In the current era where pharmacologic therapy is the preferred treatment for macular edema secondary to retinal vein occlusion (RVO), there is still a role for laser, according to Francesco Bandello, MD.
“Laser photocoagulation–especially subthreshold laserÂ–may be considered in eyes with a thinner macula (< 300 µm to 400 µm), and in patients for whom the use of intravitreal anti-VEGF or corticosteroid therapy is contraindicated or has failed to be effective,” said Dr. Bandello, professor and chairman, Department of Ophthalmology, University Vita-Salte, Scientific Institute San Raffaele, Milan, Italy.
“Laser may be used in combination with pharmacotherapy to stabilize the results of the intravitreal treatments,” Dr. Bandello added. “Selective laser ablation of peripheral retinal ischemia as a means to improve macular edema is topic of intense interest, but further study is needed to determine if there is a benefit for laser treatment.”
Dr. Bandello reviewed published studies investigating laser treatment for RVO-related macular edema. Information on use in eyes with central RVO (CRVO) comes from the Central Vein Occlusion Study [Ophthalmology. 1995;102(10):1425-1433] that randomized participants to macular grid laser photocoagulation or no treatment. During follow-up to 3 years, visual acuity outcomes did not differ between groups even though laser treatment significantly improved macular edema.
Outcomes of laser treatment were better in eyes were BRVO, according to results from the Branch Vein Occlusion Study [Am J Ophthalmol. 1984;98(3):271-282]. In that randomized, controlled trial, the laser-treated eyes gained an average of 1.3 lines of visual acuity, which was statistically significant compared with the untreated controls, and 65% of laser-treated eyes achieved an improvement of at least 2 lines.
“The visual function improvement with laser treatment was seen mostly in patients who were younger and who had less edema,” Dr. Bandello said.
He also noted that in a study of patients with macular branch retinal vein occlusion (BRVO), there was no significant difference in visual acuity outcome in patients randomized to early or delayed grid laser treatment compared with observation [Graefes Arch Clin Exp Ophthalmol. 1999;237(12):1024-1027].
“Macular BRVO is a specific kind of BRVO that is associated with less vision loss and usually a better prognosis,” Dr. Bandello said. “In these eyes, it is not necessary to treat with laser.”