shielding effects of over-glasses-type and regular eyewear in terms of occupational eye dose reduction.

Given the new recommendations for occupational eye lens doses, various lead glasses have been used to reduce irradiation of interventional radiologists. However, the protection afforded by lead glasses over prescription glasses (thus over-glasses-type eyewear) has not been considered in detail. We used a phantom to compare the protective effects of such eyewear and regular eyewear of 0.07 mm lead-equivalent thickness. The shielding rates behind the eyewear and on the surface of the left eye of an anthropomorphic phantom were calculated. The left eye of the phantom was irradiated at various angles and the shielding effects were evaluated. We measured the radiation dose to the left side of the phantom using RPLDs attached to the left eye and to the surface/back of the left eyewear. Over-glasses-type eyewear afforded good protection against x-rays from the left and below; the average shielding rates on the surface of the left eye ranged from 0.70-0.72. In clinical settings, scattered radiation is incident on physicians' eyes from the left and below, and through any gap in lead glasses. Over-glasses-type eyewear afforded better protection than regular eyewear of the same lead-equivalent thickness at the irradiation angles of concern in clinical settings. Although clinical evaluation is needed, we suggest over-glasses-type Pb eyewear even for physicians who do not wear prescription glasses.

Evaluation of radiation dose to the lens in interventional cardiology physicians before and after dose limit regulation changes.

In response to the International Commission on Radiological Protection, which lowered the lens equivalent dose limit, Japan lowered the lens dose limit from 150 mSv y-1to 100 mSv/5 years and 50 mSv y-1, with this new rule taking effect on 1 April 2021. DOSIRIS®is a dosimeter that can accurately measure lens dose. Herein, we investigated lens dose in interventional cardiology physicians 1 year before and after the reduction of the lens dose limit using a neck dosimeter and lens dosimeter measurements. With an increase in the number of cases, both personal dose equivalent at 0.07 mm depth [Hp(0.07), neck dosimeter] and personal dose equivalent at 3 mm depth [Hp(3), lens dosimeter] increased for most of the physicians. The Hp(3) of the lens considering the shielding effect of the Pb glasses using lens dosimeter exceeded 20 mSv y-1for two of the 14 physicians. Protection from radiation dose will become even more important in the future, as these two physicians may experience radiation dose exceeding 100 mSv/5 years. The average dose per procedure increased, but not significantly. There was a strong correlation between the neck dosimeter and lens dosimeter scores, although there was no significant change before and after the lens dose limit was lowered. This correlation was particularly strong for physicians who primarily treated patients. As such, it is possible to infer accurate lens doses from neck doses in physicians who primarily perform diagnostics. However, it is desirable to use a dosimeter that can directly measure Hp(3) because of the high lens dose.

Evaluation of a New Real-Time Dosimeter Sensor for Interventional Radiology Staff.

In 2011, the International Commission on Radiological Protection (ICRP) recommended a significant reduction in the lens-equivalent radiation dose limit, thus from an average of 150 to 20 mSv/year over 5 years. In recent years, the occupational dose has been rising with the increased sophistication of interventional radiology (IVR); management of IVR staff radiation doses has become more important, making real-time radiation monitoring of such staff desirable. Recently, the i3 real-time occupational exposure monitoring system (based on RaySafeTM) has replaced the conventional i2 system. Here, we compared the i2 and i3 systems in terms of sensitivity (batch uniformity), tube-voltage dependency, dose linearity, dose-rate dependency, and angle dependency. The sensitivity difference (batch uniformity) was approximately 5%, and the tube-voltage dependency was <±20% between 50 and 110 kV. Dose linearity was good (R2 = 1.00); a slight dose-rate dependency (~20%) was evident at very high dose rates (250 mGy/h). The i3 dosimeter showed better performance for the lower radiation detection limit compared with the i2 system. The horizontal and vertical angle dependencies of i3 were superior to those of i2. Thus, i3 sensitivity was higher over a wider angle range compared with i2, aiding the measurement of scattered radiation. Unlike the i2 sensor, the influence of backscattered radiation (i.e., radiation from an angle of 180°) was negligible. Therefore, the i3 system may be more appropriate in areas affected by backscatter. In the future, i3 will facilitate real-time dosimetry and dose management during IVR and other applications.

