Objective: To establish the natural history of a series of impending macular holes presenting as foveal pseudocysts using optical coherence tomography (OCT).
Design: In a prospective observational case series, patients exhibiting a foveal pseudocyst on biomicroscopy were examined with OCT and were followed up for 3 to 26 months (mean, 9.4 months)
Participants: Twenty-two eyes of 20 consecutive patients examined for a macular hole in the fellow eye or reporting visual symptoms in only one eye, in whom a foveal pseudocyst was diagnosed on OCT.
Methods: In all cases, fundus biomicroscopy and OCT findings were compared.
Main outcome measures: Biomicroscopic fundoscopy, OCT scans, and visual acuity.
Results: Eight foveal pseudocysts occurred in the fellow eye of an eye with a macular hole, and 14 were diagnosed in patients with unilateral visual symptoms. In four of the 22 eyes, the macula was considered normal on biomicroscopy. In the 18 others, biomicroscopy detected a foveal pseudocyst, radial striae, a yellow spot or ring, or a combination of these findings. No posterior vitreous detachment was seen on biomicroscopy in any of the eyes. On OCT, the cystoid space occupied the inner part of the foveal tissue in the stage 1A impending hole; a stage 1B impending hole corresponded to a cystoid space that extended posteriorly, disrupting the outer retinal layer. During the follow-up period, three pseudocysts evolved into full-thickness macular holes, four turned into lamellar holes, seven resolved completely after detachment of the posterior hyaloid, and eight remained unchanged for a long time.
Conclusions: Foveal pseudocysts are a specific entity occurring either as a primary ocular involvement or in the fellow eye of an eye with a macular hole. Foveal pseudocysts are the first step of full thickness macular hole formation, but they also may evolve into a lamellar hole, may persist unchanged for months, or may resolve completely. Foveal pseudocyst formation may be the result of the incomplete separation of the vitreous cortex at the foveal center and the particular structure of the foveal Müller cells.