Optical coherence tomography en face analysis of the posterior vitreous reveal topographic relationships between premacular bursa, prevascular fissures and cisterns

Abstract Purpose To characterize the topographic relationships among vitreous structures including the premacular bursa, prevascular vitreous fissures, cisterns and lacunae in healthy subjects using en face and cross-sectional swept-source optical coherence tomography (SS-OCT). Design Prospective comparative study. Subjects Sixty eyes of 60 healthy subjects (age range = 4 – 35 years). Eyes of individuals younger than 20 years (n= 29) were compared with eyes of individuals aged 20 years or older (n=31). Testing Twelve x 12-mm SS-OCT volume scans comprised of 1024 x 1024 A-scans centered at the fovea were acquired from each study eye. Main Outcome Measures En face and cross-sectional data was analyzed to characterize topographic relationships between hyperreflective spaces anterior to the vitreoretinal interface. Results Prevascular vitreous fissures are an almost universal feature of human eyes. Cisterns became more prevalent over the course of the first 20 years (r=0.49, P=0.002). In 97% of eyes in individuals older than 20, en face and cross-sectional SS-OCT showed the premacular bursa and prepapillary gap merge at a distance superior to the optic nerve and then follow a superonasal course anteriorly. However, only 69% of individuals younger than 20 years demonstrated such a connection (p= 0.01). A close topographical relationship of vitreous fissures and cisterns to the underlying vasculature of the posterior pole was visible on en face projections. En face imaging readily distinguishes these spaces. Degenerative, eyewall-parallel fissure planes and their course are described for the first time in a three-dimensional manner. The fissure planes were rare in younger eyes (12%), and significantly more common in older eyes (42%; p Conclusions En-face SS-OCT demonstrates (1) that premacular bursa and Cloquet’s canal are not connected in younger, but in older patients, that (2) prevascular vitreous fissures overly the retinal vessels, and (3) that cisterns are continuous with PVFs.