What was the main advantage of using cone-beam spiral CT scanners in comparison to fan beam scanners?
Allow three-dimensional projection techniques as well as the development of reconstruction techniques operating in three dimensions.
B. The time taken to complete the scan was increased.
C. The elimination of the lateral movement of the tube-detector
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What is an average dose received by an adult patient undergoing one CT scan?
A. 50-100 of the radiation dose unit of measurement.
B. 2–5 of the radiation dose unit of measurement.
C. 500-1000 of the radiation dose unit of measurement.
During a CT scan, sections of the body are exposed to radiation. The effective dose is the sum of the doses for all organs, multiplied by the respective tissue weighting factors. The unit of measurement for an effective radiation dose is:
A. millisievert (mSv)
B. milligray (mGy)
C. milliCurie (mCi)
Filtered back projection improves the quality of the final image by:
A. increasing contrast.
B. reducing pixilation.
C. reducing blurring.
The CT number or Hounsfield unit represents:
A. the sum of the voxel attenuation along the radiation path.
B. the attenuation coefficient number.
C. the amount of X-ray radiation emitted.
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