Coaxial/Microphaco Technique

When it comes to the surgical techniques, the differences between standard coax­ial phaco and coaxial microphaco are few and relatively subtle. Those of note include:

I0L implantation. Robert Osher, MD has developed the following steps for IOL implantation:

1. Load the IOL into the cartridge as shown in the photo (previous page),
   so the haptics open like a book.
2. Firm up the eye and apply countertraction. To do this, he puts a second
   instrument in the stab incision.
3. Inject the IOL bevel down within the incision.
4. Inject the lens quickly so it does not get stuck in the incision.
5. Do not use a typical two-handed injector. Instead, use a one-handed, plunger-style RUMEX injector 16-2803 or 16-2804.

Bottle height. The sleeve used in coaxial slightly restricts fluid flow into the inci­sion, but raising the bottle height increas­es the flow pressure. "This is an impor­tant point," Robert Osher, MD said. "I conducted an experiment comparing all of the dif­ferent choppers, with the bottle at 100 centimeters. With bimanual micropha­co, I got 20 cc to 60 cc per minute [depending on the chopper]. With coaxi­al microphaco, I got about 85 cc per minute—slightly less than regular phaco but a big improvement over bimanual. As a result, I raise the bottle around 25 percent, just to play it safe. It gives me a completely stable chamber."

Choice of instrument. "Presently, there is not a great steel blade that creates a consistent 2.2-mm incision," Dr. Masket said. "From my own experience, I know that there is a risk of stretching the tis­sue if the incision is smaller than 2.2 mm. But I do have a diamond blade (6-20/6-107) that works perfectly and does provide a genuine and consistent 2.2-mm inci­sion." He added that "the standard capsulorhexis forceps may not work— instead, one may use those forceps made for bimanual microphaco (4-0371)."