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Kaljevic J, Stankovic K, Stankovic J, Ciraj-Bjelac O, Arandjic D. HAND DOSE EVALUATION OF OCCUPATIONALLY EXPOSED STAFF IN NUCLEAR MEDICINE. RADIATION PROTECTION DOSIMETRY 2016; 170:292-296. [PMID: 26656262 DOI: 10.1093/rpd/ncv500] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Manipulation of unsealed radiation sources in nuclear medicine (NM) departments involves non-uniform exposure to staff and high skin doses to the upper extremities from direct and scattered radiations. Conducted studies have shown that the annual dose limits could be exceeded and the continuous dose monitoring of NM worker's hands is needed. The aim of this article is to show results of hand dose monitoring in terms of operational quantity Hp(0.07) for occupationally exposed NM workers to beta and gamma radiations in the largest NM centre in Serbia. Dose assessment was done by means of thermoluminescent ring dosemeters DXT-RAD (LiF:Mg,Ti). Monthly and annual doses were evaluated for a 5-y period (2010-14). Monitored NM staff was categorised according to the type of work, as nurses, radiographers, laboratory technicians and radiochemists. Performed evaluation showed that annual hand doses were within the annual limit for all staff categories, but further optimisation of working practice is needed.
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Kaljevic J, Ciraj-Bjelac O, Stankovic J, Arandjic D, Bozovic P, Antic V. OCCUPATIONAL DOSE ASSESSMENT IN INTERVENTIONAL CARDIOLOGY IN SERBIA. RADIATION PROTECTION DOSIMETRY 2016; 170:279-283. [PMID: 26464526 DOI: 10.1093/rpd/ncv439] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The objective of this work is to assess the occupational dose in interventional cardiology in a large hospital in Belgrade, Serbia. A double-dosimetry method was applied for the estimation of whole-body dose, using thermoluminescent dosemeters, calibrated in terms of the personal dose equivalent Hp(10). Besides the double-dosimetry method, eye dose was also estimated by means of measuring ambient dose equivalent, H*(10), and doses per procedure were reported. Doses were assessed for 13 physicians, 6 nurses and 10 radiographers, for 2 consequent years. The maximum annual effective dose assessed was 4.3, 2.1 and 1.3 mSv for physicians, nurses and radiographers, respectively. The maximum doses recorded by the dosemeter worn at the collar level (over the apron) were 16.8, 11.9 and 4.5 mSv, respectively. This value was used for the eye lens dose assessment. Estimated doses are in accordance with or higher than annual dose limits for the occupational exposure.
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Pejovic SM, Pejovic MM, Stojanov D, Ciraj-Bjelac O. Sensitivity and fading of pMOS dosemeters irradiated with X-ray radiation doses from 1 to 100 cGy. RADIATION PROTECTION DOSIMETRY 2016; 168:33-39. [PMID: 25688061 DOI: 10.1093/rpd/ncv006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2014] [Accepted: 12/17/2014] [Indexed: 06/04/2023]
Abstract
In this paper, the results of pMOS dosemeters sensitivity to X-ray radiation and 28-d fading at room temperature are presented. Two types of dosemeters were used, which differ in gate oxide layer thickness. The sensitivity of pMOS dosemeters with gate oxide layer thickness of 1 µm was followed in the dose intervals of 1 to 10 cGy and 10 to 100 cGy, whereas that of 400 nm was in the interval of 10 to 100 cGy. The sensitivity was characterised by the threshold voltage shift, which was determined as a function of absorbed radiation dose and time after irradiation. Linear dependence between threshold voltage shift and absorbed radiation dose was established, as well as that considerable fading occurs during the first few days after irradiation. The mechanisms responsible for threshold voltage shift during irradiation and latter annealing have been also discussed.
