NUCLEAR MEDICINE BOARD EXAM SCRIPT 2025/2026
QUESTIONS WITH ANSWERS GRADED A+
✔✔Pagets on bone scan - ✔✔enlarged hot long bone or hemipelvis
"mickey mouse" vertebrae (body and post elements)
✔✔early and late AVN on bone scan - ✔✔Early and late are cold
middle may be hot (from repair)
✔✔osteoid osteoma on bone scan - ✔✔double density
✔✔BENIGN BONE LESIONS ON BONE SCAN
HOT or COLD?
fibrous dysplasia
bone cyst without fracture
giant cell tumor
ABC
osteoblastoma
osteoid osteoma - ✔✔all hot except bone cyst without fracture
✔✔decreased soft tissue uptake vs. increased soft tissue uptake on bone scan -
✔✔decreased
-metastatic superscan
increased soft tissues
-metabolic superscan (kidney disease)
skull hot on metabolic (from PTH)
✔✔causes of triple phase positive bone scan - ✔✔osteomyelitis
fracture
tumor
osteoid osteoma
charcot joints
RSD or CRPS
✔✔preferred nucs agent for spine osteomyelitis - ✔✔Gallium (In-WBC can be false
negative)
✔✔which patients sometimes require a 4th phase bone scan (24 hours)? - ✔✔diabetics
give time for soft tissue tracer to clear
,✔✔critical organ of In-WBC - ✔✔spleen
✔✔agent for V/Q perfusion portion?
biologic half life of the agent? - ✔✔Tc99m-MAA
4 hours biologic half life
✔✔ventilation with Xenon-133
physical vs. bio half lives
when doing V/Q, is xenon of MAA done first? - ✔✔physical: 5.3 days
bio: 30 seconds (exhaled)
ALWAYS do XENON first, energy is around 80kEv (will be overpowered by Tc99 if Tc
done first)
✔✔Tc99m-DTPA ventilation - ✔✔allows for different views
tends to clump
DO BEFORE THE PERFUSION
✔✔size of V/Q scan MAA particles
when is number of particles reduced - ✔✔10-100 micrometers (any bigger will block
arterioles)
reduce for kids and pregnancy, or R>L shunts, or pulm HTN
✔✔multiple scattered hot spots on V/Q perfusion - ✔✔clumped MAA, from tech drawing
back blood into the syringe before injection
✔✔liver uptake on Xenon-133 ventilation - ✔✔hepatic steatosis
✔✔unilateral whole lung perfusion defect - ✔✔get cross sectional imaging to exclude
large central obstructing cancer
technically speaking this is low probability for PE
✔✔PIOPED criteria - ✔✔
, ✔✔gallium-67
what is it used for?
half life?
energy peaks?
critical organ? - ✔✔used for tumor/inflammation/infection
iron analogue (acute phase reactant)
half life 78 hours
peaks at 100, 200, 300, 400 (technically 93, 184, 300, 393)
critical organ is the colon
✔✔radiotracer uptake in lacrimal glands - ✔✔typical of gallium scan
✔✔sarcoidosis on gallium scan - ✔✔hilar and paratracheal uptake ("lambda")
"panda sign" - lacrimal glands, parotids, nasopharynx
-also seen with sjogrens or treated lymphoma
✔✔Gallium appearance with PCP vs. Kaposi sarcoma - ✔✔PCP
-gallium hot
Kaposi
-gallium negative, but thallium positive
✔✔preferred nucs agent for abdominal or pelvic infections - ✔✔Indium-WBC
gallium will have decreased sensitivity because of normal GI uptake
✔✔Thyroid imaging
I-131 vs. I-123 vs. Tc99m
energies?
emission?
half lives? - ✔✔I-131
-high energy (364 keV) - think "1 year is 365 days"
-beta emitter
QUESTIONS WITH ANSWERS GRADED A+
✔✔Pagets on bone scan - ✔✔enlarged hot long bone or hemipelvis
"mickey mouse" vertebrae (body and post elements)
✔✔early and late AVN on bone scan - ✔✔Early and late are cold
middle may be hot (from repair)
✔✔osteoid osteoma on bone scan - ✔✔double density
✔✔BENIGN BONE LESIONS ON BONE SCAN
HOT or COLD?
fibrous dysplasia
bone cyst without fracture
giant cell tumor
ABC
osteoblastoma
osteoid osteoma - ✔✔all hot except bone cyst without fracture
✔✔decreased soft tissue uptake vs. increased soft tissue uptake on bone scan -
✔✔decreased
-metastatic superscan
increased soft tissues
-metabolic superscan (kidney disease)
skull hot on metabolic (from PTH)
✔✔causes of triple phase positive bone scan - ✔✔osteomyelitis
fracture
tumor
osteoid osteoma
charcot joints
RSD or CRPS
✔✔preferred nucs agent for spine osteomyelitis - ✔✔Gallium (In-WBC can be false
negative)
✔✔which patients sometimes require a 4th phase bone scan (24 hours)? - ✔✔diabetics
give time for soft tissue tracer to clear
,✔✔critical organ of In-WBC - ✔✔spleen
✔✔agent for V/Q perfusion portion?
biologic half life of the agent? - ✔✔Tc99m-MAA
4 hours biologic half life
✔✔ventilation with Xenon-133
physical vs. bio half lives
when doing V/Q, is xenon of MAA done first? - ✔✔physical: 5.3 days
bio: 30 seconds (exhaled)
ALWAYS do XENON first, energy is around 80kEv (will be overpowered by Tc99 if Tc
done first)
✔✔Tc99m-DTPA ventilation - ✔✔allows for different views
tends to clump
DO BEFORE THE PERFUSION
✔✔size of V/Q scan MAA particles
when is number of particles reduced - ✔✔10-100 micrometers (any bigger will block
arterioles)
reduce for kids and pregnancy, or R>L shunts, or pulm HTN
✔✔multiple scattered hot spots on V/Q perfusion - ✔✔clumped MAA, from tech drawing
back blood into the syringe before injection
✔✔liver uptake on Xenon-133 ventilation - ✔✔hepatic steatosis
✔✔unilateral whole lung perfusion defect - ✔✔get cross sectional imaging to exclude
large central obstructing cancer
technically speaking this is low probability for PE
✔✔PIOPED criteria - ✔✔
, ✔✔gallium-67
what is it used for?
half life?
energy peaks?
critical organ? - ✔✔used for tumor/inflammation/infection
iron analogue (acute phase reactant)
half life 78 hours
peaks at 100, 200, 300, 400 (technically 93, 184, 300, 393)
critical organ is the colon
✔✔radiotracer uptake in lacrimal glands - ✔✔typical of gallium scan
✔✔sarcoidosis on gallium scan - ✔✔hilar and paratracheal uptake ("lambda")
"panda sign" - lacrimal glands, parotids, nasopharynx
-also seen with sjogrens or treated lymphoma
✔✔Gallium appearance with PCP vs. Kaposi sarcoma - ✔✔PCP
-gallium hot
Kaposi
-gallium negative, but thallium positive
✔✔preferred nucs agent for abdominal or pelvic infections - ✔✔Indium-WBC
gallium will have decreased sensitivity because of normal GI uptake
✔✔Thyroid imaging
I-131 vs. I-123 vs. Tc99m
energies?
emission?
half lives? - ✔✔I-131
-high energy (364 keV) - think "1 year is 365 days"
-beta emitter
