Surgical posterior vitreous detachment combined with gas/air tamponade for treating macular edema associated with branch retinal vein occlusion: retinal tomography and visual outcome.

PURPOSE: To assess the effectiveness of surgical posterior vitreous detachment (PVD) together with gas/air tamponade in treating visual impairment from macular edema associated with branch retinal vein occlusion (BRVO-macular edema).
METHODS: A cohort study was conducted. To treat visual disturbance caused by BRVO-macular edema in 19 consecutive patients at a University Hospital, phacoemulsification, intraocular lens implantation, and vitrectomy were performed, together with gas/air tamponade. Patients were followed up postoperatively for 3-18 months. Foveal structure was defined using optical coherence tomography (OCT). Preoperative visual acuity, central retinal thickness, and interval between BRVO onset and operation were compared between patients with postoperative visual improvement and those without improvement.
RESULTS: Ten patients recovered normal or near-normal foveal configuration, while nine patients did not. Mean postoperative visual acuity in the former group of patients was significantly higher than in the latter. Mean foveal retinal thickness decreased significantly after the operation. The interval from onset of BRVO until operation was significantly shorter in patients with improved postoperative vision than in other patients, and patients operated on within 11 months had significantly increased postoperative visual acuity.
CONCLUSIONS: Surgical PVD and gas/air tamponade appears effective in treating BRVO-macular edema, although relatively short duration from disease onset until operation is critical for improvement of vision. When a good postoperative foveal contour is seen, it seems to be associated with better visual outcome.