CT Module 1

Fourth generation scanners employed detectors that were: a. curved/nonrotating. b. linear/rotating. c. curved/rotating. d. linear/nonrotating.

a. curved/nonrotating.

Which of the following types of scanners used water bags? a. first generation only b. first and second generation c. first, second and third generation d. Water bags have never been used with CT scanning.

a. first generation only

First generation scanners were only capable of imaging the: a. head/brain. b. extremities. c. chest, abdomen and pelvis. d. A and B are correct.

a. head/brain.

Which of the following is the most effective type of CT detector? a. scintillation b. xenon gas c. linear array d. photodiode

a. scintillation

Nutating refers to the process of: a. tilting the detector ring. b. tilting the x-ray tube. c. tilting the gantry. d. translation.

a. tilting the detector ring.

Second generation scanning employed: a. a pencil beam/a single detector. b. a fan beam/multidetectors. c. more indexing (compared with first generation scanners) d. B and C are correct.

b. a fan beam/multidetectors.

Which of the following sources of radiation were used in Hounsfield's first primitive CT scanner? a. x-ray b. americium c. radium d. radon

b. americium

Beam-shaping filters are designed to: a. remove higher-energy photons from the beam. b. change the spatial distribution of the beam. c. decrease subject contrast. d. restrict the path of photons coming from the x-ray tube.

b. change the spatial distribution of the beam.

Which of the following x-ray beam geometries is used by modern, multidetector CT scanners? a. pencil beam b. cone beam c. fan beam d. pinpoint beam

b. cone beam

To achieve optimum detail and the thinnest slice possible, modern spiral-helical CT scanner x-ray tubes contain only one filament/focal spot. a. true b. false

b. false

First generation CT scanners used _____ beam scanning. a. cone b. pencil c. fan d. pinpoint

b. pencil

Which generation of CT scanners was the first to use a curved array of rotating detectors? a. second b. third c. fourth d. fifth

b. third

CT scanner x-ray tube voltages range from ______ to _____ kilovolts (kV). a. 60; 100 b. 80; 120 c. 80; 140 d. 100; 160

c. 80; 140

A CT gantry includes all of the following components except: a. collimators. b. detectors. c. central processing unit. d. bow tie filters.

c. central processing unit.

Which generation of CT scanners is associated with the term "EBCT" and the use of an electron beam gun? a. seventh b. sixth c. fifth d. fourth

c. fifth

Generators are often times located within the gantry. These types of generators are typically: a. full wave/three-phase. b. medium frequency. c. high frequency. d. multiwave/two-phase.

c. high frequency.

In sixth generation CT scanners, which of the following elements rotate around the patient? a. the x-ray tube b. detectors c. x-ray tube and detectors d. No choices are correct.

c. x-ray tube and detectors

The term "translation" is associated with _____ generation scanners. a. first b. second c. third d. A and B are correct.

d. A and B are correct.

Beam-shaping filters are generally composed of: a. aluminum. b. copper. c. teflon. d. A and C are correct.

d. A and C are correct.

Which of the following terms is associated with seventh generation spiral-helical technology? a. multisection scanner b. multidetector scanner c. multiple detector array scanner d. All choices are correct.

d. All choices are correct.

Spiral-helical CT scanning is based on: a. sequential data acquisition. b. slip-ring technology. c. volume data acquisition. d. B and C are correct.

d. B and C are correct.

The process related to the first computed tomography scanner was called: a. computer-assisted tomography. b. reconstructive tomography. c. Hounsfield tomography. d. computerized transverse axial scanning.

d. computerized transverse axial scanning.

When image data is acquired by a CT scanner, it goes through a process known as: a. convolution. b. photon flux. c. digitization. d. quantization.

d. quantization.

All power to the gantry of a spiral-helical CT scanner is conveyed via: a. high-tension cables. b. rotating wire brushes. c. photon flux. d. slip rings.

d. slip rings.

In multislice CT scanners, detector systems with equal-size detector elements are called _____ arrays. a. linear b. curved c. adaptive d. symmetric

d. symmetric