Radiation exposure in augmented fluoroscopic bronchoscopy procedures: a comprehensive analysis for patients and physicians.

Cancer is a major health challenge and causes millions of deaths worldwide each year, and the incidence of lung cancer has increased. Augmented fluoroscopic bronchoscopy (AFB) procedures, which combine bronchoscopy and fluoroscopy, are crucial for diagnosing and treating lung cancer. However, fluoroscopy exposes patients and physicians to radiation, and therefore, the procedure requires careful monitoring. The National Council on Radiation Protection and Measurement and the International Commission on Radiological Protection have emphasised the importance of monitoring patient doses and ensuring occupational radiation safety. The present study evaluated radiation doses during AFB procedures, focusing on patient skin doses, the effective dose, and the personal dose equivalent to the eye lens for physicians. Skin doses were measured using thermoluminescent dosimeters. Peak skin doses were observed on the sides of the patients' arms, particularly on the side closest to the x-ray tube. Differences in the procedures and experience of physicians between the two hospitals involved in this study were investigated. AFB procedures were conducted more efficiently at Hospital A than at Hospital B, resulting in lower effective doses. Cone-beam computed tomography (CT) contributes significantly to patient effective doses because it has higher radiographic parameters. Despite their higher radiographic parameters, AFB procedures resulted in smaller skin doses than did image-guided interventional and CT fluoroscopy procedures. The effective doses differed between the two hospitals of this study due to workflow differences, with cone-beam CT playing a dominant role. No significant differences in left and right eyeHp(3) values were observed between the hospitals. For both hospitals, theHp(3) values were below the recommended limits, indicating that radiation monitoring may not be required for AFB procedures. This study provides insights into radiation exposure during AFB procedures, concerning radiation dosimetry, and safety for patients and physicians.

Occupational radiation exposure in anesthesia for hepatic chemoembolization: a prospective study

Introduction Anesthetists play an important role during interventional radiology procedures. Like the main operator, anesthetists may also be subject to significant radiation levels in the fluoroscopy suite. Due to its complexity, hepatic chemoembolization procedures demand high fluoroscopic times and digital subtraction angiography images, exposing patients and medical staff to high radiation doses. Objective To assess and quantify the radiation to which one anesthetist was exposed over the course of seven consecutive hepatic chemoembolization procedures, and compare it to the exposure received by the main operator. Methods Medical staff dosimetry was evaluated during seven consecutive hepatic chemoembolization procedures conducted in a private hospital in Recife (Brazil), using thermoluminiscent dosimeters placed in regions of the head and torso. Results For the seven procedures evaluated in this study, the anesthetist received, on average, absorbed doses to the glabella, left eyebrow, right eyebrow and effective dose of 142.4 ± 72 µSv, 117.3 ± 66 µSv, 137.8 ± 71 µSv and 12.4 ± 8.4 µSv, respectively. Conclusions In some cases, ocular dose and effective dose received by the anesthetist may be 4 and 4.7 times greater, respectively, when compared to the main operator. According to the results of this study, the current occupational annual dose limit to the lens of the eye of 20 mSv can be exceeded with only two hepatic chemoembolization procedures per week if adequate radiation protection conditions are not guaranteed.

