Posttraumatic hypopituitarism is the failure of the hypothalamic-pituitary axis secondary to traumatic brain injury. It can clinically present as decreased muscle mass, concentration, libido, and fertility. It can also present as increased fatigue, depression, and cognitive deficits. In addition, electrolyte abnormalities such as hyponatremia can occur in hypopituitarism. As a result of heightened awareness of posttraumatic hypopituitarism, it is a phenomenon that is becoming more commonly diagnosed. Posttraumatic hypopituitarism is a diagnosis based on clinical evaluation, laboratory testing, and neuroimaging. Of the radiological techniques, magnetic resonance imaging is the preferred technique to image the pituitary gland. This article contains coronal and sagittal magnetic resonance imaging of the posterior fossa, illustrating the normal hypothalamus and pituitary gland as well as adjacent structures. The sequential enhancement pattern of the normal pituitary gland is consistent with its vascular supply. A colored illustration was created to display the vascular supply to the hypothalamus, pituitary stalk, and pituitary gland.
From the *Department of Physical Medicine and Rehabilitation, Baylor College of Medicine; †Center for Trauma Rehabilitation Research, Quentin Mease Hospital, Harris County Hospital District; ‡VISN 6 Mental Illness Research, Education, and Clinical Center; §Mental Health and Behavioral Sciences Service Line, W.G. (Bill) Hefner Veterans Affairs Medical Center, Salisbury, NC; and ∥Division of Biomedical Sciences, Virginia College of Osteopathic Medicine, Blacksburg, VA.
Received for publication November 27, 2007; accepted November 27, 2007.
Reprints: Faye Y. Chiou-Tan, MD, Department of Physical Medicine and Rehabilitation, Quentin Mease Hospital, 3601 N. MacGregor, Suite No. 240, Houston, TX 77004 (e-mail: email@example.com).