The pituitary gland is a gland which is suspended and attached to the brain.
It is often described as the conductor of an orchestra, as it regulates many hormonal systems.
The pituitary produces hormones which regulate growth, sexual development and reproduction, breast feeding, thyroid hormone production and steroid production.
For many women abnormalities of the functioning of the pituitary come to light during investigations associated with menstrual irregularities or unexpected breast milk production.
For men abnormalities can come to light during investigations performed to discover the potential cause for a lack of libido or weak bones.
Quite often abnormalities are found when head scans are performed to investigate other problems, such as headaches, and a swelling of the pituitary is noted.
Cushing's Disease is a condition where the body produces too much adrenal steroid hormone as a consequence of stimulation from the pituitary gland.
Unfortunately it is not always simple to tell whether an abnormality is a consequence of a pituitary problem or another cause.
To investigate problems with the pituitary an MRI scan is often performed, but occasionally a CT scan may suffice is there are contraindications for an MRI.
Blood tests are needed and these may be 'baseline' or 'dynamic'.
A baseline test may be performed at different times of the day. Dynamic tests require the administration of hormones to assess the response of the pituitary to those hormones.
A more detailed explanation of the functioning of the pituitary may be found on the following websites:
The Pituitary Foundation
The Society for Endocrinology - Patient Information