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Radiation dose in endoscopic retrograde cholangiopancreatography: Does the operator experience really matter?
Abstracts / Physica Medica 30 (2014) e45ee74
the 20 mSv/y as a dose limit for radiation workers. It has been previously indicated that the risk of low birth weight (LBW) is enhanced due to maternal medical exposures during pregnancy Objectives: The main aim of this study was to find out whether there is a relationship between long term exposure to background radiation levels above the normal amount and the risk of low birth weight. Materials and methods: A cross-sectional study was conducted in high background radiation areas (HBRAs) of Ramsar and neighboring areas with normal levels of background radiation (NBRAs). An interview was conducted using a questionnaire administered to 320 women from HBRAs and 280 women from NBRAs by an expert radiation biologist. Screening and stratified random sampling were used for selection of the subjects (vaginal or caesarian). Results: The mean birth weight of the newborns to mothers from HBRAs was 2820.3 ± 654.2 g. and that of the newborns to the mothers from NBRAs was 2925.2 ± 543.2 g. The difference between the mean weight of the newborns of the mothers from HBRAs and NBRAs was statistically significant (P¼0.034). Conclusions: In this study, it was revealed that the birth weight may be associated with the level of background radiation in the mothers’ living area before and during pregnancy. However, the results of the present study question the reports given by previous studies revealing that pregnant mothers exposure to ionizing radiation enhanced the occurrence of low birth weight. Keywords: Ionizing radiation, Non-ionizing radiation, Pregnancy, Low birth weight, Term labor RADIATION DOSE IN ENDOSCOPIC RETROGRADE CHOLANGIOPANCREATOGRAPHY: DOES THE OPERATOR EXPERIENCE REALLY MATTER? V. Tsapaki a, K. Paraskeva a, A. Giannakopoulos a, S. Papasavvas a, N. Mathou a, P. Aggelogiannopoulou a, S. Triantopoulou a, H. Al Malki a, I. Tsalafoutas b, Ch. Triantopoulou a, J.A. Karagiannis a. a Konstantopoulio General Hospital of Nea Ionia, Athens, Greece; b “Agios Savvas” General Hospital, Athens, Greece Background: Endoscopic retrograde cholangiopancreatography (ERCP) is the gold standard technique for treating the disorders of the billiary and pancreatic ducts . During ERCP, a side viewing endoscope passes through the mouth, esophagus and stomach into the duodenum and the papilla of Vater is cannulated using fluoroscopy as a guidance. During fluoroscopic guidance, the position of the endoscope and its relationship within the duodenum is .verified in real time. Therefore, extensive use of X-ray fluoroscopy and a large number of radiographs are possible. It is also a highly technical and complex technique that greatly depends on the endoscopist’s experience. The quality and success of ERCP as well as limitation of various clinical complications depend on the training of the endoscopist. The aim of the study was to compare patient’s radiation exposure during ERCP, in relation to the endoscopist’s experience. Materials and methods: All ERCPs were performed using a conventional radiology X-ray machine (Philips Essenta) with a Kerma Area Product (KAP) meter installed in the X-ray tube.. The meter was calibrated according to the method summarized in the ‘national protocol for patient dose measurements in diagnostic radiology’ developed by the National Radiological Protection Board (NRPB). In each ERCP, KAP in Gycm2, fluoroscopy time (FT) in min and total number of X-ray films (F) were recorded . All ERCP procedures were done under sedation and with a fixed set-up for the patient. The X-ray system was controlled by the radiographer according to endoscopist’s instructions. The ERCPs were performed by a high volume endoscopist ( HVE) (more than 200 ERCP/year for 10 years) and a low volume endoscopist (LVE) in its first year after finishing basic ERCP training Results: A total number of 239 patients were included in the study, 56 of which were performed by LVE and 183 by HVE. Median KAP was significantly lower for the patients done by the HVE ( 11,42 Gy.cm2 (range: 0,81-175,93 Gy.cm2) vs 23,14 Gy.cm2 (range: 1,20-198,02 Gy.cm2).
