TABLE 30.5 CAUSES OF CORTICAL BLINDNESS Cardiac arrest Status epilepticus Hypoxia Perinatal asphyxia Cerebral infarction Meningitis Encephalitis Subacute sclerosing leukoencephalitis Hypoglycemia Uremia Hydrocephalus Shunt malfunction Head trauma Cardiac surgery Posterior reversible encephalopathy syndrome Cerebral or vertebral angiography Drugs (steroids) Carbon monoxide poisoning Occipital epilepsy Postictal states Hypertensive crisis Visual impairment may also result from interference with the visual cortex of the brain Cortical blindness has many causes ( Table 30.5 ) Head trauma (see Chapters 41 Injury: Head and 113 Neurotrauma ) may cause total loss of vision soon after the injury This has been called “footballer’s migraine” because of its association with head trauma in soccer Even trivial head trauma has been known to cause blindness The physical examination may be completely normal There may be a delay of onset, but the entire course is usually brief, lasting minutes to hours This form of blindness is often confused with hysterical blindness, the