Pathological Features of Epiretinal Membranes in Silicone Oil Filled Eyes

Introduction: Idiopathic epiretinal Membranes usually develop around 50 years of age and mostly formed of glial cells, RPE, and myofibroblastic tissue. Epiretinal membranes (ERM) can also develop in silicone filled eyes. The present study compared the histopathological features of both forms of membranes.

Patients and methods: The study included 16 patients with idiopathic ERM and 15 patients with silicone oil ERM (SO ERM) with history of previous par plana vitrectomy (PPV) for rhegmatogenous retinal detachment (RRD). Preoperative best corrected visual acuity; fundus examination, OCT and immunohistochemistry were done for all cases.

Result: Glial fibrillary acid protein (GFAP) % and Cluster of differentiation (CD) 68% positive cells were more in SO ERM than idiopathic ERM, in addition the central retinal thickness (CRT) and the thickness of the ERM were statistically significantly higher in SO ERM than idiopathic ERM.

Conclusion: Long standing emulsified silicone oil can result in SO ERM formation through the spongy layer that induces retinal inflammation with difficult surgical removal.