Epiretinal membrane development after Ex-Press glaucoma filtration device implant: 2-year results of a case control study

Abstract

Background The most common retinal complications after glaucoma surgery are choroidal detachment, hypotony maculopathy, malignant glaucoma, vitreous hemorrhage, endophthalmitis and retinal detachment. However, if glaucoma surgery is a risk factor for the ERM development needs to be clarified. This study aims to assess the incidence of epiretinal membrane (ERM) in 2 years of follow-up in patients with primary open-angle glaucoma (POAG) treated with Ex-Press shunt implant. Methods A prospective, consecutive, single-center, case–control study. We enrolled patients affected by POAG and scheduled for Ex-Press device implant with or without concomitant cataract surgery. The control group was the contralateral eyes which continues anti-glaucomatous eyedrops. Complete ophthalmologic evaluation and spectral-domain optical coherence tomography were performed before surgery, at 6 months and 24 months of follow-up. Results Eighty-two eyes of 41 consecutive patients, 18 males and 23 females with a mean age of 70, 29 ± 8,45, were analyzed at 24 months. 39.1% of eyes developed ERM: 29.3% were cellophane macular reflex (CMR) and 9.8% were pre-macular fibrosis (PMF). In the control group, 19.5% of eyes developed ERM: 17.1% were CMR and 2.4% were PMF. No statistically significant difference was reported (p = 0.121) between treated and control group. ERM development did not affect significantly the central foveal thickness (260.13 ± 35.01 μm at baseline, 265.03 ± 34.90 μm at 6 months and 275.18 ± 33.31 μm at 24 months) and macular volume (7.75 ± 0.43 mm3 at baseline, 7.77 ± 0.48 mm3 at 6 months and 7.77 ± 0.46 mm3 at 24 months), remained comparable to reported average measures in healthy individuals during the follow-up. Concomitant cataract surgery did not increase the ERM incidence. Conclusion Ex-Press implant may increase the ERM incidence regardless concomitant cataract surgery, accelerating or inducing a posterior vitreous detachment, such as other ocular surgical procedure. Nevertheless, the vast majority of ERM are CMR, not affecting the macular profile.