Relationship between progression of visual field damage and choroidal thickness in eyes with normal‐tension glaucoma

A bstract Background: To measure choroidal thickness in normal eyes and in patients with normal‐tension glaucoma using enhanced depth imaging optical coherence tomography and evaluate the association between choroidal thickness and progression of visual field damage. Design: Cross‐sectional comparative study. Participants: A total of 62 eyes of 62 normal subjects and 45 eyes of 45 normal‐tension glaucoma patients were examined. Methods: The choroid was measured at the fovea and 3 mm nasal and temporal from the fovea. In the separate study, both eyes of the patients with normal‐tension glaucoma were included in the analyses. Visual fields were measured with automated perimetry. Changes in mean deviation per year (dB/year), that is, mean deviation slope, were calculated. Main Outcome Measures: Difference in the choroidal thickness between the normal subjects and the patients with normal‐tension glaucoma. The relationship between mean deviation slope and the choroidal thickness in eyes with normal‐tension glaucoma was analysed. Results: Compared with normal subjects, the choroidal thickness was significantly thinner in eyes with normal‐tension glaucoma at 3 mm nasal from the fovea ( P = 0.02). There was a significant correlation between the choroidal thickness at 3 mm nasal from the fovea and the mean deviation slope (Pearson's r = 0.413; P < 0.001). Conclusion: The decrease in the thickness of the choroid at 3 mm nasal from the fovea in eyes with normal‐tension glaucoma may be associated with progressive visual field loss. Thus, choroidal abnormalities may play a role in the pathogenesis of normal‐tension glaucoma.