The first symptom of traumatic optic neuropathy is mostly sudden vision loss, and in severe cases, blindness. In addition, optic disc edema and peripheral retinal hemorrhage, occlusion of vision (i.e. visual field defect), color vision abnormalities, pupil dilatation in the injured eye and abnormal reaction to light may also occur after optic nerve injury. Most intracranial optic nerve injuries are caused by skull base fractures, which may be accompanied by traumatic subarachnoid hemorrhage, mild paroxysmal headache, or severe sudden coma with symptoms of meningeal irritation (neck stiffness, etc.).