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Dabin J, Negri A, Farah J, Ciraj-Bjelac O, Clairand I, De Angelis C, Domienik J, Jarvinen H, Kopec R, Majer M, Malchair F, Novák L, Siiskonen T, Vanhavere F, Trianni A, Knežević Ž. Characterisation of grids of point detectors in maximum skin dose measurement in fluoroscopically-guided interventional procedures. Phys Med 2015; 31:1112-1117. [DOI: 10.1016/j.ejmp.2015.08.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 08/26/2015] [Accepted: 08/28/2015] [Indexed: 10/22/2022] Open
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Hourdakis CJ, Büermann L, Ciraj-Bjelac O, Csete I, Delis H, Gomola I, Persson L, Novak L, Petkov I, Toroi P. Comparison of pencil-type ionization chamber calibration results and methods between dosimetry laboratories. Phys Med 2015; 32:42-51. [PMID: 26508013 DOI: 10.1016/j.ejmp.2015.09.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Revised: 09/09/2015] [Accepted: 09/12/2015] [Indexed: 11/20/2022] Open
Abstract
A comparison of calibration results and procedures in terms of air kerma length product, PKL, and air kerma, K, was conducted between eight dosimetry laboratories. A pencil-type ionization chamber (IC), generally used for computed tomography dose measurements, was calibrated according to three calibration methods, while its residual signal and other characteristics (sensitivity profile, active length) were assessed. The results showed that the "partial irradiation method" is the preferred method for the pencil-type IC calibration in terms of PKL and it could be applied by the calibration laboratories successfully. Most of the participating laboratories achieved high level of agreement (>99%) for both dosimetry quantities (PKL and K). Estimated relative standard uncertainties of comparison results vary among laboratories from 0.34% to 2.32% depending on the quantity, beam quality and calibration method applied. Detailed analysis of the assigned uncertainties have been presented and discussed.
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Ciraj-Bjelac O, Gavrilovic M, Arandjic D, Vujovic M, Bozovic P. Radiation exposure during X-ray examinations in a large paediatric hospital in Serbia. RADIATION PROTECTION DOSIMETRY 2015; 165:220-225. [PMID: 25821208 DOI: 10.1093/rpd/ncv084] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Objective of this work is to evaluate radiation exposure from X-ray examinations in a large paediatric hospital in Serbia, including radiographic, fluoroscopic and computed tomography (CT) examinations in four age groups: 0-1, 1-5, 5-10 and 10-15 y. Incident air kerma was assessed for the following radiographies: chest (AP, PA, LAT), spine (AP, LAT), pelvis (AP), urinary tract (AP, PA) and skull (AP, PA, LAT). Kerma-area product was measured for the fluoroscopy examinations: barium swallow, barium meal, barium enema and micturating cystography. Dose in CT was assessed in terms of volume CT dose index and dose-length product for examinations of the head, chest and abdomen. The collected data were compared with other similar studies, which indicated a need to expand such survey to other paediatric hospitals in Serbia.
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Farah J, Trianni A, Ciraj-Bjelac O, Clairand I, De Angelis C, Delle Canne S, Hadid L, Huet C, Jarvinen H, Negri A, Novák L, Pinto M, Siiskonen T, Waryn MJ, Knežević Ž. Characterization of XR-RV3 GafChromic®
films in standard laboratory and in clinical conditions and means to evaluate uncertainties and reduce errors. Med Phys 2015; 42:4211-26. [DOI: 10.1118/1.4922132] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Farah J, Trianni A, Carinou E, Ciraj-Bjelac O, Clairand I, Dabin J, De Angelis C, Domienik J, Jarvinen H, Kopec R, Majer M, Malchair F, Negri A, Novák L, Siiskonen T, Vanhavere F, Knežević Ž. Measurement of maximum skin dose in interventional radiology and cardiology and challenges in the set-up of European alert thresholds. RADIATION PROTECTION DOSIMETRY 2015; 164:138-142. [PMID: 25316909 DOI: 10.1093/rpd/ncu314] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
To help operators acknowledge patient dose during interventional procedures, EURADOS WG-12 focused on measuring patient skin dose using XR-RV3 gafchromic films, thermoluminescent detector (TLD) pellets or 2D TL foils and on investigating possible correlation to the on-line dose indicators such as fluoroscopy time, Kerma-area product (KAP) and cumulative air Kerma at reference point (CK). The study aims at defining non-centre-specific European alert thresholds for skin dose in three interventional procedures: chemoembolization of the liver (CE), neuroembolization (NE) and percutaneous coronary interventions (PCI). Skin dose values of >3 Gy (ICRP threshold for skin injuries) were indeed measured in these procedures confirming the need for dose indicators that correlate with maximum skin dose (MSD). However, although MSD showed fairly good correlation with KAP and CK, several limitations were identified challenging the set-up of non-centre-specific European alert thresholds. This paper presents preliminary results of this wide European measurement campaign and focuses on the main challenges in the definition of European alert thresholds.
