Persistent hypophyseal (craniopharyngeal) canal.

Two cases with a broad persistent hypophyseal canal connecting pituitary fossa and nasopharynx are presented. Both had nasopharyngeal surgery in early childhood and presented later with hypopituitarism. Coronal CT demonstrated the defects with no visible pituitary tissue. The spectrum of basal skull defects is discussed. Children with midline nasal polyps should have CT or MRI of the skull base prior to surgery to prevent inadvertent hypophysectomy.