Cataract surgeons can reduce the rate of complication from intraoperative floppy iris syndrome (IFIS) by using certain techniques before and during surgery.
San Diego-Cataract surgeons can reduce the rate of complication from intraoperative floppy iris syndrome (IFIS) by using certain techniques before and during surgery, according to I. Howard Fine, MD, who spoke here at the annual meeting of the American Society of Cataract and Refractive Surgery.
With soft to moderately firm cataracts, Dr. Fine said, his technique of choice is bimanual microincision phacoemulsification because the approach uses small incisions-approximately 1.1 mm wide at the entrance to the anterior chamber-and, therefore, iris that prolapses remains in the eye, trapped in the incision.
The instruments are placed equidistant from the posterior capsule and the corneal endothelium, Dr. Fine said. Minimal phaco energy is required; the cataract is removed almost exclusively with fluidics.
After removing the endonucleus, he said, the epinucleus is positioned above the iris and keeps it in place. "The position of the irrigator keeps fluid above the iris as well and tends to discourage fluctuations and floppiness of the iris," Dr. Fine added.
He said he then removes the epinucleus in the usual manner. "Once again, the anteriorly placed irrigation tamponades the iris and prevents billowing," Dr. Fine said.
When the nucleus is harder, Dr. Fine said, he uses viscoelastic (Healon 5, Advanced Medical Optics) to dilate the pupil. He emphasized the need for a slightly larger capsulorhexis than in other techniques, to remove nuclear material out of the capsular bag.
"We do one endolenticular horizontal chop, and after that chop, we keep the irrigating chopper high in the anterior chamber throughout the remainder of the phaco procedure, mobilizing nuclear material from the endolenticular space and bringing it up to the chopper for further disassembly," he said. "We try to keep the phaco tip occluded as much as possible, and if there is a clearance of occlusion, we try to go directly to foot position one rather than two to avoid evacuating [viscoelastic] from the eye."
Keeping the irrigating chopper high in the anterior chamber allows the fluid to press against the iris and keep it retroplaced, preventing billowing or floppiness of the iris and helping to maintain pupillary dilation, Dr. Fine said.
He said he uses a bevel-down phaco tip to ease mobilization of the nuclear material from the endolenticular space. Then, he evacuates the epinucleus in the usual manner.
"Throughout the procedure, we do lose some [viscoelastic], and as a result, the pupil will come down some, but the iris will never be allowed to billow or become floppy," Dr. Fine said.
After he completes phaco, he uses viscoelastic again to dilate the pupil.
Next, to avoid mobilizing the viscoelastic, he moves the aspirator in a circumferential pattern around the capsulorhexis to evacuate cortical material from the capsular fornices.