Q: I occasionally send out cataract patients whose pupils don't dilate well. Will this interfere with a successful outcome?
A: Yes, a poorly dilating pupil can cause several problems intraoperatively, says Lawrence Woodard, M.D., corneal and cataract surgeon at Omni Eye Services, in
One specific pupil problem is intraoperative floppy iris syndrome (IFIS). "In cases of IFIS, not only does the pupil not dilate well, but it begins constricting during surgery," Dr. Woodard says. "As the name indicates, the iris loses tone and becomes very floppy. And then it releases prostaglandins into the anterior chamber, which is what stimulates the pupil to constrict."
An expansion ring helps when a cataract patient has a poorly dilating pupil.
Courtesy: Lawrence Woodard, M.D.
The culprit: Flomax (tamsulosin, Boehringer-Ingelheim Pharmaceuticals) as well as similar drugs used to treat enlargement of the prostate. In one prospective study, 90% of patients taking Flomax exhibited some degree of IFIS during cataract surgery.1
Flomax isnt the only cause of poorly dilating pupils, though. Other causes: use of miotics (such as pilocarpine) for glaucoma; posterior synechiae from previous ocular inflammatory disease; fibrotic pupillary sphincter muscle; pseudoexfoliation; and diabetes-related ocular conditions, such as rubeosis or neovascular glaucoma.
During the procedure, the surgeon can make several adjustments for a poorly dilating pupil. First, Dr. Woodard says, the surgeon can place the clear corneal incision more anteriorly, further away from the surgical limbus, to help prevent the iris from getting entrapped in the wound.
Second, the use of intraocular epinephrine during surgery helps to dilate the pupil and also increases iris tone.
Third, "I use a higher viscosity viscoelastic, which tamponades the iris a little more and helps keep it better dilated than the standard viscoelastics."
If the pupil still remains small, then the surgeon may use an expansion device, such as a Malyugin ring (MicroSurgical Technology), to physically maintain pupil dilation.
Q: What can I do before sending the patient to the surgeon? What should I look for when I see these patients postoperatively?
A: Preoperatively, the O.D. can do several important things, Dr. Woodard says. For one, place the patient on atropine (or another mydriatic) for three to seven days before surgery. This, combined with epinephrine during the cataract procedure, can significantly reduce the risk of IFIS.2
Next, ask the patient's primary care doctor about temporarily discontinuing Flomax before surgery, which can help decrease iris movement and pupillary constriction. "Not every patient can stop it, and not every eye surgeon believes that stopping it helps," Dr. Woodard says.
Last, but most important, counsel patients that the surgery may be more complicated, recovery may be more prolonged, and there is an increased risk of complications.
Postoperatively, these patients may have more inflammation during the first few days after surgery. And, in IFIS cases, the intraocular pressure may be slightly elevated because some viscoelastic may be retained in the anterior chamber.
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If the patient has a lot of corneal edema or if their pressure is high, they need to be seen again earlier than the standard patient," Dr. Woodard says. "But if there are no major issues, they don't need to come back any sooner than the typical cataract patient."
1. Chang DF, Osher RH, Wang L, Koch DD. Prospective multicenter evaluation of cataract surgery in patients taking tamsulosin (Flomax). Ophthalmology. 2007 May;114(5):957-64.
2. Masket S, Belani S. Combined preoperative topical atropine sulfate 1% and intracameral nonpreserved epinephrine hydrochloride 1:4000 for management of intraoperative floppy-iris syndrome. J Cataract Refract Surg. 2007 Apr;33(4):580-2.
