When a patient has a small pupil due to rubeosis iridis from neovascular disease, how do you handle it during cataract surgery?
Neovascularization and scarring of the iris in a patient with proliferative diabetic retinopathy.
In the case presented here, a 60-year-old patient had a history of proliferative diabetic retinopathy including rubeosis iridis and neovascularization of the angle. She responded well to panretinal photocoagulation laser as well as intravitreal injections of anti-VEGF medications. The neovascularization had regressed, leaving a scarred iris and a tonic pupil of approximately 4 mm in diameter. She now required cataract surgery.
In most cases, small pupils can be stretched to allow expansion to a size sufficient for routine cataract surgery. But in this case, there was a risk that stretching the pupil may rupture some of the rubeotic vessels of the iris. While these vessels were mostly regressed and fibrosed, there was a risk of vascular rupture and bleeding.
And to top it off, the patient was already on warfarin as a blood thinner because of her atrial fibrillation.
I found that the solution was for me to work through the small pupil and not stretch it. The patient's 4-mm pupil was sufficient to perform a 5-mm capsulorrhexis, and then the nucleus was chopped using a vertical chop technique. This technique allowed for placement of the phaco probe and the chopper within the central 4 mm of the nucleus so that everything was visible. Using a horizontal chop technique would have required placing the chopper around the nucleus periphery, which was not visualized.
With the nucleus chopped into quadrants, it was removed and then the cortex was aspirated. A three-piece acrylic lens with a 6-mm optic was placed in the capsular bag and rotated to help free any residual cortex. At the end, the chopper was used to lift
up and peek under the iris to ensure complete cataract removal. The patient did well and is now following up with her retinal specialist.
See Dr. Devgan share more expert insight live at OSN New York 2010, to be held November 19-21, 2010 at the Sheraton New York Hotel & Towers. Learn more at OSNNY.com.