Prostate Innovation Helps Avoid Impotence New Machine Warns Surgeon About Danger To Vital Nerves

Prostate surgeons are about to get a new machine to help them avoid slicing vital nerves during cancer surgery - cuts that can leave their patients impotent.

UroMed Corp.’s new CaverMap, unveiled Thursday, is similar to a metal detector: The closer the surgeon’s knife gets to a nerve, the faster the machine beeps in warning.

Some urologists welcomed the machine, saying even today’s popular nerve-sparing prostate cancer surgery still leaves too many men impotent because doctors have no precise map of the microscopic nerves.

“Their anatomic location - it’s a guesstimate,” said Dr. Dan Watson, a Charlotte, N.C., urologist who helped in the machine’s early development at Harvard University.

But just how big a help the CaverMap will be remains to be seen, cautioned doctors from the Food and Drug Administration and the American Urological Association.

UroMed reported that in one study, 92 percent of prostate cancer patients had sexual function a year after surgery, a jump from the 30 percent potency rate the same surgeon achieved before he tested the CaverMap.

But while the FDA approved CaverMap as an aid in detecting key nerves, medical officer Dan Schultz warned that only 14 men stayed in UroMed’s study for the full year. That is entirely too little data to predict whether good surgeons will notice much change if they buy the machine when it goes on sale next year, he said.

“It’s not a replacement for a surgeon who knows how to do this operation,” Schultz said.

Still, “It’s certainly worth trying,” said Dr. Michael Manyak, George Washington University’s urology chairman and head of technology assessment for the AUA.

“One thing you’d like to eliminate is the component that you’re accidentally or inadvertently dividing nerve tissue,” said Manyak, who called the preliminary study encouraging. “I see no downside to using this.”

CaverMap is based on nerve stimulation technology already widely used in delicate facial surgeries.

An electronic sensor is wrapped around the penis. The surgeon holds the nerve stimulator in a small probe. When the surgeon stimulates a nerve, the sensor within 15 seconds can detect a reaction that is too small for the surgeon to see, said UroMed Chief Executive John Simon.

If the surgeon probes a nerve, the machine beeps in warning. “You know exactly which electrode the nerve is under, so you know where to do the cut,” Simon explained.

Dr. Patrick Walsh, urology chief at Johns Hopkins University, pioneered nerve-sparing prostate surgery and reports some of the nation’s best results. Walsh says age is a key: Ninety percent of his 40-something patients recover sexual function vs. 60 percent of men in their 60s and 25 percent of those in their 70s.

Walsh is preparing to perform his own, large study of the CaverMap early next year.

Impotence rates “vary widely from doctor to doctor,” Walsh said. “Having done over 2,000 (operations), I have a sixth sense about where things are. That takes a lot of experience. The question is whether this machine will shorten the learning curve for someone without” that experience.