Surgeon adjusts a tablet computer to access and visualize planning data during a liver surgery; © Fraunhofer MEVIS /Fabian Bimmer
Until now, surgeons have had to memorize the precise location of important blood vessels in organs and where tumors could likely be found and need to be removed. A new app for tablet computers could support surgeons in the future and help them reduce the rate of complications during operations.
The system, developed by Fraunhofer MEVIS in Bremen, has recently been tested for the first time in Germany. On August 15, the surgical team at the Asklepios Klinik Barmbek in Hamburg successfully tested the app during a liver operation.
A liver cancer operation usually lasts many hours because the organ is difficult to operate. It hosts a branching vessel structure through which one and a half liters of blood flow every minute. If a surgeon makes a cut in an inappropriate place, this puts the patient at risk of severe blood loss. In addition, doctors must ensure that the patient retains enough organ volume for survival and that this volume is sufficiently supplied with blood. To accomplish this, doctors need to know as accurately as possible both before and during an operation where blood vessels inside the organ are located.
The new tablet app promises to deliver this support. It is based on the established MEVIS software for liver operation planning that is employed in clinics worldwide and has been used for more than 6000 patients. Based on 3D x-ray images, the software can reconstruct the locations of blood vessels in the liver for each patient. Before an operation, surgeons can then precisely plan how and where to place the scalpel to most effectively remove a tumor.
However, there are limitations: doctors usually have little opportunity to view the software images during surgery and compare the surgical situation with planning data. Some surgeons even print out images to take into the operating room. “With our app, the entire set of planning data can be shown directly on the operating table” said Alexander Köhn.
At the intervention in Hamburg, the clinicians used a further feature of the new app. With the integrated camera, the tablet could film the liver during the operation. The app then superimposed the planning data – a branched network showing the vessel system in different colors. “Using this function, we can virtually look into the organ and make the tumor and vessel structures visible” said Prof. Karl Oldhafer. This simplifies comparison to determine whether the intervention has gone according to plan. “With this new technology, we are able to better implement computer-supported operation planning for tumor removal” remarked Oldhafer. “The method has great potential. We imagine using it for operations on other organs, such as the pancreas.”
MEDICA.de; Source: Fraunhofer Institute for Medical Image Computing MEVIS