Revisiting Pituitary Apoplexy

Abstract

Pituitary apoplexy (PA) is a rare clinical syndrome due to pituitary hemorrhage or infarction. It is characterized by the sudden onset of one or more of the following: severe headache, visual disturbance, nausea/vomiting, and or altered mental status. Most commonly, PA occurs in an underlying pituitary adenoma. The pathophysiology is not fully understood, but it is thought to involve elements of increased metabolic demand and/or compromise to the vasculature of the pituitary or pituitary tumor. Several risk factors have been described. Stabilization of the patient on presentation, replacement of hormonal deficiencies, and reversal of electrolyte abnormalities are the recommended initial steps in the management of patients with PA. Surgical decompression of the mass effect had been the recommended treatment for patients with PA; however, retrospective studies of patients with PA have demonstrated similar outcomes when a conservative approach is applied. This suggests that in highly selected clinical scenarios (mild visual deficit and improving symptoms), conservative management is possible. Further studies, however, are necessary to better stratify patients but are limited by the rarity of the condition and the acuity.

Keywords: hypopituitarism; pituitary apoplexy; pituitary hemorrhage; pituitary infarction; pituitary necrosis; pituitary tumor.

Figure 1.

Pituitary apoplexy following head trauma in a 61-year-old cyclist on aspirin who developed acute loss of vision in the left eye. A, Noncontrast axial computed tomography (CT) image demonstrating left temporal bone fracture with associated subdural hematoma (white arrow). The sella is expanded because of the presence of a pituitary adenoma. Within the center of pituitary adenoma there is hyperintense material as a result of hemorrhage (black arrow). B, T2 axial magnetic resonance imaging (MRI); C, T1 axial MRI; and D, T1 sagittal MRI performed shortly afterward also demonstrate the pituitary tumor and hemorrhage, extending suprasellar and leading to visual symptoms. In the acute phase hemorrhage is hypointense on T1 and can therefore be difficult to visualize compared to CT.

Figure 2.

Hemorrhagic pituitary apoplexy within a pituitary adenoma demonstrating a fluid-fluid level seen on A, sagittal T1 and B, axial T2 imaging 1 month after initial event. The upper layer of fluid is hyperintense on T1 containing extracellular met hemoglobin whereas the lower layer contains blood remnants.