Background: To compare the macular and peripapillary choroidal thickness between normal and glaucoma eyes and find out factors related to choroidal thickness using enhanced depth imaging (EDI) of Heidelberg Spectralis SD-OCT.

Methods: Cross-sectional transverse study. Methods: A total of 108 glaucoma patients and 48 healthy controls were included in the analysis. Choroidal thickness was measured from 6 mm length radial B-scans at the macular and the optic nerve head by EDI OCT. Choroidal thickness was compared between normal controls, normal tension glaucoma (NTG) patients, and primary open-angle glaucoma (POAG) patients. Factors related to choroidal thickness were analyzed by regression analysis.

Results: There were no differences in average, temporal, nasal, superior, and inferior macular choroidal thickness between normal, NTG, and POAG eyes. The peripapillary thickness did not differ between normal and POAG eyes; however, average, temporal, nasal, superior, and inferior peripapillary choroidal thickness were significantly thinner in NTG eyes. Axial length (β=-11.36, P<0.001) was the most significant factor associated with peripapillary choroidal thickness, followed by age (β=-5.10, P<0.001). Glaucoma type (β=-11.28, P<0.001) were also significantly associated with peripapillary choroidal thickness.

Conclusions: Peripapillary choroidal thickness was significantly reduced in NTG eyes based on EDI OCT measurements in vivo.