Non-invasive, effective liver surgery with a new technique

Operating on cancerous tumours of the liver is difficult for a number of reasons. The liver is an organ with many blood vessels, and liver tumours are usually embedded in the tissue.

“The challenge is to locate the tumour and remove it with the right margins to save as much of the liver tissue as possible, which the patient needs to keep,” says Mårten Falkenberg, a surgeon at Sahlgrenska University Hospital, who helped develop the new technique.

Increased need for guidance

There are currently two established methods for liver surgery. One is open surgery, in which the abdominal cavity is opened so that the surgeon can look into the abdomen and feel the location of the tumour with their fingers to some extent. The other method is keyhole surgery. A camera is inserted through a hole in the abdominal wall, the surgeon’s instrument through another, and the surgeon works with the help of camera images on a screen.

“We actually prefer keyhole surgery because it’s less invasive for the patient, but the ability to feel the tumour with your fingers disappears, which increases the need for guidance to show you where it is,” says Mårten Falkenberg.

Navigating by camera images alone is difficult. The liver is a homogeneous organ. It simply looks almost the same from different angles. This is where the new technique comes in. A 3D scan of the liver is already standard before surgery. The idea was developed by researchers including Torbjörn Lundh and Klas Modin at the Department of Mathematical Sciences at Chalmers University of Technology and is based on enhancing the images that are taken.

“We use augmented reality, based on the pre-operative scan and newly developed algorithms, to produce an image of what the tumour looks like and where it is located. This image is superimposed on the camera image that the surgeons see during the operation, as a guide for how to cut to get the tumour out,” says Klas Modin.

Making use of existing information

The particular feature of this technology is that it is based on existing information and technical equipment. Images based on the pre-operative scan are displayed in real time as a layer on top of the camera images during the operation. After having attended a liver operation at Sahlgrenska University Hospital, Klas Modin and Torbjörn Lundh applied this experience when they worked on their proposal. One thing that made a strong impression was that there is already a great deal of technical equipment in the operating theatre, and large amounts of information are constantly being shared.

“Based on how operations are currently performed, with the aim of being minimally invasive, i.e. keyhole surgery, we want to contribute a solution that is also minimally invasive in terms of the surgeons’ working environment,” says Torbjörn Lundh.

More about the research

The research behind the method began in 2016. In 2021, the company Navari Surgical was founded in collaboration with the business incubator Chalmers Ventures. The aim of the company is to further develop the technique and make it available on the market so that it can be used in healthcare.