FINAL EXAM - MAIN THINGS Questions with Correct Solutions
Question:
1. Formula for geometric mean
Answer:
(Anterior counts × Posterior counts) — corrects for depth/attenuation.
Question:
2. Why geometric mean is used with opposing views
Answer:
It reduces the effect of how deep the organ is.
Question:
3. Geometric mean calculation (Anterior 10,000, Posterior 6,400)
Answer:
8,000 counts — (10,000 × 6,400).
Question:
4. Lu-177 Pluvicto indication
Answer:
PSMA-positive metastatic prostate cancer — targets PSMA-expressing cells.
Question:
5. Lu-177 Pluvicto target
Answer:
PSMA — highly expressed on many prostate cancer cells.
Question:
6. Lu-177 therapeutic radiation type
Answer:
Beta radiation — damages nearby tumor cells.
Question:
7. Pluvicto normal distribution/excretion
Answer:
Kidneys, salivary/lacrimal glands, liver/spleen, and urinary tract.
,Question:
8. Pluvicto organ monitoring requirement
Answer:
Kidneys — primarily cleared through urine.
Question:
9. Pre-Pluvicto therapy labs
Answer:
CBC and renal/hepatic function — checks marrow and organ function.
Question:
10. Major hematologic concern with Pluvicto
Answer:
Myelosuppression — radiation can decrease blood cell counts.
Question:
11. Lung perfusion imaging radiopharmaceutical
Answer:
Tc-99m MAA — particles temporarily lodge in pulmonary capillaries.
Question:
12. Preferred position for Tc-99m MAA injection
Answer:
Supine — gives more even lung perfusion distribution.
Question:
13. Common ventilation agents
Answer:
Xe-133 gas and Tc-99m DTPA aerosol.
Question:
14. Xe-133 vs Tc-99m DTPA aerosol appearance
Answer:
Xe is a gas with wash-in/washout; DTPA aerosol can show central airway deposition.
Question:
15. Air trapping finding with Xe-133
, Answer:
Persistent activity on washout images — xenon remains trapped.
Question:
16. Hot central airway/'hot esophagus' pattern cause
Answer:
Swallowed/deposited Tc-99m DTPA — aerosol contamination/deposition.
Question:
17. Matched V/Q defect definition
Answer:
Ventilation AND perfusion are decreased in the same area.
Question:
18. Mismatched V/Q defect definition
Answer:
Normal ventilation with decreased perfusion — classic concern for PE.
Question:
19. Pulmonary embolism perfusion defect shape
Answer:
Wedge-shaped/segmental — follows pulmonary vascular anatomy.
Question:
20. Stripe sign meaning
Answer:
Perfusion remains along the pleural edge — argues against PE in that defect.
Question:
21. Common Tc-99m MPI tracers
Answer:
Tc-99m sestamibi and tetrofosmin — localize in viable myocardium.
Question:
22. Reversible MPI defect definition
Answer:
Ischemia — abnormal stress but improves at rest.
Question:
1. Formula for geometric mean
Answer:
(Anterior counts × Posterior counts) — corrects for depth/attenuation.
Question:
2. Why geometric mean is used with opposing views
Answer:
It reduces the effect of how deep the organ is.
Question:
3. Geometric mean calculation (Anterior 10,000, Posterior 6,400)
Answer:
8,000 counts — (10,000 × 6,400).
Question:
4. Lu-177 Pluvicto indication
Answer:
PSMA-positive metastatic prostate cancer — targets PSMA-expressing cells.
Question:
5. Lu-177 Pluvicto target
Answer:
PSMA — highly expressed on many prostate cancer cells.
Question:
6. Lu-177 therapeutic radiation type
Answer:
Beta radiation — damages nearby tumor cells.
Question:
7. Pluvicto normal distribution/excretion
Answer:
Kidneys, salivary/lacrimal glands, liver/spleen, and urinary tract.
,Question:
8. Pluvicto organ monitoring requirement
Answer:
Kidneys — primarily cleared through urine.
Question:
9. Pre-Pluvicto therapy labs
Answer:
CBC and renal/hepatic function — checks marrow and organ function.
Question:
10. Major hematologic concern with Pluvicto
Answer:
Myelosuppression — radiation can decrease blood cell counts.
Question:
11. Lung perfusion imaging radiopharmaceutical
Answer:
Tc-99m MAA — particles temporarily lodge in pulmonary capillaries.
Question:
12. Preferred position for Tc-99m MAA injection
Answer:
Supine — gives more even lung perfusion distribution.
Question:
13. Common ventilation agents
Answer:
Xe-133 gas and Tc-99m DTPA aerosol.
Question:
14. Xe-133 vs Tc-99m DTPA aerosol appearance
Answer:
Xe is a gas with wash-in/washout; DTPA aerosol can show central airway deposition.
Question:
15. Air trapping finding with Xe-133
, Answer:
Persistent activity on washout images — xenon remains trapped.
Question:
16. Hot central airway/'hot esophagus' pattern cause
Answer:
Swallowed/deposited Tc-99m DTPA — aerosol contamination/deposition.
Question:
17. Matched V/Q defect definition
Answer:
Ventilation AND perfusion are decreased in the same area.
Question:
18. Mismatched V/Q defect definition
Answer:
Normal ventilation with decreased perfusion — classic concern for PE.
Question:
19. Pulmonary embolism perfusion defect shape
Answer:
Wedge-shaped/segmental — follows pulmonary vascular anatomy.
Question:
20. Stripe sign meaning
Answer:
Perfusion remains along the pleural edge — argues against PE in that defect.
Question:
21. Common Tc-99m MPI tracers
Answer:
Tc-99m sestamibi and tetrofosmin — localize in viable myocardium.
Question:
22. Reversible MPI defect definition
Answer:
Ischemia — abnormal stress but improves at rest.