Cardiologist's exposure to radiation in cath lab measured with InstadoseTMdosimeter.

INTRODUCTION: complex fluoroscopy-guided interventional procedures in cardiology are known to result in higher radiation doses for patients and staff. PURPOSE: to estimate the equivalent dose received in different regions of the cardiologist's body in catheterism (CATH) and percutaneous coronary intervention (PCI) procedures, as well as to evaluate the effectiveness of monitoring the doses in the catheritization laboratory (cath lab) using a direct ion storage dosimeter. MATERIALS AND METHODS: the InstadoseTMand the thermoluminescent dosimeters (TLD-100) were fixed simultaneously in the following regions of the cardiologist's body: near the eyes (left and right), the trunk region (over the lead apron) and the left ankle. Occupational doses were recorded during 86 procedures (60% CATH). RESULTS: catheterization procedures showed third quartile dose values near to the left eye region equal to 0.10 mSv (TLD-100) and 0.12 (InstadoseTM) and for intervention 0.15 mSv (TLD-100 and InstadoseTM). The doses measured in the trunk region, over the lead apron, were about 13% higher for catheterization procedures and 20% higher for intervention procedures compared to left eye region measurements. The Wilcoxon-Mann-Whitney test was applied for unpaired data for all body regions, comparing the data obtained between the TLD-100 and InstadoseTMdosimeters. For CATH and PCI, the responses of the TLD-100 and InstadoseTMdosimeters are considered equal for all analysed regions (p> 0.05) with the exception of the right eye region. CONCLUSION: the InstadoseTMpassive dosimeter can be useful as a complementary assessment in the monitoring of a cardiologist's personal occupational doses in the cath lab.

Protected and Unprotected Radiation Exposure to the Eye Lens During Endovascular Procedures in Hybrid Operating Rooms.

OBJECTIVE: Radiation cataract has been observed at lower doses than previously thought, therefore the annual limit for equivalent dose to the eye lens has been reduced from 150 to 20 mSv. This study evaluated radiation exposure to the eye lens of operators working in a hybrid operating room before and after implementation of a dose reduction program. METHODS: From April to October 2019, radiation exposure to the first operator was measured during all consecutive endovascular procedures performed in the hybrid operating room using BeOSL Hp(3) eye lens dosimeters placed both outside and behind the lead glasses (0.75 mm lead equivalent). Measured values were compared with data from a historic control group from the same hospital before implementation of the dose reduction program. RESULTS: A total of 181 consecutive patients underwent an endovascular procedure in the hybrid operating room. The median unprotected eye lens dose (outside lead glasses) of the main operator was 0.049 mSv for endovascular aortic repair (EVAR) (n = 30), 0.042 mSv for thoracic endovascular aortic repair (TEVAR) (n = 23), 0.175 mSv for complex aortic fenestrated or branched endovascular procedures (F/BEVAR; n = 15), and 0.042 mSv for peripheral interventions (n = 80). Compared with the control period, EVAR had 75% lower, TEVAR 79% lower, and F/BEVAR 55% lower radiation exposure to the unprotected eye lens of the first operator. The lead glasses led to a median reduction in the exposure to the eye lens by a factor of 3.4. CONCLUSION: The implementation of a dose reduction program led to a relevant reduction in radiation exposure to the head and eye lens of the first operator in endovascular procedures. With optimum radiation protection measures, including a ceiling mounted shield and lead glasses, more than 440 EVARs, 280 TEVARs, or 128 FEVARs could be performed per year before the dose limit for the eye lens of 20 mSv was reached.

Uncertainties in occupational eye lens doses from dosimeters over the apron in interventional practices.

