The long-term anatomical and visual effect of intravitreal triamcinolone injection during vitrectomy for the treatment of idiopathic macular epiretinal membrane

Purpose: To compare the long-term anatomical and visual outcomes of patients with idiopathic epiretinal membrane (ERM) removed by vitrectomy and membrane peeling with or without the use of intravitreal injection of triamcinolone acetonide (IVTA). Methods: A retrospective chart review was performed. Subjects who underwent vitrectomy and who were followed over 12 months were included. The study included two groups of patients. In group 1 (71 eyes), the patients underwent vitrectomy and membrane peeling without the use of IVTA. In group 2 (27 eyes), 2mg of IVTA was given at the end of the surgery. The main outcome measures were best-corrected visual acuity (BCVA), central foveal thickness (CFT) determined by optical coherence tomography (OCT), the number of cataract surgeries, and the use of anti-glaucomatous drugs during the follow-up period. Results: This study included 98 eyes with ERM from 98 patients. There was no significant difference between the two groups with respect to age, gender, pre-and postoperative lens status, BCVA, CFT, or length of the follow-up period. The mean age for all of the patients was 62.45±10.01 (mean ± SD) years, and the mean follow-up length was 20.58±9.64 (mean ± SD) months. In all cases, the mean best-corrected logarithm of minimum angle of resolution (logMAR) acuity improved from a preoperative value of 0.91±0.32 [Snellen equivalent (SE), 0.16±0.14] to a postoperative value of 0.46±0.36 (SE, 0.46±0.29) (P<0.0001). The CFT was reduced from a preoperative value of 473.46±96.91 μm to a postoperative value of 302.44±69.80 μm (P<0.0001). Six patients (22.2%) in group 2 required anti-glaucomatous drugs to control intraocular pressure (IOP) during the follow-up period, and three patients (4.2%) in group 1 required drugs to control IOP (P=0.012). Conclusions: The postoperative visual outcomes for patients with idiopathic ERM were favorable, but CFT did not return to a normal level, even in eyes in which 2mg IVTA was used. The IVTA use after ERM removal produced no significant benefits during long-term follow-up, but IVTA did increase the risk of increased IOP.