Macular Proliferative Vitreoretinopathy

Proliferative vitreoretinopathy (PVR) is a disease characterized by the growth and contraction of cell membranes both on the retinal surface and intraretinal layers, being a post-surgical complication that can compromise vision permanently if not treated. Recent reports have showed that postoperative premacular membranes are a localized presentation of proliferative vitreoretinopathy. A specific subtype of this entity has been identified as macular proliferative vitreoretinopathyMacular proliferative vitreoretinopathy (mPVR), which etiology can be idiopathic or secondary to multiple surgical procedures. Short-term mPVR is a different entity from macular puckerMacular pucker in terms of rapid development, structural distortion, histopathological findings and visual compromise. OCT examination of eyes with mPVR shows hyperreflective membranes that are thicker than observed in ERM, sometimes doubling the thickness of the retinaRetina, with an important distortion and disorganization of retinaRetina layers; macular edemaMacular edema with cystic spaces is a common finding. Histopathological analysis shows some differences with epiretinal membranesEpiretinal membrane (ERM). Idiopathic ERM are composed of myofibroblasts, glial cells, and fibroblasts, while PVR membranes are composed predominantly of retinal pigment epithelial (RPE) cells, glial cells, and myofibroblasts. Cell transdifferentiation into myofibroblasts represents an important process in pathogenesis of both entities, while RPE cells are more predominant in mPVR. Many intraocular and paraocular medical treatments have been attempted to treat mPVR, but none of them have been successfully reproduced or have led to a better visual outcome compared to surgical management. The first-line treatment is an early surgical peeling of the preretinal membrane altogether with the internal limiting membrane (ILM)Internal Limiting Membrane (ILM) of the posterior retinaRetina to release the traction and the consequent anatomical structural alteration that this entails. A delayed surgery may imply a permanent loss of vision. In those patients that have high risk of developing mPVR it is important to perform an ILM peeling up to the temporal vascular arcades after a staining with brilliant blue, as the ILM has been shown to act as an scaffold for membrane proliferation.