 Introduction/Background Neuroendocrine abnormalities encompass a range of centrally mediated hormonal imbalances and organ-specific pituitary abnormalities. Imaging is generally focused on the pituitary gland and parasellar region and typically follows endocrine evaluation [1-3]. Abnormalities of the pituitary are often an incidental finding on imaging performed for other indications, though these may be associated with occult endocrine dysfunction [4], and focused imaging is commonly requested in follow-up of these lesions. Extrinsic mass effect can result in dysregulation of pituitary hormone release as well as extra-pituitary dysfunction. The hypothalamic pituitary axis consists of two separate neuroendocrine organs: the anterior pituitary system and the posterior pituitary system. The hormones of the anterior pituitary are thyroid-stimulating hormone, adrenal corticotrophic hormone, prolactin, growth hormone, and the gonadotropins. These are secreted under the influence of hypothalamic trophic factors. The posterior pituitary gland consists of axonal terminations of neurons whose cell bodies are located in the hypothalamus. The principal hormones secreted by these cells are oxytocin and vasopressin or antidiuretic hormone. The hypothalamus also participates in complex mediation of food intake, temperature regulation, sleep and arousal, memory, thirst, and other autonomic functions. Special Imaging Considerations This guideline emphasizes the initial imaging for diagnosis. Additional studies may be ordered specifically for image-guided surgical navigation systems or intraoperative imaging platforms. It is recommended that ordering physicians consult with their radiologists as to protocols that can accomplish surgical guidance needs, to minimize patient recall or reimaging [7-10].
Neuroendocrine Imaging.  Introduction/Background Neuroendocrine abnormalities encompass a range of centrally mediated hormonal imbalances and organ-specific pituitary abnormalities. Imaging is generally focused on the pituitary gland and parasellar region and typically follows endocrine evaluation [1-3]. Abnormalities of the pituitary are often an incidental finding on imaging performed for other indications, though these may be associated with occult endocrine dysfunction [4], and focused imaging is commonly requested in follow-up of these lesions. Extrinsic mass effect can result in dysregulation of pituitary hormone release as well as extra-pituitary dysfunction. The hypothalamic pituitary axis consists of two separate neuroendocrine organs: the anterior pituitary system and the posterior pituitary system. The hormones of the anterior pituitary are thyroid-stimulating hormone, adrenal corticotrophic hormone, prolactin, growth hormone, and the gonadotropins. These are secreted under the influence of hypothalamic trophic factors. The posterior pituitary gland consists of axonal terminations of neurons whose cell bodies are located in the hypothalamus. The principal hormones secreted by these cells are oxytocin and vasopressin or antidiuretic hormone. The hypothalamus also participates in complex mediation of food intake, temperature regulation, sleep and arousal, memory, thirst, and other autonomic functions. Special Imaging Considerations This guideline emphasizes the initial imaging for diagnosis. Additional studies may be ordered specifically for image-guided surgical navigation systems or intraoperative imaging platforms. It is recommended that ordering physicians consult with their radiologists as to protocols that can accomplish surgical guidance needs, to minimize patient recall or reimaging [7-10].