EXTRA-AXIAL
The space located outside the brain tissue but under the skull. There are two extraaxial spaces - the subdural and epidural space.
EXTRA-OCULAR
The space that immediately surrounds the eye ball.
EXTRA-OCULAR MUSCLES
The muscles of the eye ball.
EXTRACAPSULAR RUPTURE
This is a type of breast implant rupture where the silicone leaks out of the implant bag AND out of the implant capsule. This may be seen on mammogram, ultrasound, or MRI. Please see "capsule" and "intracapsular rupture" for more information.
EXTRAHEPATIC
Outside of the liver. For example, extrahepatic bile duct means portion of the bile duct (draining tubes for gallbladder "juice") that is located outside of the liver.
EXTRAPERITONEAL
Outside of the peritoneum (sac that contains our abdominal organs and intestine).
EXTREMELY DENSE
This phrase is used in the standard sentence, "The breasts are extremely dense, which lowers the sensitivity of mammography." It means that the breast is composed of more than 75% glandular tissue and less than 25% fat. Cancer looks like a white spot on a mammogram. Normal glandular tissue is also white on a mammogram. When there is more glandular tissue in the breast, cancer is harder to see/detect. As an analogy, imagine trying to spot a white bear when it is snowing outside (in the North Pole). If it is snowing lightly, the white bear should be easy to detect. If there is a raging snow storm (blizzard), the white bear will be difficult to detect. Back to the mammogram...Since there is more than 75% glandular tissue, breast cancer may be more difficult to detect in a breast that is "extremely dense".
FACET
Is a joint consisting of two pieces of bone towards the back of the spine. Often they become "hypertrophied" or thickened as part of the aging process and arthritis. Along with a thickened ligamentum flavum, they contribute to a narrowing or stenosis of the spinal canal.
FACETECTOMY
A surgical procedure that removes the facet bones.
FACETITIS
In infection of the facet joints.