支气管镜智能导航植入可回收金标在射波刀同步呼吸追踪可行性的体模研究

目的 探究支气管镜智能导航下植入可回收金标在射波刀同步呼吸追踪的可行性。方法 在充气状态下获取经反腐处理的生物猪肺CT影像,利用智能导航软件在左、右肺叶分别设计8例模拟肿瘤病灶位点。设置多痰支气管环境组4例和湿润支气管环境组4例,根据射波刀金标植入原则,将智能规划后的32个可回收金标经支气管植入到每个模拟肿瘤病灶周围。模拟呼气末状态,再次扫描生物猪肺获取植入的金标CT影像,并记录成功植入金标数。利用射波刀计划系统(Multiplan v4.6)设计8个可执行的Synchrony治疗计划,对模拟呼吸运动的生物猪肺进行施照,记录可追踪金标数。施照后通过支气管镜取回已植入的可回收金标,记录成功回收金标个数。提取射波刀log文件中的治疗数据进行追踪数据整理分析,统计整个治疗过程的平移修正偏差、旋转修正偏差以及刚性误差。结果 实验过程中没有出现可回收金标滑脱、掉落等情况。支气管镜智能导航引导下成功植入与取出可回收金标32个,植入成功率与回收成功率均为100%。射波刀施照过程中金标追踪率为100%,刚性误差均＜5 mm,治疗后统计射波刀log文件数据,多痰支气管环境组与湿润支气管环境组在左右方向平移偏差、左右方向旋转偏差、俯仰方向旋转偏差的差异均无统计学意义(P>0.05)。多痰支气管环境组在前后方向平移偏差(Z=-3.57, P<0.01)及头脚方向平移偏差(Z=-2.53,P<0.05)稍高于湿润支气管环境组,而平旋方向旋转偏差(Z=-3.88,P<0.01)及刚性误差(Z=-3.32,P<0.01)均低于湿润支气管环境组。结论 经支气管镜智能导航植入可回收金标技术可行,可回收金标在体模支气管内稳定性好,且射波刀追踪精度可满足临床要求,有较好的临床应用与教学应用前景。

A phantom study on the feasibility of recoverable fiducial marker implantation guided using the intelligent navigation bronchoscopy technology in Cyberknife Synchrony-based respiratory tracking

Objective To explore the feasibility of recoverable fiducial marker implantation guided using the intelligent navigation bronchoscopy technology in the Cyberknife Synchrony-based respiratory tracking.Methods CT scans of an inflatable pig lung after anti-rot processing were obtained. Then, eight simulated tumor lesion sites were designed in the left and right lung lobes using intelligent navigation software, with four classified as the sputum bronchial environment group and four classified as the wet bronchial environment group. Based on the implantation principle of Cyberknife fiducial markers, 32 recoverable fiducial markers were implanted around various simulated tumor lesions via bronchus under intelligent guidance. Then, the end-expiratory state of the pig lung was simulated, the pig lung was scanned again to obtain CT images of the implanted recoverable fiducial markers, and the number of successfully implanted fiducial markers was recorded. Eight deliverable Synchrony treatment protocols were designed using the Cyberknife planning system (Multiplan v4.6), and then the pig lung with simulated respiratory movements was exposed to radiation. After radiation, the implanted recoverable fiducial markers were retrieved using the bronchoscopy technique, and the number of successfully retrieved fiducial markers was recorded. Moreover, the translational errors, rotational errors, and rigid body errors were extracted from the Cyberknife log file and analyzed.Results No recoverable fiducial markers slipped or fell during the experiment. Thirty-two recoverable fiducial markers were successfully implanted and recovered under the guidance of intelligent navigation bronchoscopy, with implantation and recovery success rates of both 100%. Moreover, the tracking rate and rigid body errors of the fiducial markers were 100% and less than 5 mm, respectively. The data from the Cyberknife log file indicated that there was no significant difference between the sputum bronchial environment group and the wet bronchial environment group in the translational errors in the left-right direction, the rotational errors in the roll direction, and the rotational errors in the pitch direction (P>0.05). Compared to the wet bronchial environment group, the sputum bronchial environment group had slightly higher translational errors in front-back (Z=-3.57, P<0.01) and cranio-caudal (Z=-2.53, P<0.05) directions, lower rotational errors along the yaw axis (Z = -3.88, P < 0.01), and lower rigid body error (Z=-3.32, P<0.01), and the differences were all statistically significant.Conclusions The recoverable fiducial marker implantation guided using the intelligent navigation bronchoscopy technology is feasible. Recoverable fiducial markers are stable in the bronchus of the phantom, and the Cyberknife tracking precision can meet clinical requirements. Therefore, the recoverable fiducial marker implantation guided using the intelligent navigation bronchoscopy technology has promising prospects in clinical and teaching applications.