A 47-year-old alcoholic man with progressive abnormal gait.

Central pontine myelinolysis should be considered in the differential diagnosis of a patient with a history of alcoholism and malnutrition presenting with ataxia, regardless of serum sodium values. T2-weighted images are the most sensitive imaging technique, but changes may not be evident for weeks after the insult, and in addition, the insult may not be known. Supportive care is important to prevent complications, but no treatment has been found to be effective in treating the illness. Patient outcomes vary considerably and are difficult to predict.