Pub Date : 2020-01-10DOI: 10.18869/ACADPUB.IJRR.18.1.33
A. Shanei, I. Abedi, Pegah Saadatmand, A. Amouheidari, Hadi Akbari-Zadeh
Background: The aim of this study was to compare the dosimetric and radiobiological efficiency of various intensity modulated radiotherapy (IMRT) techniques with 3D conventional radiotherapy (3D-CRT) technique in the treatment of early stage oral tongue cancer. Materials and Methods: This study was performed on 38 CT images of patients who were planned with 3DCRT and three sets of IMRT treatment plans including five, seven and nine fields with prescribed dose of 66 Gy to planning target volume. The dose volume histograms, homogeneity index (HI), conformity index (CI) and normal tissue complication probability (NTCP) of main organs at risk were derived using Prowess Panther treatment planning system. Results: The results of this study indicated an increase in HI and CI for IMRT plans compared to 3D-CRT. Furthermore, IMRT techniques led to a statistically significant reduction in received dose by mandible (up to 10.10 Gy) and thyroid (up to 13.59 Gy) compared to the conventional technique used; whereas, it led to a statistically significant increase in received dose by parotid glands (up to 7.62 Gy) and brain stem (up to 9.87 Gy). In addition, IMRT increased (up to 12.79%) the probability of occurrence of parotid xerostomia and decreased mandibular complications (up to 7.76%) in comparison to conventional treatment. Conclusions: It can be concluded that IMRT can be more successful in improving oral tongue cancer treatment with more conformity and homogeneity. However, IMRT may not be required for all patients with oral tongue cancer at early stage of the disease.
{"title":"Comparison of 3D conformal and intensity modulated radiotherapy in early stage oral tongue cancer: dosimetric and radiobiological evaluation","authors":"A. Shanei, I. Abedi, Pegah Saadatmand, A. Amouheidari, Hadi Akbari-Zadeh","doi":"10.18869/ACADPUB.IJRR.18.1.33","DOIUrl":"https://doi.org/10.18869/ACADPUB.IJRR.18.1.33","url":null,"abstract":"Background: The aim of this study was to compare the dosimetric and radiobiological efficiency of various intensity modulated radiotherapy (IMRT) techniques with 3D conventional radiotherapy (3D-CRT) technique in the treatment of early stage oral tongue cancer. Materials and Methods: This study was performed on 38 CT images of patients who were planned with 3DCRT and three sets of IMRT treatment plans including five, seven and nine fields with prescribed dose of 66 Gy to planning target volume. The dose volume histograms, homogeneity index (HI), conformity index (CI) and normal tissue complication probability (NTCP) of main organs at risk were derived using Prowess Panther treatment planning system. Results: The results of this study indicated an increase in HI and CI for IMRT plans compared to 3D-CRT. Furthermore, IMRT techniques led to a statistically significant reduction in received dose by mandible (up to 10.10 Gy) and thyroid (up to 13.59 Gy) compared to the conventional technique used; whereas, it led to a statistically significant increase in received dose by parotid glands (up to 7.62 Gy) and brain stem (up to 9.87 Gy). In addition, IMRT increased (up to 12.79%) the probability of occurrence of parotid xerostomia and decreased mandibular complications (up to 7.76%) in comparison to conventional treatment. Conclusions: It can be concluded that IMRT can be more successful in improving oral tongue cancer treatment with more conformity and homogeneity. However, IMRT may not be required for all patients with oral tongue cancer at early stage of the disease.","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44753832","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 : 2020-01-10DOI: 10.18869/ACADPUB.IJRR.18.1.117
P. Shoa, I. Abedi, M. Tavakoli, A. Amouheidari, K. Jabbari
Background: The use of radiation therapy for medulloblastoma can affect children’s visual system. We estimated children’s visual system complication probability in the craniospinal irradiation (CSI) technique with threedimensional conformal radiotherapy (3D-CRT). Materials and Methods: CSI of fifteen medulloblastoma patients and a phantom were planned with 6 MV photon beams and 23.4 Gy prescribed dose. The doses of lenses were measured using thermoluminescence dosimeters (TLD). The delivered doses and complication probabilities were calculated based on the equivalent uniform dose (EUD) model to each contoured organ, including the bilateral lenses, optic nerves, retinas and optic chiasm. Results: The received dose for each organ was less than the tolerance value (p<0.001), except for the eye lens. The normal tissue complication probability (NTCP) values for all of the organs at risk (OAR) were found insignificant. The discrepancies of calculated and measured doses for the right and left lenses were 6.35% and 6.23% (p<0.001), respectively. Conclusion: The results of this study showed based on the International Commission on Radiological Protection (ICRP) publication 118 that children with medulloblastoma cancer treated with CSI with 3D-CRT method are susceptible to cataract complication.
