Grand Rounds

A patient with longstanding hypertension presented with a spontaneous macular hemorrhage and visual acuity of count fingers. Dense preretinal and intraretinal hemorrhage was identified on fundus examination, with fluorescein angiography and indocyanine green angiography confirming the diagnosis of retinal arterial macroaneurysm rupture. Two intravitreal bevacizumab injections were administered, and the hemorrhage resolved over subsequent months. Seven months after the initial event, a thick epiretinal membrane was identified on optical coherence tomography as hemorrhage cleared. Over the following years, the membrane matured into a hyperreflective, hypercellular structure with progressive vitreomacular traction. A distinctive hyperreflective signal at the vitreoretinal junction was noted — a finding pathognomonic of retained hyalocyte-rich vitreous cortex following anterior vitreoschisis. Despite membrane thickness and traction, visual acuity remained stable at 20/30 over 7.5 years of observation, attributable to preserved foveal architecture. The fellow eye subsequently developed a separate epiretinal membrane, reflecting bilateral manifestations of chronic hypertensive vascular disease. This case explores the mechanism by which a single vascular event triggers a cascade of anomalous posterior vitreous detachment, hyalocyte activation, myofibroblast transdifferentiation, and organized membrane formation. The roles of TGF-β2, PDGF, VEGF, and the ROCK pathway in membrane pathogenesis are reviewed, with emphasis on how secondary epiretinal membranes differ fundamentally from idiopathic ones in cellular composition, thickness, and natural history. Criteria for observation versus surgical intervention are discussed.

Presentation Date: 02/19/2026
Issue Date: 04/03/2026