CT Dosimetry Exam Actual Questions
and Answers 2026
Effective Dose -
correct answer ✅- Overall probability of fatality to a population
- How each organ absorbs radiation
Why is CT of interest? -
correct answer ✅- Increased frequency of use
- 1972
- Rapid evolution in tech performance
- Rapid evolution in clinical applications
- Initial scan took 5 minutes (generation 1): now there are sub-
second acquisitions
- Increased speed of acquisition
- Better image quality
- Highly reliable info
- Exam tolerated by patients
However... -
correct answer ✅- CT has high doses
- High absorbed dose in tissues- organs might be irradiated that are
not part of the exam
, CT Dosimetry Exam Actual Questions
and Answers 2026
- Incident radiation up to 360 degree rotation
- Superficial tissue like breasts can receive high doses
- Short acquisition times do not mean low doses
- Relatively high effective doses
- More radiation to sensitive organs
- Procedure can be repeated several times
- Non contrast vs contrast - patients might have to have more than
1 scan
- Shorter scanning time does not mean less radiation dose because
we would increase the mAs = more radiation
CT Dose Quantities -
correct answer ✅- CTDI: Computed tomography dose index
- CTDI100: with a 100mm ionisation chamber
- CTDIW: weighted
- CTDI Vol: volume (used in spiral/helical)
- Dose Length Product
and Answers 2026
Effective Dose -
correct answer ✅- Overall probability of fatality to a population
- How each organ absorbs radiation
Why is CT of interest? -
correct answer ✅- Increased frequency of use
- 1972
- Rapid evolution in tech performance
- Rapid evolution in clinical applications
- Initial scan took 5 minutes (generation 1): now there are sub-
second acquisitions
- Increased speed of acquisition
- Better image quality
- Highly reliable info
- Exam tolerated by patients
However... -
correct answer ✅- CT has high doses
- High absorbed dose in tissues- organs might be irradiated that are
not part of the exam
, CT Dosimetry Exam Actual Questions
and Answers 2026
- Incident radiation up to 360 degree rotation
- Superficial tissue like breasts can receive high doses
- Short acquisition times do not mean low doses
- Relatively high effective doses
- More radiation to sensitive organs
- Procedure can be repeated several times
- Non contrast vs contrast - patients might have to have more than
1 scan
- Shorter scanning time does not mean less radiation dose because
we would increase the mAs = more radiation
CT Dose Quantities -
correct answer ✅- CTDI: Computed tomography dose index
- CTDI100: with a 100mm ionisation chamber
- CTDIW: weighted
- CTDI Vol: volume (used in spiral/helical)
- Dose Length Product
