Surgery Simulation Software Promotes Safer Liver Resections

A virtual, three dimensional (3D) reconstructed patient liver helps surgeons rehearse laparoscopic tumor removal before the actual surgery, reducing patient risk.

The Odysseus project, developed by the Institut de Recherche pour les Cancers de l'Appareil Digestif (IRCAD; Strasbourg, France), in collaboration with the Institut National de Recherche en Informatique et Automatique (INRIA; Rocquencourt, France), is developing specialized software for virtual patient modeling (3D-VPM, also known as VR-Anat) to enable the elaboration of patient-specific data for preoperative assessment. Diagnosis and virtual planning (VR Planning) software enable the surgeons to sketch out navigation and tool positioning within 3D images, which can be reconstructed from any multimedia-equipped computer. In planning liver surgery, for example, the software allows 3D imaging of the blood vessels of a patient's liver, helping the surgeon understanding how the liver is segmented. Once trials and validation of the software are complete, their use will enable more accurate diagnosis of secondary liver tumors so they can be removed completely, as well as reduce the size of the liver segments that need to be resected.

Other partners in the Odysseus project have also contributed to the modeling process; France Telecom (Paris, France), for example, has developed a communication system called Argonaute, which allows several practitioners in different locations to interact and advise on the images simultaneously. German endoscope manufacturer Karl Storz (Tuttlingen, Germany) developed the unlimited laparoscopic simulator (ULIS), and SimSurgery (Oslo, Norway) developed the robotic surgery simulator (SEP Robot), both of which add realistic physical properties of texture and tissue resistance to the 3D model of the patient, allowing surgical intervention to be simulated before real surgery.

"Thanks to the 3D modeling,” said Professor Luc Soler, Ph.D., of IRCAD. "The future of liver surgery has gained more precision through accurate definition of the liver's blood vessels.”

Liver surgery has traditionally been based on the anatomy classically described by French anatomist Claude Couinaud, M.D., in 1957; but 3D modeling has shown that up to 50% of patients have a significantly different liver structure from the Couinaud description. Because the success of liver surgery depends on the minimum volume of liver that can safely remain after surgery, accurate knowledge of the topology of the individual liver should significantly increase the number of patients who are eligible for surgery.

Related Links:
Institut de Recherche pour les Cancers de l'Appareil Digestif
Institut National de Recherche en Informatique et Automatique
France Telecom
Karl Storz
SimSurgery