{"title":"Repeatability of rectal cancer apparent diffusion coefficient measurements on a 1.5 T MR-linac","authors":"Hidde Eijkelenkamp , Guus Grimbergen , Brigid McDonald , Reijer Rutgers , Tim Schakel , Casper Beijst , Marielle Philippens , Gert Meijer , Martijn Intven","doi":"10.1016/j.phro.2025.100720","DOIUrl":null,"url":null,"abstract":"<div><div>The repeatability of the apparent diffusion coefficient (ADC) during radiotherapy for rectal cancer on a 1.5 T MR-linac was investigated by acquiring two sequential diffusion-weighted imaging (DWI) sequences at each fraction. In 109 treatment sessions involving 22 patients, tumors were separately delineated on the b500 images. ADC maps were generated with all b-values (0, 30, 150, and 500 s/mm<sup>2</sup>) on the MR-linac, and the median ADC values were used in Bland-Altman analyses. A relative repeatability coefficient of 17.0 % was determined, providing a threshold to differentiate between measurement variability and true treatment response. This threshold can be used for potential response monitoring and personalized treatment adjustments.</div></div>","PeriodicalId":36850,"journal":{"name":"Physics and Imaging in Radiation Oncology","volume":"33 ","pages":"Article 100720"},"PeriodicalIF":3.3000,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Physics and Imaging in Radiation Oncology","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2405631625000259","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2025/1/30 0:00:00","PubModel":"Epub","JCR":"Q2","JCRName":"ONCOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
The repeatability of the apparent diffusion coefficient (ADC) during radiotherapy for rectal cancer on a 1.5 T MR-linac was investigated by acquiring two sequential diffusion-weighted imaging (DWI) sequences at each fraction. In 109 treatment sessions involving 22 patients, tumors were separately delineated on the b500 images. ADC maps were generated with all b-values (0, 30, 150, and 500 s/mm2) on the MR-linac, and the median ADC values were used in Bland-Altman analyses. A relative repeatability coefficient of 17.0 % was determined, providing a threshold to differentiate between measurement variability and true treatment response. This threshold can be used for potential response monitoring and personalized treatment adjustments.
在1.5 T MR-linac上，通过获得每个分数的两个连续扩散加权成像（DWI）序列，研究了直肠癌放疗期间表观扩散系数（ADC）的可重复性。在涉及22例患者的109次治疗中，肿瘤分别在b500图像上勾画。在MR-linac上生成所有b值（0、30、150和500 s/mm2）的ADC图，并在Bland-Altman分析中使用中位数ADC值。测定的相对重复性系数为17.0%，为区分测量变异性和真实治疗反应提供了一个阈值。该阈值可用于潜在反应监测和个性化治疗调整。
京公网安备 11010802042870号
京ICP备2023020795号-1
分享
求助内容：
应助结果提醒方式：
扫码关注我们
