Pub Date : 2021-11-11DOI: 10.22038/IJMP.2021.57903.1971
H. Ghaznavi, H. Emami, Farzaneh Aallaveisi, P. Shokrani
Background: In radiation treatment of stage one seminoma (SOS) induced secondary cancer in organs at risk (OARs), located in or out of the radiation fields, is a late toxicity of major concern. This study aimed to compare the secondary cancer risk in radiotherapy of SOS in two-dimensional conventional radiation therapy (2D) and three-dimensional conformal radiation therapy (3DCRT). Materials and Methods: CT scan images of 10 patients with SOS were used to design 2D conventional and 3D conformal treatment plans using 25 Gy in 20 sessions. The life attributable risk (LAR) of liver, stomach, and colon were calculated using the organ equivalent dose (OED) model for organs in radiation field and Biologic Effects of Ionizing Radiation VII (BEIR VII) model for organs out of field. Results: LAR of OARs in radiation field such as, liver and stomach was obtained 40% higher in the 2D treatment than in the 3D treatment, while as for the colon, it was 17% lower in the 2D treatment than in the 3D treatment. The LAR values of kidneys located outside the radiation field in the 2D treatment were calculated 0.04%. Conclusion: Increasing the prescribed dose (25 vs. 20) as well as the number of treatment sessions (20 vs. 10) resulted in increasing in the LAR of at-risk organs such as liver, stomach, colon. Therefore, estimating cancer risk of critical organs exposed to radiation through examining the effects of dose fractionation and prescribed doses can be used in optimizing of treatment plan for seminoma, selection of a better treatment method by oncologists, and patient follow-up.
{"title":"Secondary cancer risk after radiotherapy of seminoma stage one","authors":"H. Ghaznavi, H. Emami, Farzaneh Aallaveisi, P. Shokrani","doi":"10.22038/IJMP.2021.57903.1971","DOIUrl":"https://doi.org/10.22038/IJMP.2021.57903.1971","url":null,"abstract":"Background: In radiation treatment of stage one seminoma (SOS) induced secondary cancer in organs at risk (OARs), located in or out of the radiation fields, is a late toxicity of major concern. This study aimed to compare the secondary cancer risk in radiotherapy of SOS in two-dimensional conventional radiation therapy (2D) and three-dimensional conformal radiation therapy (3DCRT).\u0000Materials and Methods: CT scan images of 10 patients with SOS were used to design 2D conventional and 3D conformal treatment plans using 25 Gy in 20 sessions. The life attributable risk (LAR) of liver, stomach, and colon were calculated using the organ equivalent dose (OED) model for organs in radiation field and Biologic Effects of Ionizing Radiation VII (BEIR VII) model for organs out of field.\u0000Results: LAR of OARs in radiation field such as, liver and stomach was obtained 40% higher in the 2D treatment than in the 3D treatment, while as for the colon, it was 17% lower in the 2D treatment than in the 3D treatment. The LAR values of kidneys located outside the radiation field in the 2D treatment were calculated 0.04%.\u0000 Conclusion: Increasing the prescribed dose (25 vs. 20) as well as the number of treatment sessions (20 vs. 10) resulted in increasing in the LAR of at-risk organs such as liver, stomach, colon. Therefore, estimating cancer risk of critical organs exposed to radiation through examining the effects of dose fractionation and prescribed doses can be used in optimizing of treatment plan for seminoma, selection of a better treatment method by oncologists, and patient follow-up.","PeriodicalId":14613,"journal":{"name":"Iranian Journal of Medical Physics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46112357","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-11-04DOI: 10.22038/IJMP.2021.58875.1986
S. Jafari, Seyed Abdolhamid Talebi, R. Afzalipour, F. Tabeie, S. Shirmardi
Introduction: This study aimed to investigate the absorbed dose of scatter radiation in coronary angiography. Materials and Methods: The scatter radiation dose was measured for 20 patients at four different heights (50,100, 150 and 165 cm) from the floor. Spatial dose was measured by RTI Piranha r100b solid state dose probe at different points around the patient in actual clinical situation and with phantom. Also the measurement was repeated using a designed phantom in fluoroscopy and cine mode in PA, LLAT, LPO, RAO and RLAT projections. The dose to dose area product (DAP) conversion coefficients for each organ were calculated. Results: The dose rate at different heights between the projections on the patient and the phantom as well as organ dose DAP conversion coefficients were different (p˂0.05). It was found that the dose rate changes in fluoroscopic mode compared to cine mode are significantly different (p = 0.001). The dose rate in cine mode is approximately four times of that in fluoroscopy mode. The dose rate around the cardiologist waist could be reduced by 37 – 43 % with a displacement of 20cm away. Conclusion: Taking a suitable projection could indeed reduce the dose rate delivered to the angiography team. In this study, the effective dose rate received by the cardiologist’s eyes was higher than those reported by ICRP.