{"title":"Estimation of the visual system complication probability on children with Medulloblastoma after Craniospinal irradiation with three-dimensional conformal radiotherapy","authors":"P. Shoa, I. Abedi, M. Tavakoli, A. Amouheidari, K. Jabbari","doi":"10.18869/ACADPUB.IJRR.18.1.117","DOIUrl":"https://doi.org/10.18869/ACADPUB.IJRR.18.1.117","url":null,"abstract":"Background: The use of radiation therapy for medulloblastoma can affect children’s visual system. We estimated children’s visual system complication probability in the craniospinal irradiation (CSI) technique with threedimensional conformal radiotherapy (3D-CRT). Materials and Methods: CSI of fifteen medulloblastoma patients and a phantom were planned with 6 MV photon beams and 23.4 Gy prescribed dose. The doses of lenses were measured using thermoluminescence dosimeters (TLD). The delivered doses and complication probabilities were calculated based on the equivalent uniform dose (EUD) model to each contoured organ, including the bilateral lenses, optic nerves, retinas and optic chiasm. Results: The received dose for each organ was less than the tolerance value (p<0.001), except for the eye lens. The normal tissue complication probability (NTCP) values for all of the organs at risk (OAR) were found insignificant. The discrepancies of calculated and measured doses for the right and left lenses were 6.35% and 6.23% (p<0.001), respectively. Conclusion: The results of this study showed based on the International Commission on Radiological Protection (ICRP) publication 118 that children with medulloblastoma cancer treated with CSI with 3D-CRT method are susceptible to cataract complication.","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43772302","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 : 2020-01-10DOI: 10.18869/ACADPUB.IJRR.18.1.185
Y. Fan, G. Qiu, Q. Pan, F. Zhang, S. Luan
Background:The influence of the limit ring on the final dose distribution in the design of the lung cancer intensity-modulated radiation therapy (IMRT) plan was studied. Materials and Methods: A total of 20 patients with lung cancer in 2017 were selected. Seven radiation beams were designed for each patient, and the limit ring width (RW) was set at 0.6, 0.8, 1.0, and 1.2 cm, respectively. The distance between the inner diameter of the limit ring and the target area (RD) was set 0.6, 0.8, 1.0, and 1.2 cm, respectively. The other parameters used in the plan were set at the same position. In addition, the conformity index (CI) and homogeneity index (HI) were calculated, and normal tissues were assessed. Results: Under the condition of the same number of radiation beams and the same distance between the limit ring and the target area, the smaller the limit ring, the better the CI of the target area and the less the HI of the target area. When the size of the limit ring was set the same, the closer the limit ring was to the target area, the better the CI of the dose in the target area, and the less the HI of the target area. Conclusions: In central lung cancer, when the target volume is approximately 800 cc, the optimal dose distribution is obtained when the RW is set at 0.8 cm and the RD is set at 0.6 cm.
