Surgical macular decompression for macular edema in retinal vein occlusion

BACKGROUND: Recently, a number of surgical and laser approaches have been used to improve visual outcome in cases of central retinal vein occlusion (CRVO) and branch retinal vein occlusion (BRVO). Intravitreal steroid injection alone appears to offer only temporary improvement at best. Radial optic neurotomy for CRVO and arteriovenous adventitial sheathotomy for BRVO are the most frequently utilized surgical procedures for these conditions, but evidence regarding efficacy is still lacking. We have suggested that macular decompression by internal limiting membrane (ILM) peeling may reduce macular edema and hemorrhage and improve visual acuity by relieving elevated intraretinal tissue pressure and facilitating egress of blood and extracellular fluid out of inner retinal layers into the vitrectomized vitreous cavity. METHODS: 50 cases of severe visual loss due to macular edema caused by CRVO or BRVO, not eligible for laser photocoagulation, underwent pars plana vitrectomy with removal of preretinal hyaloid, peeling of the ILM stained with indocyanine green dye, air-fluid exchange, and postoperative prone positioning. RESULTS: In all cases, intraretinal blood and retinal thickening diminished within 6 weeks of surgery. Visual acuity improved in 87% of CRVO cases and 68% of BRVO cases. Vision improved and stabilized at 39 days after surgery. Average improvement was 2.6 lines with a 6-line improvement in 1 case. There was no difference in outcome between cases with ischemic or nonischemic features on fluorescein angiography. INTERPRETATION: Macular decompression using vitrectomy and ILM peeling is effective in the treatment of severe visual loss due to macular edema in CRVO and in those BRVO cases that do not qualify for laser photocoagulation.