{"title":"Scatter radiation absorbed dose distribution in coronary angiography: A measurement based study","authors":"S. Jafari, Seyed Abdolhamid Talebi, R. Afzalipour, F. Tabeie, S. Shirmardi","doi":"10.22038/IJMP.2021.58875.1986","DOIUrl":"https://doi.org/10.22038/IJMP.2021.58875.1986","url":null,"abstract":"Introduction: This study aimed to investigate the absorbed dose of scatter radiation in coronary angiography. Materials and Methods: The scatter radiation dose was measured for 20 patients at four different heights (50,100, 150 and 165 cm) from the floor. Spatial dose was measured by RTI Piranha r100b solid state dose probe at different points around the patient in actual clinical situation and with phantom. Also the measurement was repeated using a designed phantom in fluoroscopy and cine mode in PA, LLAT, LPO, RAO and RLAT projections. The dose to dose area product (DAP) conversion coefficients for each organ were calculated. Results: The dose rate at different heights between the projections on the patient and the phantom as well as organ dose DAP conversion coefficients were different (p˂0.05). It was found that the dose rate changes in fluoroscopic mode compared to cine mode are significantly different (p = 0.001). The dose rate in cine mode is approximately four times of that in fluoroscopy mode. The dose rate around the cardiologist waist could be reduced by 37 – 43 % with a displacement of 20cm away. Conclusion: Taking a suitable projection could indeed reduce the dose rate delivered to the angiography team. In this study, the effective dose rate received by the cardiologist’s eyes was higher than those reported by ICRP.","PeriodicalId":14613,"journal":{"name":"Iranian Journal of Medical Physics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47814279","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-11-04DOI: 10.22038/IJMP.2021.59219.1996
Mohamdreza Armanmehr, Mohammad Mahdi Jalali, A. Shokri, Ali Heydari Chaleshtori
Abstract Background: Sometimes, a patient is referred to a medical imaging center and receives a medical image that it is not good and sometimes poor quality image, which the doctor orders to re-image with a drug contrast agent (in CT scan imaging). On the other hand, small liver tumors sometimes have to reach 4 cm to be detectable. At this time, practical action is difficult to provide a proper image. Moreover, injectable tracking materials in PET scans often have short half-lives that are very expensive to maintain. Purpose: -Investigation of the effect of cobalt oxide nanoparticles on the quality of CT scan images from laboratory mice. -Evaluation of the effect of cobalt oxide nanoparticles on the quality of live PET scan images and diagnosis of small tumors in mice. Method: In this study, the coupling method was used to prepare the cobalt oxide nanoparticles. Co3O4 nanoparticle coatings are used for this purpose. They were investigated through FT-IR analysis, X-ray diffraction and magnetization curve of the crystalline sample. For this purpose a 2000 μA proton bombardment with an energy of 22 million eV and a current of 180 μA was used. The final product activity was 23 mM. A. The nanoparticles were injected into Mice with tumors in the legs, and PET images were obtained at 1, 6, 12, and 24 h intervals. Results: 1- After injection the cobalt oxide nanoparticles into the mice and CT scan imaging, the better clarity and detection Mice viscera were obtained. 2-Cobalt oxide nanoparticles showed good performance in PET scan images after injection into mice in the first first 24 hours. Conclusion: Cobalt oxide nanoparticles behave well for use as a pharmacological contrast agent in CT scan and PET scan imaging. Keywords: PET, tumor, Radiotracer, nanoparticles, CT-Scan.
