Pontine neoplasm or myelinolysis despite normal sodium levels.

An elderly woman was transferred for biopsy of a pontine lesion. Her condition, including gait disturbances, truncal ataxia, and dysarthria - presumed to be due to a history of severe alcohol abuse - deteriorated over the course of treatment for ambulatory-acquired pneumonia. No electrolyte abnormalities were noted during hospitalization. However, neuroimaging was in line with central pontine myelinolysis, typically sparing the peripheral pontine fibers. Although extremely rare, pontine myelinolysis can occur in the presence of normal electrolytes. Thus, images should not be misinterpreted as pontine neoplasms and patients should not undergo stereotactic biopsy - a procedure that may harbor disastrous morbidity.