EyeWorld India March 2014 Issue

March 2014 14 EWAP FEAturE Phaco in post-vitrectomy cases by Vanessa Caceres EyeWorld Contributing Writer Tips and pearls to remember when performing phaco in post-vitrectomy eyes W hen performing phaco in post- vitrectomy eyes, surgeons may want to use caution. Suber S. Huang, MD , professor and vice-chair, Department of Ophthalmology and Visual Sciences, Case Western Reserve University, and director, Center for Retina and Macular Disease, University Hospital Eye Institute, Cleveland, Ohio, U.S.; Nicole Fram, MD , Advanced Vision Care, Los Angeles, Calif., U.S.; Clinical Instructor, Jules Stein Eye Institute, UCLA, Los Angeles, Calif., U.S.; and Rosa Braga-Mele, MD , Professor of Ophthalmology, University of Toronto, and director of cataract surgery, Kensington Eye Institute, Toronto, Canada, commented on tips for doing phaco in post- vitrectomy cases. Risk of complications Dr. Huang said there is no evidence to conclusively support that there is a greater risk of complications in patients who have previously undergone vitrectomy surgery. “Modern phaco techniques limit stress on the lens-iris complex and minimize fluidic surge,” he said. “Whether the vitreous plays a role in stabilizing the posterior capsule is also unclear.” However, he did say that there is a good chance that capsular AT A GLANCE • A lack of support from the vitreous could cause a deepening of the anterior chamber in eyes that have previously undergone a vitrectomy. • Be aware of zonular weakness when performing phaco in post-vitrectomy eyes, and use techniques that limit zonular stress and stabilize the capsule should be employed. • Lowering the bottle height could help with optimizing fluids. Iris repulsion syndrome or reverse pupillary block caused by fluid misdirection in a post- vitrectomy eye undergoing cataract surgery Lowering the bottle height and using a second instrument placed under the iris to release the iris from the anterior capsule Source (All): Nicole Fram, MD hypermotility can increase the risk of capsular tears, CME, dislocated lens fragments, and retinal tear/ detachment. “Rapidly progressive cataracts following pars plana vitrectomy and use of intraocular gas or silicone oil can be a special challenge if unanticipated.” Dr. Huang noted that historically, it has been thought that there is a higher risk for complications when performing cataract surgery in eyes that have previously undergone vitrectomy or retinal procedures. “Wide incision techniques have a much greater intraoperative fluctuation of eye pressure, there is greater zonular stress as the cataract is less well supported by the anterior vitreous face, and there is the rare possibility of weakening of the posterior capsule during previous vitreous surgery,” Dr. Huang said. “If capsular rupture occurs, retained lens material commonly results in increased eye pressure, inflammation, and cystoid macular edema,” he said. Additionally, these eyes could be more prone to exacerbation of preexisting retinal disease, which could include recurrent retinal tear or retinal detachment (especially in highly myopic eyes), CME in patients undergoing vitrectomy for neovascular complications of diabetes or vein occlusion, or reopening of macular hole. “Surgeons should be mindful that cataract surgery may increase the likelihood of neovascular AMD, iris neovascularization, or neovascular glaucoma,” Dr. Huang said. Dr. Braga-Mele said that phaco in a post-vitrectomy eye presents a higher risk. This means the eye would have little or no vitreous in it. And for these cases, it is important to know that the eye would have a deeper chamber because of the lack of support.