{"title":"The effect of cobalt oxide nanoparticles on improving the quality of CT and PET scan medical imaging","authors":"Mohamdreza Armanmehr, Mohammad Mahdi Jalali, A. Shokri, Ali Heydari Chaleshtori","doi":"10.22038/IJMP.2021.59219.1996","DOIUrl":"https://doi.org/10.22038/IJMP.2021.59219.1996","url":null,"abstract":"Abstract\u0000Background: Sometimes, a patient is referred to a medical imaging center and receives a medical image that it is not good and sometimes poor quality image, which the doctor orders to re-image with a drug contrast agent (in CT scan imaging). On the other hand, small liver tumors sometimes have to reach 4 cm to be detectable. At this time, practical action is difficult to provide a proper image. Moreover, injectable tracking materials in PET scans often have short half-lives that are very expensive to maintain.\u0000Purpose: \u0000-Investigation of the effect of cobalt oxide nanoparticles on the quality of CT scan images from laboratory mice.\u0000-Evaluation of the effect of cobalt oxide nanoparticles on the quality of live PET scan images and diagnosis of small tumors in mice.\u0000Method: In this study, the coupling method was used to prepare the cobalt oxide nanoparticles. Co3O4 nanoparticle coatings are used for this purpose. They were investigated through FT-IR analysis, X-ray diffraction and magnetization curve of the crystalline sample. For this purpose a 2000 μA proton bombardment with an energy of 22 million eV and a current of 180 μA was used. The final product activity was 23 mM. A. The nanoparticles were injected into Mice with tumors in the legs, and PET images were obtained at 1, 6, 12, and 24 h intervals.\u0000Results:\u00001- After injection the cobalt oxide nanoparticles into the mice and CT scan imaging, the better clarity and detection Mice viscera were obtained.\u00002-Cobalt oxide nanoparticles showed good performance in PET scan images after injection into mice in the first first 24 hours.\u0000Conclusion: Cobalt oxide nanoparticles behave well for use as a pharmacological contrast agent in CT scan and PET scan imaging.\u0000\u0000Keywords: PET, tumor, Radiotracer, nanoparticles, CT-Scan.","PeriodicalId":14613,"journal":{"name":"Iranian Journal of Medical Physics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46974469","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-11-04DOI: 10.22038/IJMP.2021.59399.1997
F. Zarei, Zeynab Mashayekhi, Vani Vardhan Chatterjee, S. Chatterjee, R. R. Haghighi
Introduction: Computed Tomography (CT) is nowadays used widely to differentiate normal brain cranium sutures from abnormal ones in pediatric patients with the aim of early treatment. This study tried to develop a low-dose CT protocol with acceptable image quality of skull bone in order to evaluate craniosynostosis. Materials and Methods: In this study a cranium bone of human cadaver was scanned with standard and reduced dose protocols. Two radiologists verified the quality of skull bone image acquired from the protocol in which there had been 60% dose reduction to scan pediatric patients. The quality of low dose protocol of three dimensional (3D) CT images of skull bone of 57 pediatric subjects suspected of craniosynostosis were compared with standard-dose skull CT images of 44 patients of the same age range. Volume CT dose index (CTDIvol), dose-length product (DLP), and effective dose (ED) were used to evaluate CT dose protocols. Comparison was made by two sample t-test. Results: Mean and standard deviations of CTDIvol, DLP, and ED of standard and reduced doses were 12.4±2.7 mGy, 191.5±54 mGy.cm, 1.94±0.58 mSv and 5.4±0.2 mGy, 85±9 mGy.cm, 0.77±0.17 mSv, respectively, which had statistically significant difference (α=0.05). The quality of skull bone views obtained from low-dose CT protocol were found to be as good as in standard dose. Conclusion: Standard-dose 3D CT protocol of skull bone can be replaced by a 60%-reduced-dose 3D CT protocol with comparable image quality in pediatric patients suspected of craniosynostosis.