It is relevant to estimate the uncertainties in the measurement of eye lens doses from a personal dosimeter over the protective apron without using additional dosimetry near the eyes. Additional dosimetry for interventionists represents a difficulty for routine clinical practice. This study analyses the estimated eye doses from dosimeter values taken at chest level over the apron and their uncertainties. Measurements ofHp(0.07) using optically stimulated luminescence dosimeters located on the chest over the apron and on the glasses (in the inner and outer part of the protection) were taken from ten interventionalists in a university hospital, in the period 2018-2019 during standard clinical practice. For a total sample of 133 interventional procedures included in our study, the ratio between theHp(0.07) on the glasses (left-outer side) and on the chest over the apron had an average of 0.74, with quartiles of 0.47, 0.64, 0.88. Statistically significant differences were found among operators using the U-Mann-Whitney test. The average transmission factor for the glasses was 0.30, with quartiles of 0.21, 0.25, and 0.32. Different complexity in the procedures, in the quality of the scatter radiation and in the individual operational practices, involve a relevant dispersion in the results for lens dose estimations from the over apron dosimeter. Lens doses may be between a 64% and an 88% of the over apron dosimeter values (using median or 3rd quartile). The use of 88% may be a conservative approach.

Radiation exposure to the lens of the eye for Japanese nuclear power plant workers.

In Japan, the radiation-dose limit for the lens of the eye was revised in April 2021. Consequently, for workers, the numerical values of the equivalent dose to the lens of the eye are equal to those of the effective dose. Radiation workers, radiation safety officers and licensees must comply with regulations related to radiation protection and optimize protection. The new guidelines on dose monitoring of the lens of the eye developed by the Japan Health Physics Society recommend for the dose to be estimated near the eye for accurate estimation, when the dose to the lens approaches or exceeds the management criteria. However, there is limited information regarding the non-uniform exposure of nuclear power plant workers. In this study, the dose equivalents of high-dose-rate workplaces and the personal doses of 88 workers were estimated at four Japanese commercial nuclear power plant sites (RWR: 3 units and BWR: 3 units) and the dose to the lens of the eye and the exposure situations of the workers were analyzed.

Report of IRPA task group on issues and actions taken in response to the change in eye lens dose limit.

In 2018, the International Radiation Protection Association (IRPA) established its third task group (TG) on the implementation of the eye lens dose limit. To contribute to sharing experience and raising awareness within the radiation protection community about protection of workers in exposure of the lens of the eye, the TG conducted a questionnaire survey and analysed the responses. This paper provides an overview of the results of the questionnaire.

[Evaluating Eye Lens Dose of Neurovascular and Cardiac Electrophysiology Interventional Physician].

PURPOSE: The International Commission on Radiological Protection recommended that interventional radiologies (IRs) have high radiation doses and that staff may also be exposed to high doses. In the present study, we measured the radiation exposure dose [3 mm dose equivalent, Hp (3) ] in the eye using an appropriate dosimeter placed next to the physician' s eye during neurovascular intervention procedure (Neuro-IR) and interventional cardiac electrophysiology procedure (EP-IR). METHOD: Physicians wore a direct eye dosemeter just lateral to the left eye and an additional direct eye dosemeter outside the radiation protective glasses close to their left eye. Additionally, a neck badge [0.07 mm dose equivalent, Hp (0.07) ] was worn outside the protective apron to the left of the neck, to compare the direct eye dosimeter estimated doses. The occupational eye lens dose was evaluated over a period of 6-month. RESULTS: The maximum Hp (3) of the Neuro-IR physician was estimated 5.1 mSv without the radiation protective glasses and 1.6 mSv with the radiation protective glasses. On the other hand, the maximum Hp (3) of the EP-IR physician was estimated 29 mSv without the radiation protective glasses and 15 mSv with the radiation protective glasses. CONCLUSION: Physicians eye lens dose [Hp (3) ] tended to be overestimated by the neck badge measurements [Hp (0.07)]. A correct evaluation of the lens dose [Hp (3) ] using the direct eye dosimeter is recommended. Although we found a positive correlation between Hp (0.07) and Hp (3), the value of R2 in the regression equation is low, we recommended that the eye lens dose estimated carefully from Hp (0.07).