Introducción El anestesiólogo desempeña un papel importante durante los procedimientos de radiología intervencionista. Al igual que el operador principal, el anestesiólogo también puede estar expuesto a niveles significativos de radiación en la sala de fluoroscopía. Debido a su complejidad, durante los procedimientos de quimioembolización hepática se deben utilizar imágenes de fluoroscopía y angiografía de sustracción digital por períodos prolongados, exponiendo a los pacientes y al personal médico a dosis elevadas de radiación. Objetivo Evaluar y cuantificar la radiación a la cual se expuso un anestesiólogo durante el transcurso de siete procedimientos consecutivos de quimioembolización hepática, y comparar con la exposición recibida por el operador principal. Métodos Evaluación de la dosimetría ocupacional durante siete procedimientos consecutivos de quimioembolización hepática realizados en un hospital privado de Recife (Brasil) por medio de dosímetros termoluminiscentes ubicados en regiones de la cabeza y el torso. Resultados Para los siete procedimientos evaluados en este estudio, el anestesiólogo recibió, en promedio, dosis absorbidas en el entrecejo, la ceja izquierda, la ceja derecha y dosis efectivas de 142,4 ± 72 µSv, 117,3 ± 66 µSv, 137,8 ± 71 µSv y 12,4 ± 8,4 µSv, respectivamente. Conclusiones En algunos casos, la dosis ocular y la dosis efectiva que recibe el anestesiólogo puede ser, respectivamente, entre 4 y 4,7 veces más alta que la que recibe el operador principal. De acuerdo con los resultados de este estudio, el límite ocupacional anual de dosis en cristalino (20 mSv) se puede superar con apenas dos procedimientos de quimioembolización hepática a la semana en caso de no garantizarse las condiciones adecuadas de protección contra la radiación.

Organ dose reconstruction for the radiation epidemiological study of Korean radiation workers: the first dose evaluation for the Korean Radiation Worker Study (KRWS).

The Korea Institute of Radiological and Medical Sciences has started a radiation epidemiological study, titled "Korean Radiation Worker Study," to evaluate the health effects of occupational exposure to radiation. As a part of this study, we investigated the methodologies and results of reconstructing organ-specific absorbed doses based on personal dose equivalent, Hp(10), reported from 1984 to 2019 for 20,605 Korean radiation workers. For the organ dose reconstruction, representative exposure scenarios (i.e., radiation energy and exposure geometry) were first determined according to occupational groups, and dose coefficients for converting Hp(10) to organ absorbed doses were then appropriately taken based on the exposure scenarios. Individual annual doses and individual cumulative doses were reconstructed for 27 organs, and the highest values were observed in the thyroid doses (on average 0.77 mGy/y and 10.47 mGy, respectively). Mean values of individual cumulative absorbed doses for the red bone marrow, colon, and lungs were 7.83, 8.78, and 8.43 mSv, respectively. Most of the organ doses were maximum for industrial radiographers, followed by nuclear power plant workers, medical workers, and other facility workers. The organ dose database established in this study will be utilized for organ-specific risk estimation in the Korean Radiation Worker Study.

Effectiveness of personal dose monitoring intercomparison results in a laboratory in Shanghai / 环境与职业医学

Background Individual monitoring of occupational external exposure is an essential part of the occupational health management of radiation workers, and is an important basis for the evaluation of individual absorbed dose and the diagnosis of occupational radiation diseases. Continuous participation of monitoring service providers in intercomparison is a fundamental quality assurance for routine monitoring, which can identify problems and improve them in time. Objective Taking the Laboratory of Radiation Protection in Shanghai Institute of Preventive Medicine as an example, to evaluate the performance of an individual occupational external dose monitoring system in the laboratory, identify influencing factors of the monitoring results, and provide a basis for improving the quality of daily monitoring by analyzing the process and results of a national intercomparison of individual dose monitoring. Methods According to the Testing criteria of personnel dosimetry performance for external exposure (GBZ 207-2016), and the relevant requirements of Class II (photon) inspection, a total of 20 groups of blind sample dosimeters were measured for four consecutive years from 2018 to 2021. The radiation energy source of each group was identified, and related personal dose equivalent Hp(10), the uncertainty of measurement results, and the deviation between the reported value and the reference value were calculated. The national intercomparison process and results of individual dose monitoring were also analyzed. Results The energy sources of the blind samples in the tested laboratory for four years were N100 or Cs-137. The reported dose values of the blind samples were 0.57-4.61 mSv, the combined uncertainties were 0.043-0.365 mSv, the expanded uncertainties (k=2) were 0.09-0.73 mSv, and the relative expanded uncertainties (k=2) were 13.8%-16.4%. The single-group performance ∣Pi∣ of 20 sets of blind samples in the four years was ≤0.10, the yearly comprehensive performance of 5 sets of blind samples was ≤0.10, and the yearly Q score of the test report was >15 points. The laboratory achieved excellent results in the national intercomparison of individual dose monitoring in four consecutive years, except the Q value not reaching full score. Conclusion The laboratory exhibits standardized data processing of individual dose monitoring, generates accurate and reliable results, and meets the requirements of relevant national standards; but it should continue to participate in the national intercomparison of individual dose monitoring, strengthen the angular response research of energy identified dosimeter, improve the monitoring ability of low-dose X-rays, analyze the key points of reducing the uncertainty of measurement results, and continuously improve the monitoring ability.

