Trauma of the Pituitary Region

Abstract

The frequency of pituitary hormone deficiency after head trauma has been debated for a long time. Nevertheless, today it has become accepted that traumatic brain injury (TBI) can generate gonadotropin and somatotropin deficiency. Diabetes insipidus is frequent in the early phase, but permanent diabetes insipidus is much rarer than anterior pituitary dysfunction. Diagnosis is confirmed by axial T1WI, which best demonstrates the absence of posterior pituitary bright spot (Fig. 61.1). Severity of TBI seems to be an important risk factor for developing post-traumatic hypopituitarism, and has also even been observed after mild trauma. Post-traumatic pituitary deficiency is more frequently observed in young adults, involved mainly in motor vehicle accidents, than in the elderly, who are more commonly involved in falls. Pathophysiology of post-traumatic pituitary deficiency includes pituitary or hypothalamus hemorrhage or necrosis, vascular damage to the long hypophyseal portal system, hypoxic insult, shearing axonal injury, or direct mechanical insult to the pituitary gland, the pituitary stalk, or the hypothalamus.