Intro to CT review

Which generation of CT scanners introduced a fan- shaped beam, where the detector array and the tube rotate around the patient to obtain information?

• 2nd

• 3rd

• 4th

• 5th

Which generation of scanners has stationary detectors located around the entire gantry and the tube rotates around the patient to obtain the image?

• 3rd

• 4th

• 5th

• 6th

What type of CT detector is most efficient because it can receive x-rays coming in from various angles?

• Xenon

• Solid State Crystal/ Scintillation

• ADC

• DAC

Radiographic tomography was invented in ____, and CT was invented in ____.

• 1921; 1971

• 1895; 1945

• 1970; 1979

• 1910; 1973

Name the collimator that stops scatter radiation from reaching the CT detector.

• pre-patient

• post- detector

• post- patient

• pre-collimator

How can the fulcrum be adjusted for tomography?

• Up and down from the level of the table

• Right and left of the table

• The fulcrum is not a moving piece of the table

What is the HU of water?

• 1,000

• 0

• -1,000

The HU of air is ____, and the HU of compact bone is ____.

• 1,000; -1,000

• -1,000; 1,000

• 0; 1,000

• 0, -1,000

What term describes the center of the HU values and defines the area of interest for that particular scan?

• window level

• window width

• window focal

• window pivot

What type of resolution is described as being able to distinguish between structures with similar densities?

• temporal

• spatial

• contrast

• differential