Anterior Optic Neuropathies without Optic Disc Edema

Anterior optic neuropathies in which the optic discs appear normal include nutritional optic neuropathy, vitamin B12 or folate deficiencies, toxic optic neuropathy due to drugs and heavy metals, and hereditary optic neuropathy. When these conditions become chronic, optic atrophy can occur. Treatment of these diseases, which can cause dramatic vision loss, should be done quickly and permanent neuronal damage should be prevented as much as possible. Therefore, this group of diseases should always be kept in mind by clinicians in cases of unexplained visual loss.