Neuroendocrine disorders: pituitary imaging.

Significant advances in pituitary imaging have taken place in the past several decades, including the introduction of magnetic resonance imaging (MRI). This imaging modality has vastly improved our ability to detect and characterize sellar masses and more accurately characterize the extent and spread of lesions in and around the sella. Intraoperative MRI may help improve the completeness of resection of sellar masses. Other imaging modalities, including magnetic resonance angiography, computed tomography (CT), and CT angiography, have an important role in specific cases. Interventional methods, including bilateral inferior petrosal sinus sampling, may establish the pituitary origin of corticotropin (ACTH) excess in patients with ACTH-dependent Cushing's syndrome. Pituitary imaging should be obtained in patients with pituitary hormone excess, hypopituitarism, or mass effect in the sella. Despite rapid advances in pituitary imaging, there are several diagnostic challenges remaining. Future research may help improve the radiographic detection of small sellar lesions, such as ACTH-secreting adenomas causing Cushing's disease, accurately characterize the type and extent of sellar pathologies, and provide prognostic information regarding their growth potential.