{"title":"Evaluation of Low-Dose 3D skull CT images in craniosynostosis","authors":"F. Zarei, Zeynab Mashayekhi, Vani Vardhan Chatterjee, S. Chatterjee, R. R. Haghighi","doi":"10.22038/IJMP.2021.59399.1997","DOIUrl":"https://doi.org/10.22038/IJMP.2021.59399.1997","url":null,"abstract":"Introduction: Computed Tomography (CT) is nowadays used widely to differentiate normal brain cranium sutures from abnormal ones in pediatric patients with the aim of early treatment. This study tried to develop a low-dose CT protocol with acceptable image quality of skull bone in order to evaluate craniosynostosis. \u0000Materials and Methods: In this study a cranium bone of human cadaver was scanned with standard and reduced dose protocols. Two radiologists verified the quality of skull bone image acquired from the protocol in which there had been 60% dose reduction to scan pediatric patients. The quality of low dose protocol of three dimensional (3D) CT images of skull bone of 57 pediatric subjects suspected of craniosynostosis were compared with standard-dose skull CT images of 44 patients of the same age range. Volume CT dose index (CTDIvol), dose-length product (DLP), and effective dose (ED) were used to evaluate CT dose protocols. Comparison was made by two sample t-test. \u0000Results: Mean and standard deviations of CTDIvol, DLP, and ED of standard and reduced doses were 12.4±2.7 mGy, 191.5±54 mGy.cm, 1.94±0.58 mSv and 5.4±0.2 mGy, 85±9 mGy.cm, 0.77±0.17 mSv, respectively, which had statistically significant difference (α=0.05). The quality of skull bone views obtained from low-dose CT protocol were found to be as good as in standard dose. \u0000Conclusion: Standard-dose 3D CT protocol of skull bone can be replaced by a 60%-reduced-dose 3D CT protocol with comparable image quality in pediatric patients suspected of craniosynostosis.","PeriodicalId":14613,"journal":{"name":"Iranian Journal of Medical Physics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47957304","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-11-03DOI: 10.22038/IJMP.2021.56970.1957
H. Ghaznavi, A. Jafari
Introduction: Following breast conserving surgery, radiotherapy is used to control the tumor and increase the survival rates of patients. After radiation therapy, organ at risk, are prone to organ toxicity and secondary cancers. To compare the risk of heart disease in radiotherapy patients for left-sided in two treatment techniques of intensity modulated radiation therapy(IMRT) and three dimensional conformal radiation therapy(3DCRT) with considering blood factors, smoking, and underlying diseases. Method: 32 patients with left-sided breast cancer were used in the early stages were selected for this study. 3D-CRT and IMRT were planned to deliver prescribed dose to target volume. Schneider model was used to estimate excess absolute risk (EAR) of heart diseases, also10-years baseline risk of heart disease using Reynolds risk score for ages 50-70 years were calculated. Results: There was a significant difference in 10-year EAR of heart diseases when comparing 3D-CRT plans in IMRT (p<0.05). 10-year EAR for IMRT at low, median, and high risk groups were higher than 3DCRT. Among factors involved in baseline risk, by increasing the age, the impact of smoking on increasing EAR was clearer compared to the family history of heart disease. Conclusions: IMRT had a more uniform dose distribution and a better conformity-homogeneity index than 3DCRT. However, the mean heart dose and subsequently the risk of heart disease significantly were lower in 3DCRT. Adding risk factors which are effective in the development of heart disease can result in more accurate estimates of the risk of heart disease after breast cancer radiotherapy.
{"title":"Left-sided Breast Cancer Radiotherapy and Risk of Heart Diseases: with Considering Baseline Risk of Heart Diseases","authors":"H. Ghaznavi, A. Jafari","doi":"10.22038/IJMP.2021.56970.1957","DOIUrl":"https://doi.org/10.22038/IJMP.2021.56970.1957","url":null,"abstract":"Introduction: Following breast conserving surgery, radiotherapy is used to control the tumor and increase the survival rates of patients. After radiation therapy, organ at risk, are prone to organ toxicity and secondary cancers. To compare the risk of heart disease in radiotherapy patients for left-sided in two treatment techniques of intensity modulated radiation therapy(IMRT) and three dimensional conformal radiation therapy(3DCRT) with considering blood factors, smoking, and underlying diseases. \u0000Method: 32 patients with left-sided breast cancer were used in the early stages were selected for this study. 3D-CRT and IMRT were planned to deliver prescribed dose to target volume. Schneider model was used to estimate excess absolute risk (EAR) of heart diseases, also10-years baseline risk of heart disease using Reynolds risk score for ages 50-70 years were calculated.\u0000Results: There was a significant difference in 10-year EAR of heart diseases when comparing 3D-CRT plans in IMRT (p<0.05). 10-year EAR for IMRT at low, median, and high risk groups were higher than 3DCRT. Among factors involved in baseline risk, by increasing the age, the impact of smoking on increasing EAR was clearer compared to the family history of heart disease. \u0000Conclusions: IMRT had a more uniform dose distribution and a better conformity-homogeneity index than 3DCRT. However, the mean heart dose and subsequently the risk of heart disease significantly were lower in 3DCRT. Adding risk factors which are effective in the development of heart disease can result in more accurate estimates of the risk of heart disease after breast cancer radiotherapy.","PeriodicalId":14613,"journal":{"name":"Iranian Journal of Medical Physics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48254207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-11-01DOI: 10.22038/IJMP.2021.56735.1952
Aitidir Belaid, R. Khelifi, Z. Lounis-Mokrani