[Measurement as a Personal Dose Equivalent of X-ray Room Scattered Dose in ERCP Inspection].

PURPOSE: In the revised Regulation on Prevention of Ionizing Radiation Hazards (April 2020), the equivalent dose limit for the lens of the eye was lowered to "100 mSv in 5 years and 50 mSv in 1 year." It is necessary to reduce occupational exposure in the healthcare sector. The purpose of this study was to facilitate comparison with the equivalent dose limit in an endoscopic retrograde cholangiopancreatography (ERCP) examination by measuring the scattered dose in an X-ray room as an individual dose equivalent. METHODS: The scattered dose was measured by dosimeters positioned in a grid pattern in the X-ray room. The dose rate was measured with and without the use of a protective cloth (0.25 mm Pb equivalent) suspended around the X-ray tube extending to the patient. The dose reduction rate of the material was evaluated during the simulated ERCP. RESULTS: The maximum dose rate at the position of the surgeon performing an ERCP inspection in the standing position was 2.9 mSv/h (3 mm dose equivalent rate) at 150 cm from the ground. The number of ERCP examinations to comply with the equivalent dose limit of the equivalent dose of the lens of the eye without the protective cloth was 28 per year. CONCLUSION: The results of this study suggest that individual dose equivalent measurements in the X-ray clinic may facilitate comparison with the equivalent dose limit.

First Latin American and Caribbean interlaboratory comparison exercise for SSDLs on reference irradiation capabilities in personal dose equivalent.

A comparison exercise of Latin American and Caribbean Secondary Standards Dosimetry Laboratories (SSDLs) was jointly organized by the International Atomic Energy Agency (IAEA) and the Ionizing Radiation Metrology Laboratory at the Federal University of Pernambuco (LMRI-DEN/UFPE). This exercise was organized during an IAEA regional meeting on the review and update of calibration capabilities in Latin America, held in Recife, during the period from 23 to 27 April 2018 under the technical cooperation project ME-RLA 9085-170572. Fifteen participating SSDLs were required to irradiate optically stimulated personal dosimeters in terms of the personal dose equivalent Hp(10) in137Cs radiation quality. In addition, the IAEA Dosimetry Laboratory in Seibersdorf, Austria, and the National Physical Laboratory in Teddington, Middlesex, UK participated in this exercise as reference institutes. Each participant received 10 dosimeters that were hand-carried directly to the SSDL. Two nominal dose values of 2 mSv and 4 mSv were selected for this exercise. The participants irradiated the dosimeters using the setup and the procedures which are normally used in their standard laboratory for Hp(10) dosimeter irradiations. The dosimeters were evaluated as they were received by the coordinating laboratory, using a single BeOSL Reader. The results show that, except for one laboratory, the differences between the dosimeter reading and the assigned values were within 10%; this is consistent with the expanded uncertainty. The results indicate that most of the participant laboratories have a good capability to irradiate personal dosimeters in the quantity Hp(10).

Redox Status, Dose and Antioxidant Intake in Healthcare Workers Occupationally Exposed to Ionizing Radiation.