{"title":"A primary study on setting the limit ring in intensity-modulated radiation therapy treatment planning in lung cancer","authors":"Y. Fan, G. Qiu, Q. Pan, F. Zhang, S. Luan","doi":"10.18869/ACADPUB.IJRR.18.1.185","DOIUrl":"https://doi.org/10.18869/ACADPUB.IJRR.18.1.185","url":null,"abstract":"Background:The influence of the limit ring on the final dose distribution in the design of the lung cancer intensity-modulated radiation therapy (IMRT) plan was studied. Materials and Methods: A total of 20 patients with lung cancer in 2017 were selected. Seven radiation beams were designed for each patient, and the limit ring width (RW) was set at 0.6, 0.8, 1.0, and 1.2 cm, respectively. The distance between the inner diameter of the limit ring and the target area (RD) was set 0.6, 0.8, 1.0, and 1.2 cm, respectively. The other parameters used in the plan were set at the same position. In addition, the conformity index (CI) and homogeneity index (HI) were calculated, and normal tissues were assessed. Results: Under the condition of the same number of radiation beams and the same distance between the limit ring and the target area, the smaller the limit ring, the better the CI of the target area and the less the HI of the target area. When the size of the limit ring was set the same, the closer the limit ring was to the target area, the better the CI of the dose in the target area, and the less the HI of the target area. Conclusions: In central lung cancer, when the target volume is approximately 800 cc, the optimal dose distribution is obtained when the RW is set at 0.8 cm and the RD is set at 0.6 cm.","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45493164","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 : 2019-12-22DOI: 10.18869/ACADPUB.IJRR.18.1.99
A. Ivković, D. Faj, S. Galic, A. Karimi, Mladen Kasabašić, H. Brkić
Background: In Southeast Europe medical accelerators are sometimes placed in small vaults originally built for Co treatment unit. In order to meet shielding requirements for high energy photon beams, the wall thickness had to be increased. Since the vaults are already limited in size, instead of adding more concrete, materials with high-Z elements were used. Limited vault size and addition of high-Z elements can contribute to the neutron dose equivalent for both medical personnel and patients. Materials and Methods: The most commonly used empirical equations for estimation of neutron dose equivalent at the maze door in the vault are by Kersey and Wu-McGinley. In order to assess accuracy of these equations, Monte Carlo (MC) simulations of various geometrical and compositional changes of vault were conducted. Neutron ambient dose equivalent (Hn(10)) was observed when dimensions of the vault walls were reduced gradually. Results: The empirical equations gave results with reasonable accuracy when vaults were of standard size. When the vault was decreased to the size of the usual Co unit vault, the most commonly used equations showed significant difference in results (up to 90%) in comparison to MC simulations. MC simulations showed that introducing different materials in shielding can change the neutron dose equivalent in vicinity of accelerators. Conclusion: For vaults limited in size, new simplified equation for neutron dose equivalent at the maze doors is presented, although performing a MC simulation of the specific vault is suggested.
{"title":"Accuracy of empirical formulas in evaluation of neutron dose equivalent inside the 60Co vaults reconstructed for medical linear accelerators","authors":"A. Ivković, D. Faj, S. Galic, A. Karimi, Mladen Kasabašić, H. Brkić","doi":"10.18869/ACADPUB.IJRR.18.1.99","DOIUrl":"https://doi.org/10.18869/ACADPUB.IJRR.18.1.99","url":null,"abstract":"Background: In Southeast Europe medical accelerators are sometimes placed in small vaults originally built for Co treatment unit. In order to meet shielding requirements for high energy photon beams, the wall thickness had to be increased. Since the vaults are already limited in size, instead of adding more concrete, materials with high-Z elements were used. Limited vault size and addition of high-Z elements can contribute to the neutron dose equivalent for both medical personnel and patients. Materials and Methods: The most commonly used empirical equations for estimation of neutron dose equivalent at the maze door in the vault are by Kersey and Wu-McGinley. In order to assess accuracy of these equations, Monte Carlo (MC) simulations of various geometrical and compositional changes of vault were conducted. Neutron ambient dose equivalent (Hn(10)) was observed when dimensions of the vault walls were reduced gradually. Results: The empirical equations gave results with reasonable accuracy when vaults were of standard size. When the vault was decreased to the size of the usual Co unit vault, the most commonly used equations showed significant difference in results (up to 90%) in comparison to MC simulations. MC simulations showed that introducing different materials in shielding can change the neutron dose equivalent in vicinity of accelerators. Conclusion: For vaults limited in size, new simplified equation for neutron dose equivalent at the maze doors is presented, although performing a MC simulation of the specific vault is suggested.","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49662647","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 : 2019-01-01DOI: 10.18869/ACADPUB.IJRR.17.2.275
J. Choi, C. H. Rim, Y. Kim, D. S. Yang
Background: Breast cancer is a common disease in radiation oncology. We evaluated the radiation dose received by breast cancer patients, an oftenneglected concern. Materials and Methods: The total effective radiation dose in 101 breast cancer patients was calculated by summing the effective doses of individual diagnostic imaging tests from the first hospital visit to the initiation of radiotherapy. The effective dose from general radiography and computed tomography (CT) was estimated using tissue-weighting factors and dose-length products. The effective dose from isotopes (18F-fluorodeoxyglucose and 99m Tc-methylene diphosphonate) was estimated from the radioactivity of each isotope using dose coefficients. The patient radiation exposures were analyzed using radiologic records in the Picture Archiving and Communication System. Results: The median duration from initial imaging to the initiation of radiotherapy was 4.5 months (range: 0.7–13.4 months). When comparing the average effective doses associated with each diagnostic modality, CT, positron emission tomography-CT, bone scanning and radiography occupied 64%, 21%, 10% and 5% of the total effective dose, respectively. Comparison of the total effective dose according to clinical factors (age, AJCC stage, T stage, N stage, operation method, and cancer location) by multivariate analysis revealed that only T stage was significantly correlated with the total effective dose (p = 0.004). The median total effective dose was 71.5 mSv (range: 11.9–131.9 mSv). Conclusion: The radiation dose received from diagnostic testing in breast cancer patients is not negligible. We need to systematically collect and manage the doses received by patients from medical procedures.
