Nuclear Medicine Exam UPDATED ACTUAL Questions and CORRECT Answers
imaging differs from those that employ other ionising
2024 Aug Exam
Question 1: c) In Nuclear Medicine what are the proper-
ties of an ideal radiotracer?[6 Marks]
2024 Aug Exam
Question 3: a) Discuss the ways in which Nuclear Medicine
,Specific biological targeting Known excretion route
The radiotracer should consist of a biological molecule The tracer should have predictable pharmacokinetics and
(e.g. DMSA, phosphonates) that binds specifically to be excreted via known pathways (e.g. renal or hepatic) to
the organ, tissue, or cellular process of interest, simplify dosimetry and reduce risk. 1 mark
ensuring ac-curate localisation. 1 mark
Minimal radiation to patient and others
Short physical half-life The radiation dose should be as low as reasonably prac-
The radionuclide component (e.g. Tc-99m) should ticable (ALARP), and the tracer should localise primarily to
decay quickly to minimise radiation exposure while still the target site to limit dose to non-target tissues. 1 mark
allowingenough time for imaging. 1 mark
Compatibility with imaging systems
Stable binding It should emit radiation (usually γ-rays) of appropriate en-
The biological compound and radionuclide must ergy (100-500 keV) detectable by standard nuclear medi-
remain chemically bound during circulation and cine equipment (e.g. gamma camera, SPECT, PET). 1 mark
imaging to pre- vent false results. 1 mark
radiation methods.[3 Marks]
, Emission vs. transmission imaging
Nuclear medicine detects radiation emitted from within
the body by radiotracers, whereas CT and X-ray detect
radiation transmitted through the body from an external
source. 1 mark
Physiological vs. anatomical information
Nuclear medicine primarily shows physiological function
(e.g. metabolism, perfusion), while methods like CT and
MRI mainly provide anatomical structure. 1 mark
Radiotracers vs. external beams
Patients in nuclear medicine receive radiotracers (usual-
ly by injection), which localise to specific tissues. Other
imaging methods (e.g. X-ray, CT) rely on external beams
of ionising radiation that pass through the body. 1 mark
Radiotracer administration
A radiotracer such as ~100 MBq of 99mTc-MAG3 is ad-
ministered intravenously. It is taken up by the kidneys and
excreted through the urinary system. 1 mark
Dynamic imaging setup
A gamma camera captures images for 20 minutes in 1-10
2024 Aug Exam second frames immediately after injection to track radio-
Question 3: b) Demonstrate how scintigraphy is used to tracer uptake and excretion in real time. 1 mark
Collimator selection
A Low Energy All Purpose (LEAP) collimator is used to
optimise sensitivity over resolution during the dynamic
scan. 1 mark
Region of interest analysis
imaging differs from those that employ other ionising
2024 Aug Exam
Question 1: c) In Nuclear Medicine what are the proper-
ties of an ideal radiotracer?[6 Marks]
2024 Aug Exam
Question 3: a) Discuss the ways in which Nuclear Medicine
,Specific biological targeting Known excretion route
The radiotracer should consist of a biological molecule The tracer should have predictable pharmacokinetics and
(e.g. DMSA, phosphonates) that binds specifically to be excreted via known pathways (e.g. renal or hepatic) to
the organ, tissue, or cellular process of interest, simplify dosimetry and reduce risk. 1 mark
ensuring ac-curate localisation. 1 mark
Minimal radiation to patient and others
Short physical half-life The radiation dose should be as low as reasonably prac-
The radionuclide component (e.g. Tc-99m) should ticable (ALARP), and the tracer should localise primarily to
decay quickly to minimise radiation exposure while still the target site to limit dose to non-target tissues. 1 mark
allowingenough time for imaging. 1 mark
Compatibility with imaging systems
Stable binding It should emit radiation (usually γ-rays) of appropriate en-
The biological compound and radionuclide must ergy (100-500 keV) detectable by standard nuclear medi-
remain chemically bound during circulation and cine equipment (e.g. gamma camera, SPECT, PET). 1 mark
imaging to pre- vent false results. 1 mark
radiation methods.[3 Marks]
, Emission vs. transmission imaging
Nuclear medicine detects radiation emitted from within
the body by radiotracers, whereas CT and X-ray detect
radiation transmitted through the body from an external
source. 1 mark
Physiological vs. anatomical information
Nuclear medicine primarily shows physiological function
(e.g. metabolism, perfusion), while methods like CT and
MRI mainly provide anatomical structure. 1 mark
Radiotracers vs. external beams
Patients in nuclear medicine receive radiotracers (usual-
ly by injection), which localise to specific tissues. Other
imaging methods (e.g. X-ray, CT) rely on external beams
of ionising radiation that pass through the body. 1 mark
Radiotracer administration
A radiotracer such as ~100 MBq of 99mTc-MAG3 is ad-
ministered intravenously. It is taken up by the kidneys and
excreted through the urinary system. 1 mark
Dynamic imaging setup
A gamma camera captures images for 20 minutes in 1-10
2024 Aug Exam second frames immediately after injection to track radio-
Question 3: b) Demonstrate how scintigraphy is used to tracer uptake and excretion in real time. 1 mark
Collimator selection
A Low Energy All Purpose (LEAP) collimator is used to
optimise sensitivity over resolution during the dynamic
scan. 1 mark
Region of interest analysis