The purpose of this study was to evaluate the relationship between blood redox status, dose and antioxidant dietary intake of different hospital staff groups exposed to low doses of ionizing radiation (LDIR) (Interventional Radiology and Cardiology, Radiation Oncology, and Nuclear Medicine) and non-exposed. Personal dose equivalent (from last year and cumulative), plasma antioxidant markers (total antioxidant capacity, extracellular superoxide dismutase activity, and glutathione/oxidized glutathione ratio), oxidative stress markers (nitrites and nitrates, and lipid peroxidation) and dietary intake (antioxidant capacity using ORAC values) were collected and analyzed from 28 non-exposed healthcare workers and 42 healthcare workers exposed to LDIR. Hospital staff exposed to LDIR presented a redox imbalance in blood that seems to correlate with dose. Workers from the Nuclear Medicine Unit were the most affected group with the lowest value of plasma antioxidant response and the highest value of plasma thiobarbituric acid reactive substances, TBARS (indicator of lipid peroxidation) of all four groups. Cumulative personal dose equivalent positively correlated with nitrites and negatively correlated with total antioxidant capacity in blood. The diet of healthcare workers from Nuclear Medicine Unit had higher ORAC values than the diet of non-exposed. Therefore, occupational exposure to LDIR, especially for the Nuclear Medicine Unit, seems to produce an imbalanced redox status in blood that would correlate with cumulative personal dose equivalent.

Using Monte Carlo methods for Hp(0.07) values assessment during the handling of 18F-FDG.

The dose limit for the skin of the hand is typically converted to a surface of 1 cm2, which means that one needs to measure point doses in different places on the hand. However, the commonly used method of measuring doses on the hand, i.e., using a dosimetric ring including one or several thermoluminescent detectors worn at the base of a finger, is not adequate for manual procedures such as labeling or radiopharmaceutical injection. Consequently, the purpose of this study was to create and conduct a series of computer simulations that, by recreating the actual working conditions, would provide information on the values of ionizing radiation doses received by the most exposed parts of the hands of employees of radiopharmaceutical production facilities, as well as those of nurses during the injection of radiopharmaceuticals. The simulations were carried out using Monte Carlo radiation transport calculations. The Hp(0.07) personal dose equivalent values obtained for the fingertips of the index and middle fingers of nursing staff and chemists were within the range limited by the minimum and maximum Hp(0.07) values obtained as a result of dosimetric measurements carried out in diagnostic and production centers. Only in the case of the nurse's fingertip, the simulated value of Hp(0.07 slightly exceeded the measured maximum Hp(0.07) value. The comparison of measured and simulated dose values showed that the largest differences in Hp(0.07) values occurred at the thumb tip, and for ring finger and middle finger of some of the nurses investigated.

Calibration of the LiF - thermoluminescent detectors used for personal dose equivalent Hp(3) assessment.

AIMS: The issue of exposure of eye lenses of employees exposed to ionizing radiation is an interesting topic not only from the point of view of deterministic effects related to the occurrence of cataracts, but also dosimetric aspects, in particular the calibration of detectors in units enabling the assessment of eye lens exposure or personal dose equivalent Hp(3). The paper presents the idea of calibrating thermoluminescent detectors designed for the Hp(3) values measurement of gamma radiation, which the source is the process of annihilation of positrons emitted by the deoxyglucose marker - 18F radionuclide. METHODS: The method was based on the value of air kerma Ka to Hp(3) conversion coefficients (Hp(3,0°)/Ka) developed as part of the ORAMED project. High-sensitivity thermoluminescent detectors (MCP-N) produced in Poland were used in the measurements. During the exposure of the detectors, a 137Cs gamma radiation source (irradiator 137Cs/60Co) and a 20cm diameter cylinder filled with water were used. RESULTS & CONCLUSIONS: The value of conversion coefficient Hp(3,0°)/Ka for energy 511 keV is 1.31Sv/Gy and the calibration factor is (3.46±0.03)·10-4 mSv/N (N - number of counts). Verification of the value of the obtained coefficient carried out using a cylinder with a diameter of 20cm showed a difference of less than 2% in relation to the value obtained by the method described in this paper.

