Glossary of Terms

Abscess
A localized collection of pus in any part of the body surrounded by inflamed tissue

Aspiration
Withdrawal of a fluid from the body by suction, usually through a needle or a syringe.

Barium
A chalky liquid which outlines various parts of the digestive tract on an X-ray. It is not absorbed by the body. It is used to study the esophagus, stomach, small intestine, and large bowel.

Biopsy
The removal and examination of a piece of tissue taken the body for diagnostic purposes

Conscious Sedation
Medication used to help one relax during a procedure, without putting one to sleep.

Contrast
A radiopaque substance used during an X-ray exam (or some MRI exams) to provide visual contrast in the pictures of different tissues and organs. Can be given orally or intravenously.

CT
A CT or CAT (Computer Assisted Tomography) Scan is a specialized X-Ray that appears in slices. This technique uses X-rays to generate computerized images of all parts of the body.

Cyst
A sac or vesicle in the body.

Doppler
An ultrasound method of examining blood vessels.

Faculty
Staff physicians with academic appointment at a medical school. Titles vary by appointment (i.e. Assistant Professor, Professor, Clinical Researcher)

Fellow
A fully-licensed physician seeking additional training.

GI
An X-ray exam of the upper part of the digestive tract.

Infuse
To introduce a solution into the body through a vein.

Ionizing Radiation
Ionizing radiation is radiation with enough energy so that during an interaction with an atom it can remove tightly bound electrons from their orbits, causing the atom to become charged or ionized.

I.V.
Abbreviation for intravenous.

Millirad
A unit of measuring radiation dose equal to one thousandth of a RAD.

Myelogram
An X-ray of the spinal cord after the injection of a radiopaque substance into the subarachnoid space.

Non-ionizing radiation
Non-ionizing radiation is radiation without enough energy to remove tightly bound electrons from their orbits around atoms. Examples are microwaves and visible light.

NSAID
Non-steroidal, anti-inflammatory drugs, such as aspirin, Motrin, Indocin and other pain killers.

Pyelogram, IV Urogram, IVP
An X-ray of the pelvis, showing the kidney and associated structures, after injection of a radiopaque dye.

RAD (Radiation Absorbed Dose)
An acronym for Radiation Absorbed Dose. A unit which measures radiation in terms of the absorbed dose.

Radiation
Radiation is energy in the form of high speed particles and electromagnetic waves. Radiation is encountered by us everyday (i.e. ultraviolet, microwave, television) but these examples do not cause ionizations of atoms because they do not cary enough energy to separate molecules or remove electrons from atoms.

Radiologist
A physician who interprets X-ray images to diagnose disease. Today’s radiologists use a variety of other modalities such as CT, Ultrasound, MRI and Nuclear Medicine.

Radiopaque
Anything that does not allow the penetration of X-rays.

REM (Roentgen Equivalent Man)
The REM is a unit used to derive a quantity called equivalent dose. This relates to the absorbed dose in human tissue to the effective biological damage of the radiation. Not all radiation has the same biological effect, even for the same amount of absorbed dose.

Roentgen (R)
The roentgen is a unit used to measure a quantity called exposure. This can only be used to describe an amount of gamma and X-rays, and only in air.

Roentgen, Wilhelm Conrad
The scientist credited with the discovery of X-rays in 1895. He received the Nobel Prize in 1901.

Stereotactic
The technique of viewing objects from two slightly different angles ot give a perception of depth.

X-ray
An x-ray is an electromagnetic wave or photon not emitted from the nucleus, but normally emitted by energy changes in electrons. These energy changes are either in electron orbital shells that surround an atom or in the process of slowing down such as in an X-ray machine.