Incidence of postoperative cystoid macular oedema after primary posterior surgical capsulotomy during combined phacovitrectomy for epiretinal membrane and macular hole

Abstract

Abstract Objective To evaluate the risk of postoperative cystoid macular oedema (PCME) and assess the safety of primary posterior surgical capsulotomy (PPSC) during combined phacovitrectomy for epiretinal membrane (ERM) or full-thickness macular hole (MH). Methods and analysis This is a retrospective cohort study of patients who had undergone combined phacovitrectomy for idiopathic ERM or MH with or without PPSC. Primary outcome measure was the incidence of PCME at 2-month follow-up; secondary outcome measures were the incidence of PCME at 6-month and 12-month follow-up and the rate of intraocular lens (IOL)-associated complications. Results 249 eyes of 249 patients who underwent combined 23-gauge phacovitrectomy for idiopathic ERM (n=176; 70.7%) or MH (n=73; 29.3%) were included in this study. 123 eyes were treated without a PPSC (group 1) and 126 eyes with a PPSC (group 2). Across the 12-month follow-up period, new onset of PCME occurred in 7/123 eyes (5.7%) in group 1 and 4/126 eyes (3.2%) in group 2 (p=0.37). There was no significant difference in the rate of PCME between eyes that were treated for an ERM and eyes that were treated for an MH (7/176 (4.0%) and 4/73 (5.5%), respectively, p=0.74). There was no case of IOL dislocation or decentration. Conclusion PPSC during phacovitrectomy for idiopathic ERM and MH does not seem to increase the risk of PCME or IOL-related complications and prevents the need for future Nd:YAG capsulotomy, thereby reducing hospital visits, patients’ burden and costs. Our study was powered to detect a 10% higher PCME rate in the PPSC group. To detect a difference of only 5% between the two groups, a sample size of 400 per group would be required.