The Design And Implementation Of Virtual Nonanatomical Hepatectomy

Liver cancer is the one of the diseases having high mortality rates. Currently,the preferred method for the treatment of liver cancer is hepatectomy. Surgery plandesigning, path planning and plan evaluation before surgery are important toimprove the efficacy of hepatectomy. We designed and simulated the liver virtualresection in computer-aided liver surgery planning, so that doctors can plan cuttingpath, choose reasonable surgery plan to improve the effect of treatment of livercancer to satisfy the requirements of nonanatomical hepatectomy.According to different cases and different needs, we designed and implementedthree functions: virtual plane resection, virtual multiple plane resection and virtualcurve resection. Through observing the three-dimensional liver, tumor and bloodvessel model, the user select cutting mode and determine the cutting planes. Virtualresection can be ultimately completed by translating and rotating the cutting planes,also deformation operation, then the user can analyze and evaluate the surgery plan.We used principal component analysis algorithm and needling picking algorithm todetermine the cutting planes. Then cutting planes were modified through geometrictransformation and Bezier surfaces. And we used three-dimensional region growingalgorithm and bilinear interpolation algorithm to mark volume data.The study aimed to provide a computer-aided treatment means for the surgicaltreatment of liver cancer. Through cooperation and communication with theradiologists, the design took the actual needs of users into account, and virtualcutting process simulated liver cancer surgery vividly. And the interaction process issimple, to ensure users completing the surgery planning in a short time efficiently.Finally, we used clinical CT data to validate and evaluate the system. We couldsee the process was fast and convenient, updating of models drawn was time saving, hepatectomy was well simulated, and cutting surfaces were smooth. Doctorsanalyzed and evaluated the surgery plan easily. Compared to preoperative3D modelinformation and virtual resection process and the actual surgery process, informationprovided by the system was consistent with the actual situation. The virtual cuttingprocess played a very helpful role in the doctor’s surgery planning.