Assessment of scatter radiation dose and absorbed doses in eye lens and thyroid gland during digital breast tomosynthesis.

Digital breast tomosynthesis (DBT) is an alternative tool for breast cancer screening; however, the magnitude of peripheral organs dose is not well known. This study aimed to measure scattered dose and estimate organ dose during mammography under conventional (CM) and Tomo (TM) modes in a specific DBT system. Optically stimulated luminescence dosimeters (OSLDs), whose responses were corrected using a parallel-plate ionization chamber, were pasted on the surface of custom-made polymethyl methacrylate (PMMA) and RANDO phantoms to measure entrance surface air kerma (ESAK). ESAK measurements were also acquired with a 4.5-cm thick breast phantom for a standard mammogram. Organ dose conversion factors (CFD ) were determined as ratio of air kerma at a specific depth to that at the surface for the PMMA phantom and multiplied by the ratio of mass energy absorption coefficients of tissue to air. Normalized eye lens and thyroid gland doses were calculated using the RANDO phantom by multiplying CFD and ESAK values. Maximum variability in OSLD response to scatter radiation from the DBT system was 33% in the W/Rh spectrum and variations in scattered dose distribution were observed between CM and TM. The CFD values for eye lens and thyroid gland ranged between 0.58 to 0.66 and 0.29 to 0.33, respectively. Mean organ doses for two-view unilateral imaging were 0.24 (CM) and 0.18 (TM) µGy/mAs for the eye lens and 0.24 (CM) and 0.25 (TM) µGy/mAs for the thyroid gland. Higher organ doses were observed during TM compared to CM as the automatic exposure control (AEC) system resulted in greater total mAs values in TM.

The new lens dose limit: implication for occupational radiation protection.

AIM AND OBJECTIVES: The aim of this article was to explore the implications of the new Euratom dose limit for occupational radiation protection in the context of medical occupational radiation exposures. The European Directive 2013/59/Euratom takes into account the new recommendations on reduction in the dose limit for the lens of the eye for planned occupational exposures released in 2012 by the International Commission on Radiological Protection (ICRP 118). MATERIALS AND METHODS: Different dose-monitoring procedures and devices were considered. Occupational eye lens doses reported by previous studies were analyzed, mainly considering workers involved in interventional procedures with X-rays. The current status of eye lens radiation protection and the main methods for dose reduction were investigated. RESULTS: The analysis showed that the workers, potentially exceeding the new limit, are clinical staff performing interventional procedures with a relatively high X-ray dose. Regarding radiological protection issues, the considered literature reports that the proper use of personal protective equipment may reduce the eye lens absorbed dose. CONCLUSION: The evaluation of the occupational eye lens dose is essential to establish which method of personal dose monitoring should be preferred. Furthermore, education and training about the right use of personal protective equipment are important for medical staff working with ionizing radiation.

Assessment of occupational radiation dose in interventional settings.

INTRODUCTION: In light of both current Italian radioprotection law and the new European Directive, radiation dose monitoring was carried out on the interventional staff, of the new Papa Giovanni XXIII Hospital in Bergamo, Italy, potentially exposed to high radiation levels. METHODS: Interventional activities were mapped and personal dose data were collected for three years using thermo-luminescent dosimeters. Effective dose (ED) to whole body and equivalent dose (HT) to hands and eye lenses were estimated from Hp(10) and Hp(0.07) measurements. RESULTS: During the monitoring period, individual annual cumulative ED ranged from 0.2 to 9.3 mSv for radiologists (N=4), from 0.1 to 4.6 mSv for neuroradiologists (N=4), from 0.1 to 2.0 mSv for nurses (N=11), and from less than 0.1 to 1.2 mSv for radiographers (N=14). Individual annual HTs to hands ranged from 1.5 to 282.0 mSv for radiologists, from 0.5 to 99.7 mSv for neuroradiologists, from 1.9 to 12.8 mSv for nurses and from 0.7 to 12 mSv for radiographers. Individual annual HTs to eye lenses ranged from 1.1 to 110.9 mSv, from 0.6 to 58.3 mSv, from 0.1 to 8.6 mSv, from less than 0.1 to 11.7 mSv for radiologists, neuroradiologists, nurses and radiographers respectively. CONCLUSIONS: The doses received by medical doctors were higher than those for the other two groups. The Italian dose limits have been respected for all operator categories. The eye lens dose limit of the new European Directive (BSS 2013) was exceeded in 2013 by three medical doctors, prompting prescription of protective glasses. Since 2015 also this new limit has been observed.