{"title":"Cumulative radiation exposure dose of diagnostic imaging studies in breast cancer patients","authors":"J. Choi, C. H. Rim, Y. Kim, D. S. Yang","doi":"10.18869/ACADPUB.IJRR.17.2.275","DOIUrl":"https://doi.org/10.18869/ACADPUB.IJRR.17.2.275","url":null,"abstract":"Background: Breast cancer is a common disease in radiation oncology. We evaluated the radiation dose received by breast cancer patients, an oftenneglected concern. Materials and Methods: The total effective radiation dose in 101 breast cancer patients was calculated by summing the effective doses of individual diagnostic imaging tests from the first hospital visit to the initiation of radiotherapy. The effective dose from general radiography and computed tomography (CT) was estimated using tissue-weighting factors and dose-length products. The effective dose from isotopes (18F-fluorodeoxyglucose and 99m Tc-methylene diphosphonate) was estimated from the radioactivity of each isotope using dose coefficients. The patient radiation exposures were analyzed using radiologic records in the Picture Archiving and Communication System. Results: The median duration from initial imaging to the initiation of radiotherapy was 4.5 months (range: 0.7–13.4 months). When comparing the average effective doses associated with each diagnostic modality, CT, positron emission tomography-CT, bone scanning and radiography occupied 64%, 21%, 10% and 5% of the total effective dose, respectively. Comparison of the total effective dose according to clinical factors (age, AJCC stage, T stage, N stage, operation method, and cancer location) by multivariate analysis revealed that only T stage was significantly correlated with the total effective dose (p = 0.004). The median total effective dose was 71.5 mSv (range: 11.9–131.9 mSv). Conclusion: The radiation dose received from diagnostic testing in breast cancer patients is not negligible. We need to systematically collect and manage the doses received by patients from medical procedures.","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67647699","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 : 2019-01-01DOI: 10.18869/ACADPUB.IJRR.17.3.513
Chien-Chin Hsu, Yi Ming Arthur Chen, Y. Tyan, Chin-Chuan Chang, Y. Chuang, Chia-Yang Lin, Ying-Fong Huang
Background: Melorheostosis has been discussed infrequently in the nuclear medicine literature. A 25-year-old female patient presented with a one-year history of bunion pain, sclerotic change and skin pigmentation on the left big toe interphalangeal joint. Ulceration, poor healing and hyperkeratoses of the wound were noted post debridement. The plain film of the left foot incidentally showed melorheostosis. Materials and Methods: Radiographs revealed cortical hyperostosis of big toe. After further evaluation by X-ray and bone scan of the left foot, the radiologic findings still indicated melorheostosis. A further Tc-99m MDP bone scan revealed extensive bone involvement in the left side of the pelvis and entire left lower extremity. Moreover, plain film whole body bone scan and MRI also revealed melorheostosis. Results: The clinical symptoms of her left big toe included interphalangeal joint callus formation, debridement, ulcer and hyperkeratoses. X-rays often reveal a pattern of thickened bone that resembles dripping candle wax, with periosteal cortical thickening, confined to sclerotomes; and can be seen apparently flowing across joints to the next bone. In the nuclear medicine image, an increase in radiotracer uptake is usually present on late phase bone scans. Conclusion: There was excellent correlation between the scintigraphic and radiographic distribution of these lesions in the following radiographs of pelvis, left femur, lower leg and MRI of the left foot. This study reported a rare case of melorheostosis affecting the big toe and reviewed the role of various imaging diagnosis of this rare bone