e57
Similarly, FT was shorter for the HVE (Median T: 3,5 min) versus LVE (Median T: 2,3 min). For both operators, radiation dose was correlated with number of films taken (f), (LVE): 0,59 and HVE: 0,64. Conclusion: Our study shows that ERCP patient radiation dose is significantly higher for a low volume cases endoscopist. It is therefore essential to draw the attention of the ERCP practitioners, especially the beginners, to the radiation their patients receive compared to high volume endoscopists. COMPARISON OF ENTRANCE SURFACE DOSE OF FOUR ROUTINE CT EXAMINATIONS: HELICAL SCAN VERSUS WIDE VOLUME SCAN MODES Ying-Lan Liao a, Yan-Shi Chen b, Hui-Yu Tsai b, c, d. a Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu 300, Taiwan; b Department of Medical Imaging and Radiological Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan; c Institute for Radiological Research, Chang Gung University / Chang Gung Memorial Hospital, Taoyuan 333, Taiwan; d Healthy Aging Research Center, Chang Gung University, Taoyuan 333, Taiwan Background: Computed tomography (CT) plays an important role in diagnostic radiology for radiologists because of excellent image quality within a very short acquisition time. A 320-detector row CT scanner has a collimation width up to 160 mm and a specific scan mode called wide volume scan mode based on axial scan mode was developed. The total scan length of a patient is adjusted automatically into several scan ranges equally. Then the patient will be scanned like a step and shoot procedure to acquire the imaging data. However, the mechanism of the wide volume scan mode together with the automatic tube current modulation (ATCM) technique remains unclear. The purpose of our study was to assess the surface dose distribution during wide volume scan mode of four adult CT examinations and compare it with those of helical scan modes. Materials and methods: An averaged-sized anthropomorphic phantom was scanned with four adult CT examinations (head, chest, abdomen, and chest-abdomen-pelvis (CAP)) of a 320 detector-row CT scanner (Aquilion ONE, Toshiba, Japan) (Table 1). The ATCM technique (SureExposure 3D, Toshiba, Japan) was used during the wide volume scan mode and helical scan mode. The radiochromic film strips (Gafchromic XR-QA2, ISP, USA) were used to measure the entrance surface dose. The values of effective tube current time product (Eff. mAs) of each z-axis position were recorded. Results: The Eff. mAs of wide volume scan mode is lower than that of helical scan but the surface dose from over-lapping between volumes ranges from 20% to 65% higher than other region. The contribution of overlapping dose is proportional to the number of volumes of the wide volume scan mode. Discussion: We have assessed the radiation dose distribution of four adult routine protocols with wide volume scan mode in a 320 detectorrow CT scanner and compared it with those of helical scan mode. The over-lapping dose that locates in radiosensitive organ region such as thyroid, breast, or gonads will increase the radiation risk burden to a patient.
Figure 1-14: (a) Anterior-to-posterior (AP) and (b) lateral (LAT) surface doses comparison between helical scan and wide volume scan modes of (1) head, (2) chest, (3) abdomen, and (4) chest-abdomen-pelvis (CAP) CT examinations.
the 20 mSv/y as a dose limit for radiation workers. It has been previously indicated that the risk of low birth weight (LBW) is enhanced due to maternal medical exposures during pregnancy Objectives: The main aim of this study was to find out whether there is a relationship between long term exposure to background radiation levels above the normal amount and the risk of low birth weight. Materials and methods: A cross-sectional study was conducted in high background radiation areas (HBRAs) of Ramsar and neighboring areas with normal levels of background radiation (NBRAs). An interview was conducted using a questionnaire administered to 320 women from HBRAs and 280 women from NBRAs by an expert radiation biologist. Screening and stratified random sampling were used for selection of the subjects (vaginal or caesarian). Results: The mean birth weight of the newborns to mothers from HBRAs was 2820.3 ± 654.2 g. and that of the newborns to the mothers from NBRAs was 2925.2 ± 543.2 g. The difference between the mean weight of the newborns of the mothers from HBRAs and NBRAs was statistically significant (P¼0.034). Conclusions: In this study, it was revealed that the birth weight may be associated with the level of background radiation in the mothers’ living area before and during pregnancy. However, the results of the present study question the reports given by previous studies revealing that pregnant mothers exposure to ionizing radiation enhanced the occurrence of low birth weight. Keywords: Ionizing radiation, Non-ionizing radiation, Pregnancy, Low birth weight, Term labor RADIATION DOSE IN ENDOSCOPIC RETROGRADE CHOLANGIOPANCREATOGRAPHY: DOES THE OPERATOR EXPERIENCE REALLY MATTER? V. Tsapaki a, K. Paraskeva a, A. Giannakopoulos a, S. Papasavvas a, N. Mathou a, P. Aggelogiannopoulou a, S. Triantopoulou a, H. Al Malki a, I. Tsalafoutas b, Ch. Triantopoulou a, J.A. Karagiannis a. a Konstantopoulio General Hospital of Nea Ionia, Athens, Greece; b “Agios Savvas” General Hospital, Athens, Greece Background: