COMPUTED TOMOGRAPHY MCQ
BY: BALBARADA, ZHANE A.
1. Which imaging modality eliminates superimposed structures for better anatomical differentiation?
A) Conventional Radiography
B) MRI
C) Computed Tomography (CT)
D) Ultrasound
Correct Answer: C – Computed Tomography (CT)
2. What does the term "tomography" mean, derived from the Greek word "tomos"?
A) Radiation
B) Section
C) Density
D) Rotation
Correct Answer: B – Section
3. Who is credited with inventing the first commercial CT scanner?
A) Wilhelm Roentgen
B) Godfrey Hounsfield
C) Marie Curie
D) Paul Lauterbur
Correct Answer: B – Godfrey Hounsfield
4. What principle developed in 1917 contributed to CT technology?
A) Fourier Transform
B) Radon Transform
C) Gaussian Theorem
D) Newton’s Law
Correct Answer: B – Radon Transform
5. What was the first commercially available CT scanner called?
A) EMI Scan
B) CAT Scanner
C) Radon Machine
D) Nuclear Scanner
Correct Answer: A – EMI Scan
6. Which mathematical technique is used to reconstruct CT images?
A) Gaussian Distribution
B) Algebraic Reconstruction Technique
C) Quantum Mechanics
D) Linear Regression
Correct Answer: B – Algebraic Reconstruction Technique
7. What scanning method allows continuous acquisition scanning?
A) Step-and-shoot scanning
B) Helical scanning
C) X-ray fluoroscopy
D) Ultrasound scanning
Correct Answer: B – Helical scanning
8. What is the main advantage of CT over conventional radiography?
A) Lower radiation exposure
B) Higher contrast resolution
C) Reduced cost
D) Real-time imaging
Correct Answer: B – Higher contrast resolution
9. In CT imaging, what determines slice thickness?
A) Y-axis localization
B) Z-axis localization
C) X-ray tube voltage
D) Detector array sensitivity
Correct Answer: B – Z-axis localization
10. What major company funded the development of CT technology using profits from The Beatles' albums?
A) Sony
B) EMI
C) Philips
D) Siemens
Correct Answer: B – EMI
11. What is the purpose of a bowtie filter in CT imaging?
A) Enhance radiation exposure
B) Shape X-ray intensity based on body thickness
C) Improve motion blur
D) Reduce noise artifacts
Correct Answer: B – Shape X-ray intensity based on body thickness
12. What does the CT number represent?
A) X-ray beam intensity
B) Density of tissues in Hounsfield Units (HU)
C) Patient positioning accuracy
D) Contrast resolution sensitivity
Correct Answer: B – Density of tissues in Hounsfield Units (HU)
13. What does the acronym "CAT" originally stand for?
A) Computed Axial Tomography
B) Computer-Assisted Tomography
C) Clinical Anatomical Testing
D) Conventional Anatomical Tomography
Correct Answer: A – Computed Axial Tomography
14. What device converts raw X-ray data into digital CT images?
A) Collimator
B) Data Acquisition System (DAS)
C) Lead shield
D) Ultrasound probe
Correct Answer: B – Data Acquisition System (DAS)
