As reported in 2005 by David F. Chang, MD, and John R. Campbell, MD, the pupil often dilates poorly in patients taking alpha-1 blockers; IFIS is characterized by iris billowing and floppiness, iris prolapse, and progressive constriction of the pupil. These problems increase the incidence of posterior capsule rupture—particularly when the surgeon has not anticipated IFIS.1
Dr. Chang, a clinical professor at the University of California, San Francisco, and in private practice in Los Altos, Calif., notes that once the connection between floppy iris and Flomax became clear, ophthalmologists voiced many different opinions about how to manage the syndrome. "The most important lesson here is that clinicians need to question patients preoperatively about current or prior alpha-1 blocker use," says Dr. Chang. "Then they can be better prepared to manage the iris intraoperatively. A second important point is that the popular mechanical pupil stretching technique is ineffective for IFIS—it can exacerbate the problem."
|A Morcher pupil expansion ring is used to hold a pupil affected by IFIS open wide during cataract surgery.|
David F. Chang, MD
As additional reports of IFIS surgical complications appeared, the question of how to advise urologists arose. "Some ophthalmologists suggested that patients should not be treated with Flomax until after they'd had their cataracts removed," notes Dr. Chang. In order to determine whether a change of this magnitude was really necessary, Dr. Chang organized a multicenter, prospective study of Flomax patients undergoing cataract surgery, to see whether their surgeries would be negatively affected when the surgeon knew that IFIS was a potential problem.
The 10 surgical practices in the study monitored 169 consecutive Flomax patients over a seven-month period, tracking outcomes and complication rates. The surgeons were allowed to choose any one of four surgical strategies to manage IFIS—preoperative atropine, Healon 5 viscomydriasis, pupil expansion rings or iris retractors. "We found a very low complication rate, with less than 1 percent posterior capsule rupture," says Dr. Chang. "In short, the data suggest that if the surgeon can anticipate when IFIS is likely to occur, he or she can use an alternate pupil management strategy and obtain excellent results." Dr. Chang will be presenting the complete results of the study at this year's American Society of Cataract and Refractive Surgery meeting.
Choosing a Management Strategy
Because a number of strategies can be used to manage IFIS intraoperatively, we asked several surgeons to talk about their experience using the different options. "Currently, management strategies can be divided into three broad categories," explains Dr. Chang. "One is pharmacologic—manipulation of the iris using either preoperative atropine or intracameral epinephrine or phenylephrine. Another technique involves using Healon 5 for viscomydriasis, sometimes in conjunction with a dispersive agent to retard its evacuation. The third category is the use of devices to hold the pupil open, such as a pupil expansion ring or iris hooks."
Dr. Chang says it's important for surgeons to recognize that IFIS can be mild, moderate or severe, because a technique that works in a mild IFIS case may not work as well if the problem is severe. "In a mild case, the pupil may dilate quite well despite Flomax use," he observes. "In these cases there's not a lot of tendency for iris prolapse, and not much constriction; any of the techniques may work well, including atropine and Healon 5. In a severe case, however, there's a strong tendency for prolapse and the pupil constricts very quickly. Atropine doesn't really work well for these eyes."
Dr. Chang notes that preop dilation may provide a good clue about which level of IFIS you're dealing with. "If the pupil is very small preoperatively, you should anticipate severe IFIS, and I would favor iris retractors for these cases," said Dr. Chang. "I also use iris retractors instead of Healon 5 if the nucleus is brunescent because of my preference for using high vacuum with these eyes."
Joel Shugar, MD, MSEE, medical director and CEO of Nature Coast Eyecare Institute in Perry, Fla., says the idea of using epinephrine to combat iris floppiness caused by IFIS occurred to him in June 2005.
"Basically, Flomax is an alpha-1 adrenergic blocker," he explains. "Epinephrine is adrenaline, which is the molecule that Flomax blocks. So it occurred to me that using epinephrine intracamerally in a very high concentration might be enough to overcome that blockade. Instead of trying to make an end-run around the problem by using either hooks or Healon 5 to deal with a floppy iris, this addresses the problem directly: It makes the iris stop being floppy.
"Once I had the idea," he continues, "I used a pH meter to check the acidity of American Reagent non-preserved, bisulphite-free 1/1000 epinephrine. By itself it had a pH of 3.13, sufficiently acidic to damage the endothelium. However, diluting it three-to-one with a mixture of three parts BBS-plus to one part 4% nonpreserved lidocaine, or 'Shugarcaine,' brought the pH up to 6.9. We call the mixture 'epi-Shugarcaine.' "
Dr. Shugar says this solution is ideal for him because he uses Shugarcaine as an intracameral anesthetic in nearly every case. "I'm adding the epinephrine to what I'm going to be injecting anyway," he explains. He adds that he injects the mixture before the viscoelastic, because viscoelastic can cause a painful retrodisplacement of the lens-iris diaphragm; injecting the anesthetic first prevents the patient from experiencing pain.
