Pituitary Glossary starting with M

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Magnetic Resonance Imaging (MRI)

MRI is a scanning device that uses a magnetic field, radio waves, and a computer.

Signals emitted by normal and diseased tissue during the scan are assembled into an image


In reference to an abnormal tissue growth neoplasm (cancer), having the property of locally invasive and destructive growth and metastasis (spreading).

Semantics prevail. For example, invasive pituitary tumors are not thought to be malignant.


Imaging examination of the breast by means of x-rays

Used for screening and diagnosis of breast disease. Ultrasound and magnetic resonance may also be used to image the breast.

Mass Effect

Damage to the brain due to the bulk of a tumor, the blockage of fluid, or excess accumulation of fluid within the skull.

Damage to the brain due to the bulk of a tumor, the blockage of fluid, or excess accumulation of fluid within the skull.


The word medial comes from the Latin medialis, from medius, meaning the middle. Medial is the adjective corresponding to the noun median, as in the median in a highway.

Pertaining to the middle; in or toward the middle; nearer the middle of the body. Medial is as opposed to lateral. For example, the medial side of the knee is the side closest to the other knee whereas the lateral side of the knee is the outside of the knee.

Within a multilayered structure, the center layer. The medial layer of the aorta is the middle layer. For example, necrosis of the medial layer of the aorta may lead to aortic rupture.

Median Survival

Median means the middle value.

An equal number of people live longer as die earlier than the median.

Medroxyprogesterone Actetate

A semi-synthetic medication which is close in structure and function to the naturally occurring female sex hormone, progesterone.

A synthetic steroid progestational hormone that is used especially in the treatment of amenorrhea and abnormal uterine bleeding, in conjunction with conjugated estrogens to prevent osteoporosis and relieve the symptoms of menopause. An injectable contraceptive also known as medroxyprogesterone.


Thin layer of tissue covering a surface, lining a body cavity, or dividing a space or organ.

Pericarditis is a condition in which the membrane, or sac, around your heart is inflamed.

Meninges, Plural of Meninx

Any membrane; specifically, one of the membranous coverings of the brain and spinal cord.

The brain and spinal cord are covered by 3 connective tissue layers collectively called the meninges that consist of the pia mater, the arachnoid and the dura mater. The meninges also support blood vessels and contain cerebrospinal fluid. Meningitis is an inflammation of the meninges; if severe, may become encephalitis, or inflammation of the brain.


The spread of a disease process from one part of the body to another.

The appearance of abnormal tissue growths (malignant or nonmalignant) in parts of the body remote from the site of the primary tumor.


Using an operating microscope to better visualize a small operating field or perform delicate surgery.

The examination of minute objects by means of a microscope, an instrument which provides an enlarged image of an object not visible with the naked eye.


One-thousandth of a roentgen.

The international unit of exposure for x-rays or gamma rays.


A form of application or employment of a therapeutic agent or regimen.

A method of treatment. For example, surgery and chemotherapy are treatment modalities.

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