Glossary of Terms

4 July 2015


A

artery
Blood vessel that transports blood from the heart to the organs.

abscess

A collection of pus in any part of the body.

alpha particles

helium nucleus given off by certain radioactive substances

analgesics

Medication to reduce pain; painkillers.

anaesthetic

A drug that causes loss of sensation with or without the loss of consciousness.

anal orifice

The lower opening of the large bowel

angiogram, angiography

A technique that shows up blood vessels on an X- ray. It is done by injecting X-ray dye (contrast) into the blood vessel. An angiogram is a picture of one or more blood vessels, which are filled with X-ray dye. Angiography usually refers to arteries; venography is the study of veins using X-ray dye.

anti-cancer drugs
Medication used to treat or control the growth of cancer cells

arteriogram, arteriography
An X-ray of an artery after the injection of dye.

aspirate, aspiration

Withdrawal of a fluid from the body by suction, usually though a needle using a syringe.

arthrogram, arthrography
The visualisation of a joint by X-ray after the injection of dye into the joint.

B

background radiation
The amount of radiation we receive from natural radiation sources in the earth, air and diet.

barium meal
The examination of the oesophagus, stomach and the beginning of the small intestine.

barium enema

The radiological examination used to demonstrate the large intestine.

barium sulphate

This is a white liquid which outlines various parts of the digestive tract on an X-ray. It can be swallowed to study the oesophagus, stomach and small intestine. It can be used as an enema to study the large intestine. It is inert and is not absorbed by the body.

beta particle

An electron emitted by the nucleus of a radioactive substance.

betatron
Device to accelerate an electron beam to reduce high energy X-rays or electron beams for cancer treatment

bone mass
The amount of bone present within a particular region.

biopsy
The removal and examination of a piece of tissue taken from a living body for diagnostic purposes.

brachytherapy
Radiation therapy at short distances with the use of inserted radioactive sources

breast augmentation
Plastic surgery to increase the size of the breasts.

C

cannulation
Passing a fine tube through the artery or vein or into the opening of the ducts.

cardiologist
The medical specialist who treats diseases of the heart.

catheter

A fine plastic tube, which is used for angiography, opacification of ducts or to drain collections.

cerebral angiography

Examination to demonstrate blood vessels of the brain

chemotherapeutic drugs

See anti-cancer drugs

chemoembolization

Method of treating cancer by injecting cancer drugs through the blood vessels

cobalt-60 units

Devices to treat cancer using gamma rays from artificial radioactive materials

colon

The large intestine (large bowel).

CT
(computerised tomography) Also known as CAT scans (for Computer Assisted Tomography). This technique uses X-rays to generate computerised images (pictures) of all parts of the body.

conscious sedation
Intravenous medication used to help relax the patient during a procedure, without putting the patient to sleep. Usually associated with angiography procedures.

contrast or contrast medium or “dye”
A substance used during an X-ray examination (or some MRI exams) to provide better visualisation or pictures of different tissues and organs. Can be given orally, rectally or intravenously (by injection)

core biopsy
A procedure which is used to get samples of tissue from the breast to look for cancerous cells.

coronary angiography, cardiac catheterization

This is a study of the blood vessels which supply the muscle of the heart (coronary arteries). Cardiac catheterization refers to the technique of performing coronary angiography, whereby catheters are threaded into the heart and coronary arteries.

cyst
A sac or vesicle in the body. (A collection of fluid in the body)

cytology

The process of examining the cells from biopsy specimens to make diagnoses.

D

dacyrocystography
An examination to demonstrate the tear ducts of the eyes

dense, denser
This refers to the density of tissue.

DEXA (dual energy X-ray absorptiometry)
A method used to determine the amount of bone present.

diaphanography

Examination of the breast using special light

doppler studies

An ultrasound method of examining blood flow in vessels. No X-rays are involved.

ductography / galactography

Examination of the ducts in the breast

duodenum

The beginning of the small intestine, just after the stomach.

dye
See contrast/ contrast medium.