Introduction The large number of coronary angiography procedures and inappropriate use of radiation protection equipment constitute a high occupational radiological risk for cardiologists generated by chronic exposure to low doses of radiation, in particular for parts of the body unprotected such as eyes and head. Materials and methods The eye lens dose was evaluated for seven cardiologists performing coronary angiography procedures over three months. The equivalent dose to the eye lens, Hp (3), was calculated from the equivalent dose to the skin, Hp (0.07), measured by an active dosimeter worn at the cardiologist's neck. The annual eye lens dose and the brain cancer risk were estimated. The correlation between the eye lens dose and the procedure parameters including the dose-area product, the fluoroscopy duration, and the number of fluography images was studied. Phantom-based measurements by a babyline 81 allowed to separate the contribution of the two modes, fluoroscopy and fluorography to the total dose and therefore, to propose another method of continuous lens dose monitoring. Finally, an optimization study was performed to reduce the eye lens dose and consequently the brain cancer risk. Results Two cardiologists have exceeded the annual lens dose limit (28mSv, 22mSv). A good correlation was found between Hp (3) and the fluoroscopy duration (R² = 0.89). The measurements showed that most of the exposure was in fluoroscopic mode (89%). The optimization study reduced the annual eye lens dose to 2.9 mSv and 2.3 mSv, respectively, for these two cardiologists. Thus, this decreased the brain cancer risk by a factor of ten. Conclusion The high eye lens annual doses recorded in this study are due to non-compliance with radiation protection rules. The proposed optimization process reduced the eye lens dose and the risk of brain cancer, at least, by a factor of ten.
{"title":"Occupational exposure evaluation and radiation protection optimization in coronary angiography procedures","authors":"Aitidir Belaid, R. Khelifi, Z. Lounis-Mokrani","doi":"10.22038/IJMP.2021.56735.1952","DOIUrl":"https://doi.org/10.22038/IJMP.2021.56735.1952","url":null,"abstract":"Introduction\u0000The large number of coronary angiography procedures and inappropriate use of radiation protection equipment constitute a high occupational radiological risk for cardiologists generated by chronic exposure to low doses of radiation, in particular for parts of the body unprotected such as eyes and head.\u0000Materials and methods\u0000The eye lens dose was evaluated for seven cardiologists performing coronary angiography procedures over three months. The equivalent dose to the eye lens, Hp (3), was calculated from the equivalent dose to the skin, Hp (0.07), measured by an active dosimeter worn at the cardiologist's neck. The annual eye lens dose and the brain cancer risk were estimated. The correlation between the eye lens dose and the procedure parameters including the dose-area product, the fluoroscopy duration, and the number of fluography images was studied. Phantom-based measurements by a babyline 81 allowed to separate the contribution of the two modes, fluoroscopy and fluorography to the total dose and therefore, to propose another method of continuous lens dose monitoring. Finally, an optimization study was performed to reduce the eye lens dose and consequently the brain cancer risk.\u0000Results \u0000Two cardiologists have exceeded the annual lens dose limit (28mSv, 22mSv). A good correlation was found between Hp (3) and the fluoroscopy duration (R² = 0.89). The measurements showed that most of the exposure was in fluoroscopic mode (89%). The optimization study reduced the annual eye lens dose to 2.9 mSv and 2.3 mSv, respectively, for these two cardiologists. Thus, this decreased the brain cancer risk by a factor of ten. \u0000Conclusion \u0000The high eye lens annual doses recorded in this study are due to non-compliance with radiation protection rules. The proposed optimization process reduced the eye lens dose and the risk of brain cancer, at least, by a factor of ten.","PeriodicalId":14613,"journal":{"name":"Iranian Journal of Medical Physics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42826929","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-10-12DOI: 10.22038/IJMP.2021.56852.1954
F. Zarei, Mahdokht Nasiri, Z. Etemadi, R. R. Haghighi, S. Chatterjee, Pouria Abdollahi Khaneghah, Vani Vardhan Chatterjee
Introduction: The importance of estimating patient-sized adjusted radiation dose for pediatric computed tomography (CT) has long been accepted. High doses of ionizing radiation to children are often common in chest CT examination, as the volume CT dose index (CTDIvol) is measured by a 32 cm phantom. Our study was aimed to evaluate the effectiveness of size-specific dose estimate (SSDE) to compensate the underestimated pediatric absorbed dose. Materials and methods: CTDIvol and dose-length product (DLP) of 320 pediatric chest CT (<1, 1-5, 5-10, 10-15 years) were obtained from Picture-Archieving and Communication System (PACS) in a hospital affiliated to the Shiraz University of Medical Sciences. CTDIvol was converted to SSDE based on the patient's effective diameter. The Statistical Package for Social Science (SPSS) was used for data analysis. Results: The variations between standard phantom (32cm) and the patients' mean effective diameter were approximately 65%, 57%, 47%, and 38%, across <1, 1-5, 5-10, 10-15 year age groups, respectively. Mean of SSDE for each age group was significantly higher than the corresponding CTDIvol values. Also, mean CTDIvol and SSDE values differed between age groups significantly (p<0.001). Results showed a strong correlation between age and the two dose indicators, CTDIvol (0.361) and SSDE (0.184) with p<0.05. Conclusion: Pediatrics receive radiation doses comparable to the dose for adult-sized patients in chest CT protocol if dosimetry procedure is not individualized. Thus, the application of size-based conversion coefficient is paramount in estimating the absorbed dose in pediatric chest CT.