Asked how much needs to be injected, Dr. Shugar says that under ordinary circumstances he might use
0.5 cc of the BSS/lidocaine mixture, but to prevent IFIS he injects 1 to 2 ccs of the epi-Shugarcaine. "This quantity always seems to be effective," he says. "I wait about 30 seconds before putting in the visco. The iris loses its flaccidity or floppiness very quickly, and additional dilation occurs during the next one to two minutes, generally making the pupil 1 or 2 mm larger than it was before."
Dr. Shugar agrees with Dr. Chang that IFIS can be mild, moderate or severe, but says that in all of the cases in which he's used this strategy to manage the symptoms (approximately 20 cases at the time of this interview), it has been completely effective. "All of the eyes that I've done had crystal-clear corneas the next day, with 20/10 or 20/15 vision," he says. He adds that he has posted his results on the ASCRS Internet discussion group, and 10 or 15 additional cases have been reported by other surgeons. "In all but one of them, this strategy was effective. In the one case in which it wasn't effective, the patient had a maximum pupil size of 2.5 mm before the epinephrine, which could indicate that some extra unknown factors were involved.
"In my experience, this approach seems to be the answer," he says. "And epinephrine has the advantage that it can be instilled at any time during a case, so if you're surprised by symptoms suddenly appearing, you can deal with it and proceed."
Dr. Chang agrees with the latter point, noting that in some cases the pupil is reasonably well-dilated initially, but following hydrodissection the pupil suddenly constricts. "In this situation, where the capsulorhexis makes it more difficult to place expansion devices, I've found that intracameral epinephrine can really help," he says. Dr. Chang notes that in this situation iris retractors are still an option, but advises caution: "If you do need to use iris retractors after completion of the capsulorhexis, I'd recommend using a second instrument like a Lester hook to push the pupil margin away from the capsulorhexis edge. That way you can be absolutely certain that you're hooking the iris and not the 'rhexis with the iris retractor."
Dr. Shugar says he's not aware of any downside to using epinephrine to manage IFIS. "The epinephrine allows the vast majority of cases to be treated as standard cataract surgery, as if the patient had never used Flomax," he says. He notes that it's also cost-effective, with epinephrine costing less than a dollar a bottle. "I'm sure there will be a few cases that require Healon 5 or iris hooks, but if you can prevent a large percentage of those, I think that's a great solution."
|Injecting Healon 5 into an IFIS eye will dilate an undilated pupil and keep the iris away from the cornea. However, it may necessitate changes in capsulorhexis technique.|
Douglas D. Koch, MD
Samuel Masket, MD, clinical professor of ophthalmology at the Jules Stein Eye Institute, UCLA School of Medicine, says that when first confronted with IFIS, one thing became apparent to him. "In addition to the tendency for the iris to billow and try to escape through incisions during surgery," he says, "the pupil became progressively smaller. The dilator muscle is weakened by the alpha-1 blocker, so it doesn't have as much counter-traction against the pupil's tendency to become miotic." Dr. Masket realized that the pupil coming down was the biggest part of the problem. "If the pupil stays widely dilated, it keeps the iris tissue out of the way of the emulsifying probe. Iris floppiness doesn't become as manifest, and we tend to not have any problems.
"Traditional cycloplegics and iridoplegics, such as Mydriacyl [tropicamide] or Cyclogyl [cyclopentolate], don't have the same iridoplegic strength as atropine," he continues. "So it made sense to use atropine to block the pupil as much as possible to counteract the progressive miosis. This has no effect on the billowing of the iris, but by keeping the pupil as dilated as possible, its less likely that the iris will interfere with removing the cataract." So, Dr. Masket says he began having Flomax patients use one drop of atropine 1% three times a day for the two days before surgery, and once again on the day of surgery.
Dr. Masket says the size of the pupil at the beginning of surgery determines how he will proceed. "If the patient comes into surgery with a pupil dilated in excess of 6 or 7 mm in response to atropine and the other iridoplegic agents administered prior to surgery, the pupil will generally not come down during the procedure," he explains. "In this case, I start the surgery without the use of hooks and anticipate that the surgery will be nearly routine. If the patient has less than
6 mm of dilation, I use iris hooks from the beginning and surgery tends to progress routinely. Should the pupil become progressively smaller during surgery, then I'll stop and place iris hooks, or if available, switch to the Healon 5 method." [For more on this, see below.]
|Reusable iris retractors can be placed in a diamond configuration. Because an IFIS pupil is very elastic, even maximal stretching doesn"t cause sphincter damage. |
David F. Chang, MD
Dr. Masket notes two potential drawbacks to using atropine for this purpose. "First," he says, "a patient who has very reduced bladder function or a very enlarged prostate could go into acute urinary retention if the Flomax is stopped and atropine is applied topically. For that reason, it's essential that the Flomax be continued. In any case, we know that stopping Flomax is of little or no benefit in terms of reducing IFIS." He notes that patients who have stopped Flomax have either had prostate surgery or are on another medication.
