PERIPAPILLARY RETINAL NERVE FIBER THICKNESS CHANGES AFTER VITRECTOMY FOR EPIRETINAL MEMBRANE IN EYES WITH AND WITHOUT VITREOUS DETACHMENT

Purpose: To compare the changes in postoperative peripapillary retinal nerve fiber layer (p-RNFL) thickness after vitrectomy for epiretinal membrane in eyes with preexisting posterior vitreous detachment (PVD) and eyes with surgically induced PVD. Methods: This study included consecutive patients who underwent 25-gauge vitrectomy for epiretinal membrane. Eyes were divided, according to intraoperative PVD status, into a preexisting PVD group and surgically induced PVD group. Best-corrected visual acuity, p-RNFL thickness, and central retinal thickness were performed before and at 1, 3, and 6 months after surgery. Results: One hundred and twenty eyes of 120 patients were enrolled: 64 eyes in the preexisting PVD group and 56 eyes in the surgically induced PVD group. In the preexisting PVD group at 6 months, the mean global p-RNFL thickness did not change, whereas it was reduced in the temporal sector (P = 0.034). In the surgically induced PVD group at 6 months, significant decreases were observed in global p-RNFL thickness (P = 0.027), temporal (P = 0.021), temporal inferior (P = 0.030), and nasal inferior sectors (P = 0.010). At 6 months, the two groups differed significantly in temporal (P, 0.001) and temporal inferior sectors (P = 0.004). The preoperative mean best-corrected visual acuity improved significantly at 6 months in both groups. Conclusion: Postoperative p-RNFL thickness after vitrectomy for epiretinal membrane tended to decrease in the temporal sector in all eyes and in the temporal inferior and nasal inferior sectors in eyes with surgically induced PVD.