高分辨三维超声和弹性超声对肿瘤边缘侵袭度的精确判断和肿瘤消融的精准导航的研究

Ultrasound-guided tumor ablation is one of the most commonly used image-guided modes. 2D ultrasound has some limitations in clinical application as follows: the difficulty to determine the tumor infiltrating edge and micro tumor thrombus, the lack of accurately guiding measure and monitor equipment based on the tumor boundary; It is difficult to determine quantitatively the ablation safe edge. Therefore, through the basic research to explore the evaluation system which can judge the tumor boundary accurately and micro tumor thrombus, carry out the real-time, feasible and precise tumor ablation plan and evaluate the stereo quantitative safety margin, it is important to improve the effect of local therapy for tumor, and the long-term survival of patients. High resolution 3D CEUS, elastography and Fly-Thru have certain advantages in showing the infiltration boundary of the tumor lesions and micro tumor thrombus, and evaluating the real-time treatment. Therefore, this study intends to through the experiment in vivo and in vitro and using the above new technology to establish the method to evaluate the invasion degree of the tumor boundary and detect the micro tumor thrombus, and on the basis of establishing 3D CEUS pre- and post- treatment by the real-time non-rigid registration in the past, through the basic research about the 3D data acquisition, image segmentation, registration and fusion, to develop the 3D ultrasound virtual planning-evaluation platform. Using this platform to guide, monitor and evaluate the real-time stereo operation, helps to solve the problem of 2D ultrasound diagnosis and treatment at present, to improve the effect of the ablation, which is important for promoting the development of ultrasound-guided minimally invasive tumor therapy in China.

超声引导肿瘤消融是一种最为常用的引导方式。但二维超声存在：肿瘤浸润边界和微癌栓难以准确判断；缺乏依据肿瘤边界制定的精确引导措施和监控设备；消融的安全边缘未能精确定量测量等局限。因此，通过基础研究探索可精确判断肿瘤边界和微癌栓、实时精准肿瘤消融计划及可立体量化安全边缘的评估系统，对提高肿瘤局部治疗疗效及病人长期生存率具有重要意义。高分辨三维超声造影及弹性成像、Fly-Thru对显示肿瘤病灶边界浸润和微癌栓情况及评估实时观测治疗有一定优势。因此，本研究拟通过体内、外实验利用以上新技术确立评估肿瘤边界侵袭度和检测微癌栓的方法，并在已建立三维超声造影术前术后的实时非刚体配准基础上，通过三维数据采集，图像分割配准及融合等基础研究，研发三维超声虚拟规划-评估平台，并利用该平台进行实时立体手术引导、监测及评估，以解决目前二维超声诊疗的不足，提高消融治疗疗效，对推进我国超声引导下肿瘤微创治疗具有重要意义。

超声引导下肿瘤消融是一种常用的治疗手段。但二维超声上存在：肿瘤浸润边界和微癌栓难以准确判断；缺乏依据肿瘤边界制定的精确引导措施和监控设备；消融的安全边界未能精确测量等局限，从而导致肿瘤消融后局部复发率高。为解决二维超声诊疗的不足，提高肿瘤消融的局部疗效，本研究通过体内、外实验探索高分辨三维超声和弹性超声对肿瘤边缘微侵袭度的精确判断和微癌栓的检测，并在已建立三维超声造影术前术后的实时非刚体配准基础上，通过三维数据采集，图像分割配准及融合等基础研究，研发三维超声虚拟规划-评估平台，并利用该平台进行实时立体手术规划、引导、监测及评估。结果表明超声造影和弹性成像可发现比二维超声更客观的微浸润的影像特征，准确率约60%-70%，而人工智能多模态影像组学分析可使超声对微浸润的判断准确性达到约90%的新水平。开发了针对术前术后不同灌注三维超声造影的配准算法，克服造影剂进入组织时间不一致，实现三维超声造影图像容积数据之间快速、精准、自动配准，精度误差＜2mm，速度＜4s。通过设计体外正交实验，探讨影响单模态三维超声造影图像配准成功率的因素，结果表明血管内径是配准成功率的独立影响因素；当血管内径<2mm时，自动/交互式配准成功率明显降低。应用自动/半自动配准技术，多平面比较病灶与消融灶的空间立体结构，可精确计算出肿瘤消融的安全边界，实现对肝癌消融疗效的快速评估，并与公认的EDDA系统进行比较，对系统的准确性进行验证；结果表明快速配准成功率约90%，三维超声造影即时评估平台和CT融合成像方法评估安全边界有高度的一致性，Kappa值为0.897，并可指导补充消融，以预防肿瘤局部进展的发生。目前，单模态三维超声造影虚拟规划-实时引导-即时评估系统已经实现产品转化，已经整合到迈瑞“北辰”机器上，已在多家单位进行相关临床研究和应用，实现集肝癌消融术前规划、术中引导及术后评估于一体，“一站式”地帮助临床实现精准消融。