Longitudinal Progression of Horseshoe Retinal Tear-Associated Rhegmatogenous Retinal Detachment Without Clinically Evident Complete Posterior Vitreous Detachment: A Case Report.

Posterior vitreous detachment (PVD) is considered a key event in the pathogenesis of rhegmatogenous retinal detachment (RRD), and horseshoe retinal tears are generally associated with vitreoretinal traction during PVD evolution. We report the longitudinal progression of horseshoe retinal tear-associated RRD without clinically evident complete PVD. A 64-year-old nonmyopic man presented to a general ophthalmology clinic with floaters and preserved visual acuity. Retrospective review of baseline ultrawidefield (UWF) imaging demonstrated a horseshoe retinal tear with localized macula-on temporal RRD extending to within approximately 2.5 disc diameters of the fovea, which had not been recognized initially. Posterior-pole optical coherence tomography (OCT) showed posterior hyaloid attachment at the macula and optic nerve head, without clinically evident complete PVD. However, posterior-pole OCT could not exclude localized peripheral vitreous separation or focal vitreoretinal adhesion adjacent to the tear. Approximately 6 months later, the patient presented with acute visual deterioration, and the detachment had progressed to a bullous macula-off RRD arising from the same tear. PVD was induced during pars plana vitrectomy. This case documents longitudinal progression of localized horseshoe retinal tear-associated RRD without clinically evident complete PVD. Although the underlying mechanism remains inferential, the clinical course is compatible with focal peripheral traction occurring before complete PVD becomes clinically evident. In symptomatic patients, preserved central visual acuity, unremarkable posterior-pole findings, and absence of clinically evident complete PVD should not lower concern for peripheral vitreoretinal traction, retinal breaks, or RRD. Meticulous peripheral retinal examination and intentional review of the temporal retina on UWF imaging remain essential.