{"title":"Demonstration of melorheostosis on bone scan","authors":"Chien-Chin Hsu, Yi Ming Arthur Chen, Y. Tyan, Chin-Chuan Chang, Y. Chuang, Chia-Yang Lin, Ying-Fong Huang","doi":"10.18869/ACADPUB.IJRR.17.3.513","DOIUrl":"https://doi.org/10.18869/ACADPUB.IJRR.17.3.513","url":null,"abstract":"Background: Melorheostosis has been discussed infrequently in the nuclear medicine literature. A 25-year-old female patient presented with a one-year history of bunion pain, sclerotic change and skin pigmentation on the left big toe interphalangeal joint. Ulceration, poor healing and hyperkeratoses of the wound were noted post debridement. The plain film of the left foot incidentally showed melorheostosis. Materials and Methods: Radiographs revealed cortical hyperostosis of big toe. After further evaluation by X-ray and bone scan of the left foot, the radiologic findings still indicated melorheostosis. A further Tc-99m MDP bone scan revealed extensive bone involvement in the left side of the pelvis and entire left lower extremity. Moreover, plain film whole body bone scan and MRI also revealed melorheostosis. Results: The clinical symptoms of her left big toe included interphalangeal joint callus formation, debridement, ulcer and hyperkeratoses. X-rays often reveal a pattern of thickened bone that resembles dripping candle wax, with periosteal cortical thickening, confined to sclerotomes; and can be seen apparently flowing across joints to the next bone. In the nuclear medicine image, an increase in radiotracer uptake is usually present on late phase bone scans. Conclusion: There was excellent correlation between the scintigraphic and radiographic distribution of these lesions in the following radiographs of pelvis, left femur, lower leg and MRI of the left foot. This study reported a rare case of melorheostosis affecting the big toe and reviewed the role of various imaging diagnosis of this rare bone","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67647767","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 : 2018-10-10DOI: 10.18869/ACADPUB.IJRR.16.4.395
Makoto Ito, T. Kawamura, Y. Mori, Toshie Mori, A. Takeuchi, Y. Oshima, Kazuhiko Nakamura, T. Aoyama, N. Kaneda, T. Ishiguchi, S. Mizumatsu
Background: Several high-precision stereotactic radiation therapy modalities are currently used in clinical settings. We aimed to evaluate whether the CyberKnife (CK) or TrueBeam (TB) radiation treatment systems were more appropriate for treating targets of various morphologies according to the physical properties of each device. Materials and Methods: Spheres (diameter = 5–50 mm), as well as triangular prisms and cubes (length of a side = 10–50 mm), were used as virtual targets for each treatment delivery system. A phantom with dosimetry film was irradiated to evaluate the flatness and gradient of the radiation treatment from each modality. Results: The homogeneity index (HI) for the spherical targets was significantly higher (dose distribution was more homogeneous) using the TB than when using the CK (1.9 vs. 1.4; p = 0.002). There were no significant differences between treatment modalities in the HI for more complex shapes. The HI increased monotonically as the virtual target diameter increased for the CK (p = 0.048). The flatness parameter was lower for the TB than for the CK (1.4 vs. 1.1; p < 0.001). Conclusion: The CK is particularly robust for delivering therapeutic radiation to small targets, while the TB is more suitable for targets with a simple shape or when the HI is a critical treatment factor.
