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An encore for Gary Onik
The father of US-guided tumor ablation turns to telementoring

By C.P. Kaiser

In 1982, Dr. Gary M. Onik, then a second-year radiology resident at the University of California, San Francisco, was performing a CT-guided liver tumor biopsy when an idea changed the direction of his medical career--and medicine itself. If a needle for biopsy could be guided deep within a patient's body by cross-sectional imaging, then a destructive agent might also be guided directly into the tumor in the same manner.

Working with Boris Rubinsky, a biomedical engineer at the University of California, Berkeley, Onik designed an ultrasound-guided system that for the first time enabled cryosurgeons to see what they were doing. To this day, Onik corresponds with one of his first cryosurgery patients, who at the time had seven metastatic liver lesions and was deemed terminal. She was 34 then, with a newborn infant.

"One the great joys of my career has been to watch her and her family grow for the last 16 years," he said.

After nearly two decades of refining his percutaneous ablative therapies, Onik wants to teach them through robotic telementoring. Robotics and percutaneous procedures are a good mix because there's no cutting and sewing: just guide an instrument to the site and freeze.

"From a robotics point of view, that's pretty simplistic," he said.

Celebration Health/Florida Hospital, where Onik is director of surgical imaging at the Center for Surgical Advancement, has just opened a high-tech surgical learning center. When Onik gets finished with his project, he'll be able to robotically control students' instruments, whether they're in Orlando or Odessa.

Friends and colleagues are not shy about calling Onik a genius. He dismisses the label and says he merely sees things that are obvious. Not so, said Dr. Fred Lee Jr., chief of abdominal radiology at the University of Wisconsin.

"His thinking is not limited by specialty or modality," he said. "His liver tumor ablation technique was pure genius, a radiology solution applied to a surgery problem using an engineering device."

Onik is still rolling out new techniques and instruments. Last year, he introduced a safety procedure for percutaneous prostate cryosurgery that involved injecting fluid into Denonvilliers' fascia to artificially increase the space between the prostate and the rectum. Later this year, he'll publish a study of a potency-sparing technique that preserved sexual functionality in 80% of prostate cancer patients. Then he'll swing up to Wisconsin where he and Lee will test a patent-pending device: a combination radio-frequency/cryoprobe that takes advantage of each ablative procedure's strengths. The government gave its blessing to Onik twice in the last year--it approved Medicare payments for cryosurgery, first as a primary treatment for prostate cancer, then for patients without curative options.

At home, where there are two dogs, two teenagers, and two pre-med progeny, Onik insists he's all thumbs.

"My wife thinks I'm useless and have always been that way," he said. "As a kid, my erector set got put in the corner and stayed there."

But sitting in his garage is what Onik describes as "a revolutionary safety instrument" that recognizes when it's about to puncture a vessel. It sends out a pulse of light, looks at the spectra coming back, and teaches itself over time what a particular structure looks like. Developed with Boris Rubinsky and David Otten, a Rubinsky protégé, it can be trained to recognize veins, arteries, nerves, bile ducts, whatever.

Talk with Onik long enough and he'll slip into the subject of sailing. Not one to sit quietly, he's making his presence felt dockside. He's lobbying boat companies to adopt a high-tech refrigeration system initially designed for NASA, and he thinks the electric engine of the Mars rover has good potential for propelling boats.

As for his healthcare initiatives, he has two major projects pending. One is cryoliposuction.

The other project is a percutaneous anterior lumbar diskectomy procedure, for which he invented a grasping forceps that pushes all but the disk material out of the jaws of the grasper. The instrumentation and animal studies have been ready for five years, but he's been waiting for a sophisticated intraoperative CT scanner with an integrated guidance system. Now that such systems are available, he's lobbying manufacturers to install one in his OR.

The anterior diskectomy project brings Onik full circle and back to an early idea: image-guided posterior lumbar diskectomy, which he proposed as a first-year resident at UCSF. Onik's advisor at the time was Dr. Clyde Helms, now chief of the musculoskeletal section in the radiology department at Duke University.

"Nothing like that had been done before," Helms said. "I thought he was crazy until I read his proposal. He had everything thoroughly worked out."

It took Onik two years to develop the tiny instrumentation. Then he had to find a patient willing to take the risk.

"Gary's very persuasive," Helms said. "He explained to the man that it might not help, but it probably wouldn't hurt."

The instant the procedure was finished, the man got off the table and gave Onik a big hug, according to Helms. The pain he had felt for years was suddenly and dramatically gone.

It was a great pro- cedure for 1981, Onik said, but very limited. The anterior diskecto-my can provide solutions for those limitations.

"Now we could remove extruded fragments on Monday and that man could play the Super Bowl on Sunday," Onik said.

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Michael E. Phelps, Ph.D.
Dr. David Channin
Dr. Gary M. Onik
Dr. Geoff Rubin


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