Second sight for surgeons

A new computer guidance system called the navigator gives neurosurgeons and orthopedic surgeons a cutting edge at Kalispell Regional Medical Center.

Neurosurgeon Dr. Rob Hollis summed up the importance of the high-tech equipment to his patients.

"As you can imagine, in brain surgery, accuracy counts," he said with a smile. "What it's all about is preserving function."

Orthopedic surgeon Dr. Larry Iwersen said the computer-guided system helps surgeons position knee replacements in patients with anatomies outside the normal range.

"If you get the perfect fit, it will last longer," Iwersen said.

He said the system also enhances minimally invasive knee procedures. The navigator displays where the surgeon cannot see inside the small incision.

Hollis' new partner, neurosurgeon Dr. Douglas Griffith, described the experience of computer visualization for neurosurgeons.

"There is no skull," he said.

Griffith operated with computer guidance for the past decade at his previous practice in Virginia.

He marvels at the advances made since his residency days when neurosurgery was "exploratory," often involving multiple incursions through the skull to find a tumor.

"It was like woodpecker surgery," he said. "It was awful."

For the past several years, Hollis and Iwersen and other surgeons at Flathead Valley Orthopedic Center trained then tested several different computer guidance systems. They chose the Stryker Navigation System, which required more than a $250,000 investment by the medical center.

It works by combining computers, infrared cameras and wireless instruments to produce detailed, three-dimensional computer images. As the surgeon works, the high-tech network tracks in real time the placement of instruments inside the patient.

Karen Lee, operating room manager, said it was amazing for a hospital the size of Kalispell Regional Medical Center to have this technology.

"A lot of this is a tribute to the quality of physicians that we have here," she said.

Because of the testing period, Lee said the medical center was able to time the purchase to acquire the latest upgrade Stryker offered. According to Hollis, the advance of computer technology has made a world of difference in guidance products.

"We were one of the testing sites in 1994-1995," he said. "Back then, it was just miserable - It was slow and it broke down a lot."

Hollis described the streamlined process with the Stryker Navigation System.

After a diagnosis of a problem such as a brain tumor, the patient has an MRI or CT scan with little buttons on the head which act as alignment markers. The information from the scan feeds into the computer.

"This equipment uses the same technology as GIS tracking," Hollis said.

The software provides a definitive rendering in three-dimensional space. As the neurosurgeon touches a pointer to any place on the patient's skull, the equipment lights up that precise area on the screen.

"I had a 14-year-old child that had a brain tumor right on the base of the temporal lobe," Hollis said.

Although the tumor was not cancerous, it was causing the child to have seizures. Hollis used the navigator equipment to pinpoint the precise area to penetrate the skull to remove the tumor.

Hollis said the child was back in school within a week.

He also used the navigator to operate on a 15-year-old cheerleader with a tumor close to areas involved in her vision. Without the navigator, Hollis said he would never have attempted to remove the tumor.

"Thanks to the equipment, I was able to remove it without injuring the optical field," he said.

Iwersen recently used the navigator to replace a knee on a patient with a thigh bone bowed by an earlier fracture. He said these unique patients benefit the most from the navigator.

The surgeon held up the two diamond-shaped trackers he installed above and below the knee on the patient. Iwersen then used the pointer to trace around the joint.

"We map the anatomy of the patient," he said.

The navigator's software collated the information from the pointer to display a three-dimensional picture of the patient's unique knee.

The computer also figured the angles, lines and measurements needed to best align the prosthetic knee.

As Iwersen operated, the monitor showed his progress as he removed bone and installed the new knee.

"This gives us all we need to be assured of making precise cuts," Iwersen said. "We're the only site in Montana that has this" for orthopedic surgery.

In about two months, he said, the hospital would have additional equipment to use the navigator for hip replacement surgery.

The system offers the same benefits for hips as knees by displaying the individual patient's biomechanics prior and during surgery.

For orthopedic patients, the navigator may mean a shorter hospitalization, fewer complications and improved joint stability. Neurosurgical patients have the peace of mind of knowing the equipment may reduce mortality, paralysis or loss of function.

Hollis, Griffith and Iwersen agree the navigator's benefits justified Kalispell Regional's investment. But technology means little without a skilled surgeon.

"This is our compass," Hollis said. "But it doesn't absolve us from driving the ship."

Reporter Candace Chase may be reached at 758-4436 or by e-mail at cchase@dailyinterlake.com