Minimally Invasive Computer Assisted Surgery

Minimally invasive laparoscopic interventions have the potential to reduce the trauma caused by liver surgery. Preoperative planning data (CT/MR images) is used to precisely localize the tumor and to plan the resection. During the operation, real time intra-operative ultrasound images are taken and the surgical field is visible through the laparoscope. However, estimating the position of the tumor in deformable organs is challenging, particularly as haptic feedback is missing. Therefore, a computer system to assist the intervention and map the pre-operative planning data onto the actual liver offers a true benefit for the surgeon.

In an ongoing project, such an assistance system has been developed. Based on electromagnetic tracking of ultrasound, instruments, and laparoscope, the LapAssist system visualizes the actual situation with respect to the planning data. The position and deformation of the liver are estimated and the surgeon is guided to resect the tumor as planned. Currently, the research is focused on solving the problem caused by organ deformation which induces wrong intraoperative localization of the tumor.