AIM: To observe the choroidal thickness in nonarteritic anterior ischemic optic neuropathy(NAION)measured by enhanced depth imaging optical coherence tomography(EDI-OCT)and evaluate its clinical significance.

METHODS: Totally 30 patients diagnosed with NAION were studied and 60 individuals with normal fundus were set as control. Choroidal thickness was measured by EDI-OCT. Choroidal thickness of the affected eye and contralateral eye in patient group and right eye of the control group were evaluated and recorded.

RESULTS: Differences in age, gender and refractive status between NAION group and control were not significant(P>0.05). Choroidal thickness near fovea and optic disc in affected eye and contralateral eye in patient group was thinner compared to these of control group(P<0.01). No statistical differences were observed in the choroidal thickness between affected eye and contralateral eye(P>0.05).

CONCLUSION: In NAION patients, choroidal thickness of affected eyes and unaffected contralateral eyes were significantly thinner compared to these of control group. Diminish of the observed choroidal thickness in this study might be explained by small vessels occlusion in posterior ciliary artery, which would affect the blood supply of the choroid.