Isabela Martins Melo, MD
Vitreoretinal Fellow
University of Toronto
Dr. Isabela Martins Melo from the University of Toronto was the 2026 Macula Society’s recipient of the Evangelous S. Gragoudas award. The title of her presentation was “Assessment of Proliferative Vitreoretinopathy in Rhegmatogenous Retinal Detachment with OCT Revisiting the 1991 Retina Society Classification” and her mentor for this project was Dr. Rajeev Muni.
She presented her research on a novel conceptual framework of proliferative vitreoretinopathy (PVR) based on OCT through a prospective cohort study. She identified two main microstructural phenotypes of PVR, each associated with distinct RRD morphology. First is the subretinal (SR) subtype, which occurs in patients classified with Retina Society PVR Grade C with subretinal bands. These patients present clinically with slowly progressive (regulated) detachments, that are often shallow and caused by atrophic holes. On OCT, the SR pattern presents with no significant outer retinal corrugations (ORCs) or cystoid edema. Instead, it is associated with retinal thinning, patchy or complete loss of the bacillary layer with hyperreflective subretinal membranes emanating from the RPE along the outer retinal surface. In some cases, outer retinal tractional folds and tractional bacillary layer detachment (BALAD) were observed. The second OCT phenotype of PVR is the intra-retinal/pre-retinal (IR/PR) subtype in eyes categorized clinically as having PVR C with fixed retinal folds. On examination, these patients present with rapidly progressive (dysregulated) extensive detachments that are usually bullous. On OCT, the IR/PR pattern shows high-amplitude ORCs with photoreceptor apposition, retinal thickening and associated pre-retinal membranes with loss of differentiation of the retinal lamellae and outpouching of the outer retina. In summary, this study showed that PVR does not manifest in a uniform manner across all detachments and cellular composition and factors driving proliferation seem to vary among different clinical contexts/RRD morphology. While the SR subtype had more atrophic changes in the retina, the IR/PR subtype of PVR reflects extensive structural remodeling. Her team believes that outer retinal apposition in the IR/PR subtype may represent an early sign of intraretinal gliosis and may occur more frequently in rapidly progressive (dysregulated) detachments.
