In 1923, one of us with Dunn1 reported an etiologic study of a series of various optic neuropathies. The patients reported in the former article had presented themselves at the clinic for visual disturbances, with no knowledge of the basic condition. There were eighty-six patients in this group, with various types of optic neuropathies. Of these eighty-six patients, thirty-five showed primary optic atrophy, twenty-four atrophy of the papillomacular bundles, thirteen secondary atrophy, five optic neuritis, four choked disk and five retrobulbar neuritis. Of these various conditions, 40 per cent were due to central nervous system syphilis, 12.7 per cent to disease of the posterior sinuses, 11.6 per cent to brain tumor, 5.8 per cent to multiple sclerosis, 11.6 per cent to toxic amblyopia, 3.5 per cent to various conditions, and in 13.8 per cent the actual cause of the optic neuropathy could not be determined.
Since the publication of