Surgeons can swab a patient’s exposed liver lightly on the surface with a special stylus, capturing the shape of the organ during surgery, and a computer can match that image with the CT scan on a screen. This GPS-like ability is far better than guessing where the tumor and vessels are by feeling for them, but even this road map can be off by centimeters and leaves surgeons guessing.

New software simulates the forces being applied during surgery.
(Credit: John Russell/Vanderbilt)

Researchers have developed a new surgery-tested software that better marries the CT scan’s image with the tracked tool’s. It’s an advance that stands to help more than a half-million liver cancer patients worldwide each year.

The trick to fixing that error without investing in additional expensive equipment is software that makes a computer model out of the original image of the liver and simulates the forces being applied during surgery — such as packed gauze lifting the liver upward. The computer adjusts the CT-derived GPS map to better match the exposed organ shape in the OR.