Spontaneous Improvement of Progressive Anterior Ischemic Optic Neuropathy-Reply

In reply  McHenry and Spoor suggest that the presence of optic nerve sheath fluid is of primary importance in predicting whether or not progressive AION is likely to improve following optic nerve sheath fenestration. On the basis of their results,¹ they propose that the appropriate randomized clinical trial should be limited to those patients with demonstrable fluid in the optic nerve sheath, as documented with ultrasonography.The basis for the ongoing National Eye Institute-funded Ischemic Optic Neuropathy Decompression Trial (IONDT) is that surgery may benefit both progressive and nonprogressive forms of AION. Although patients with progressive AION are eligible for the study, there will not be sufficient numbers of patients recruited to detect a difference in outcome between these patients and those with nonprogressive disease. To exclude patients whose AION is not progressive, who have no detectable optic nerve sheath fluid, or who have both would make a prospective,