E

echocardiogram, echocardiography
An ultrasound examination using ultrasound waves to visualise the structure and function of the heart.

embolization
See vascular embolization

endoscopes, endoscopy
The instrument used by medical specialists to examine the stomach or large bowel. The procedure is called endoscopy.

enteroclysis
Examination to visualize the small bowel

epileptic
A person who suffers from recurrent fits.

enema
Any solution which is introduced into the large bowel via the rectum.

ERCP (endoscopic retrograde cholangiopancreatogram)
Introduction of dye into the ducts draining the liver and pancreas using an endoscope.

external radiotherapy

Radiotherapy treatment from the outside

F

fallopian tubes
A pair of slender tubes through which ova pass from the ovaries to the uterus in the female.

Fellow

A fully-licensed physician seeking additional specialised training.

fluoroscopy

An X-ray based method that allows “moving” radiological studies to be recorded and replayed.

foetus

The baby in the uterus

G

gadolinium

A substance which is used in the making of the contrast medium used for MR imaging.

galactography
See ductography

gallbladder series
A series of X-rays of the gallbladder, taken after the gallbladder has been outlined with a special X-ray dye. The dye is taken by mouth the night prior to the study.

gamma camera

A special device used to detect radiation in Nuclear Medicine studies.

gamma rays
This is the radiation emitted from some types of radioactive substances. It is similar to X-rays in other respects.

guide wire
A special type of wire, which is used to help in the placement of catheters.

H

histology, histologic

Pertaining to the study of microscopic structures of tissue

hysterosalpingography
The radiological study to demonstrate the cavity in the womb (uterus) and the tubes (fallopian).

I

ileocaecal junction

The area where the small bowel ends and the large bowel begins.

infertility
Inability to become pregnant. Primary infertility is the term used for women who have never been pregnant whereas the term secondary infertility refers to women who have previously had a pregnancy.

infrared thermography
Technique of examining the breast based on the detection of heat & microwaves

infuse, infusion

To introduce a solution into the body through a vein.

internal radiotherapy
Radiotherapy by placing radioactive substances close or within the cancer

interventional procedures
Special radiological procedures which are used to treat the patient.

invasive
Term used to describe those radiological procedures where there is use of needles to puncture.

intravenous urography
The radiological examination used to demonstrate the kidneys, ureters and bladder.

iodinated contrast medium
See contrast medium/dye

ionising radiation/ionisation
Radiation which causes electrons to be removed from atoms or molecule

i.v.

An abbreviation for intravenous. This means introduction of a substance into a vein.

J


jaundice

Yellowish discolouration of the skin and eyes.

L

linear accelerators

Devices to treat cancer by producing high energy X-rays

M

magnetic resonance imaging (MRI)

An examination which uses radio waves and a strong magnetic field to generate images.

mammogram, mammography
A mammogram is an X-ray of the breast. It is an examination performed to detect breast cancer and other abnormalities of the breast.

mastalgia
Painful sensation in the breast.

menopause, menopausal

This is the period when the women’s ovaries produce less hormone resulting in cessation of the menstrual periods. The period after this is called post-menopausal while the period during it is termed perimenopausal.

microwave thermography

See infrared thermography

MHz (megahertz)

A measure of the frequency (cycles per second) of sound. Equal to 1 million cycles/second.

millirad

An old unit of measuring radiation dose equal to one thousandth of a rad.

minimally invasive therapy
The term used to describe the group of procedures used to treat disease without the need for open surgery.

myelogram

An X-ray of the spinal cord after the injection of contrast into the spinal canal. This examination will outline the spinal cord and nerve roots.

N

nerve roots

These are the part of the nerves as they come of the spinal cord.

NSAID (Non-Steroidal Anti-Inflammatory Drugs)
e.g. aspirin, paracetamol, and other pain-killers. These are distinct from cortisone, which is an anti-inflammatory steroid.

nuclear medicine imaging

A group of studies where the patient receives an intravenous injection of a very small amount of radioactive substance following which scans are obtained with a gamma camera.

O


oncology

The science of cancer

osteoporosis

Is the condition of reduced bone density or bone loss which increases the risk of fracture with little or no trauma.