Air-kerma to Hp(0.07), Hp(3), and Hp(10) conversion coefficients for monoenergetic photons.

This work aims for calculating a new set of the personal dose equivalent conversion coefficients Hp(d)/Kair when d = 0.07, 3, and 10 mm, for monoenergetic photons beams ranged from 0.015 to 10 MeV, which have incident on ICRU slab phantom for Hp (0.07) and Hp (10) and cylindrical phantom for Hp (3). The new cylindrical phantom of the ORAMED project was proposed for calculating the eye lens dose equivalent as a cylinder much better approximates the form of a head than a slab. The calculations were carried out with MC and an analytical fit is applied to the data. Our results are found in a good agreement with those previously published, with a local difference less than 1.5%. We have concluded that new analytical fits provide a suitable method for determining conversion coefficients for discrete incident such as MC.

An analytical fit and EGSnrc code (MC) calculations of personal dose equivalent conversion coefficients for mono-energetic electrons.

This study aims for calculating a new set of the personal dose equivalent conversion coefficients Hp(d)/Φ when d = 0.07, 3, and 10 mm, for mono-energetic electron beams ranged from 0.06 MeV to 50 MeV for Hp(0.07), from 0.7 MeV to 50 MeV for Hp(3) and from 2 MeV to 50 MeV for Hp(10), which has incident on ICRU slab phantom. Additionally, we have calculated the conversion coefficients of a dose to the lens eye of into a new cylindrical phantom of the ORAMED project. The cylindrical phantom was proposed for calculating the eye lens dose equivalent as a cylinder much better approximates the form of a head than a slab. The ICRU tissue of density of 1 g/cm3 which is consists of 4-elemental has been used in slab and cylindrical phantoms. The calculations were carried out with EGSnrc code Monte Carlo (MC) and a new an analytical fit is applied to the data. Our results are found in a good agreement with those published by Veinot and Hertel (2012)) , with a local difference less than 1.5%. We have concluded that new analytical fits provide a convenient approach for determining conversion coefficients for discrete incident such as MC.

Effect of auxiliary radiological protective devices on reducing dose to the eye lens of interventional staff / 中华放射医学与防护杂志

Objective To establish a method for reducing the dose to the eye lens of interventional staff,and provide the data basis for improving radiological protection measures.Methods One piece of interventional equipment coupled with conventional auxiliary protective devices and two types of common neural interventional procedures were selected to monitor 46 and 35 procedures before and after the device modification.The doses to the eye lens of staff were measured with direct-reading dosimeters for analysis of dose trends.Results After modification of the devices,the average dose to the left eye lens decreased from (9.71 ±10.86) to (3.23 ±5.59) μSv for the first operator,from (9.51 ± 12.34) to (0.68 ± 0.78) μSv for the second in cerebral angiography;whereas the dose decreased from (14.83 ± 19.13) to (4.17±4.59) for the first operator and from (14.12±21.76) to (1.23 ±1.57)μSv for the second in embolization procedure,respectively.The left eye lens doses measured before and after the modification showed significant difference (U =-2.760,-2.467,-1.967,-2.655,P ＜0.05).Conclusions The modification of the auxiliary radiological protective devices may effectively reduce the dose to the eye lens dose.This method was shown to be feasible for the improvement of radiological protection of interventional staff.

