A case of central pontine myelinolysis after surgical removal of a pituitary tumor

Abstract

We have experienced a case in which surgical removal of a pituitary tumor from a male patient was followed by the occurrence of hyponatremia, which in turn was later associated with central pontine myelinolysis (CPM). A 4 X 3 X 3 cm pituitary tumor with hypothalamic extension was removed via a transsphenoidal approach. The post-operative course was uneventful until severe hyponatremia developed. To avoid drastic correction of electrolyte levels, reestablishment of normal serum levels was spread over 1 week. Following this, however, various neurologic symptoms such as pseudobulbar palsy, quadriplegia, extrapyramidal symptoms, and mental symptoms appeared. The case was diagnosed as CPM and extrapontine myelinolysis (EPM) on the basis of the clinical course and symptoms, and high-dosage steroid therapy was commenced. There was consequent gradual improvement in symptoms. One month later, MRI revealed typical demyelination lesions in the central pons and striatum. Abnormal electrolyte conditions easily occur in pituitary tumors associated with hypothalamic extension in an altered hormone environment. It is known that CPM and EPM result from drastic correction of hyponatremia. The frequent measurement of electrolytes and cautious correction of sodium imbalance are important for the prevention of CPM and EPM in the postoperative management of patients who undergo surgery for a pituitary tumor and whose high-dosage steroid therapy are effective.