RETROBULBAR neuritis is a common disorder which may be the initial manifestation of one of several disease processes. It is characterized by a loss of vision following a lesion of the optic nerve; usually no changes are found on ophthalmoscopy. The purpose of this paper is to present the results of a follow-up examination of patients who appeared with an acute unilateral retrobulbar neuritis and who had no other symptom or sign indicative of any specific disease process at that time. These patients are unlike the majority of patients who have had a retrobulbar neuritis, for usually some other symptom or sign indicative of a primary disorder accompanies the condition. In this regard, these cases always are a uniquely difficult diagnostic problem.
An attempt has been made to determine what, if any, disease subsequently developed in these patients. As retrobulbar neuritis is often an early solitary manifestation of multiple