Test and evaluation of performances of HARSHAW-3500 thermoluminescence dosimetry system / 医疗卫生装备

Objective To evaluate the reliability of HARSHAW-3500 thermoluminescence dosimetry system by testing its performances.Methods HARSHAW-3500 thermoluminescence dosimetry system had its performances tested and evaluated according to Verification regulation of thermoluminescence dosimetry systems used in persontal and environmental monitoring forXandgammaradiation(JJG 593-2006),Testingcriteriaofpersonneldosimetryperformanceforexternalexposure (GBZ 207-2016),Specifications for individual monitoring of occupational external exposure (GBZ 128-2016) and Thermoluminescence dosimetry systems for personal and environmental monitoring (GB/T 10264-2014),such as batch homogeneity,repeatability,linearity,incidence angle response,stability,energy response and scale factor,quantity inspection,residual dose,detection limit and etc.Results Testing results of various performance indicators proved to be within the limits according to national and industrial standards.Conclusion HARSHAW-3500 thermoluminescence dosimetry system conforms to the requirements for radiation dose measurement.It is beneficial to the improvement of quality and performance of thermoluminescence dosimetry by performances analysis and evaluation.

Effect of different annealing temperature on performance of thermoluminescent detector / 医疗卫生装备

Objective To improve the quality of personal dose equivalent measurement by exploring optimal annealing temperature conditions.Methods Totally 60 pieces of thermoluminescent detectors were randomly and equally divided into 6 groups.The 6 groups underwent 10-min annealing under 200,220,230,240,250 or 260 ℃ respectively,and then were cooled with the same conditions and went through measurement after irradiation by the calibrated radiation source.The above operation of annealing,cooling and measurement were repeated for 10 times,and the 6 groups were compared on dispersity,sensitivity and glow curve.Results Single test proved that under 240 ℃ the dispersity,sensitivity and glow curve gained optimal results comprehensively,while repeated tests showed that the dispersity had the optimal value under 250 ℃ and the sensitivity decreased significantly as the times of annealing rose.Conclusion Annealing conditions have to be selected according to the requirements of the thermoluminescent detector.

Test and evaluation of performances of HARSHAW-3500 thermoluminescence dosimetry system / 医疗卫生装备

Objective To evaluate the reliability of HARSHAW-3500 thermoluminescence dosimetry system by testing its performances.Methods HARSHAW-3500 thermoluminescence dosimetry system had its performances tested and evaluated according to Verification regulation of thermoluminescence dosimetry systems used in persontal and environmental monitoring forXandgammaradiation(JJG 593-2006),Testingcriteriaofpersonneldosimetryperformanceforexternalexposure (GBZ 207-2016),Specifications for individual monitoring of occupational external exposure (GBZ 128-2016) and Thermoluminescence dosimetry systems for personal and environmental monitoring (GB/T 10264-2014),such as batch homogeneity,repeatability,linearity,incidence angle response,stability,energy response and scale factor,quantity inspection,residual dose,detection limit and etc.Results Testing results of various performance indicators proved to be within the limits according to national and industrial standards.Conclusion HARSHAW-3500 thermoluminescence dosimetry system conforms to the requirements for radiation dose measurement.It is beneficial to the improvement of quality and performance of thermoluminescence dosimetry by performances analysis and evaluation.

Effect of different annealing temperature on performance of thermoluminescent detector / 医疗卫生装备

Objective To improve the quality of personal dose equivalent measurement by exploring optimal annealing temperature conditions.Methods Totally 60 pieces of thermoluminescent detectors were randomly and equally divided into 6 groups.The 6 groups underwent 10-min annealing under 200,220,230,240,250 or 260 ℃ respectively,and then were cooled with the same conditions and went through measurement after irradiation by the calibrated radiation source.The above operation of annealing,cooling and measurement were repeated for 10 times,and the 6 groups were compared on dispersity,sensitivity and glow curve.Results Single test proved that under 240 ℃ the dispersity,sensitivity and glow curve gained optimal results comprehensively,while repeated tests showed that the dispersity had the optimal value under 250 ℃ and the sensitivity decreased significantly as the times of annealing rose.Conclusion Annealing conditions have to be selected according to the requirements of the thermoluminescent detector.

X-ray spectra and doses.