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Ciraj-Bjelac O, Rehani MM. Eye dosimetry in interventional radiology and cardiology: current challenges and practical considerations. RADIATION PROTECTION DOSIMETRY 2014; 162:329-337. [PMID: 24262928 DOI: 10.1093/rpd/nct291] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Interventional radiology and cardiology are areas with high potential for risk to eye lens. Accurate assessment of eye dose is one of the most important aspects of correlating doses with observed lens opacities among workers in interventional suites and ascertaining compliance with regulatory limits. The purpose of this paper is to review current approaches and opportunities in eye dosimetry and assess challenges in particular in accuracy and practicality. The possible approaches include practical dosimetry using passive dosemeters or active dosemeters with obvious advantage of active dosimetry. When neither of these is available, other approaches are based on either retrospective dose assessment using scatter radiation dose levels or correlations between patient dose indices and eye doses to the operators. In spite of all uncertainties and variations, estimation of eye dose from patient dose can be accepted as a compromise. Future challenges include development of practical methods for regular monitoring of individual eye doses and development of better techniques to estimate eye dose from measurements at some reference points.
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Antic V, Ciraj-Bjelac O, Stankovic J, Arandjic D, Todorovic N, Lucic S. Radiation exposure to nuclear medicine staff involved in PET/CT practice in Serbia. RADIATION PROTECTION DOSIMETRY 2014; 162:577-585. [PMID: 24464817 DOI: 10.1093/rpd/ncu001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The purpose of this work is to evaluate the radiation exposure to nuclear medicine (NM) staff in the two positron emission tomography-computed tomography centres in Serbia and to investigate the possibilities for dose reduction. Dose levels in terms of Hp(10) for whole body and Hp(0.07) for hands of NM staff were assessed using thermoluminescence and electronic personal dosemeters. The assessed doses per procedure in terms of Hp(10) were 4.2-7 and 5-6 μSv, in two centres, respectively, whereas the extremity doses in terms of Hp(0.07) in one of the centres was 34-126 μSv procedure(-1). The whole-body doses per unit activity were 17-19 and 21-26 μSv GBq(-1) in two centres, respectively, and the normalised finger dose in one centre was 170-680 μSv GBq(-1). The maximal estimated annual whole-body doses in two centres were 3.4 and 2.0 mSv, while the corresponding extremity dose in the later one was 45 mSv. Improvements as introduction of automatic dispensing system and injection and optimisation of working practice resulted in dose reduction ranging from 12 up to 67 %.
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Ceklic S, Arandjic D, Zivanovic M, Ciraj-Bjelac O, Lazarevic D. Performance of radiation survey meters in X- and gamma-radiation fields. RADIATION PROTECTION DOSIMETRY 2014; 162:139-143. [PMID: 25063785 DOI: 10.1093/rpd/ncu246] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The aim of this work was to investigate the different types of radiation detectors commonly used for radiation protection purposes as survey meters. The study was performed on survey meters that use different detectors as ionisation chamber, Geiger Mueller (GM) counter and scintillation detector. For each survey meter, energy dependence and angular response in X- and gamma-radiation fields was tested. The following commercially available survey meters were investigated: ionisation chambers Victoreen 451P, Babyline 31 and VA-J-15A, Geiger counter MRK-M87, 6150 AD6 and FAG FH 40F2 and scintillation counter 6150 ADB. As a source of gamma radiation, (137)Cs and (60)Co were used whereas X-ray radiation fields were generated using an X-ray unit. The radiation characteristics of the survey meters were mostly in compliance with references estimated by standard IEC 1017-2. However, some of them showed larger deviation at lower energies. GM counters exhibit strong energy dependence for low-energy photons.
