Ischemic Optic Neuropathy Decompression Trial: An Update

As recently as 1989 ophthalmologists had no treatment for non-arteritic anterior ischemic optic neuropathy (NAION). Primarily affecting the elderly, NAION can devastate vision since it affects both eyes in 40% of afilicted patients and leads to visual acuity of 20/200 or worse in 45% of affected eyes.1 Although most neuro-ophthalmologists believe that the likelihood of spontaneous improvement is low, published reports show a wide range of spontaneous visual improvement in cases of NAION, varying between 5% and 33%. Unfortunately, most published reports describing the natural history of NAION are based on medical records reviews and did not use standardized methods of data measurement or collection. In addition, most reports are based on small numbers of patients who were followed up for varying lengths of time. Until prospectively collected data on untreated patients become available, information regarding the natural history ofNAION must be interpreted cautiously.