Characterizing endourologist learning curve during percutaneous nephrolithotomy: implications on occupational dose and patients.

In this study we have characterized the learning curve of percutaneous nephrolithotomy procedures over 301 cases for six years. Different surrogate parameters of clinical expertise have been used, such as dose area product, total procedure time, fluoroscopy time and personal equivalent doses. In addition, two different endourologists have been monitored; one of whom was subjected to a specific Radiation Protection training (ICRP 85). Eye lens dose is estimated from thermoluminescent dosimeters. Significant differences are observed between both endourologists, especially in the fluoroscopy time. Finally, both entrance skin dose and effective doses of patients have been determined.

Clinical evaluation of a dose monitoring software tool based on Monte Carlo Simulation in assessment of eye lens doses for cranial CT scans.

INTRODUCTION: The aim of this study was to verify the results of a dose monitoring software tool based on Monte Carlo Simulation (MCS) in assessment of eye lens doses for cranial CT scans. METHODS: In cooperation with the Federal Office for Radiation Protection (Neuherberg, Germany), phantom measurements were performed with thermoluminescence dosimeters (TLD LiF:Mg,Ti) using cranial CT protocols: (I) CT angiography; (II) unenhanced, cranial CT scans with gantry angulation at a single and (III) without gantry angulation at a dual source CT scanner. Eye lens doses calculated by the dose monitoring tool based on MCS and assessed with TLDs were compared. RESULTS: Eye lens doses are summarized as follows: (I) CT angiography (a) MCS 7 mSv, (b) TLD 5 mSv; (II) unenhanced, cranial CT scan with gantry angulation, (c) MCS 45 mSv, (d) TLD 5 mSv; (III) unenhanced, cranial CT scan without gantry angulation (e) MCS 38 mSv, (f) TLD 35 mSv. Intermodality comparison shows an inaccurate calculation of eye lens doses in unenhanced cranial CT protocols at the single source CT scanner due to the disregard of gantry angulation. On the contrary, the dose monitoring tool showed an accurate calculation of eye lens doses at the dual source CT scanner without gantry angulation and for CT angiography examinations. CONCLUSION: The dose monitoring software tool based on MCS gave accurate estimates of eye lens doses in cranial CT protocols. However, knowledge of protocol and software specific influences is crucial for correct assessment of eye lens doses in routine clinical use.

Estimating brain and eye lens dose for the cardiologist in interventional cardiology-are the dose levels of concern?

OBJECTIVES: To establish conversion coefficients (CCs), between mean absorbed dose to the brain and eye lens of the cardiologist and the air kerma-area product, PKA, for a set of projections in cardiac interventional procedures. Furthermore, by taking clinical data into account, a method to estimate the doses per procedure, or annual dose, is presented. METHODS: Thermoluminescence dosimeters were used together with anthropomorphic phantoms, simulating a cardiologist performing an interventional cardiac procedure, to estimate the CCs for the brain and eye lens dose for nine standard projections, and change in patient size and x-ray spectrum. Additionally, a single CC has been estimated, accounting for each projections fraction of use in the clinic and associated PKA using clinical data from the dose monitoring system in our hospital. RESULTS: The maximum CCs for the eye lens and segment of the brain, is 5.47 µGy/Gycm2 (left eye lens) and 1.71 µGy/Gycm2 (left brain segment). The corresponding weighted CCs: are 3.39 µGy/Gycm2 and 0.89 µGy/Gycm2, respectively. CONCLUSIONS: Conversion coefficients have been established under actual scatter conditions, showing higher doses on the left side of the operator. Using modern interventional x-ray equipment, interventional cardiac procedures will not cause high radiation dose levels to the operator when a ceiling mounted shield is used, otherwise there is a risk that the threshold dose values for cataract will be reached. ADVANCE IN KNOWLEDGE: In addition to the CCs for the different projections, methods for deriving a single CC per cardiac interventional procedure and dose per year were introduced.

