Delayed substantia nigra damage and leukoencephalopathy after hypoxic-ischemic injury.

Delayed post-anoxic encephalopathy has rarely been reported, and has most commonly been associated with carbon monoxide poisoning. The underlying pathophysiological mechanism is unknown. We describe a patient with a delayed neurologic decline after a good initial recovery from a hypoxic-ischemic event precipitated by acute blood loss. MRI revealed early globus pallidus necrosis followed by delayed substantia nigra damage and leukoencephalopathy. We suggest that anemia might play a role in this pattern of hypoxic-ischemic brain injury.