P

pathologist

The medical specialist who examines the tissues obtained from biopsy or surgery to make a diagnosis.

perimenopausal

See menopause

peripheral angiography

Examination to show the blood vessels of the arms & legs

PTC (percutaneous transhepatic cholangiogram)

An invasive procedure to look at the ducts draining the liver.

pyelogram

An X-ray of the abdomen, showing the kidney and associated structures, after injection of a radiopaque dye.

Q

quantitative CT

A method to determine the amount of bone using CT.

R


radiation oncologist

A medical specialist who is an expert in treating cancer using radiotherapy and anticancer drugs.

radiation therapy/radiotherapy
Here, large doses of X-rays are used to treat cancer by killing cancer cells. This treatment is not usually part of a radiology department, and treatment is given by physicians who are specialised in this field (radiation oncologists).

radioactive
A substance that is able to spontaneously break down and emit radiation.

radioactive drugs

Drugs which are attached to radioactive substances. These may be used to treat certain diseases.

radioactive materials/substances
See radioactive/radioactive drugs

radiograph/ radiography

The commonly referred to X-ray picture. Radiography is the act of producing the X-ray picture. It may also be used to describe the speciality of those involved in helping the radiologist in producing the pictures.

radiographer

A person trained in the technique of producing an image with the use of X-rays, ultrasound or MRI.

radiologist
A physician who interprets X-ray images to diagnose disease. In addition to interpreting the original kinds of X-ray films, radiologists today use a variety of other modalities such as MRI, ultrasound, and nuclear medicine.

radioisotope

A substance which gives off or emits radiation.

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

radiotherapy and oncology

The treatments used to treat cancer.

Roentgen, Wilhelm Conrad
The scientist who discovered X-rays in 1895. Received Nobel prize in 1901.

S

scan

Term used to describe the computerised images (pictures) generated by CT, MRI, ultrasound, and nuclear medicine studies. These might be referred to as a “CT scan,” “MR scan,” “thyroid scan,” “bone scan,” and so forth.

sciatica
Pain radiating from the lower back to deep within the buttock and back of the thigh, along the course of the sciatic nerve.

sialography
Examination of the ducts of the salivary glands

single photon absorptiometry
One of the methods used to measure the bone density.

Sinus
Abnormal track opening on the skin

sinography
Examination of the sinus

SPECT (Single Photon Emission Computed Tomography)
A nuclear medicine procedure in which the gamma camera rotates around the patient and takes pictures from many angles, which a computer then uses to form a tomographic (cross-sectional) image. The calculation process is similar to that in X-ray Computed Tomography (CT) and in Positron Emission Computed Tomography (PET).

spinal canal

The canal within the column of back bones; filled with fluid and the spinal cord.

spinal cord
The part which allows the transmission and reception of signals form the brain to the rest of the body. This lies within the spinal canal.

stereotactic

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

T

therapeutic

See interventional.

thrombus
A blood clot in a blood vessel.

thrombolysis
Dissolving blood clots using chemicals

tomography

A special kind of imaging which allows a section of the body to be obtained at different levels.

T tube cholangiogram
The radiological examination done to look at the ducts draining the liver after surgery through a tube placed at the time of surgery.

transducer

An instrument which converts electrical energy into mechanical energy. Also acts as a transmitter and receiver of ultrasound information.

U

ultrasound, ultrasonography

This technique uses sound waves to make pictures of the body organs. Since no ionising radiation (X-rays) is used, it is ideal for looking at pregnant women and their foetuses, but also has many other uses. It is often used for the neck, abdomen, pelvis, and soft tissues including blood vessels in the arms and legs.

ultrasound probe
See transducer

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

V

venogram, venography

The images of and study of the veins of the body respectively.

vascular
Referring to a person’s system of blood vessels: arteries, veins, and capillaries.

vascular embolization
Occluding blood supply to cancers or other abnormal areas

varicose veins
A condition in which the veins become tortuous and dilated. This most commonly occurs in the legs

W

wavelength

Distance between peaks in a wave. Shorter wavelength corresponds to higher frequency and thus higher radiation energy