Working through small pupils during cataract surgery must be as frustrating as trying to squeeze a profit out of what Medicare pays your facility to host the case. Reimbursements certainly aren't going to increase anytime soon and inadequate intraoperative mydriasis is becoming an increasingly common problem, so team up with your surgeons to find a cost-effective way to dilate pupils and dial up revenues.

A growing number of cataract patients are showing up with small pupils in part because more male patients are using prostate medications, which affect the iris dilator muscle. Intraoperative floppy iris syndrome (IFIS) occurs in at least 75% of men on those medications and in as much as 25% of the general patient population, says Steven Silverstein, MD, FASC, an ophthalmic surgeon in Kansas City, Mo. Plus, there are plenty of patients whose pupils don't dilate fully or don't dilate to the extent that they did during pre-op clinic visits.

Maintaining pupillary dilation improves access to the eye and visualization of delicate anatomy, factors that decrease risk of posterior capsular tears, zonular damage and vitreous loss, and make cataract removal easier and safer. It also lets surgeons perform complex cases more efficiently. Surgeons have plenty of available options to keep pupils dilated during surgery, from hooks and rings to pharmaceutical agents. The optimal choice for your facility demands striking a balance between cost and clinical efficacy.

• Iris hooks. Reusable iris hooks don't add to case costs, but the initial capital expenditure will run your facility a couple hundred dollars. A small stab incision is made in the limbus, through which surgeons insert 4 hooks to maintain pupil dilation. In patients with IFIS, the iris tends to prolapse out of the wound, which can be prevented by placing the hooks in a diamond configuration underneath the main temporal incision, says ophthalmic surgeon Nick Mamalis, MD, co-director of the Intermountain Ocular Research Center in Salt Lake City, Utah.
• Iris rings. Single-use rings cost approximately $125 and reusable options run approximately $50 per use. Surgeons insert ring-type devices through a clear corneal incision to create and maintain pupil dilation. There are several models available that are largely effective in giving surgeons the space they need to operate. Surgeons must decide which design and delivery method — a circular or square dilation and inserter or separate injector — works best in their hands. During surgery, surgeons must be aware of the ring's position on the pupil, so they don't dislodge the device when sliding instruments into and out of the eye.

Jeffrey Whitman, MD, president and chief surgeon at the Key-Whitman Eye Center in Dallas, Texas, says one-third of his patients have pupils that don't fully dilate. In those cases, he employs a single-use ring that gives him plenty of room within the eye to manipulate instruments. He places the device over the iris, so he's not stretching delicate eye anatomy during insertion or mangling the iris during removal.

• Pupil dilators. Dr. Whitman can also reach for a reusable pupil dilator, which costs about $400. He inserts the instrument through a small incision and pushes a plunger to activate prongs, which engage the margins of the pupil. The dilator cuts down on case costs once it's been paid for, but Dr. Whitman cautions that the device doesn't match the performance of ring devices with respect to post-op cosmesis of the iris. He also points out that the dilator is removed for the remainder of the procedure once the pupil has been expanded. That, he says, increases the risk of sucking up the edge of the iris during aspiration of cortical material.
• Intraocular pharmacologic dilation. Surgeons often inject an epinephrine-lidocaine mixture into the anterior chamber to initiate pupil dilation with the hope that the injection will keep the pupil from constricting during surgery, says Dr. Mamalis. However, he says, surgeons are discovering that IFIS and pupillary constriction can still occur even when intracameral epinephrine is used. Surgeons in England have found that intracameral ?phenylephrine injections administered at the beginning of a case lets them perform surgery without using rings to maintain mydriasis, adds Dr. Mamalis.

Dr. Whitman uses a compounded mixture of phenylephrine and lidocaine. Phenylephrine effectively dilates the pupils, even in patients with IFIS and those on medications that can cause pupils to constrict. The phenylephrine-lidocaine compound provides a continuous pharmacologic dilation that does not need to be supplemented, says Dr. Whitman. The cost of pharmacologic options varies depending on volume and the compounding pharmacy you order from, but Dr. Whitman says a single-dose vial of phenylephrine-lidocaine costs his facility $17.

What's safe surgery worth?

The expense of maintaining pupil dilation is important, especially in a specialty with razor-thin profit margins. But it's equally important to look beyond supply expenses when it comes to managing mydriasis. Dr. Whitman says managing case costs is always in the back of his mind, but not at the expense of poor outcomes. He always errs on the side of caution when deciding if a pupil-expanding device is needed. He also says the devices let him take on difficult cases he would otherwise not attempt and helps keep the surgical schedule on track when he's faced with a complex cataract.

The bottom line goes beyond the bottom line. "Managing small pupils is not solely about a cost-benefit analysis," says Dr. Silverstein. "It's primarily about patient safety." OSM