Effects of steroid administration and transcorneal electrical stimulation on the anatomic and electrophysiologic deterioration of nonarteritic ischemic optic neuropathy in a rodent model.

PURPOSE: To elucidate the effectiveness of steroid administration and transcorneal electrical stimulation (TES) on anatomic changes and visual function in a rodent model of nonarteritic ischemic optic neuropathy (rNAION).

METHODS: Methylprednisolone (20 mg/kg) was injected through a central venous catheter twice a day for 3 days. TES was delivered with biphasic square pulses of 1 ms/phase, 100 μA of current, and 20 Hz of frequency for 60 min 3 h after induction on the 1st, 4th, 7th, 14th, and 28th days.

RESULTS: Intravenous infusion of methylprednisolone significantly decreased the degree of acute disc edema but did not preserve the inner retinal thinning, decreasing the amplitude of scotopic threshold responses (STR) and decreasing retinal ganglion cell (RGC) numbers in rNAION. TES preserved the decreasing STR amplitude and the decreasing RGC numbers in rNAION.

CONCLUSION: Steroids are effective for reducing disc edema in the acute stage in rNAION. TES is effective for preserving decreasing RGC numbers and function in the chronic stage of rNAION.