ASSESSMENT OF THE SIGNIFICANCE OF CYSTIC CHANGES AFTER EPIRETINAL MEMBRANE SURGERY WITH INTERNAL LIMITING MEMBRANE REMOVAL

Purpose:To assess the prevalence and significance of cystic changes after internal limiting membrane peeling during epiretinal membrane surgery.Methods:A retrospective review was performed on 64 patients who underwent pars plana vitrectomy with membranectomy for idiopathic epiretinal membrane between January 2010 and January 2012 by a single physician. Pars plana vitrectomy alone (Group 1, n = 32) or in combination with phacoemulsification (Group 2, n = 32) was performed. Peeling of the epiretinal membrane was assisted by triamcinolone, and internal limiting membrane was peeled up to the vascular arcades with the aid of brilliant blue dye.Results:In Group 1, best-corrected visual acuity in logMAR (Snellen) improved from 0.53 0.29 (20/68) at baseline to 0.23 +/- 0.22 (20/34) at 6-month follow-up (P < 0.001). Two cases (6.3%) developed new cystic changes within the inner nuclear layer; however, there was no significant difference in best-corrected visual acuity at 6 months (P = 0.475). In Group 2, best-corrected visual acuity improved from 0.41 +/- 0.17 (20/51) at baseline to 0.18 +/- 0.15 (20/30) at 6 months (P < 0.001). Eight cases (25%) developed new inner nuclear layer cystic changes; however, there was no significant difference in best-corrected visual acuity at 6 months (P = 0.894).Conclusion:Development of new inner nuclear layer cystic changes after epiretinal membrane surgery may be a frequent finding, but in contrast to cystoid macular edema, it does not seem to affect visual recovery and should be observed. The combination of pars plana vitrectomy with cataract extraction may increase the risk of inner nuclear layer cystic changes.