Principles of Imaging

Question 1

4 main ways of imaging a body

Answer 1

• X- Rays.
• Sound waves.
• Magnetism.
• Radionuclide emission (gamma rays and positron emission).

Question 2

Requirements of an ideal rad tracer

Answer 2

• Minimum particulate emission.
• Photon energy between 50 – 500 ke V. - Physical half life longer than preparation time.
• Effective half life longer than imaging time.
• Suitable chemical form, stability and low toxicity.

Question 3

Why is TC99m a good tracer?

Answer 3

• Has no particulate emission.
• Generator produced.
• Has a 6 hour half life.
• 98% of gamma rays are at 140 keV.
• Similar in properties and size to an iodine ion.

Question 4

What are the stages of the patient pathway ?

Answer 4

• Referral.
• Authorisation and protocoling.
• Patient preparation.
• Radio-pharmaceutical preparation.
• Administration.
• Image acquisition.
• Image interpretation and report generation.

Question 5

Regulatory requirements for referral, author and administration

Answer 5

IRMER:
referrer req to provide adeq clinical info
justification to be made by a practition adeq trained (ARSAC holder or delegate)
Consideration for age, preg / breast feeding, prep like hyd/fasting

Question 6

Radiopharmacy prep requirements

Answer 6

• Delivered ready to administer from manufacturer (e.g. FDG).
• Prepared/labeled locally (sterile radiopharmacy).
• Patient details checked, dose checked and released for injection.

Question 7

Administration methods

Answer 7

• Ingested (e.g. gastric emptying).
• Inhaled (e.g. lung ventilation studies).
• Majority are injected.