A. Rostami, S. Naseri, M. Momennezhad, H. Zare, K. Anvari, H. R. S. Badkhor
{"title":"基于磁共振放射治疗的新型大视场体对磁共振图像几何畸变的评价","authors":"A. Rostami, S. Naseri, M. Momennezhad, H. Zare, K. Anvari, H. R. S. Badkhor","doi":"10.52547/IJRR.18.4.733","DOIUrl":null,"url":null,"abstract":"Background: The magnetic resonance imaging (MRI)-based radiotherapy planning method have been considered in recent years because of the advantages of MRI and the problems of planning with two images modality. The first step in MRI-based radiotherapy is to evaluate magnetic resonance (MR) images geometric distortion. Therefore, the present study aimed to evaluate system related geometric distortion by a new large field of view phantom. Materials and Methods: A homemade phantom with Perspex sheets and plastic pipes containing water was built for evaluating MR images distortion. The phantom size is 48×48×37 cm and includes 325 water pipes. The study evaluated four different protocols from a 60 cm bore MAGNETOM® Symphony Syngo 1.5 T (Siemens). Results: It was found that the amount of distortion for all protocols is under 2 mm for the radial distances less than 10 cm (field of view (FOV) = 20 cm), but distortion increased in radial distances greater than 10 cm, and reached about 5 cm for radial distances greater than 25 cm. Conclusion: Geometric distortion of each MR scanner has been shown to be dependent on the radio frequency (RF) sequence pulse (Spin echo or Gradient echo) and image parameters (echo time (TE), repetition time (TR), and receiver band-width)). The geometric distortion could be ignored for the FOV<20 cm (for the head region), and must be evaluated and corrected for more FOVs before the MR only radiotherapy.","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"2020-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Geometric distortion evaluation of magnetic resonance images by a new large field of view phantom for magnetic resonance based radiotherapy purposes\",\"authors\":\"A. Rostami, S. Naseri, M. Momennezhad, H. Zare, K. Anvari, H. R. S. Badkhor\",\"doi\":\"10.52547/IJRR.18.4.733\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Background: The magnetic resonance imaging (MRI)-based radiotherapy planning method have been considered in recent years because of the advantages of MRI and the problems of planning with two images modality. The first step in MRI-based radiotherapy is to evaluate magnetic resonance (MR) images geometric distortion. Therefore, the present study aimed to evaluate system related geometric distortion by a new large field of view phantom. Materials and Methods: A homemade phantom with Perspex sheets and plastic pipes containing water was built for evaluating MR images distortion. The phantom size is 48×48×37 cm and includes 325 water pipes. The study evaluated four different protocols from a 60 cm bore MAGNETOM® Symphony Syngo 1.5 T (Siemens). Results: It was found that the amount of distortion for all protocols is under 2 mm for the radial distances less than 10 cm (field of view (FOV) = 20 cm), but distortion increased in radial distances greater than 10 cm, and reached about 5 cm for radial distances greater than 25 cm. Conclusion: Geometric distortion of each MR scanner has been shown to be dependent on the radio frequency (RF) sequence pulse (Spin echo or Gradient echo) and image parameters (echo time (TE), repetition time (TR), and receiver band-width)). The geometric distortion could be ignored for the FOV<20 cm (for the head region), and must be evaluated and corrected for more FOVs before the MR only radiotherapy.\",\"PeriodicalId\":14498,\"journal\":{\"name\":\"Iranian Journal of Radiation Research\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2020-10-10\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Iranian Journal of Radiation Research\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.52547/IJRR.18.4.733\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q4\",\"JCRName\":\"Health Professions\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Iranian Journal of Radiation Research","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.52547/IJRR.18.4.733","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"Health Professions","Score":null,"Total":0}
Geometric distortion evaluation of magnetic resonance images by a new large field of view phantom for magnetic resonance based radiotherapy purposes
Background: The magnetic resonance imaging (MRI)-based radiotherapy planning method have been considered in recent years because of the advantages of MRI and the problems of planning with two images modality. The first step in MRI-based radiotherapy is to evaluate magnetic resonance (MR) images geometric distortion. Therefore, the present study aimed to evaluate system related geometric distortion by a new large field of view phantom. Materials and Methods: A homemade phantom with Perspex sheets and plastic pipes containing water was built for evaluating MR images distortion. The phantom size is 48×48×37 cm and includes 325 water pipes. The study evaluated four different protocols from a 60 cm bore MAGNETOM® Symphony Syngo 1.5 T (Siemens). Results: It was found that the amount of distortion for all protocols is under 2 mm for the radial distances less than 10 cm (field of view (FOV) = 20 cm), but distortion increased in radial distances greater than 10 cm, and reached about 5 cm for radial distances greater than 25 cm. Conclusion: Geometric distortion of each MR scanner has been shown to be dependent on the radio frequency (RF) sequence pulse (Spin echo or Gradient echo) and image parameters (echo time (TE), repetition time (TR), and receiver band-width)). The geometric distortion could be ignored for the FOV<20 cm (for the head region), and must be evaluated and corrected for more FOVs before the MR only radiotherapy.
期刊介绍:
Iranian Journal of Radiation Research (IJRR) publishes original scientific research and clinical investigations related to radiation oncology, radiation biology, and Medical and health physics. The clinical studies submitted for publication include experimental studies of combined modality treatment, especially chemoradiotherapy approaches, and relevant innovations in hyperthermia, brachytherapy, high LET irradiation, nuclear medicine, dosimetry, tumor imaging, radiation treatment planning, radiosensitizers, and radioprotectors. All manuscripts must pass stringent peer-review and only papers that are rated of high scientific quality are accepted.