胆总管结石患者的可视化仿真手术研究

目的 研究胆总管结石患者CT扫描数据的图像分割、三维重建和胆总管切开取石与T管引流术的可视化仿真手术.方法 采用64排螺旋CT扫描收集患者的数据;运用医学图像处理系统(MIPS)对患者的CT数据进行自动分割和三维重建,得到肝胆的三维模型,然后在FreeForm Modeling System(FreeForm)对模型进行加工;利用系统的GHOST SDK的软件进行虚拟手术器械的二次开发并实施胆总管结石的可视化仿真手术.结果 共采集平扫、动脉期、门静脉期、肝静脉期的数据,并由DICOM转换成BMP格式;MIPS分别对各期数据进行自动分割和三维重建,得到含胆总管结石的肝胆三维模型,并以STL格式输出;三维模型导人FreeForm进行平滑加工,不同的组织结构以不同的颜色渲染,三维模型更有立体感,形态逼真,将自行开发的手术器械T管等导入系统,利用力反馈设备PHANToM操纵下可以完成胆总管结石的可视化仿真手术.结论 MIPS可以有效、快速地完成胆总管结石的CT图像自动分割、三维重建.在FreeForm进行二次手术器械的开发后,利用力反馈设备PHANToM操纵下可以模拟胆总管结石的仿真手术.

Virtual surgery for choledocholithiasis

Objective To study the image segmentation, three-dimensional (3D) reconstruction and simulation operation of choledocholithotomy and T-tube drainage based on the computed tomagraphy (CT) data of patient with choledocholithiasis. Methods Patient with choledocholithiasis underwent 64-slice spiral CT imaging. The images segmentation and 3D reconstruction were performed by Medical Image Process System (MIPS) to construct the 3D model of the hepatobiliary system. The model was modified by FreeForm Modeling System. The virtual surgical instruments were developed by GHOST SDK software, and were imported to the virtual surgery. Results The data of plain, arterial phase, venous phase and portal venous phase scanning were collected, and the data stored in DICOM format were transformed to BMP format. A model of the hepatobiliary system was constructed after the data was segmented by MIPS, and then the model was exported in the STL format. The data in STL format were imported to FreeForm Modeling System for smoothing the model. Different structures were assigned different colors to make the model more vivid. The self-developed virtual surgical instruments were imported to the system, and the virtual surgery for choledocholithiasis was performed with PHANToM. Conclusions With the help of MIPS, the image segmentation and 3D reconstruction of the model are finished rapidly and effectively. After the virtual surgical instruments are developed in FreeForm Modeling System, the virtual surgery can be achieved in the 3D model with the assistance of PHANToM.