{"title":"Evaluation of Size-Specific Dose Estimates for Optimizing Pediatric Chest CT Protocol","authors":"F. Zarei, Mahdokht Nasiri, Z. Etemadi, R. R. Haghighi, S. Chatterjee, Pouria Abdollahi Khaneghah, Vani Vardhan Chatterjee","doi":"10.22038/IJMP.2021.56852.1954","DOIUrl":"https://doi.org/10.22038/IJMP.2021.56852.1954","url":null,"abstract":"Introduction: The importance of estimating patient-sized adjusted radiation dose for pediatric computed tomography (CT) has long been accepted. High doses of ionizing radiation to children are often common in chest CT examination, as the volume CT dose index (CTDIvol) is measured by a 32 cm phantom. Our study was aimed to evaluate the effectiveness of size-specific dose estimate (SSDE) to compensate the underestimated pediatric absorbed dose. \u0000Materials and methods: CTDIvol and dose-length product (DLP) of 320 pediatric chest CT (<1, 1-5, 5-10, 10-15 years) were obtained from Picture-Archieving and Communication System (PACS) in a hospital affiliated to the Shiraz University of Medical Sciences. CTDIvol was converted to SSDE based on the patient's effective diameter. The Statistical Package for Social Science (SPSS) was used for data analysis. \u0000Results: The variations between standard phantom (32cm) and the patients' mean effective diameter were approximately 65%, 57%, 47%, and 38%, across <1, 1-5, 5-10, 10-15 year age groups, respectively. Mean of SSDE for each age group was significantly higher than the corresponding CTDIvol values. Also, mean CTDIvol and SSDE values differed between age groups significantly (p<0.001). Results showed a strong correlation between age and the two dose indicators, CTDIvol (0.361) and SSDE (0.184) with p<0.05. \u0000Conclusion: Pediatrics receive radiation doses comparable to the dose for adult-sized patients in chest CT protocol if dosimetry procedure is not individualized. Thus, the application of size-based conversion coefficient is paramount in estimating the absorbed dose in pediatric chest CT.","PeriodicalId":14613,"journal":{"name":"Iranian Journal of Medical Physics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46946463","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-09-19DOI: 10.22038/IJMP.2021.57910.1966
Garima Gaur, Raja Singh, O. Gurjar, P. Garg, R. Grover, M. Kang, Gurpreet Kaur, S. Sheetal, V. K. Dangwal
Background: The purpose of this study is to evaluate and compare treatment plan quality metrics for postmastectomy breast cancer patients using 3Dimensional conformal radiotherapy (3DCRT) and intensity modulated radiotherapy (IMRT) planning techniques. Materials and Methods: The current study included 50 postmastectomy breast cancer patients out of which 24 were planned with 3DCRT and 26 with IMRT technique. Treatment plan quality metrics namely homogeneity index (HI), conformity index (CI), conformation number (CN), uniformity index (UI) and spillage index (R50), volume receiving 110% and 95% of prescribed dose (V110% and V95%) were calculated and compared for the two planning techniques. Results: IMRT plans have better conformity, homogeneity indices and low V110% than 3DCRT plans with almost similar R50% and V95%. Conclusions: Quantitative values of radiotherapy treatment plan quality metrics for the target are found in favour of IMRT technique than 3DCRT. Implementation of these five parameters is helpful for evaluating treatment plans along with slice by slice and DVH analysis. Keywords: Carcinoma of Breast; conformal planning techniques; radiotherapy.
