Peripapillary choroidal thickness in nonarteritic anterior ischemic optic neuropathy.

PURPOSE: To compare peripapillary choroidal thickness, macular thickness, and peripapillary retinal nerve fiber layer (RNFL) thickness between the affected eyes of patients with nonarteritic anterior ischemic optic neuropathy (NAION) and their unaffected eyes and the eyes of normal control subjects.

METHODS: Thirty-two eyes with NAION, 25 unaffected fellow eyes, and 25 normal control subjects met the inclusion criteria in this prospective comparative study at a single academic institution. Optic disc area, macular thickness, and RNFL thickness were evaluated at last follow up time using spectral-domain optical coherence tomography (OCT). Enhanced depth imaging OCT was obtained to evaluate peripapillary choroidal thickness.

RESULTS: Mean follow up time was 4.9 ±0.8 months and all data was collected from the last follow up. The mean optic disc area in NAION eyes and their unaffected fellow eyes were significantly smaller than normal control disc area measurements (P<0.001). Average PCT and all regional values were significantly greater in the NAION eyes and unaffected fellow eyes than in the control eyes (P=0.01). In all subjects, optic disc area was correlated with average PCT (r = -0.33, P = 0.002). In addition, RNFL thickness and macular thickness values were significantly lesser in the NAION eyes than in the unaffected fellow eyes and control eyes.

CONCLUSIONS: PCT is thicker in NAION eyes and unaffected fellow eyes than control eyes. Thick peripapillary choroid might contribute to the development of NAION.