Endoscopic retrograde cholangiopancreatography (ERCP) is the gold standard technique for treating the disorders of the billiary and pancreatic ducts . During ERCP, a side viewing endoscope passes through the mouth, esophagus and stomach into the duodenum and the papilla of Vater is cannulated using fluoroscopy as a guidance. During fluoroscopic guidance, the position of the endoscope and its relationship within the duodenum is .verified in real time. Therefore, extensive use of X-ray fluoroscopy and a large number of radiographs are possible. It is also a highly technical and complex technique that greatly depends on the endoscopist’s experience. The quality and success of ERCP as well as limitation of various clinical complications depend on the training of the endoscopist. The aim of the study was to compare patient’s radiation exposure during ERCP, in relation to the endoscopist’s experience. Materials and methods: All ERCPs were performed using a conventional radiology X-ray machine (Philips Essenta) with a Kerma Area Product (KAP) meter installed in the X-ray tube.. The meter was calibrated according to the method summarized in the ‘national protocol for patient dose measurements in diagnostic radiology’ developed by the National Radiological Protection Board (NRPB). In each ERCP, KAP in Gycm2, fluoroscopy time (FT) in min and total number of X-ray films (F) were recorded . All ERCP procedures were done under sedation and with a fixed set-up for the patient. The X-ray system was controlled by the radiographer according to endoscopist’s instructions. The ERCPs were performed by a high volume endoscopist ( HVE) (more than 200 ERCP/year for 10 years) and a low volume endoscopist (LVE) in its first year after finishing basic ERCP training Results: A total number of 239 patients were included in the study, 56 of which were performed by LVE and 183 by HVE. Median KAP was significantly lower for the patients done by the HVE ( 11,42 Gy.cm2 (range: 0,81-175,93 Gy.cm2) vs 23,14 Gy.cm2 (range: 1,20-198,02 Gy.cm2).
e57
Similarly, FT was shorter for the HVE (Median T: 3,5 min) versus LVE (Median T: 2,3 min). For both operators, radiation dose was correlated with number of films taken (f), (LVE): 0,59 and HVE: 0,64. Conclusion: Our study shows that ERCP patient radiation dose is significantly higher for a low volume cases endoscopist. It is therefore essential to draw the attention of the ERCP practitioners, especially the beginners, to the radiation their patients receive compared to high volume endoscopists. COMPARISON OF ENTRANCE SURFACE DOSE OF FOUR ROUTINE CT EXAMINATIONS: HELICAL SCAN VERSUS WIDE VOLUME SCAN MODES Ying-Lan Liao a, Yan-Shi Chen b, Hui-Yu Tsai b, c, d. a Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu 300, Taiwan; b Department of Medical Imaging and Radiological Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan; c Institute for Radiological Research, Chang Gung University / Chang Gung Memorial Hospital, Taoyuan 333, Taiwan; d Healthy Aging Research Center, Chang Gung University, Taoyuan 333, Taiwan Background: Computed tomography (CT) plays an important role in diagnostic radiology for radiologists because of excellent image quality within a very short acquisition time. A 320-detector row CT scanner has a collimation width up to 160 mm and a specific scan mode called wide volume scan mode based on axial scan mode was developed. The total scan length of a patient is adjusted automatically into several scan ranges equally. Then the patient will be scanned like a step and shoot procedure to acquire the imaging data. However, the mechanism of the wide volume scan mode together with the automatic tube current modulation (ATCM) technique remains unclear. The purpose of our study was to assess the surface dose distribution during wide volume scan mode of four adult CT examinations and compare it with those of helical scan modes. Materials and methods: An averaged-sized anthropomorphic phantom was scanned with four adult CT examinations (head, chest, abdomen, and chest-abdomen-pelvis (CAP)) of a 320 detector-row CT scanner (Aquilion ONE, Toshiba, Japan) (Table 1). The ATCM technique (SureExposure 3D, Toshiba, Japan) was used during the wide volume scan mode and helical scan mode. The radiochromic film strips (Gafchromic XR-QA2, ISP, USA) were used to measure the entrance surface dose. The values of effective tube current time product (Eff. mAs) of each z-axis position were recorded. Results: The Eff. mAs of wide volume scan mode is lower than that of helical scan but the surface dose from over-lapping between volumes ranges from 20% to 65% higher than other region. The contribution of overlapping dose is proportional to the number of volumes of the wide volume scan mode. Discussion: We have assessed the radiation dose distribution of four adult routine protocols with wide volume scan mode in a 320 detectorrow CT scanner and compared it with those of helical scan mode. The over-lapping dose that locates in radiosensitive organ region such as thyroid, breast, or gonads will increase the radiation risk burden to a patient.
Figure 1-14: (a) Anterior-to-posterior (AP) and (b) lateral (LAT) surface doses comparison between helical scan and wide volume scan modes of (1) head, (2) chest, (3) abdomen, and (4) chest-abdomen-pelvis (CAP) CT examinations.