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Arandjic D, Ciraj-Bjelac O, Hadnadjev D, Stojanovic S, Bozovic P, Ceklic S, Lazarevic D. Radiation doses in adult computed tomography practice in Serbia: initial results. RADIATION PROTECTION DOSIMETRY 2014; 162:135-138. [PMID: 25063787 DOI: 10.1093/rpd/ncu245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
This work presents initial data on radiation doses in adult computed tomography (CT) in Serbia. Data were collected in terms of CT dose index (CTDIvol) and dose length product (DLP) values for head, chest and abdomen examination. The range of CTDIvol values was found to be 53-98, 11-34 and 8.5-227 mGy whereas for DLP was 803-1066, 350-845 and 1066-3078 mGy cm(-1) for head, chest and abdomen examination, respectively. Except for abdomen on one CT unit, all estimated values were in line with the reported data. This work also presents simple method on how to reduce radiation doses when scanning head. Using axial (step-and-shot) instead of helical mode and decreasing tube current-time product leads to significant dose reduction. CTDIvol was decreased by 20 % whereas DLP was reduced for a factor 2.
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Pejovic S, Bosnjakovic P, Ciraj-Bjelac O, Pejovic MM. Characteristics of a pMOSFET suitable for use in radiotherapy. Appl Radiat Isot 2013; 77:44-9. [DOI: 10.1016/j.apradiso.2013.02.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2012] [Revised: 01/30/2013] [Accepted: 02/19/2013] [Indexed: 10/27/2022]
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Arandjic D, Bonutti F, Biasizzo E, Ciraj-Bjelac O, Floreani M, Giustizieri M, Iaiza F, Inkoom S, Tommasini G, Padovani R. Radiation doses in cerebral perfusion computed tomography: patient and phantom study. RADIATION PROTECTION DOSIMETRY 2013; 154:459-464. [PMID: 23060430 DOI: 10.1093/rpd/ncs260] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The purpose of this study was to investigate radiation doses in cerebral perfusion computed tomography (CT) examination. As a part of routine patient monitoring, data were collected on patients in terms of the skin dose and CT dose index (CTDIvol) and dose-length product (DLP) values. For the estimation of the dose to the lens a phantom study was performed. Dose values for skin and lens were below the threshold for deterministic effects. The results were also compared with already published data. For better comparison, the effective dose was also estimated. The values collected on patients were in the ranges 230-680 mGy for CTDI and 2120-2740 mGy cm for DLP, while the skin dose and estimated effective dose were 340-800 mGy and 4.9-6.3 mSv, respectively. These values measured in the phantom study were similar, while the doses estimated to the lens were 53 and 51 mGy for the right and left lens, respectively.
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Antic V, Ciraj-Bjelac O, Rehani M, Aleksandric S, Arandjic D, Ostojic M. Eye lens dosimetry in interventional cardiology: results of staff dose measurements and link to patient dose levels. RADIATION PROTECTION DOSIMETRY 2012; 154:276-284. [PMID: 23152146 DOI: 10.1093/rpd/ncs236] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Workers involved in interventional cardiology procedures receive high eye lens dose if protection is not used. Currently, there is no suitable method for routine use for the measurement of eye dose. Since most angiography machines are equipped with suitable patient dosemeters, deriving factors linking staff eye doses to the patient doses can be helpful. In this study the patient kerma-area product, cumulative dose at an interventional reference point and eye dose in terms of Hp(3) of the cardiologists, nurses and radiographers for interventional cardiology procedures have been measured. Correlations between the patient dose and the staff eye dose were obtained. The mean eye dose was 121 µSv for the first operator, 33 µSv for the second operator/nurse and 12 µSv for radiographer. Normalised eye lens doses per unit kerma-area product were 0.94 µSv Gy⁻¹ cm⁻² for the first operator, 0.33 µSv Gy⁻¹ cm⁻² for the second operator/nurse and 0.16 µSv Gy⁻¹ cm⁻² for radiographers. Statistical analysis indicated that there is a weak but significant (p < 0.01) correlation between the eye dose and the kerma-area product for all three staff categories. These values are based on a local practice and may provide useful reference for other studies for validation and for wider utilisation in assessing the eye dose using patient dose values.