{"title":"Radiotherapy treatment plan quality metrics for breast cancer patients using conformal planning techniques","authors":"Garima Gaur, Raja Singh, O. Gurjar, P. Garg, R. Grover, M. Kang, Gurpreet Kaur, S. Sheetal, V. K. Dangwal","doi":"10.22038/IJMP.2021.57910.1966","DOIUrl":"https://doi.org/10.22038/IJMP.2021.57910.1966","url":null,"abstract":"Background: The purpose of this study is to evaluate and compare treatment plan quality metrics for postmastectomy breast cancer patients using 3Dimensional conformal radiotherapy (3DCRT) and intensity modulated radiotherapy (IMRT) planning techniques.\u0000Materials and Methods: The current study included 50 postmastectomy breast cancer patients out of which 24 were planned with 3DCRT and 26 with IMRT technique. Treatment plan quality metrics namely homogeneity index (HI), conformity index (CI), conformation number (CN), uniformity index (UI) and spillage index (R50), volume receiving 110% and 95% of prescribed dose (V110% and V95%) were calculated and compared for the two planning techniques.\u0000Results: IMRT plans have better conformity, homogeneity indices and low V110% than 3DCRT plans with almost similar R50% and V95%.\u0000Conclusions: Quantitative values of radiotherapy treatment plan quality metrics for the target are found in favour of IMRT technique than 3DCRT. Implementation of these five parameters is helpful for evaluating treatment plans along with slice by slice and DVH analysis.\u0000Keywords: Carcinoma of Breast; conformal planning techniques; radiotherapy.","PeriodicalId":14613,"journal":{"name":"Iranian Journal of Medical Physics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46433138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-09-15DOI: 10.22038/IJMP.2021.56733.1951
Ahmed Rizk Ali Mostafa, Abdelwassie Hussein, M. Galal, K. Shahat
Introduction: The study aimed to provide the dose accuracy effects between Anisotropic Analytical algorithm (AAA) and the deterministic solver Acuros XB (AXB) that are available on Eclipse TPS (Varian Medical Systems, Palo Alto, CA) treatment planning system (TPS). The different is due to the electron transport difference in case of small fieldsMaterial and methods: For the study non-small cell lung cancer (NSCLC) patient CT scans are used to do retrospective SBRT plans via AAA and recalculated by AXB dose calculation algorithms using Eclipse treatment planning system. The main dosimetric comparison parameters are: Conformity index (CI), Homogeneity Index (HI), Gradient Index (GI), Target mean dose and calculation time. Results: Based on the results, the CI is (1.45±0.55) to (1.85±0.7). The HI are (0.15±0.07) and (0.13±0.08), the Gradient index GI for AAA were (4.8±2.6) and for AXB reaches to (7.4±3.8) and the maximum dose for PTV are differed about 2.3% to 4.5%, mean dose and the calculation time significant similar for AAA and AXB respectively.Conclusion: As the findings using the deterministic solver AXB in calculation for case of low density like lung cases is more accurate than AAA calculation Algorithm in SBRT treatment
简介：该研究旨在提供各向异性分析算法（AAA）和Eclipse TPS（Varian Medical Systems，Palo Alto，CA）治疗计划系统（TPS）上可用的确定性求解器Acuros XB（AXB）之间的剂量准确性影响。不同的原因是小电场情况下的电子传输差异材料和方法：对于研究非小细胞肺癌NSCLC）患者的CT扫描，通过AAA进行回顾性SBRT计划，并使用Eclipse治疗计划系统通过AXB剂量计算算法重新计算。主要的剂量比较参数有：一致性指数（CI）、均匀性指数（HI）、梯度指数（GI）、目标平均剂量和计算时间。结果：根据结果，CI为（1.45±0.55）至（1.85±0.7）。HI为（0.15±0.07）和（0.13±0.08），AAA的梯度指数GI为（4.8±2.6），AXB达到（7.4±3.8），PTV的最大剂量相差约2.3%至4.5%，AAA和AXB的平均剂量和计算时间分别显著相似。结论：在SBRT治疗中，使用确定性求解器AXB计算低密度类肺病例的结果比AAA计算算法更准确
{"title":"The impact of dose calculation algorithm for SBRT lung cancer radiotherapy treatment","authors":"Ahmed Rizk Ali Mostafa, Abdelwassie Hussein, M. Galal, K. Shahat","doi":"10.22038/IJMP.2021.56733.1951","DOIUrl":"https://doi.org/10.22038/IJMP.2021.56733.1951","url":null,"abstract":"Introduction: The study aimed to provide the dose accuracy effects between Anisotropic Analytical algorithm (AAA) and the deterministic solver Acuros XB (AXB) that are available on Eclipse TPS (Varian Medical Systems, Palo Alto, CA) treatment planning system (TPS). The different is due to the electron transport difference in case of small