Using the Monte Carlo method the x-ray spectrum produced by 150keV electrons colliding with W, Rh and Mo targets were calculated. The x-ray spectra were calculated to 20, 50, and 100cm from the focal point. In order to analyze the effect of the filter, calculations were carried out with and without filter. The spectra were used to estimate the Kerma in air, the Ambient dose equivalent, and the Personal dose equivalent. The spectra were integrated in energy to obtain the total photon fluences. Calculated spectra depend on the type of target having the continuous spectrum due to bremsstrahlung and the characteristics x-rays. The Al filter eliminates the low-energy photons; however no effect is noticed when the photon energy is larger than 40keV. The largest effect of dose reduction due to the filter was noticed to 20cm for the Kerma in air.

Reliability of eye lens dosimetry in workers of a positron emission tomography radiopharmaceutical production facility.

A new regulatory statement was issued concerning the eye lens radiation protection of persons in planned exposures. A debate was raised on the adequacy of the dosimetric quantity and on its method of measurement. The aim of this work was to establish the individual monitoring procedure with the EYE-D™ holder and a MCP-N LiF:Mg,Cu,P thermoluminescent chip detector for measuring the personal dose equivalent Hp(3) in workers of a Positron Emission Tomography Radiopharmaceutical Production Facility.

The measurements of eye lens dose for occupational staff in interventional procedures / 中华放射医学与防护杂志

Objective To establish methods of measuring the eye lens dose to interventional staff,to obtain relevant dose data and to provide a scientific basis for reducing eye lens dose.Methods Two kinds of dosimeters,thermoluminescent dosimeter (TLD) and optically stimulated luminescence dosimeter (OSLD),were selected to measure the personal dose equivalent HP (3) to eye lens of occupational staff in several kinds of interventional procedures,including cardiovascular interventional procedures,cerebrovascular interventional procedures etc.Five types of Digital Subtraction Angiography (DSA) equipment were chosen in the study,including single tube equipment and double tube equipment.Results The eye lens dose HP (3) to interventional staff varied significantly with different interventional procedures.The lowest dose is shown in the coronary angiography procedure,while the highest dose shown in the cerebral stenting procedure.For the same type of interventional procedure,the eye lens dose to the primary interventionist was the highest.For same interventionist,the dose to the left eye was obviously higher than that to the right eye.In addition,the measured results of OSLD were apparently higher than that of TLD.Conclusions Both TLD and OSLD could be used to measure eye lens dose,and the ways of calibrating TLD to evaluate personal dose equivalent HP (3) were feasible.The reason of significant difference between the measured results of TLD and OSLD needs further research.

Study of real-time measurements of occupational staff's eye lens doses by direct-reading dosimeters in interventional procedures / 中华放射医学与防护杂志

Objective To establish the methods for measuring the dose to occupational staff's eye lens in interventional procedures with direct-reading dosimeters,and to realize the real-time monitoring of eye lens dose and warning for high dose rate,thus providing the scientific basis of the staff radiological protection in interventional procedures.Methods Direct-reading dosimeters were calibrated with personal dose equivalent HP (3).The eye lens doses for occupational staff in different kinds of interventional procedures were measured by the devices with both single-and double X-ray tubes.The data obtained fromthe direct-reading dosimeters was compared to those obtained from TLDs.Results Direct-reading dosimeters showed good linear fitting with the calibration of HP (3),and the coefficients of variation were lower than 5％.The average eye lens HP (3) for the main operator in coronary arteriography and stent implantation in brain obtained by direct-reading dosimeters were 12.0 and 24.5 μSv,respectively,whereas those obtained by TLDs were 11.9 and 22.7 μSv,respectively.The direct-reading dosimeters gave similar t~nds as TLDs do so.The direct-reading dosimeters were able to provide eye lens HP (3) in each individual interventional procedure,and to monitor the real-time dose rate as well.Conclusions The calibration of HP (3) and the data gained by direct-reading dosimeters are reliable.Therefore,the methods for real-time measurement of eye lens dose for occupational staff in interventional procedures are successfully established.