"The only other drawback is very minor, and that is that there's a tendency for the patient to stay dilated anywhere from four to 10 days after surgery," he continues. "We do like to have the pupil return to normal as quickly as possible to aid visual function. However, this is relatively unimportant because the patient is pseudophakic at this point, so the loss of focusing isn't really a problem. Also, these patients tend to return to normal dilation more quickly than patients using atropine who haven't been on Flomax."
Dr. Masket says he suspects atropine may not be able to overcome the tendency of the pupil to get smaller during surgery when a patient has a complete or near-complete alpha-1 blockage at the dilator muscle. "However, if the blockage is less than 100 percent," he says, "atropine can be a very effective adjunct, and surgery can be routine, or nearly routine. I've used this approach on roughly 20 cases; about two-thirds did not require the use of iris hooks."
Douglas D. Koch, MD, professor of ophthalmology at Baylor College of Medicine in Houston, prefers using Healon 5 to control the iris when confronted with IFIS. "Healon 5 has the highest viscosity of any of the available viscoelastics," he says. "Injected into an IFIS eye it will dilate an undilated pupil and keep the iris away from the cornea. As long as it's not aspirated, Healon 5 does a wonderful job of preventing the iris from billowing, prolapsing and otherwise misbehaving."
Dr. Koch says he uses Healon 5 during the entire case, but he acknowledges that some surgeons don't like to use it during capsulorhexis. "It's difficult to do a needle capsulorhexis with Healon 5," he says, "because its hard to fold the capsule over and drag it through the highly viscous material. Capsulorhexis forceps work better under these conditions. Likewise, for hydrodissection you have to create a little path so the fluid can exit; otherwise it can build up in the capsular bag, creating a capsular block that can jeopardize the posterior capsule."
Dr. Koch says it's not necessary to use Healon 5 exclusively to make this work. "If the pupil is adequately dilated at the outset, you can use whatever viscoelastic you're accustomed to in the initial phases of the surgery," he explains. "Also, if you're not comfortable doing your 'rhexis and hydrodissection under Healon 5, you can use a soft-shell technique in which the Healon 5 is injected more anteriorly to protect the cornea, while you place something beneath it that's much less viscous, possibly even BSS."
Disassembling the Nucleus
For many surgeons, the hard part about using Healon 5 is disassembling the nucleus without being able to use high flow and vacuum. "When you're doing phacoemulsification under Healon 5 you need to keep your parameters at modest levels to prevent aspiration of the viscoelastic," admits Dr. Koch. "I've found it effective to keep the vacuum at 215 mmHg or lower, with a flow rate no higher than 25. I usually keep it around 20.
"To disassemble the nucleus under Healon 5," he continues, "I like to use a modified stop-and-chop approach in which I sculpt a groove, break the nucleus in half, rotate it 90 degrees, and then mechanically break a piece off of the distal half using a Nagahara chopper and the phaco tip. I do this mechanically, without any flow or vacuum, even if I'm not using Healon 5. Then it's easy to engage that piece with the phaco tip, initiate flow and vacuum, and remove it. It's also easy to remove the remaining portion of that half of the nucleus because it can be directly aspirated, brought forward, and then chopped in a more standard fashion." Dr. Koch notes that this is a derivation of the slow-flow technique developed by Robert H. Osher, MD, but with higher settings.
"When you use higher flow and vacuum settings to remove the cortex, you may aspirate some of the Healon 5, causing the pupil to come down," notes Dr. Koch. "This can be disconcerting or even alarming for the surgeon. But all you have to do is reinject the H5 and the pupil comes right back up." Dr. Koch says that he avoids this problem by using bimanual irrigation and aspiration, which makes it easy to get under the capsule and remove cortex from any quadrant, even if the pupil is relatively small.
Dr. Koch adds one important caveat about using Healon 5. "You must go underneath the implanted intraocular lens to remove it," he says. "I always use a coaxial irrigation and aspiration handpiece to do this. Using this technique, you can readily see the Healon 5 being removed. In my experience, other techniques are not sufficiently reliable."