{"title":"Dose distributions of high-precision radiotherapy treatment: A comparison between the CyberKnife and TrueBeam systems","authors":"Makoto Ito, T. Kawamura, Y. Mori, Toshie Mori, A. Takeuchi, Y. Oshima, Kazuhiko Nakamura, T. Aoyama, N. Kaneda, T. Ishiguchi, S. Mizumatsu","doi":"10.18869/ACADPUB.IJRR.16.4.395","DOIUrl":"https://doi.org/10.18869/ACADPUB.IJRR.16.4.395","url":null,"abstract":"Background: Several high-precision stereotactic radiation therapy modalities are currently used in clinical settings. We aimed to evaluate whether the CyberKnife (CK) or TrueBeam (TB) radiation treatment systems were more appropriate for treating targets of various morphologies according to the physical properties of each device. Materials and Methods: Spheres (diameter = 5–50 mm), as well as triangular prisms and cubes (length of a side = 10–50 mm), were used as virtual targets for each treatment delivery system. A phantom with dosimetry film was irradiated to evaluate the flatness and gradient of the radiation treatment from each modality. Results: The homogeneity index (HI) for the spherical targets was significantly higher (dose distribution was more homogeneous) using the TB than when using the CK (1.9 vs. 1.4; p = 0.002). There were no significant differences between treatment modalities in the HI for more complex shapes. The HI increased monotonically as the virtual target diameter increased for the CK (p = 0.048). The flatness parameter was lower for the TB than for the CK (1.4 vs. 1.1; p < 0.001). Conclusion: The CK is particularly robust for delivering therapeutic radiation to small targets, while the TB is more suitable for targets with a simple shape or when the HI is a critical treatment factor.","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46044008","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 : 2018-07-10DOI: 10.18869/ACADPUB.IJRR.16.2.279
H. Won, J. Chung, K. Eom, D. Hwang, S. Kang, T. Suh
Background: The purpose of this study was to evaluate the feasibility of a multipurpose quality assurance (QA) phantom for pretreatment verification of volumetric modulated arc therapy (VMAT). Materials and Methods: The QA phantom was constructed with polymethyl methacrylate (PMMA) to perform relative dosimetry using EBT3 film and MapCHECK, as well as absolute dosimetry using an ionization chamber. The QA phantom was constructed to perform relative dosimetry using EBT3 film and MapCHECK, as well as the absolute dosimetry using ionization chamber. In order to verify the pretreatment plans, 25 patients treated with VMAT were selected. The pretreatment plans were calculated in the Eclipse treatment planning system using the Acuros XB dose calculation algorithm and CT images for the QA phantom, with the same beam setup and monitor units (MUs) as those for patient treatment. All plans were delivered to the Varian TrueBeam accelerator equipped with a high-definition multi-leaf collimator. Results: The multi-purpose QA phantom is developed for convenient VMAT dose verification. By using the QA phantom, all 25 cases passed ±3% acceptability criteria in absolute dosimetry with an ionization chamber for pretreatment verification. The relative dosimetry using EBT3 film and MapCHECK system also showed high agreement of more than 90% for 2%/2-mm and 3%/3-mm criteria. Conclusion: The results of this study demonstrated the good multipurpose capabilities of the phantom for the absolute and relative dosimetry. Therefore, the developed multi-purpose QA phantom was applied in our institution for routine VMRT dose verification.
{"title":"Feasibility study of multi-purpose quality assurance phantom for pretreatment verification of volumetric modulated arc therapy","authors":"H. Won, J. Chung, K. Eom, D. Hwang, S. Kang, T. Suh","doi":"10.18869/ACADPUB.IJRR.16.2.279","DOIUrl":"https://doi.org/10.18869/ACADPUB.IJRR.16.2.279","url":null,"abstract":"Background: The purpose of this study was to evaluate the feasibility of a multipurpose quality assurance (QA) phantom for pretreatment verification of volumetric modulated arc therapy (VMAT). Materials and Methods: The QA phantom was constructed with polymethyl methacrylate (PMMA) to perform relative dosimetry using EBT3 film and MapCHECK, as well as absolute dosimetry using an ionization chamber. The QA phantom was constructed to perform relative dosimetry using EBT3 film and MapCHECK, as well as the absolute dosimetry using ionization chamber. In order to verify the pretreatment plans, 25 patients treated with VMAT were selected. The pretreatment plans were calculated in the Eclipse treatment planning system using the Acuros XB dose calculation algorithm and CT images for the QA phantom, with the same beam setup and monitor units (MUs) as those for patient treatment. All plans were delivered to the Varian TrueBeam accelerator equipped with a high-definition multi-leaf collimator. Results: The multi-purpose QA phantom is developed for convenient VMAT dose verification. By using the QA phantom, all 25 cases passed ±3% acceptability criteria in absolute dosimetry with an ionization chamber for pretreatment verification. The relative dosimetry using EBT3 film and MapCHECK system also showed high agreement of more than 90% for 2%/2-mm and 3%/3-mm criteria. Conclusion: The results of this study demonstrated the good multipurpose capabilities of the phantom for the absolute and relative dosimetry. Therefore, the developed multi-purpose QA phantom was applied in our institution for routine VMRT dose verification.","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47449536","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 : 2018-04-15DOI: 10.18869/ACADPUB.IJRR.16.2.217
