surgical pearls
Managing Floppy Iris Syndrome
Use of Flomax has been tied to this complication.
By Jerry Helzner, Senior Editor

David F. Chang, M.D., and John R. Campbell, M.D., have recently identified a new small-pupil syndrome they've named Intraoperative Floppy Iris Syndrome (IFIS). They've tied it to use of Flomax, the most commonly prescribed alpha-adrenergic blocker for the treatment of benign prostatic hypertrophy (BPH).

IFIS during cataract surgery is characterized by: iris billowing in response to normal irrigating fluid currents; a strong tendency toward iris prolapse; and progressive miosis during the phaco and cortical irrigation/aspiration (I/A) steps.

In this article, we'll provide several pearls that surgeons should consider when confronted with a potential IFIS case.

IFIS is characterized by iris billowing, prolapse to phaco and side port incisions, and progressive miosis during phaco.

Mitigating IFIS

Dr. Chang offers the following surgical pearls for preventing or mitigating IFIS:

"If the pupil dilates poorly preoperatively, you should specifically ask about prior Flomax use. Even if it has been stopped for 1 to 2 years, IFIS can still occur, indicating that there must be some permanent change to the iris dilator muscle. Some urologists prescribe Flomax for urinary retention symptoms in women, and predictably, IFIS has been encountered in female Flomax patients.

"It is not clear whether other nonsubtype-specific alpha-1 blockers cause IFIS. While the IFIS patients in our two studies were all on Flomax, a few anecdotal reports note IFIS in patients on Hytrin, Cardura, and Uroxatrol.

"Several features of IFIS increase the risk of complications for an unsuspecting and uninformed surgeon. First, if the pupil is small, commonly used mechanical stretching techniques, with or without partial thickness sphincterotomies, are ineffective in maintaining an adequate pupil diameter. Furthermore, some IFIS pupils dilate quite well, or expand well enough following viscoelastic injection to make the capsulorhexis step quite straightforward. It is not until hydrodissection and phaco that the problems of IFIS suddenly and unexpectedly occur.

"We reported increased retrospective posterior capsule rupture rates with IFIS, and believe that the unanticipated cascade of iris misbehavior was the likely explanation.

"A number of different approaches have been tried with varying success. Stopping the Flomax for 1 to 2 weeks seems to permit wider dilation in some eyes, but doesn't alone prevent IFIS.

"Dr. Sam Masket feels that stronger cycloplegia, such as with atropine, may help. Dr. Dick Lindstrom feels that supracapsular phaco is a helpful technique, wherein the prolapsed and tilted nucleus keeps the pupil from constricting all the way down. Drs. Bob Osher and Doug Koch rely on Healon5 (see below). "I have found that the tighter 1.2-mm incisions of bimanual microincisional phaco are of some help in preventing iris prolapse.

"I believe that all of these strategies work much better if the iris dilates reasonably well to begin with, and are less effective if the pupil is already small. In that case, the best strategy is to employ iris retractors in a diamond configuration as described by Dr. Tom Oetting. Although this increases the cost and surgical time, it assures a safe-sized pupil opening throughout the case. Pupil expansion rings are another option, but can be more difficult to insert if the chamber is shallow, or the pupil is small."

Using Healon5

To safely and effectively manage the challenges of IFIS, Robert H. Osher, M.D., uses his slow-motion phaco technique and Healon5.

In slow-motion phaco, vacuum, aspiration and infusion are carefully managed. After an initial vacuum of 250 mmHg to burrow into the lens, vacuum and aspiration rates are kept lower than normal, which allows a lower infusion rate and fosters stability.

The viscosity and space occupation properties of Healon5 make it ideal for use with this technique, Dr. Osher says.

"First, viscomydriasis with Healon5 allows me to create an adequate capsulorhexis without iris prolapsing to the wound," he explains.

"During nucleus chopping and removal, not only does the slow-motion phaco preserve the Healon5 in the anterior chamber, it deters the floppy iris from 'leaping' into the phaco tip, even though the pupil may get smaller. I have also learned how to remove cortex without disturbing the OVD, still keeping the floppy iris from leaping."

Disposable iris retractors placed in a diamond configuration in IFIS patient. Subincisional retractor is placed through a separate stab incision just posterior to the phaco incision.

For removal of the Healon5, Dr. Osher places the I/A tip under the IOL, directs the port toward the single-piece acrylic IOL, and with several seconds of high vacuum, evacuates the viscoelastic from the capsular bag. To complete the evacuation, he places the tip in the anterior chamber with the port toward the cornea.

Before he removes the irrigating tip, he puts the 27-gauge cannula through the stab incision and holds it against the optic. He injects Miochol as the I/A tip is being withdrawn.

"This maneuver keeps the chamber from abruptly shallowing because the Healon5 effectively masks positive pressure," Dr. Osher says. "The iris prolapse is retarded by the deeper chamber into which the pupil rapidly constricts from the Miochol."

Dr. Osher has performed phacoemulsification on approximately a dozen patients with IFIS, and says, "I have not had to rely on either iris hooks or a mechanical device for pupil dilation."

Multicenter Study Started

"We don't really know whether IFIS will be associated with a higher rate of cataract surgical complications now that ophthalmologists can foresee and anticipate the problem," says Dr Chang. "For this reason, we've started a multicenter prospective study to assess what the complication rate of IFIS will be, as long as the surgeon is prepared and able to use alternative pupil management strategies such as those we describe. We plan to enroll up to 150 consecutive Flomax patients at 11 sites across the country."

 

 
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