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Ciraj-Bjelac O, Rehani M, Minamoto A, Sim KH, Liew HB, Vano E. Radiation-induced eye lens changes and risk for cataract in interventional cardiology. Cardiology 2012; 123:168-71. [PMID: 23128776 DOI: 10.1159/000342458] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2012] [Accepted: 08/01/2012] [Indexed: 11/19/2022]
Abstract
BACKGROUND Recent studies have reported a significant increase in eye lens opacities among staff in the cardiac catheterization laboratory but indicated further studies are needed to confirm the findings. OBJECTIVE To evaluate the prevalence of opacities in eyes of cardiologists, radiographers and nurses working in interventional cardiology. METHODS The eyes of 52 staff in interventional cardiology facilities and 34 age- and sex-matched unexposed controls were screened in a cardiology conference held in Kuala Lumpur by dilated slit-lamp examination, and posterior lens changes were graded. Individual cumulative lens X-ray exposures were calculated from responses to a questionnaire in terms of workload and working practice. RESULTS The prevalence of posterior lens opacities among interventional cardiologists was 53%, while in nurses and radiographers it was 45%. Corresponding relative risks were 2.6 (95% CI: 1.2-5.4) and 2.2 (95% CI: 0.98-4.9), for interventional cardiologists and support staff, respectively. CONCLUSIONS This study confirms a statistically significant increase in radiation-associated posterior lens changes in the eyes of interventional cardiology staff.
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Rehani MM, Ciraj-Bjelac O, Vañó E, Miller DL, Walsh S, Giordano BD, Persliden J. ICRP Publication 117. Radiological protection in fluoroscopically guided procedures performed outside the imaging department. Ann ICRP 2012; 40:1-102. [PMID: 22732420 DOI: 10.1016/j.icrp.2012.03.001] [Citation(s) in RCA: 162] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An increasing number of medical specialists are using fluoroscopy outside imaging departments, but there has been general neglect of radiological protection coverage of fluoroscopy machines used outside imaging departments. Lack of radiological protection training of those working with fluoroscopy outside imaging departments can increase the radiation risk to workers and patients. Procedures such as endovascular aneurysm repair, renal angioplasty, iliac angioplasty, ureteric stent placement, therapeutic endoscopic retrograde cholangio-pancreatography,and bile duct stenting and drainage have the potential to impart skin doses exceeding Gy. Although tissue reactions among patients and workers from fluoroscopy procedures have, to date, only been reported in interventional radiology and cardiology,the level of fluoroscopy use outside imaging departments creates potential for such injuries.A brief account of the health effects of ionising radiation and protection principles is presented in Section 2. Section 3 deals with general aspects of the protection of workers and patients that are common to all, whereas specific aspects are covered in Section 4 for vascular surgery, urology, orthopaedic surgery, obstetrics and gynaecology,gastroenterology and hepatobiliary system, and anaesthetics and pain management.Although sentinel lymph node biopsy involves the use of radio-isotopic methods rather than fluoroscopy, performance of this procedure in operating theatres is covered in this report as it is unlikely that this topic will be addressed in another ICRP publication in coming years. Information on radiation dose levels to patients and workers, and dose management is presented for each speciality.
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Rehani MM, Ciraj-Bjelac O, Al-Naemi HM, Al-Suwaidi JS, El-Nachef L, Khosravi HR, Kharita MH, Muthuvelu P, Pallewatte AS, Juan BCS, Shaaban M, Zaman A. Radiation protection of patients in diagnostic and interventional radiology in Asian countries: Impact of an IAEA project. Eur J Radiol 2012; 81:e982-9. [DOI: 10.1016/j.ejrad.2012.06.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2012] [Revised: 03/12/2012] [Accepted: 06/20/2012] [Indexed: 10/28/2022]
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Milatović A, Ciraj-Bjelac O, Ivanović S, Jovanović S, Spasić-Jokić V. Patient dose measurements in diagnostic radiology procedures in Montenegro. RADIATION PROTECTION DOSIMETRY 2012; 149:454-463. [PMID: 21775317 DOI: 10.1093/rpd/ncr317] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
It was the aim of the study presented here to estimate for the first time patient dose levels in conventional diagnostic radiology in Montenegro. Measurements of patient dose in terms of entrance surface air kerma (ESAK) and kerma-area product (KAP) were performed on at least 10 patients for each examination type, in each of five randomly selected health institutions in Montenegro, so that a total of 872 patients for 16 different examination categories were included in the survey (817 patients for 1049 radiographies and 55 fluoroscopy patients). Exposure settings and individual data were recorded for each patient. Mean, median and third quartile values ESAK of patient doses are reported. The estimated mean ESAK values obtained are as follows: 4.7 mGy for pelvis anteroposterior (AP), 4.5 mGy for lumbar spine AP, 7.8 mGy for lumbar spine lateral (LAT), 3.1 mGy for thoracic spine AP and 4.3 mGy for thoracic spine LAT. When compared with the European diagnostic reference values, the mean ESAK for all studied examination types are found to be below the reference levels, except in chest radiography. Mean ESAK values for chest radiography are 0.9 mGy for posteroanterior (PA) projection and 2.0 mGy for LAT. The results exhibit a wide range of variation. For fluoroscopy examinations, the total KAP was measured. The mean KAP value per procedure for barium meal is found to be 22 Gy cm(2), 41 Gy cm(2) for barium enema and 19 Gy cm(2) for intravenous urography. Broad dose ranges for the same types of examinations indicate the necessity of applying practice optimisation in diagnostic radiology and establishment of national diagnostic reference levels.
