A new computer-guided system that combines virtual reality technology with the skills of a surgeon's hands is allowing safer surgery and shorter recovery times for neurosurgical patients.

Developed by the German company BrainLAB, the VectorVision computer system maps a patient's brain and displays it as a three-dimensional image on a computer screen. The surgeon operates while viewing the image on the screen, which serves as a visual guide.According to Dr. Eugenio Vargas, a neurosurgeon at Methodist Medical Center, of Oak Ridge, Tenn., the system gives surgeons added precision by allowing them to view the exact position of their scalpels and other instruments in relation to the inside of a patient's brain.

"It's much like using a road map to find the quickest, most direct route to where you're going," said Vargas.

Methodist Medical Center acquired the system in March and has so far used it with four patients.

While the ability to visualize intracranial structures non-invasively has been revolutionized by advancements in diagnostic imaging, until VectorVision, three-dimensional images were unavailable to the surgeon.

That meant the surgeon had to mentally apply the diagnostic images to the three-dimensional patient anatomy.

VectorVision uses two cameras that constantly track small reflective spheres attached to surgical instruments. The images are relayed to a computer screen programmed to display three-dimensional images of the brain and instruments.

The computer also allows physicians to see exactly where the tumor or malformation is in relation to the instruments. In addition, the physician can work through smaller incisions. And the system is wireless, freeing the physician to focus on the patient and procedure rather than technology.

"Because the system allows you to rehearse with a virtual tip prior to cutting, you can plan the best point of entry and best angle," said Vargas.

"Armed with this information, you can avoid damage to other areas of the brain."

Prior to surgery, five adhesive markers are attached to the patient's scalp near where the surgery will be performed. In the past, a frame that looks much like a drum would have been attached to the patient's head with a series of screws.

The markers allow registration on the computer software. Before using the image-guided surgery system, the physician simply touches his probe to each marker to complete full registration. This reduces overall patient registration time to a few seconds instead of 15 minutes.

Patient data obtained from CT, MR and other imaging technology is fed to the computer system along with the physician's strategic plan for the optimal surgical approach..

This information is then used to create the three-dimensional image of the patient's anatomy and the tumor or other malformation. It's the information the physician uses to calculate distances within the brain and how big a lesion is.

With the image displayed on the computer screen, the surgeon makes a small incision at the point of entry and performs the surgery while watching the screen.

"Where before I had to make a larger incision, now I know the exact point of entry and can go in through a much smaller incision with a higher degree of safety to remove the lesion," said Vargas. "Translated, that means more accuracy, finer detail and time savings."