Pituitary Apoplexy
Patients with pituitary apoplexy present with severe headache of acute onset, which is typically considered as the worst headache ever experienced. Nausea and vomiting are very common. The rapid expansion…
Postpartum Pituitary Infarction (Sheehan Syndrome)
To understand the development of postpartum pituitary infarction, one has to consider that the pituitary gland becomes hyperplastic (approximately doubling in mass) during pregnancy as a result of progressive lactotroph…
Anterior Pituitary Hormone Deficiencies
A wide variety of conditions may cause dysfunction of the hypothalamus or pituitary, leading to selective or universal, partial or complete, acute or chronic loss of adenohypophyseal hormone secretion (anterior…
Severe Anterior Pituitary Hormone Deficiencies (Panhypopituitarism)
Pituitary macroadenomas, which, by definition, exceed 10 mm in greatest diameter, may cause multiple anterior pituitary hormone deficiencies but only rarely cause diabetes insipidus preoperatively. In contrast, large suprasellar tumors…
Effects of Pituitary Mass Lesions on the Visual Apparatus
A variety of mass lesions may arise within the sella. In addition to benign pituitary adenomas, which account for approximately 90% of mass lesions in surgical series, there are a…
Posterior Pituitary Gland
Oxytocin and antidiuretic hormone (vasopressin) are made by distinct populations of large (magnocellular) neurons in both the paraventricular (PVN) and supraoptic (SON) nuclei, which release the hormones from their axons…
Anatomic Relationships of the Pituitary Gland
The optic chiasm rests superiorly to the diaphragma sellae. Nerve fibers originating in the nasal portion of each retina cross at the chiasm to the contralateral side and join ipsilateral…
Divisions of the Pituitary Gland and Its Relationships to the Hypothalamus
The gland is composed of the adenohypophysis and the neurohypophysis, which are embryologically, anatomically, and functionally distinct. The former derives from the Rathke’s pouch, an ectodermal outgrowth of the primordial…
Sleep-Disordered Breathing
Clinical Presentation. Pronounced snoring, a classic indicator for possible sleep apnea is related to vibration of upper airway tissue. Apnea occurs when the upper airway obstruction becomes complete. There is…
Narcolepsy: A Hypothalamic Sleep Disorder
The cause of narcolepsy was quite mysterious until a new neurotransmitter, orexin (also called hypocretin) was discovered in 1998. The orexin neurons are found in the lateral hypothalamic area. They…
