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

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.