Pituitary imaging abnormalities in patients with and without hypopituitarism after traumatic brain injury

Recent evidence suggests that patients with traumatic brain injury (TBI) are at substantial risk of hypopituitarism. The pathomechanisms, however, are not completely understood yet. Little is known about the association of morphological changes in the sella region with pituitary function in TBI. In this study, we assessed morphological abnormalities of the sella region in patients with TBI and their relation to endocrine function. We studied magnetic resonance (MR) or computed tomography (CT) scans of 22 patients with TBI [17 men, 5 women, age (mean+/-SD) 43.5+/-10.6 yr, time after trauma 17.4 +/-15.0 yr]. Of these, 15 patients had some degree of hypopituitarism. We found abnormalities of the sella region in 80% of the patients with hypopituitarism and 29% of those without hypopituitarism (Fisher's exact test, p=0.032). The most common abnormality was loss of volume or empty sella, followed by native signal inhomogeneities, perfusion deficit, and lack of neurohypophyseal signal. Our results indicate that pituitary imaging abnormalities are more common in TBI patients with hypopituitarism than those without. Both immediate trauma-induced pathology as necrosis and hemorrhage as well as multifactorial mid- to long-term changes may underlie these abnormalities.