Time to Foveal-Distorting Epiretinal Membrane Formation After Laser Therapy

Abstract

Purpose : Panretinal photocoagulation (PRP) and laser barricade (LB) are both commonly complicated by epiretinal membrane (ERM) formation but there is little literature on the development of a significant ERM (SERM) that distorts the foveal contour. We performed a retrospective, single-center chart review to better characterize SERM, as seen on macular ocular coherence tomography (OCT).

Methods : Charts of patients with billing codes for retinal laser therapy from 2013 through 2019 at the Gavin Herbert Eye Institute were retrospectively reviewed. Subjects with a history of autoimmune disease, uveitis, immunosuppression during or after treatment, prior laser treatment and pars plana vitrectomy, prior intraocular infection and ocular trauma, existing ERM, and less than 1 year of follow-up and inadequate imaging were excluded. Results between laser treatment groups and by ERM severity were compared using the appropriate statistical tests.

Results : A total of 72 patients and 79 eyes met study criteria with 49 patients (68%; 26 LB and 23 PRP) and 54 eyes (68%; 28 LB and 26 PRP) developing ERM (see Table 1). Median time to ERM formation was 10.5 months overall, including 11.2 months for LB patients and 9.5 months for PRP patients (p=0.45). There was a statistically significant difference in median laser energy exposure between the LB and PRP groups (8.3 J to 33.2 J for the PRP group, p<0.001). Eleven patients and 12 eyes developed SERM over a median of 30.6 months. A total of 4 eyes with LB compared to 8 eyes with PRP developed SERM (p=0.029; see Table 2). Median laser energy was 8.4 J, 19.2 J, and 26.7 J among eyes with no ERM, non-SERM, and SERM, respectively. There was a statistically significant difference in median laser energy between those with no ERM and with non-SERM (p=0.042) and between those with no ERM and with SERM (p=0.03) but not between those with non-SERM and SERM (p=0.31). Median follow-up time was 24.9 months in patients with no ERM and 59.7 months in those with SERM (p=0.045).

Conclusions : Compared to eyes treated with LB, eyes with PRP were exposed to statistically significantly more laser energy and a greater proportion of PRP eyes developed SERM. Total laser energy exposure may play a role in the develop of ERM, including membranes that distort the foveal contour. However, the results must be interpreted cautiously given the significantly shorter follow-up time in patients that did not develop ERM.

This is a 2021 ARVO Annual Meeting abstract.