fieldsMaterial and methods: For the study non-small cell lung cancer (NSCLC) patient CT scans are used to do retrospective SBRT plans via AAA and recalculated by AXB dose calculation algorithms using Eclipse treatment planning system. The main dosimetric comparison parameters are: Conformity index (CI), Homogeneity Index (HI), Gradient Index (GI), Target mean dose and calculation time. Results: Based on the results, the CI is (1.45±0.55) to (1.85±0.7). The HI are (0.15±0.07) and (0.13±0.08), the Gradient index GI for AAA were (4.8±2.6) and for AXB reaches to (7.4±3.8) and the maximum dose for PTV are differed about 2.3% to 4.5%, mean dose and the calculation time significant similar for AAA and AXB respectively.Conclusion: As the findings using the deterministic solver AXB in calculation for case of low density like lung cases is more accurate than AAA calculation Algorithm in SBRT treatment","PeriodicalId":14613,"journal":{"name":"Iranian Journal of Medical Physics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42633692","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-09-08DOI: 10.22038/IJMP.2021.56076.1934
Imane Ou-saada, S. Douama, Youssef Bouzekraoui, Hilde Bosmann, L. Cockmartin, M. Campoleoni, Oumnia Ou-saada, Rachid Errifai, L. B. Drissi, F. Bentayeb
Purpose: The aim of this study is to estimate local DRL values for computed tomography (CT) procedures, corresponding to Head, Chest, and Abdomen-Pelvis examinations (single acquisition), in Moroccan hospitals.Methods: A total of 1917 diagnostic CT examinations were included in this study. Firstly, we analyzed the CT dose indicators CTDIvol and DLP of all the examinations collected. Although we have proposed local diagnostic reference levels just for: head, thorax, abdomen-pelvis, due to the lack of data for the other examinations. Furthermore, we calculated the effective dose for chest examination using CT-expo software to estimate effective and organ dose for chest CT.The results: showed that the estimated local DRLs using CTDIvol are 48 mGy, 14 mGy, and 12 mGy for head, chest, and abdomen-pelvis respectively, and 986 mGy.cm, 496 mGy.cm, and 651 mGy.cm for DLP, respectively.Conclusion: This work establishes local DRLs for CTDIvol and total DLP for head, chest, and abdomen-pelvis procedures and proposes chest effective doses for adult patients. The study shows that the results are conforming to the literature.
{"title":"Detailed CT dosimetry in Moroccan hospitals as a preparation for the development of national DRL’s.","authors":"Imane Ou-saada, S. Douama, Youssef Bouzekraoui, Hilde Bosmann, L. Cockmartin, M. Campoleoni, Oumnia Ou-saada, Rachid Errifai, L. B. Drissi, F. Bentayeb","doi":"10.22038/IJMP.2021.56076.1934","DOIUrl":"https://doi.org/10.22038/IJMP.2021.56076.1934","url":null,"abstract":"Purpose: The aim of this study is to estimate local DRL values for computed tomography (CT) procedures, corresponding to Head, Chest, and Abdomen-Pelvis examinations (single acquisition), in Moroccan hospitals.Methods: A total of 1917 diagnostic CT examinations were included in this study. Firstly, we analyzed the CT dose indicators CTDIvol and DLP of all the examinations collected. Although we have proposed local diagnostic reference levels just for: head, thorax, abdomen-pelvis, due to the lack of data for the other examinations. Furthermore, we calculated the effective dose for chest examination using CT-expo software to estimate effective and organ dose for chest CT.The results: showed that the estimated local DRLs using CTDIvol are 48 mGy, 14 mGy, and 12 mGy for head, chest, and abdomen-pelvis respectively, and 986 mGy.cm, 496 mGy.cm, and 651 mGy.cm for DLP, respectively.Conclusion: This work establishes local DRLs for CTDIvol and total DLP for head, chest, and abdomen-pelvis procedures and proposes chest effective doses for adult patients. The study shows that the results are conforming to the literature.","PeriodicalId":14613,"journal":{"name":"Iranian Journal of Medical Physics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45483211","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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