G. Jelodar, A. Akbari, P. Parvaeei, S. Nazifi
Background: Radio frequency wave (RFW) generated by mobile phones and wireless communica on systems has been reported to cause adverse effects on reproduc ve func on, vision and hematological parameters, possibly through oxida ve stress. The aim of this study was to evaluate the effect of RFW generated bybase transceiver sta on BTS on oxida ve stress in tes s, eye and erythrocyte, and the prophylac c effect of vitamin E by measuring the an oxidant enzymes ac vity, including: glutathione peroxidase (GPx), superoxide dismutase (SOD) and catalase (CAT), and lipid proxida on. Materials and Methods: Thirty-two adult male Sprague–Dawley rats were randomly divided into four groups and treated daily for 45 days as follows: control, treatment control (vitamin E 200 mg/kg of body weight/ day by gavage), sham exposed group (exposed to 900 MHz RFW), and treatment group (received vitamin E and exposed to RFW). Control and treatment control groups were not exposed and were only given the vehicle, i.e., dis lled water. On the last day of the study, all the rats were sacrificed and their testes, eyes and erythrocyte were collected and used for measurement of an oxidant enzymes ac vity and lipid peroxida on. Results: Exposure to RFW in the sham exposed group decreased an oxidant enzymes ac vity and increased lipid peroxida on compared to both control groups (p<0.05). In the treatment group, vitamin E improved an oxidant enzymes ac vity and reduced lipid peroxida on compared to the sham exposed group (p<0.05). Conclusion: RFW causes oxida ve stress in eye, tes s and erythrocytes and vitamin E improved oxida ve stress in these ssues.
{"title":"Vitamin E protects rat testis, eye and erythrocyte from oxidative stress during exposure to radiofrequency wave generated by a BTS antenna model","authors":"G. Jelodar, A. Akbari, P. Parvaeei, S. Nazifi","doi":"10.18869/ACADPUB.IJRR.16.2.217","DOIUrl":"https://doi.org/10.18869/ACADPUB.IJRR.16.2.217","url":null,"abstract":"Background: Radio frequency wave (RFW) generated by mobile phones and wireless communica on systems has been reported to cause adverse effects on reproduc ve func on, vision and hematological parameters, possibly through oxida ve stress. The aim of this study was to evaluate the effect of RFW generated bybase transceiver sta on BTS on oxida ve stress in tes s, eye and erythrocyte, and the prophylac c effect of vitamin E by measuring the an oxidant enzymes ac vity, including: glutathione peroxidase (GPx), superoxide dismutase (SOD) and catalase (CAT), and lipid proxida on. Materials and Methods: Thirty-two adult male Sprague–Dawley rats were randomly divided into four groups and treated daily for 45 days as follows: control, treatment control (vitamin E 200 mg/kg of body weight/ day by gavage), sham exposed group (exposed to 900 MHz RFW), and treatment group (received vitamin E and exposed to RFW). Control and treatment control groups were not exposed and were only given the vehicle, i.e., dis lled water. On the last day of the study, all the rats were sacrificed and their testes, eyes and erythrocyte were collected and used for measurement of an oxidant enzymes ac vity and lipid peroxida on. Results: Exposure to RFW in the sham exposed group decreased an oxidant enzymes ac vity and increased lipid peroxida on compared to both control groups (p<0.05). In the treatment group, vitamin E improved an oxidant enzymes ac vity and reduced lipid peroxida on compared to the sham exposed group (p<0.05). Conclusion: RFW causes oxida ve stress in eye, tes s and erythrocytes and vitamin E improved oxida ve stress in these ssues.","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47839516","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 : 2018-04-10DOI: 10.18869/ACADPUB.IJRR.16.2.225
Y. Zhuang, Wei Huang, Yuzhen Shi, Genji Bo, D. Lu, J. Zhang, D. Kong, B. Wang
Background: Prospec vely electrocardiography (ECG)-triggered high-pitch spiral coronary computed tomography angiography (CCTA) is a unique scan mode for dual -source CT (DSCT). Our reports aim to compare image quality and radia on dose of CCTA using high-pitch spiral or sequen al acquisi on mode in pa ents with low and stable heart rates. Materials and Methods: Pa ents with low and stable heart rates (HR) (HR ≤ 70 beats per minute [bpm]; heart rate variability [HRV] < 10 bpm) were randomly assigned to high-pitch spiral mode (group A; n = 80) or sequen al acquisi on mode (group B; n = 80). Image quality scores, image noise, effec ve radia on dose and influencing factors on image quality were assessed. Results: Mean image quality scores were 1.51 ± 0.32 and 1.70 ± 0.38 for groups A and B (P < 0.05), respec vely. Image noises of the two groups were 19.05±4.70 Hu and 27.21±8.88 Hu (P < 0.05). Contrast media cost in group A was lower than group B (P < 0.05). No sta s cal difference was found in the rate of diagnos c pa ents between the two groups (P = 0.416). The es mated radia on dose of group A was 26.0% reduced compared with group B (0.74 ± 0.34 mSv vs. 1.00 ± 0.48 mSv, P < 0.05). Conclusion: In pa ents with regular and low heart rates, the prospec vely high-pitch spiral acquisi on mode can reduce radia on dose and contrast media cost while maintaining image quality compared with the prospec vely sequen al mode.
