En face imaging of posterior precortical vitreous pockets using swept-source optical coherence tomography

To obtain sequential flat (en face) images of posterior precortical vitreous pockets (PPVPs) using swept-source optical coherence tomography (SS-OCT).

We performed SS-OCT in the right eyes of 112 volunteers (mean age, 30.1 years; mean refraction, -2.5 diopters) while sitting using 12-mm horizontal, vertical scans of the 12- × 9-mm plane × 2.6-mm depth through the macula and optic disc. En face images of the posterior vitreous were obtained by En-View, a SS-OCT program.

Swept-source OCT visualized the PPVPs and Cloquet's canals in all subjects; the PPVPs appeared as boat-shaped lacunae in the horizontal scan and extended superiorly as clefts in the vertical scan. En face imaging showed PPVPs and Cloquet's canals as two oval lacunae near the vitreoretinal interface and a septum between the nasal border of the PPVPs and Cloquet's canals. In all cases, the lacunas of the PPVPs were larger than those of Cloquet's canals. In 99 (88.4%) of 112 eyes, the PPVPs and Cloquet's canals were fused by connecting channels. The mean width of the connecting channels was 920.2 ± 37.4 μm, and the mean height was 288.6 ± 20.0 μm. On the anterior en face images, the PPVPs became crescent-shaped in all eyes.

Using SS-OCT, we obtained en face images of PPVPs and Cloquet's canals in vivo. The en face images of the PPVPs near the retina showed oval shapes that changed to crescents, which corresponded to the superior edge of the PPVPs. The PPVPs were fused with Cloquet's canal by a flat-shaped connecting channel.