Pontine myelinolysis and delayed encephalopathy following the rapid correction of acute hyponatremia.

We describe a case of pontine myelinolysis associated with hyponatremia and hyperammonemia resulting from bladder irrigation during a transurethral prostatic resection. Following the procedure the patient exhibited seizurelike activity. He underwent rapid correction of the hyponatremia, he initially recovered but developed encephalopathy 19 days later. Magnetic resonance images showed symmetrical lesions in the white matter of the cerebellar peduncles. A relatively small pontine lesion was also noted. The patient later recovered. This case demonstrates that myelinolysis associated with rapid correction of hyponatremia may be greater in the cerebellar peduncles than in the central pons.