Effect of backscatter radiation on the occupational eye-lens dose.

We quantified the level of backscatter radiation generated from physicians' heads using a phantom. We also evaluated the shielding rate of the protective eyewear and optimal placement of the eye-dedicated dosimeter (skin surface or behind the Pb-eyewear). We performed diagnostic X-rays of two head phantoms: Styrofoam (negligible backscatter radiation) and anthropomorphic (included backscatter radiation). Radiophotoluminescence glass dosimeters were used to measure the eye-lens dose, with or without 0.07-mm Pb-equivalent protective eyewear. We used tube voltages of 50, 65 and 80 kV because the scattered radiation has a lower mean energy than the primary X-ray beam. The backscatter radiation accounted for 17.3-22.3% of the eye-lens dose, with the percentage increasing with increasing tube voltage. Furthermore, the shielding rate of the protective eyewear was overestimated, and the eye-lens dose was underestimated when the eye-dedicated dosimeter was placed behind the protective eyewear. We quantified the backscatter radiation generated from physicians' heads. To account for the effect of backscatter radiation, an anthropomorphic, rather than Styrofoam, phantom should be used. Close contact of the dosimeter with the skin surface is essential for accurate evaluation of backscatter radiation from physician's own heads. To assess the eye-lens dose accurately, the dosimeter should be placed near the eye. If the dosimeter is placed behind the lens of the protective eyewear, we recommend using a backscatter radiation calibration factor of 1.2-1.3.

Evaluation of operator eye exposure and eye protective devices in interventional radiology: Results on clinical staff and phantom.

PURPOSE: To assess occupational eye lens dose based on clinical monitoring of interventional radiologists and to assess personal protective eyewear (PPE) efficacy through measurements with anthropomorphic phantom. METHODS: Two positions of the operator with respect to X-ray beam were simulated with phantom. Dose reduction factor (DRF) of four PPE was assessed, as well as correlation between eye lens and whole-body doses. Brain dose was also assessed. Five radiologists were monitored for one-year clinical procedures. All subjects were equipped with whole-body dosimeter placed over lead apron at the chest level and eye lens dosimeter placed over the left side of the PPE. Kerma-Area Product (KAP) of procedures performed during the monitoring period was recorded. The correlation of eye lens dose with whole-body dose and KAP was assessed. RESULTS: DRF was 4.3/2.4 for wraparound glasses, 4.8/1.9 for fitover glasses, 9.1/6.8 for full-face visor in radial/femoral geometries. DRF of half-face visor depended on how it is worn (range 1.0-4.9). Statistically significant correlation between dose value over the PPE and chest dose was observed, while there was no correlation between eye lens dose and chest dose. The results on clinical staff showed statistically significant correlation between dose values over the PPE and KAP. CONCLUSIONS: All PPE showed significant DRF in all configurations, provided they were worn correctly. Single DRF value is not applicable to all clinical situations. KAP is a valuable tool for determining appropriate radiation protection measures.

Eye-Lens Dose Reduction using Region of Interest (ROI) Attenuators in Neuroimaging.

