Definition of Craniopharyngioma
Craniopharyngioma: A benign brain tumor that develops from embryonic tissue that forms part of the pituitary gland. Pressure on the pituitary gland by the tumor reduces the availability of the hormone vasopressin, raising the pressure within the cranium. A craniopharyngioma usually includes hard, calcified components within the tumor itself and affects the development of the adjacent skull. Treatment is usually surgery.