背景:前瞻性心电图(ECG)触发的高间距螺旋冠状动脉CT血管造影(CCTA)是一种独特的双源CT (DSCT)扫描模式。我们的报告旨在比较在低心率和稳定心率的患者中使用高音调螺旋或顺序采集模式CCTA的图像质量和辐射剂量。材料与方法:低稳定心率(HR)患者(HR≤70次/分钟[bpm];心率变异性[HRV] < 10 bpm]的患者随机分为高音调螺旋模式(A组;n = 80)或顺序采集模式(B组;N = 80)。评估图像质量评分、图像噪声、辐射对剂量的影响以及影响图像质量的因素。结果:A组和B组的平均图像质量评分分别为1.51±0.32和1.70±0.38 (P < 0.05)。两组图像噪声分别为19.05±4.70 Hu和27.21±8.88 Hu (P < 0.05)。A组造影剂成本低于B组(P < 0.05)。两组患儿诊断率差异无统计学意义(P = 0.416)。与B组相比，A组的辐射剂量降低26.0%(0.74±0.34 mSv vs. 1.00±0.48 mSv, P < 0.05)。结论:在正常心率和低心率的患者中，与序贯模式相比，准高频螺旋采集模式在保持图像质量的同时，可减少辐射剂量和造影剂成本。
{"title":"Prospective-triggered high-pitch spiral versus sequential dual-source CT coronary angiography: comparison of image quality and radiation dose","authors":"Y. Zhuang, Wei Huang, Yuzhen Shi, Genji Bo, D. Lu, J. Zhang, D. Kong, B. Wang","doi":"10.18869/ACADPUB.IJRR.16.2.225","DOIUrl":"https://doi.org/10.18869/ACADPUB.IJRR.16.2.225","url":null,"abstract":"Background: Prospec vely electrocardiography (ECG)-triggered high-pitch spiral coronary computed tomography angiography (CCTA) is a unique scan mode for dual -source CT (DSCT). Our reports aim to compare image quality and radia on dose of CCTA using high-pitch spiral or sequen al acquisi on mode in pa ents with low and stable heart rates. Materials and Methods: Pa ents with low and stable heart rates (HR) (HR ≤ 70 beats per minute [bpm]; heart rate variability [HRV] < 10 bpm) were randomly assigned to high-pitch spiral mode (group A; n = 80) or sequen al acquisi on mode (group B; n = 80). Image quality scores, image noise, effec ve radia on dose and influencing factors on image quality were assessed. Results: Mean image quality scores were 1.51 ± 0.32 and 1.70 ± 0.38 for groups A and B (P < 0.05), respec vely. Image noises of the two groups were 19.05±4.70 Hu and 27.21±8.88 Hu (P < 0.05). Contrast media cost in group A was lower than group B (P < 0.05). No sta s cal difference was found in the rate of diagnos c pa ents between the two groups (P = 0.416). The es mated radia on dose of group A was 26.0% reduced compared with group B (0.74 ± 0.34 mSv vs. 1.00 ± 0.48 mSv, P < 0.05). Conclusion: In pa ents with regular and low heart rates, the prospec vely high-pitch spiral acquisi on mode can reduce radia on dose and contrast media cost while maintaining image quality compared with the prospec vely sequen al mode.","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41272744","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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