Does Size Really Matter?
By: Paul S. Koch, M.D.

I remember watching my family's tiny black and white television while George DeWitt coaxed contestants to "Name That Tune!" "I can name that tune in seven notes," one would say. "I can name that tune in six notes," the other would challenge, and so back and forth until the minimum dare was reached, usually three or four notes, occasionally only one.

I feel like I'm still watching that old show again and again whenever I go to a convention. "I can inject that lens through a 2.8-mm incision," one surgeon says. "I can inject it through a 2.6-mm incision," another responds, and so on until the boasts become silly.

There is one indisputable physical fact about injecting IOLs: the tip of the cartridge is a specific size fits that through a specific hole. If you try to shove it through a smaller hole it won't fit. It'll get through only if you rip the hole wider to accommodate it. That violates all kinds of rules for surgery, which encourage the use of scalpels rather than claws to make openings in the body.

If you prefer to force the injector through an unsuitably tight incision, it should not surprise anyone that the ragged incision does not close nicely and fluid leaks out. Stromal hydration helps, but only for a few minutes, then the incision leaks again. Leaking goes both ways. Fluid can leak out; surface stuff can leak in.

It is, then, understandable that recent studies have associated corneal incisions with a higher risk of endophthalmitis. In the old days, operating through the sclera, we knew we had a tight incision, either by examination or by sewing it tight. In modern times we often ignore a leakable corneal incision lest, heaven forbid, we actually have to use a suture in our "sutureless" cases.

I haven't had a leaking incision needing a suture or stromal hydration for more than a year. That's when I decided to go wide. Before injecting my lenses, I use a blunt keratome to enlarge my incision, in every case, to 3.5 mm. The edges are never torn, so the incisions close nicely and don't leak.

Wound Integrity is Key

Laugh at me if you want. Maybe my incision is a little wider than yours, or maybe a little wider than you think yours is. I do know this: my incisions close up tightly right away because I stopped playing the size game and got serious about making — and preserving — an excellent incision.