DR Medhat MRCP

Pituitary gland
Anatomy :
- Small oval gland (0.5 gm) at the base of the brain & lies within a bony fossa called “sella
turcica “ in the sphenoid bone at the base of the skull.
- The “diaphragm sellae” is a fold of dura mater which forms the roof of sella turcica &
separates the pituitary gland from the optic chiasma.
- The pituitary gland has 2 main parts , anterior (adenohypophysis) & posterior
(neurohypophysis)separated from each others by hypophyseal cleft. There is also a small
intermediate lobe.
- The pituitary gland is connected to hypothalamus via “pituitary stalk” which consists of :
1. Anterior part (hypothalamo-hypophyseal portal circulation) :
‣ Vascular connection () hypothalamus & anterior pituitary which brings
the anterior pituitary under the control of hypothalamic hormones.
2. Posterior part (infundibulum) :
‣ Neural connection () hypothalamus & posterior pituitary which
transfers the hormones synthesized by neuro-secretory neurons in
hypothalamus to be stored in posterior pituitary.
Blood supply of pituitary gland :
From hypophyseal arteries from circle of Willis