Traumatic optic neuropathy is a severe complication of craniofacial trauma, often missed at emergency room in patients with low Glasgow coma scale (GCS). Diagnosis is established by analyzing pupillary responses to light in patients with low GCS. A significant number of head injuries present with primary or secondary injuries in and around the globe of the eye. Traumatic optic neuropathy (TON) may involve optic nerve, chiasma, tracts or radiation, or cortical centers. They are discussed in this chapter.