Hypophysitis Research Center

Resources

Glossary of Terms and Definitions

Autoimmune Hypophysitis
Response of the immune system against the hypophysis. It is also called Lymphocytic Hypophysitis because lymphocytes are the main cells infiltrating the hypophysis. It has been increasingly recognized in the last 20 years, due to a better understanding of its clinical, radiological and pathological features of the disease.
Autoimmunity
Response of the immune system against components (antigens) of the host itself (rather than against invading parasites, bacteria or viruses). This autoimmune attack is mediated by antibodies or hematopoietic cells (usually lymphocytes).
Bitemporal Hemianopsia
A type of visual defect characterized by loss of vision in the lateral (temporal) half of the two visual fields. Typically caused by an enlarged hypophysis, which compresses the optic chiasma.
Choroid Plexus
A network of capillaries located in the walls of the four brain ventricles. These plexuses are the production sites of the cerebrospinal fluid, a colorless liquid that protects the brain and the spinal cord against chemical and physical injuries.
Endocrine
Endocrine refers to the fact that a gland secretes its products into the bloodstream. Other glands instead, such as the lacrimal glands, secrete their products outside the body (exocrine). For example, the lacrimal glands secrete tears and are therefore exocrine glands.
Hormone
Substance produced by an endocrine gland and transported in the bloodstream to a target tissue, where it carries on its function (stimulatory or inhibitory).
Hyperplasia
An increase in the size of an organ or a tissue as a result of increased numbers of cells.
Hypertrophy
An increase in the size of an organ or a tissue as a result of increased size of the individual cells.
Hypophysitis
Inflammation of the hypophysis, which be an acute or chronic.
Hypopituitarism
Clinical condition characterized by a deficiency of one or more of the hormones produced by the hypophysis. Autoimmune hypophysitis can result in hypopituitarism.
Hypothalamus
Part of the brain located above the pituitary, to which it is anatomically connected. It contains specialized nervous cells which regulate the production and release of pituitary hormones.
Optic Chiasma
Part of the visual tract where the fibers of the left and right optic nerve meet and partially cross. The chiasma is located in front of and above the hypophysis, so it may be compressed when the hypophysis is enlarged.
Sella Turcica
A deep depression of the sphenoid bone, at the base of the skull, which surrounds the hypophysis.
Visual Field Defect
A loss of vision in a particular area of the visual field. Bitemporal hemianopsia is an example of visual field defect.