An Effective Alternative
Overall, Dr. Koch says that having to use low flow and aspiration hasn't been an impediment. "It's tougher if you're dealing with a denser nucleus," he admits, "but once you get that first crack, everything's fine. You just have to proceed slowly and cautiously."
Dr. Koch acknowledges that if Dr. Shugar's epinephrine system is as effective as injecting Healon 5, it would be easier for many surgeons because it doesn't require altering the flow and vacuum settings a surgeon may prefer to use. "I think the epinephrine approach is worth trying," he says, "although I have a feeling there will be eyes in which it won't work. In some cases the dilator muscle may have atrophied so much that there won't be enough muscle left to stimulate.
"I like the Healon 5 approach because to me it's faster and at least as safe as using any of the other options," he continues. "I proceed with very little delay even though the settings are reduced somewhat, and the Healon 5 always leaves a beautiful, round pupil. Iris hooks are fine, but they take a fair amount of time to insert and position, and in 25 cases I've never had to resort to them. Healon 5 is also less expensive because it simply involves substituting one viscoelastic for another.
"Healon 5 has been very effective in my hands," he concludes. "It's worked every time."
Rings and Retractors
Dr. Chang talked about his experience using pupil expansion rings and iris retractors. "Three companies make pupil expansion rings," he says. "Morcher and Milvella make plastic rings. You need a special injector to insert them, which is costly but reusable. Another alternative, the Graether Pupil Expansion System from Eagle Vision, is made of silicone and comes with a disposable injector system."
Dr. Chang says he's used all three rings, and they all work very well for IFIS. He notes, however, that there are two situations in which pupil expansion rings can be difficult to insert. "One is when the patient has a shallow anterior chamber," he explains. "The other is when the pupil is so small that it makes threading the expansion ring into place overly difficult and traumatic. In those situations, iris retractors are much easier to use." Dr. Chang also notes the fact that the surgery center is not reimbursed for these devices has probably limited their popularity.
Dr. Chang's current preference is to use iris retractors. "I place them in a diamond configuration," he notes. [See photo, page 62.] "I insert one through a stab incision just posterior to the clear corneal phaco incision, as previously described by Drs. Oetting and Omphroy.2 This pulls the iris downward and out of the way, increasing the exposure right in front of the incision.
"With practice, you can insert and remove iris retractors very quickly," he says. "I find that it adds minimal time to the case, while making the entire procedure easier and stress-free. Unlike using Healon 5 to manage the iris, this technique allows you to employ high vacuum, and the pupil expansion is 100-percent reliable."
Dr. Chang observes that surgeons sometimes hesitate to use iris hooks for fear of damaging the iris sphincter. He says that although that can happen when a fibrotic pupillary margin is subjected to excessive stretching with iris retractors, it's not a problem in this situation. "With IFIS the pupillary margin is very elastic and not fibrotic," he says. "You can stretch it maximally and it doesn't cause permanent sphincter damage or permanent mydriasis."
In terms of which iris retractor Dr. Chang prefers to use (he has no financial interest in any of them) he notes that disposable retractors made of nylon have been available for many years, but he now prefers reusable, autoclaveable polypropylene iris retractors, such as those available through FCI and Katena. "These are a little thicker and stiffer than the nylon retractors, but still flexible, like an IOL haptic," he notes. "That's what makes them more durable and allows you to keep reusing them. It also makes them easier to handle and insert, and it's easier to hook the pupillary margin because they're slightly more rigid than the nylon ones." He adds that being reusable helps to make the polypropylene retractors cost-effective.
Is One Method Preferable?
"When dealing with IFIS, it's common sense that you want the pupil to remain as dilated as possible," notes Dr. Chang. "But right now, which option you use to accomplish that is a matter of personal preference. We don't have any studies that say you get better outcomes with one technique or the other."
Dr. Masket adds that in his view, the use of any of these agents does not preclude the use of any of the others. "Atropine blocks the sphincter muscle," he says. "Epinephrine stimulates the dilator muscle. The hooks and Healon 5 are mechanical devices that hold back the sphincter of the iris and tampanade the movement of the peripheral iris tissue.
"Iris hooks and Healon 5, used correctly, will work 100 percent of the time," he continues. "The pharmacologic agents won't work 100 percent of the time, but they may prevent the need for the hooks or Healon 5, which add significantly to the expense of the surgery. The bottom line is that they can all be used in conjunction with one another. They're all part of the armamentarium."
1. Chang DF, Campbell JR. Intraoperative floppy iris syndrome associated with tamsulosin. J Cataract Refract Surg. 2005;31:4:664-73.
2. Oetting TA, Omphroy LC. Modified technique using flexible iris retractors in clear corneal cataract surgery. J Cataract Refract Surg 2002;28:4:596-8.