Looking for the best size of instrumentation for vitrectomy

"With 23-gauge you can do everything that you do with 20-gauge. There is no limitation at all," said Dr. Tornambe, who is in private practice with Retina Consultants San Diego.

Most clinicians prefer 20- or 25-gauge or switch back and forth depending on the procedure. Dr. Tornambe advocates 23-gauge as a replacement for 20-gauge and a possible alternative for 25-gauge instruments. "I'm not saying that 23 is going to replace 25. I would think that 23 should replace 20," he said.

"That was the size that they could do with their engineering capability at the time in the '70s."

No studies were conducted to determine the best size for vitrectomy instruments, he explained. It was more a matter of the technologic limits of the era. As technology has improved, most manufacturers jumped to 25-gauge tool systems rather than 23 gauge.

Favor small instruments While he endorsed the trend toward smaller instruments, Dr. Tornambe did not become an enthusiastic convert to 25-gauge technology because of flaws in the first generation of instruments, including problems with trocars that caused retinal tears and the extreme flexibility of the tools. These flaws have largely been overcome with newer instruments, but Dr. Tornambe has not warmed to 25 gauge and sees a niche for 23-gauge tools as a way to take advantage of the best aspects of both the larger and smaller instruments.

"What we are looking for is outcomes," Dr. Tornambe said. "Down the line, my patients can see as well as patients who have undergone a 25-gauge procedure , if not better, because we do a more complete vitrectomy."

Self-sealing capability Points in favor of 23 gauge include the self-sealing capability of a nonmanipulated 23-gauge wound, according to Dr. Tornambe. A wound created to insert a 23-gauge infusion cannula, for example, does not have to be sewn up after the cannula has been removed.