15. What scanning technique improves image quality by reducing motion artifacts?
A) Step-and-shoot method
B) Slip-ring technology
C) Projection-based X-ray imaging
D) Gamma camera scanning
Correct Answer: B – Slip-ring technology
16. What term refers to the relationship between X-ray attenuation and tissue density?
A) Spatial resolution
B) Contrast resolution
C) Linearity
D) Temporal resolution
Correct Answer: C – Linearity
17. Which component controls slice thickness in multi-slice CT?
A) X-ray tube power
B) Detector width
C) Rotation speed
D) Beam collimation
Correct Answer: B – Detector width
18. What scanning technique allows a single breath-hold examination?
A) Static imaging
B) Helical CT scanning
C) Gamma camera scanning
D) Conventional step-and-shoot scanning
Correct Answer: B – Helical CT scanning
19. Which scientist developed the first whole-body CT scanner in 1974?
A) Wilhelm Roentgen
B) Robert Ledley
C) Marie Curie
D) Allan Cormack
Correct Answer: B – Robert Ledley
20. What image processing method enhances CT contrast resolution?
A) Magnetic resonance imaging
B) Iterative reconstruction algorithms
C) Ultrasound wave interpretation
D) Linear regression smoothing
Correct Answer: B – Iterative reconstruction algorithms
21. What component in CT scanning converts X-ray photons into electrical signals?
A) Collimator
B) Photomultiplier tube
C) Detector array
D) Lead shield
Correct Answer: C – Detector array
22. Which term refers to the ability of a CT system to distinguish objects with similar densities?
A) Spatial resolution
B) Contrast resolution
C) Linearity
D) Temporal resolution
Correct Answer: B – Contrast resolution
23. What mathematical technique corrects for blurring in CT image reconstruction?
A) Radon transform
B) Gaussian smoothing
C) Filtered back projection
D) Neural network analysis
Correct Answer: C – Filtered back projection
24. What scanning method uses multiple rows of detectors to improve coverage?
A) Step-and-shoot scanning
B) Multidetector-row CT (MDCT)
C) Gamma-ray imaging
D) Ultrasound scanning
Correct Answer: B – Multidetector-row CT (MDCT)
