新型TiGRT IVS系统引导肺癌调强放射治疗摆位研究

目的:以锥形束CT(cone beam CT,CBCT)配准结果为参考,验证TiGRT IVS系统的在线校位精度,从而验证其临床有效性及可行性.方法:选择2019年10月至2020年2月在陆军军医大学第二附属医院全军肿瘤研究所放疗中心接受调强放射治疗的30例肺癌患者.首次摆位时行TiGRT IVS系统和CBCT位置验证...

Study on new-TiGRT-IVS-guided setup for intensity-modulated radiation therapy of lung cancer

Objective To verify the on-line registration accuracy of TiGRT IVS with cone beam CT(CBCT)registration results used as the references,so as to validate the clinical efficacy and feasibility of TiGRT IVS.Methods Thirty lung cancer patients who received intensity-modulated radiation therapy(IMRT)at Radiotherapy Center of the PLA Cancer Institute of the Second Affiliated Hospital of Army Military Medical University from October 2019 to February 2020 were selected as the subjects.TiGRT IVS and CBCT location verifications were executed in the first setup,which was carried out once a week for the patients with conventional dose fractionation and every time when the treatment was performed for the ones with large dose fractionation.The images were registered with those by digitally reconstructed radiograph(DRR).There were two kinds of IVS-A and IVS-B methods for TiGRT IVS registration.IVS-A method realized bony registration for the vertebral body and ribs,then based on the results IVS-B method used the trachea as the characteristic structure for the registration of posteroanterior images.The results of IVS-A and IVS-B registration were compared with those by CBCT to observe the efficacy of TiGRT IVS for the analysis and control of the setup error of lung cancer IMRT.Results The time required for registration was(69±12),(54±8)and(112±14)s for IVS-A,IVS-B and CBCT respectively,with TiGRT IVS taking less time for registration than CBCT and IVS-B taking less time than IVS-A.TiGRT IVS had the setup errors mainly concentrated in the range of 0-5 mm,with few errors above 8 mm.The setup errors obtained with TiGRT IVS and CBCT were only statistically different in the Vrt(anterior-posterior)direction of the patient,which met the requirements of the clinical criteria.TiGRT IVS had significant difference with CBCT when used for registration for one patient with high-dose segmentation in the Lng(head-foot)direction in the first 1-7 treatment fractionations.Conclusion TiGRT IVS can effectively detect the setup error of IMRT in patients with lung cancer.Trachea can be selected as the characteristic structure of registration in posteroanterior images.CBCT can be combined to observe the location of the target area during image guidance of patients with large dose segmentation.[Chinese Medical Equipment Journal,2021,42(2):43-46,98]