基于钙化点的锥形束CT校准在前列腺癌图像引导放疗中应用研究  

Application of cone beam CT calibration based on calcification point in image guided radiotherapy for prostate cancer

作　　者：王丹镭 赵改花[2] 田龙[1] 胡逸民[3] WANG Danlei;ZHAO Gaihua;TIAN Long;HU Yimin(Department of Radiotherapy,The First Affiliated Hospital of Hebei North University,Zhangjiakou,Hebei,075000,China;Department of Radiotherapy,Handan Central Hospital;Department of Radiotherapy,Cancer Hospital Chinese Academy of Medical Sciences)

机构地区：[1]河北北方学院附属第一医院放疗科,河北张家口075000 [2]邯郸市中心医院放疗科 [3]中国医学科学院肿瘤医院放疗科

出　　处：《临床泌尿外科杂志》2023年第4期277-280,287,共5页Journal of Clinical Urology

基　　金：张家口市重点研发计划项目(No:1921002B)。

摘　　要：目的:以基于骨骼的锥形束CT(CBCT)校准为金标准,评价前列腺癌(PCa)图像引导放疗(IGRT)中基于钙化点的CBCT校准应用的可行性。方法:筛选符合纳排标准的PCa患者30例,接受每周2次治疗前基于骨骼和钙化点的CBCT校准。首先,采用自研算法计算计划CT和首次CBCT3个方向图像上钙化点可探测性分数。图像上钙化点可探测性分数低于0.260分的患者退出试验。之后,以剩余患者基于骨骼的CBCT校准数据为金标准,采用Bland-Altman法分析2种校准方法的数据一致性。结果:4例患者计划CT或首次CBCT图像存在钙化点可探测性分数不达标情况并退出试验。其余26例患者共接受了364次CBCT扫描,其中基于骨骼的校准数据为,左右方向:(0.11±0.07)cm、头脚方向:(0.18±0.13)cm、腹背方向:(0.23±0.22)cm;基于钙化点的校准数据为,左右方向:(0.13±0.11)cm、头脚方向:(0.22±0.19)cm、腹背方向:(0.30±0.25)cm。Bland-Altman分析结果显示,2种校准方法的数据在3个方向上一致性良好。结论:2种校准方法的数据差异较小且一致性良好,在特定条件下基于钙化点的CBCT校准在PCa IGRT中应用具有可行性。Objective To evaluate the feasibility of cone beam CT(CBCT)calibration based on calcification point in image guided radiotherapy(IGRT)for prostate cancer(PCa),taking the CBCT calibration based on bone as the gold standard.Methods Thirty patients with PCa who met the inclusion and exclusion criteria were selected and received CBCT calibration based on bone and calcification point before treatment twice a week.Firstly,the self-developed algorithm was used to calculate the detectability scores of calcification points in three directions on the planning CT and the first CBCT images.Patients with calcification point detectability scores less than 0.260 on the images withdrew from the trial.Then,taking the CBCT calibration data based on bone from the remaining patients as the gold standard,the Bland Altman method was used to analyze the data consistency of the two calibration methods.Results The detectability scores of calcification points on planning CT or first CBCT images from 4 patients were not up to standard and they withdrew from the trial.The remaining 26 patients received 364 CBCT scans,of which the calibration data based on bone were as follows,left-right direction:(0.11±0.07)cm,superior-inferior direction:(0.18±0.13)cm,anterior-posterior direction:(0.23±0.22)cm.The calibration data based on calcification point were as follows,left-right direction:(0.13±0.11)cm,superior-inferior direction:(0.22±0.19)cm,anterior-posterior direction:(0.30±0.25)cm.The Bland Altman analysis results showed that the data of the two calibration methods were consistent in three directions.Conclusion The data of the two calibration methods had little difference and good consistency.CBCT calibration based on calcification point was feasible in PCa IGRT under specific conditions.

关 键 词：前列腺癌 图像引导放疗 CBCT 校准 钙化点 

分 类 号：R737.25[医药卫生—肿瘤]