三维可视化系统评估微波消融治疗原发性肝癌疗效的应用价值

Application value of three-dimensional visualization system in evaluating efficacy of microwave ablation in treatment of primary liver cancer

背景肿瘤局部进展(local tumor progress,LTP)是热消融治疗原发性肝癌的主要问题。治疗未达到安全消融边界(safety ablation margin,SAM)是发生LTP的重要危险因素。本团队自主研发的三维可视化手术系统,可进行术前规划以辅助消融治疗,还可通过三维重建及配准融合,对肿瘤消融疗效进行精准、量化的评估。目的对比三维可视化配准与二维增强MRI两种方式评估原发性肝癌消融疗效的准确率,验证三维可视化配准对消融疗效评估的准确率。方法回顾性分析解放军总医院第一医学中心介入超声科2017年6月-2019年6月收治的137例超声引导消融治疗原发性肝癌的患者临床资料,使用两种方法分别对137例患者术前、术后增强MRI进行肿瘤消融疗效评估,分析消融灶是否完全覆盖肿瘤病灶及是否达到安全消融边界。SAM是指超过原发性肿瘤5 mm的区域,在消融治疗时应将其灭活,消融疗效按SAM分为以下三级:A_(0),SAM>5 mm;A_(1),0 mm<SAM<5 mm;A_(2),SAM<0 mm。其中A_(0)、A_(1)为肿瘤完全灭活,A_(2)为肿瘤灭活不全。三维可视化组使用三维重建及非刚性配准融合的方法,二维增强MRI组使用图像并列对比的方法。结果三维可视化组消融疗效评估结果:A_(0)91例,A_(1)26例,A_(2)20例;二维增强MRI组消融疗效评估结果:A_(0)109例,A_(1)17例,A_(2)11例;两组方法疗效评估结果差异有统计学意义(P=0.041)。随访结果显示22例患者发生LTP,其中三维可视化评估为A_(1)组出现2例,A_(2)组20例全部发生;二维增强MRI评估为A_(1)组出现11例,A_(2)组11例全部发生;差异有统计学意义(P=0.003)。三维可视化评估预测LTP的准确率(98.5%vs 92.0%)、敏感度(90.9%vs 50.0%)、阴性预测值(98.3%vs 90.6%)均优于二维增强MRI评估(P均<0.05),特异性和阳性预测值两组均为100%。结论三维可视化技术对消融疗效的评估结果敏感度高,相比二维增强MRI更加精准、量化地评估了肿瘤消融疗效,对LTP有较高的预测价值。

Background Local tumor progression(LTP)is a major problem in thermal ablation therapy for primary liver cancer.Treatment without reaching the safety ablation margin(SAM)is an important risk factor for LTP.The 3D visualization surgical system independently developed by our team can perform preoperative planning to assist ablation treatment,and it can also accurately and quantitatively evaluate the efficacy of tumor ablation through 3D reconstruction and registration fusion.Objective To compare the accuracy of 3D visualization registration versus 2D enhanced MRI in evaluating the ablation efficacy of primary liver cancer,so as to verify the accuracy of 3D visualization registration in evaluating the ablation efficacy.Methods Clinical data about 137 patients with ultrasound-guided ablation for primary liver cancer who admitted to the Department of Interventional Ultrasound of the First Medical Center of Chinese PLA General Hospital from June 2017 to June 2019 were retrospectively analyzed.The 3D visualization registration and 2D enhanced MRI were applied to evaluate the efficacy of tumor ablation pre-and postoperatively,and whether the tumor lesions were completely covered with the ablation lesions or the SAM was reached was analyzed.SAM referred to the area that exceeded 5mm of the primary tumor,which should be inactivated during ablation treatment.The ablation efficacy was divided into the following three grades according to SAM:A_(0):SAM>5 mm,A_(1):5 mm>SAM>0 mm,A_(2):SAM<0 mm,A_(0) and A_(1) represented complete tumor inactivation,and A_(2) represented incomplete tumor inactivation.The 3D reconstruction and nonrigid registration fusion was applied in 3D visualization group,and image side-by-side contrast was applied in the 2D enhanced MRI group.Results Ablation efficacy evaluated by 3D visualization showed A_(0) in 91 cases,A_(1) in 26 cases,A_(2) in 20 cases;and the results evaluated by 2D enhanced MRI showed A_(0) in 109 cases,A_(1) in 17 cases,A_(2) in 11 cases,with significant difference between the two methods(P=0.041).The follow-up results showed that LTP occurred in 22 patients,and these patients were evaluated as 2 cases in A_(1) category and 20 cases in A_(2) category by the 3D visualization;and 11 cases in A_(1) category and 11 cases in A_(2) category by the 2D enhanced MRI(P=0.003).The 3D visualization was superior to 2D enhanced MRI in terms of diagnostic accuracy(98.5%vs 92.0),sensitivity(90.9%vs 50.0%),and negative predictive value(98.3%vs 90.6%)(all P<0.05).Both of the two methods achieved 100%in specificity and positive predictive value.Conclusion 3D visualization technology has high sensitivity for the evaluation of ablation efficacy.Compared with 2D enhanced MRI,3D visualization technology evaluate the tumor ablation efficacy more accurately and quantitatively,and has a higher predictive value for LTP.