Glossary of Terms

 

targeted cryoablation therapy

See cryosurgery.

technetium-99m

A radiotracer commonly used in nuclear medicine for many different types of examination. It decays within 24 hours, leaving no residual radiation.

technologist

(tek-nol-a-jist)

One trained in and using the techniques of a profession, art, or science.

temporary brachytherapy

A radiation therapy treatment for cancer in which radioactive material sealed inside a seed or pellet is placed inside the body in or near a tumor for a specified amount of time and then withdrawn. This treatment can be administered at a low dose rate (LDR) or high dose rate (HDR).

temporomandibular joint disorder

Several conditions associated with pain in the face affecting the jaw muscles, temporomandibular joints (upper temporal bone and lower mandible jaw bone that form the joint) and nerves.

tension headache

A headache in which pressure and a band-like tightness begins in the back of the head and upper neck and gradually encircles the head.

testicular torsion

The twisting of the spermatic cord that contains the vessels that supply blood to the testicles.

testis (pl. testes)

One of the two male reproductive glands that produce spermatozoa (sperm) and male hormones (testosterone). The testes are located behind the penis in the scrotum.

therapeutic radiology

A medical specialty and the study of radiation treatment of abnormal tissue (nonmalignant or cancerous) through the use of x-rays or radionuclides.

therapist

(thar-a-pist)

One professionally trained and/or skilled in the practice of a particular type of therapy.

thoracic

Refers to the chest or ribs region of the spinal column, which includes twelve bones, or vertebrae labeled T-1 through T-12.

thrombolysis

See catheter-directed thrombolysis.

thrombolytic agent

One of a group of medications used to dissolve clots within the blood vessels of the body.

thrombolytic therapy

The use of medication used to break up or dissolve clots within blood vessels.

thrombophlebitis

Inflamation of a vein that results when a blood clot, a thickened mass of blood, forms along the wall of a blood vessel.

thrombosis

The blocking of a blood vessel by a blood clot (or thrombus) that forms in a blood vessel or organ.

thrombotic stroke

A stroke that occurs when a blood clot forms in a cerebral blood vessel that is already very narrow.

thyroid gland

(thI-rOYd)

One of nine endocrine glands in the body, located in front of the neck just below the Adam's apple. It is shaped like a butterfly, with two lobes on either side of the neck connected by a narrow band of tissue. The thyroid gland produces thyroid hormones that set the rate the body carries on its necessary functions (metabolic rate). Some of the functions controlled by thyroid hormones include heart rate, cholesterol level, body weight, energy level, muscle strength, skin condition and vision.

thyroid scan

A nuclear medicine examination that helps evaluate the structure of the thyroid. The thyroid is a gland in the neck that controls metabolism, a chemical process that regulates the rate at which the body functions.

thyroid uptake

Also known as radioactive iodine uptake test (RAIU).
A nuclear medicine examination that helps evaluate the function of the thyroid. The thyroid is a gland in the neck that controls metabolism, a chemical process that regulates the rate at which the body functions.

tissue plasminogen activator (t-PA)

A blood clot-busting drug used to reduce the severity of an ischemic stroke if given within a short window of time following the onset of the stroke.

tomography

(tO-mog-ru-fE)

Making a radiographic image of a selected plane by means of reciprocal linear or curved motion of the x-ray tube and film cassette; images of all other planes are blurred ("out of focus") by being relatively displaced on the film.

tonic-clonic seizure

See grand mal seizure.

trachea

Also known as the windpipe, the tube that connects the lungs and mouth.

transabdominal

Through or across the abdomen.

transducer

(trans-dU-ser)

A hand-held device that sends and receives ultrasound signals.

transient ischemic attack (TIA)

Often referred to as a mini stroke, a TIA is a temporary blockage in blood flow to parts of the brain, usually due to plaque or a blood clot. Symptoms typically go away within a day.

transjugular intrahepatic portosystemic shunt (TIPS)

A small, tubular metal device commonly called a stent or stent-graft that is placed in the middle of the liver to connect the hepatic vein and portal vein, creating a bypass between the systemic and portal venous system. The shunt is placed in an attempt to divert blood from the intestines around the liver, decrease blood pressure within the liver and sometimes used to treat recurrent ascites.

transplant

1. To transfer from one part to another, as in grafting and transplantation.
2. The tissue or organ in grafting and transplantation.

transrectal

Passing through or performed by way of the rectum.

transvaginal

(trans-vaj-i-nal)

Across or through the vagina (the genital canal in the female, extending from the uterus to the vulva).

treatment planning

Establishment of procedures to carry out effective radiation therapy with minimal risk to healthy tissue. See also simulation.

triple A

See abdominal aortic aneurysm (AAA).

trocar

A hollow needle with a sharply pointed end that is inserted into a blood vessel, body cavity or bone. Needles, tubes or other instruments are then inserted through the trocar be inserted to reach the treatment area.

tuberculosis

A highly contagious infection transmitted through the air that attacks the lungs and other parts of the body.

tumor

A growth of abnormal cells that are either malignant or benign.

tumor ablation

The removal of a tumor.

tunneled cathether

A special type of catheter used in a vascular access procedure that is inserted inside a major vein for a period of weeks, or months so that blood can be repeatedly drawn or medication and nutrients can be injected into the patient’s bloodstream on regular basis. Unlike a standard intravenous catheter (IV) which is for short term use, a vascular access catheter is more durable and does not easily become blocked or infected. The tunneled catheter, which has a cuff at one end that stimulates tissue growth to help hold it in place, is used when access to the vein is needed for longer than three months and many times each day. This catheter is commonly used for patients requiring dialysis.

turgidity

Veins that carry blood from throughout the body to the heart rely on a series of valves that work like gates to prevent blood from flowing backwards. When valves are not working properly, the normal flow of blood slows and creates pockets of backflow, called turgidity, where clots can develop.