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Krmar M, Baucal M, Bozic N, Jovancevic N, Ciraj-Bjelac O. Neutron dose equivalent measured at the maze door with various openings for the jaws and MLC. Med Phys 2012; 39:1278-81. [PMID: 22380359 DOI: 10.1118/1.3682313] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE This study was undertaken to explore the effects of the jaws and the MLC openings on the neutron dose equivalent (DE) at the maze door and neutron flux at the patient plane. METHODS The neutron dose equivalent was measured at the maze entrance door of a 15 MV therapy linear accelerator room. All measurements were performed using various field sizes up to 40 cm × 40 cm. Activation detectors constructed from natural Indium (In) were exposed at Cd envelope to neutrons in order to estimate relative changes of epithermal neutron fluences in the patient plane. RESULTS Our study showed that the dose equivalent at the maze door is at the highest when the jaw are closed and that maximal jaws opening reduces the DE by more than 20%. The neutron dose equivalent at the maze door measured for radiation fields defined by jaws do not differ significantly from the DE measured when MLC determines the same size radiation field. The epithermal capture reaction rate measured using different jaw openings differs by approximately 10%. When an MLC leaf is inserted into a fixed geometry for one opening of the jaws, an increase of the epithermal neutron capture reaction rate in Indium activation detectors was observed. CONCLUSIONS There is no significant difference in the neutron DE when MLC defines radiation field instead of jaws. This leads to the conclusion that the overall number of neutrons remains similar and it does not depend on how primary photon beam was stopped-by the jaws or the MLC. An increase of the fast neutron capture reaction rate when MLC leaves are inserted probably originates from the neutron scattering.
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Ciraj-Bjelac O, Beganović A, Faj D, Ivanovic S, Videnovic I, Rehani M. Status of radiation protection in interventional cardiology in four East European countries. RADIATION PROTECTION DOSIMETRY 2011; 147:62-67. [PMID: 21725081 DOI: 10.1093/rpd/ncr268] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Level of staff and patient radiation protection in interventional cardiology in four counties (Bosnia and Herzegovina, Croatia, Montenegro and Serbia) as a part of International Atomic Energy Agency project (RER/9/093) are presented. Patient doses were assessed in terms of air kerma area product (KAP), peak skin dose (PSD) or air kerma at interventional reference point (K(IRP)). Results were available from nine hospitals: 775 patients for KAP, 157 for PSD and 437 for K(IRP). Eight centres reported KAP >100 Gy cm(2) and five centres reported values >200 Gy cm(2). From patients monitored in terms of PSD, 14 (9 %) had PSD >2 Gy and 6 (3 %) patients from those monitored in terms of K(IRP) had value >5 Gy, indicating risk of skin injury. The results indicate need for optimisation and dose monitoring in complex fluoroscopically guided cardiology interventions.
