Pearls for managing the nanophthalmic eyes during cataract surgery

February 22, 2006

Challenging phacoemulsification cases can present problems for the cataract surgeon. How a surgeon manages those challenging cases can prevent the case from turning into a nightmare.

Challenging phacoemulsification cases can present problems for the cataract surgeon. How a surgeon manages those challenging cases can prevent the case from turning into a nightmare.

Rosa Braga-Mele, MD, of Canada offered some pearls for managing the nanophthalmic eye Wednesday at the World Ophthalmology Congress. Dr. Braga-Mele says the nanophthalmic eye is a very challenging eye to address because so much can go wrong, so quickly.

"So, you have to have multiple steps ready," she said. "They are a choroidal hemorrhage waiting to happen."

Dr. Braga-Mele said the smaller eyes, regardless of whether they are nanophthalmic or not, tend to be less than 19 mm. These eyes give surgeons the most problems. The eyes tend to be hyperopic and poorly dilated.

The key in addressing these cases is to remember that surgeons are dealing with a shallow anterior chamber with a small pupil. There is not a lot of room to work within these eyes. Many of these cases may or may not have glaucoma, with or without iridotomy.

The general surgical approach for small or shallow eyes is to use a wire lid speculum for more room. Surgeons should use a temporal approach with a clear corneal incision, and use topical anesthesia.

"You (also) want to perform a longer tunnel on these patients because you want to have a lesser chance of having the iris shooting out at you," added Dr. Braga-Mele.

Other pearls for such cases are: raise the bottle height for more pressure into the eye and to sustain the anterior chamber; use a super ophthalmic viscophthalmic device (OVD) because they will compartmentalize the anterior chamber and make it easier to work within that chamber.

Dr. Braga-Mele urges surgeons to perform the phacoemulsification in the capsular bag as much as possible. "That's a toss up because you're either too close to the endothelium or you're too close to the posterior capsule. I am not sure which is worst, but try to stay within the bag."

Dr. Braga-Mele offered some tips to reduce the positive pressure, which causes these shallow anterior chambers. Surgeons can perform perioperative ocular compression; use topical betaxolol, or try a dehydration of the vitreous.

At times these techniques will work and will deepen the chamber. When they don't work, Dr. Braga-Mele suggests that the surgeon get into the anterior chamber and deepen it with an OVD.

When all else fails, Dr. Braga-Mele said she would perform a vitreous tap with a pars plana approach. She has used a 21-gauge needle, but she has switched to trans-conjunctival vitrectomy technique with a 25-gauge needle (and you don't need a suture).

"Again, in these patients, you have to beware of choroidal hemorrhage," said Dr. Braga-Mele.