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

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.