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Rehani MM, Vano E, Ciraj-Bjelac O, Kleiman NJ. Radiation and cataract. RADIATION PROTECTION DOSIMETRY 2011; 147:300-304. [PMID: 21764807 DOI: 10.1093/rpd/ncr299] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
When this paper was about to go to press, the International Commission on Radiological Protection released a statement recommending a change in the threshold dose for the eye lens and dose limits for eye for occupationally exposed persons. It is clear that the earlier published threshold for radiation cataract is no longer valid. Epidemiological studies among Chernobyl clean-up workers, A bomb survivors, astronauts, residents of contaminated buildings, radiological technicians and recent surveys of staff in interventional rooms indicate that there is an increased incidence of lens opacities at doses below 1 Gy. Nevertheless, eye lens dosimetry is at a primitive stage and needs to be developed further. Despite uncertainties concerning dose threshold and dosimetry, it is possible to significantly reduce the risk of radiation cataract through the use of appropriate eye protection. By increasing awareness among those at risk and better adoption and increased usage of protective measures, radiation cataract can become preventable despite lowering of dose limits.
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Ciraj-Bjelac O, Arandjic D, Kosutic D. Comparison of different methods for shielding design in computed tomography. RADIATION PROTECTION DOSIMETRY 2011; 147:133-136. [PMID: 21743070 DOI: 10.1093/rpd/ncr287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The purpose of this work is to compare different methods for shielding calculation in computed tomography (CT). The BIR-IPEM (British Institute of Radiology and Institute of Physics in Engineering in Medicine) and NCRP (National Council on Radiation Protection) method were used for shielding thickness calculation. Scattered dose levels and calculated barrier thickness were also compared with those obtained by scatter dose measurements in the vicinity of a dedicated CT unit. Minimal requirement for protective barriers based on BIR-IPEM method ranged between 1.1 and 1.4 mm of lead demonstrating underestimation of up to 20 % and overestimation of up to 30 % when compared with thicknesses based on measured dose levels. For NCRP method, calculated thicknesses were 33 % higher (27-42 %). BIR-IPEM methodology-based results were comparable with values based on scattered dose measurements, while results obtained using NCRP methodology demonstrated an overestimation of the minimal required barrier thickness.
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Ciraj-Bjelac O, Beganovic A, Faj D, Gershan V, Ivanovic S, Videnovic IR, Rehani MM. Radiation protection of patients in diagnostic radiology: Status of practice in five Eastern-European countries, based on IAEA project. Eur J Radiol 2011; 79:e70-3. [DOI: 10.1016/j.ejrad.2011.03.075] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2010] [Revised: 03/16/2011] [Accepted: 03/23/2011] [Indexed: 10/18/2022]
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Ciraj-Bjelac O, Avramova-Cholakova S, Beganovic A, Economides S, Faj D, Gershan V, Grupetta E, Kharita MH, Milakovic M, Milu C, Muhogora WE, Muthuvelu P, Oola S, Setayeshi S, Schandorf C, Ursulean I, Videnovic IR, Zaman A, Ziliukas J, Rehani MM. Image quality and dose in mammography in 17 countries in Africa, Asia and Eastern Europe: results from IAEA projects. Eur J Radiol 2011; 81:2161-8. [PMID: 21665395 DOI: 10.1016/j.ejrad.2011.05.026] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2010] [Revised: 05/13/2011] [Accepted: 05/19/2011] [Indexed: 11/25/2022]
Abstract
PURPOSE The objective is to study mammography practice from an optimisation point of view by assessing the impact of simple and immediately implementable corrective actions on image quality. MATERIALS AND METHODS This prospective multinational study included 54 mammography units in 17 countries. More than 21,000 mammography images were evaluated using a three-level image quality scoring system. Following initial assessment, appropriate corrective actions were implemented and image quality was re-assessed in 24 units. RESULTS The fraction of images that were considered acceptable without any remark in the first phase (before the implementation of corrective actions) was 70% and 75% for cranio-caudal and medio-lateral oblique projections, respectively. The main causes for poor image quality before corrective actions were related to film processing, damaged or scratched image receptors, or film-screen combinations that are not spectrally matched, inappropriate radiographic techniques and lack of training. Average glandular dose to a standard breast was 1.5 mGy (mean and range 0.59-3.2 mGy). After optimisation the frequency of poor quality images decreased, but the relative contributions of the various causes remained similar. Image quality improvements following appropriate corrective actions were up to 50 percentage points in some facilities. CONCLUSIONS Poor image quality is a major source of unnecessary radiation dose to the breast. An increased awareness of good quality mammograms is of particular importance for countries that are moving towards introduction of population-based screening programmes. The study demonstrated how simple and low-cost measures can be a valuable tool in improving of image quality in mammography.
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