Foveal choroidal thickness assessment with SD-OCT in high myopic glaucoma

Objective: To measure macular choroidal thickness (CT) using spectral domain optical coherence tomography (OCT) in high myopic eyes with primary angle-open glaucoma (POAG), and to investigate whether the choroid is thinner in these eyes compared to high myopic eyes without glaucoma.

Methods: We conducted a cross-sectional study of forty-eight eyes with high myopic glaucoma matched with 48 highly myopic eyes without glaucoma by age, central corneal thickness and axial length (AL). OCT scans were performed with the spectral domain OCT (Topcon 2000). The subfoveal CT was measured between the Bruch membrane and the internal aspect of the sclera.

Results: In the subgroup without glaucoma, matched with the subgroup with glaucoma (P=0.57), by age, central corneal thickness (P=0.33) and AL (P=0.10), the mean subfoveal CT was 96.32 μm ± 39.56 μm. In the subgroup with glaucoma, the mean subfoveal CT was 50.44 μm ± 16.36 μm. The comparison between the two subgroups found a statistically significant difference in subfoveal CT (P<10(-4)).

Conclusions: Foveal choroidal thickness is reduced in highly myopic eyes with glaucoma. The choroidal thinning can be a useful parameter for the diagnosis and the follow-up of highly myopic patients with glaucoma.