Glossary

Glossary of Medical Terms

Below are some of the medical terms that you will come across while browsing this site. This list is by no means exhaustive, but is designed to provide you with a better understanding of the terms and procedures discussed.

Allergy: an over-reaction of the body's immune system. See allergy for more information.

Angiography: imaging of the arteries and veins of the body. See CT angiography, Digital Subtraction Angiography and vascular ultrasound.

Barium: an element which is opaque to x-rays, meaning x-rays cannot pass through. Barium is used in some x-ray procedures in the form of a water based suspension which coats surfaces. See, for example, barium meal.

B-flow: a form of ultrasound imaging which shows flowing blood as well as the vessel walls.

Biopsy: sampling of body cells or tissue. See biopsy.

Contrast: a substance which allows imaging of structures which cannot be seen using conventional imaging. Contrast may be swallowed, applied or injected. See x-ray contrast, barium, CT angiography or vascular ultrasound.

CT (Computed Tomography): a specialised form of x-ray imaging where cross-sections of the body are generated. See CT.

Doppler: a form of ultrasound where information can be obtained on flowing blood in arteries and veins. The information can be represented as Colour Doppler (where the blood flow is shown as blue and red), or Duplex (where velocity of blood flow can be measured). See vascular ultrasound.

Enema: imaging of the large bowel or colon by introducing a contrast agent via the rectum. See barium enema.

Facet: one of the posterior (at the back) joints of the spine. These joints are also called zygoapophyseal or Z joints. See facet joint injection.

Fibroadenoma: a common breast lump in younger women. It can usually be seen with mammography or ultrasound. A fibroadenoma is benign but may require biopsy for firm diagnosis.

IVP: is short for intravenous pyelogram, which investigates the urinary tract (Kidneys, ureters and bladder) using an injection of x-ray contrast. See IVP.

Mammography: low dose x-rays are used to image the internal structure of the breasts. See mammography.

Myelography: an x-ray which shows the spinal cord and spinal nerve roots using x-ray contrast. Myelograms can look at the neck or back. See myelography.

Nuchal: the skin at the back of the neck. By measuring the nuchal thickness at the time of an ultrasound done at a certain stage of pregnancy, an estimate can be made of the risk of a foetus having Down syndrome. See nuchal translucency ultrasound and Fetal Medicine Foundation.

Oncology: the medical specialty concerned with the treatment of cancer.

OPG: short for orthopantogram, which is an x-ray technique for imaging the bones of the jaws and the teeth. See OPG and Cephalometry.

Osteodensitometry: a method of measuring the bone mineral density. See DEXA and osteoporosis.

Osteoporosis: Bone mass is greatest in the young, and declines with age, particularly in women after the menopause. The most common cause of decrease in bone density is osteoporosis.

Percutaneous Nephrostomy: a method of draining an obstructed kidney by inserting a fine tube through the skin and into the collecting system of the kidney by using CT and/or x-ray, ultrasound imaging.

Radiology: traditionally, the medical specialty dealing with imaging by x-ray. There has been an explosion in many fields of radiology over the past ten to fifteen years, and radiologists now also use other imaging methods such as ultrasound, and also use imaging to perform procedures (interventional radiology).

Radiation: for our purposes, electromagnetic radiation, in particular, x-rays.

Stroke: the cutting off of blood supply to a part of the brain.

Ultrasound: uses high frequency sound to produce images of the internal structures of the body. The principle is similar to that used by a ship's Sonar.

Vascular: the arteries and veins, from large vessels like the aorta and vena cava to tiny vessels within body organs and tumours.

X-ray: a form of ionising radiation used to image some internal structures of the body. See x-ray and radiation.