Definition of Glomus jugulare tumor:

A glomus jugulare tumor is a small, ball-like swelling in the area of the middle ear.

Causes, incidence, and risk factors:

A glomus jugulare tumor grows in the bones of the skull where nerves are located. Specifically, the tumor occurs in part of the jugular vein (a large vein in the neck) or along a certain nerve on the side of the skull (temporal bone).

Both of these areas contain glomus bodies, which are nerve fibers that normally respond to change in body temperature or blood pressure. A person with a glomus jugulare tumor may have a feeling of a loud pulsing in the ear.

These tumors usually occur later in life, around age 60 or 70. The cause of a glomus jugulare tumor is unknown. There are no known risk factors.