Abstract
Abstract: :
Purpose: To determine whether topical brimonidine tartrate would provide neuroprotection for patients with acute non-arteritic anterior ischemic optic neuropathy. Topical brimonidine tartrate has been reported to have a neuroprotective benefit for retinal ganglion cells following experimental elevation of intraocular pressure and optic nerve injury in the rat. These results were the basis of the recently aborted clinical trial of brimonidine purite for acute NAION in humans. Methods: We performed a retrospective review of patients with NAION who were evaluated within three weeks of the onset of visual loss and had follow up for at least 8 weeks. 14 of these patients (treated) received brimonidine within 14 days (mean 5.5) of the onset of visual loss. 5 patients were treated after one day of symptoms. The drops were taken QID in 11, TID in 1, and BID in 2 patients. There were 17 control patients (untreated) who were matched to the treated group for age, gender, cardiovascular risk factors, prior aspirin use, and prior first eye NAION. The affected eye visual acuity was expressed as a decimal equivalent. The visual field defects were graded using a previously published scale (0 normal - 4 light perception). Results: The mean baseline acuity (0.56, sd 0.30) and visual field (1.9, sd 0.73) for the treated group was similar to the acuity (0.40, 0.41; p=0.22) and field (1.9, sd 0.75; p=0.96) for controls. At the 8 to 12 week examination, the mean visual acuity was 0.29 (sd 0.30) for treated and 0.49 (sd 0.39; p=0.12) for untreated patients. The mean visual field grade was 2.2 (sd 0.81) for treated and 1.62 (sd 0.70; p=0.04) for untreated patients. There was no correlation with a worse outcome and delay in initiating therapy and the average time to start the drops was 3.5 days in those who worsened. Conclusion: Topical brimonidine tartrate, given for NAION after one day, does not appear to offer a neuroprotection for this disorder.
Keywords: 487 neuro-ophthalmology: optic nerve • 489 neuroprotection