Radiographic pituitary stalk disruption: A rare sequela of secondary empty sella syndrome

BACKGROUND: This two-patient case series describes a rare sequela of postoperative empty sella syndrome (ESS) following transsphenoidal resection of pituitary macroadenomas. This is characterized by progressive hormone dysfunction, diabetes insipidus (DI), and associated MRI evidence of pituitary stalk disruption. CASE DESCRIPTION: This phenomenon was retrospectively evaluated in a review of 2000 pituitary tumor resections performed by a single neurosurgeon (KOL). Chart review was retrospectively conducted to gather data on demographics, pituitary hormone status, tumor characteristics, and management. We identified 2 (0.1%) cases of progressive pituitary endocrine dysfunction occurring in the postoperative period associated with MRI evidence of pituitary stalk disruption within 6 weeks of discharge from the hospital. This was felt to be caused by the rapid descent of the residual normal pituitary gland down to the floor of the postoperative empty sella, causing relatively swift stalk stretching. Both patients developed DI, and one patient demonstrated increased pituitary hormone dysfunction. CONCLUSION: This phenomenon is a rare manifestation of postoperative ESS, secondary to surgical resection of a pituitary macroadenoma. We discuss the associated potential risk factors and strategies for avoidance in these two cases. Routine instillation of intrasellar fat in patients at risk is felt to be protective.