Diagnostic imaging Quiz

Describe what a gas looks like on a radiograph and briefly explain the reason for its appearance ..

Gas appears black on a radiograph due to its low specific gravity and low atomic number

Describe what bone looks like on a radiograph and briefly explain the reason for its appearance

Bone appears white on a radiograph due its its high specific gravity and high atomic number (bone is a dense material)

Identify the positive contrast agent in this image

The positive contrast agent is white

State what the small black dots are within the white contrast media within this image

Air bubbles which may have entered the bladder during the administration of the contrast agent

State the most used contrast agent within the gastrointestinal tract

Barium sulphate

Briefly explain why a positive contrast agent should be prepared away from the patient and radiography equipment

To prevent splashing/contamination on the patient and/or radiography equipment that may appear on the radiograph

Briefly explain why a non-soapy enema should be administered in preparation got large intestinal and urinary tract contrast studies

A non-soapy enema will produce less air bubbles than a soapy enema. Air bubbles may make interpretation of the radiograph difficult.