Lens dose can be high during neuro-interventional procedures, increasing the risk of cataractogenesis. Although beam collimation can be effective in reducing lens dose, it also restricts the FOV. ROI imaging with a reduced-dose peripheral field permits full-field information with reduced lens dose. This work investigates the magnitude of lens-dose reduction possible with ROI imaging. EGSnrc Monte-Carlo calculations of lens dose were made for the Zubal head phantom as a function of gantry angulation and head shift from isocenter for both large and small FOV's. The lens dose for ROI attenuators of varying transmission was simulated as the weighted sum of the lens dose from the small ROI FOV and that from the attenuated larger FOV. Image intensity and quantum mottle differences between ROI and periphery can be equalized by image processing. The lens dose varies considerably with beam angle, head shift, and field size. For both eyes, the lens-dose reduction with an ROI attenuator increases with LAO angulation, being highest for lateral projections and lowest for PA. For an attenuator with small ROI field (5 × 5 cm) and 20% transmission, the lens dose for lateral projections is reduced by about 75% compared to a full dose 10 ×10 cm FOV, while the reduction ranges between 30 and 40% for PA projections. Use of ROI attenuators can substantially reduce the dose to the lens of the eye for all gantry angles and head shifts, while allowing peripheral information to be seen in a larger FOV.

Measurement of Occupational Eye and Thyroid Radiation Doses in Pediatric Interventional Cardiologists at a Tertiary Hospital.

Background Advances in imaging techniques have led to increased utilization of imaging devices in catheterization laboratories. Invasive surgical procedures for cardiac disorders have been largely replaced by fluoroscopic cardiac catheterization. With this increase, concerns and risks associated with exposure to ionizing radiation among interventional cardiologists are growing. This study aims to measure and compare the occupational doses to the eye lens and thyroid of pediatric interventional cardiologists during different procedures in the catheterization laboratory and its significance. Methodology In this study, cardiologists wore bandanas with attached dosimeters to measure the absorbed doses to the eyes and thyroid gland. The dosimeters were collected for reading. The procedure types were also collected. In addition, the total fluoroscopy time and tube voltage of the biplane machine were measured. SPSS version 23 (IBM Corp., Armonk, NY, USA) was used to analyze the data. The characteristics of the study sample were described using simple counts and percentages, whereas means and standard deviations were used for continuous variables. Statistical significance was set at p-values <0.05. Results A total of 93 procedures were evaluated. The mean absorbed doses for all 93 procedures in both eyes and thyroid were 0.09 mGy and 0.08 mGy, respectively. A significant difference was found between the left and right eye measurements (p = 0.034), with higher doses administered to the left eye. However, no significant difference was observed between the right and left thyroid doses (p = 0.281). Significant correlations were found between the eye and thyroid doses and the procedure type (p = 0.02 and p = 0.009, respectively). Conclusions A significant amount of radiation was measured in the measurements of both organs. In addition, radiation dose measurements varied between different types of procedures. Our current results indicate the importance and necessity of applying the radiation protection concept of dose optimization.

[Radiation exposure of the eye lens in orthopedics and trauma surgery : A pilot study]. / Strahlenbelastung der Augenlinse in O&U : Eine Pilotstudie.

BACKGROUND: On 27 June 2017 the Act on new regulation of the law for the protection against the harmful effects of ionizing radiation was passed. One of the main innovations in daily surgical practice in the now legally stipulated provisions is the lowering of the eye lens dose to 20 mSv/year (§§ 78, 212 Radiation Protection Act, StrlSchG). MATERIAL AND METHODS: To estimate the level of exposure of the eye lens to ionizing radiation that is to be expected in the course of surgical interventions, the dose that surgeons receive during surgery was determined. For this, the radiation exposure adjacent to the eye lens was measured using a forehead dosimeter while performing surgical interventions over a period of 8 weeks in 2 different operating rooms. RESULTS: As a result, a mean estimated eye lens radiation dose Hp (3) of 190 µSv could be determined during the 2­month study period. Thus, the estimated cumulative radiation dose in 1 year of approximately 1.2 mSv was significantly below the threshold of 20 mSv/year. CONCLUSION: By complying with the common radiation protection measures in the context of operative interventions in orthopedics and trauma surgery, the legal limit value of 20 mSv/year is generally not expected to be exceeded.