25. Which of the following affects spatial resolution in CT imaging?
A) X-ray tube voltage
B) Detector size
C) Use of contrast agent
D) Patient positioning
Correct Answer: B – Detector size
26. What historical event led to EMI funding the development of CT scanners?
A) Moon landing
B) Success of The Beatles' albums
C) Discovery of X-rays
D) Cold War nuclear research
Correct Answer: B – Success of The Beatles' albums
27. What term describes the process of adjusting CT gray-scale intensity for better visualization?
A) Windowing
B) Beam hardening
C) Scatter correction
D) Quantum filtering
Correct Answer: A – Windowing
28. Which scanning method eliminates inter-scan delays using slip rings?
A) Step-and-shoot scanning
B) Conventional CT
C) Spiral CT
D) Ultrasound imaging
Correct Answer: C – Spiral CT
29. What does pitch refer to in spiral CT?
A) X-ray tube power output
B) Table movement relative to slice thickness
C) Image contrast ratio
D) X-ray photon energy levels
Correct Answer: B – Table movement relative to slice thickness
30. What measurement determines the size of a pixel in CT imaging?
A) Field of View (FOV) divided by matrix size
B) Window level adjustment
C) X-ray tube voltage
D) Contrast media absorption rate
Correct Answer: A – Field of View (FOV) divided by matrix size
31. What type of filter improves soft tissue contrast in CT imaging?
A) Soft tissue kernel filter
B) Hard X-ray filter
C) High-voltage smoothing filter
D) Gamma-ray suppression filter
Correct Answer: A – Soft tissue kernel filter
32. What CT scan feature helps ensure precise patient alignment before imaging?
A) Windowing
B) Scanogram
C) Image annotation
D) Ring artifact correction
Correct Answer: B – Scanogram
33. What major CT advantage allows for better visualization of soft tissue?
A) Increased spatial resolution
B) Enhanced contrast resolution
C) Lower radiation exposure
D) Real-time imaging
Correct Answer: B – Enhanced contrast resolution
34. What CT detector type is known for high sensitivity and faster response times?
A) Gas-filled detector
B) Solid-state scintillation detector
C) Gamma-ray detector
D) Lead shield detector
Correct Answer: B – Solid-state scintillation detector
35. What artifact occurs due to detector calibration errors in third-generation scanners?
A) Motion blur
B) Ring artifact
C) Beam hardening
D) Partial volume effect
Correct Answer: B – Ring artifact
36. What is a common scanning mode used in CT technology?
A) Fan-beam geometry
B) Step-and-shoot scanning
C) Cone-beam geometry
D) Parallel-beam geometry
Correct Answer: B – Step-and-shoot scanning
37. What CT hardware ensures continuous gantry rotation without cable entanglement?
A) Collimator
B) Slip rings
C) Linear encoder
D) Digital transformer
Correct Answer: B – Slip rings
38. What principle does filtered back projection aim to correct in CT imaging?
A) Scatter noise
B) Motion blur
C) Star-like artifacts
D) Low contrast resolution
Correct Answer: C – Star-like artifacts
39. Which CT scan generation introduced slip-ring technology?
A) First-generation
B) Third-generation
C) Fourth-generation
D) Fifth-generation
Correct Answer: C – Fourth-generation
40. What scanning method provides continuous X-ray emission without reversing gantry movement?
A) Step-and-shoot scanning
B) Spiral CT scanning
C) Gamma-ray emission imaging
D) Ultrasound-based imaging
Correct Answer: B – Spiral CT scanning
41. What advantage does multi-slice CT (MSCT) offer compared to conventional CT?
A) Lower spatial resolution
B) Faster scanning times
C) Reduced radiation exposure
D) Limited tissue differentiation
Correct Answer: B – Faster scanning times
42. Which imaging characteristic is quantified using Hounsfield units (HU)?
A) Spatial resolution
B) Contrast resolution
C) Tissue attenuation
D) Image noise
Correct Answer: C – Tissue attenuation
43. What function does collimation serve in CT scanning?
A) Focus X-ray beams onto a detector array
B) Eliminate scattered radiation
C) Control X-ray beam width
D) Enhance soft tissue contrast
Correct Answer: C – Control X-ray beam width
44. What is the primary component responsible for acquiring raw X-ray data in CT?
A) Photomultiplier tube
B) Collimator
C) Detector assembly
D) X-ray shield
Correct Answer: C – Detector assembly
45. What factor influences contrast resolution in CT imaging?
A) Use of lower kVp settings
B) Increased pitch ratio
C) Scanner gantry rotation speed
D) Detector array curvature
Correct Answer: A – Use of lower kVp settings
46. What is the primary function of the slip ring in CT scanning?
A) Reducing image contrast
B) Enabling continuous gantry rotation
C) Filtering low-energy X-rays
D) Adjusting spatial resolution
Correct Answer: B – Enabling continuous gantry rotation
47. What CT artifact results from beam attenuation differences across dense structures?
A) Partial volume effect
B) Beam hardening
C) Motion blur
D) Scatter radiation
Correct Answer: B – Beam hardening
48. What component minimizes scatter radiation effects in CT imaging?
A) Lead shielding
B) Bowtie filter
C) X-ray collimation
D) Image annotation
Correct Answer: B – Bowtie filter
49. What term describes the ratio of table movement to slice thickness in spiral CT?
A) Pitch
B) Beam attenuation
C) Detector absorption
D) Contrast ratio
Correct Answer: A – Pitch
50. Which scanning method was first introduced in fourth-generation CT systems?
A) Translate-rotate motion
B) Stationary detector ring
C) Gas-filled detector arrays
D) Parallel-beam geometry
Correct Answer: B – Stationary detector ring
51. What unit is used to measure X-ray attenuation in CT imaging?
A) Gauss
B) Tesla
C) Hounsfield Unit (HU)
D) Radon Value
Correct Answer: C – Hounsfield Unit (HU)
52. What imaging technique allows for 3D visualization of CT scan data?
A) Maximum Intensity Projection (MIP)
B) Simple back projection
C) Gamma-ray reflection imaging
D) Linear regression analysis
Correct Answer: A – Maximum Intensity Projection (MIP)
53. What term describes image blurring caused by inconsistent detector calibration?
A) Motion artifacts
B) Ring artifacts
C) Beam divergence
D) Spatial misalignment
Correct Answer: B – Ring artifacts
54. Which component helps prevent excessive heating in CT X-ray tubes?
A) Rotating anode
B) High-voltage generator
C) Pulse height analyzer
D) Detector assembly
Correct Answer: A – Rotating anode
55. What feature of solid-state detectors improves image acquisition efficiency?
A) High photon absorption
B) Slow response times
C) Narrow X-ray beam collimation
D) Low contrast resolution
Correct Answer: A – High photon absorption
56. Which CT reconstruction technique eliminates streak artifacts?
A) Neural network processing
B) Filtered back projection
C) Linear smoothing
D) Beam hardening correction
Correct Answer: B – Filtered back projection
57. What quality control parameter ensures uniform tissue attenuation measurements?
A) Noise suppression
B) Linearity
C) Detector recalibration
D) Contrast optimization
Correct Answer: B – Linearity
58. What scanning method provides continuous data acquisition during patient movement?
A) Step-and-shoot CT
B) Helical CT
C) Ultrasound CT
D) Gamma-ray tomography
Correct Answer: B – Helical CT
59. Which system component reduces X-ray exposure to the patient?
A) Lead shielding
B) Bowtie filter
C) Collimator
D) Contrast agent
Correct Answer: B – Bowtie filter
60. What innovation in third-generation CT scanners significantly improved scan speed?
A) Fan-beam geometry
B) Slip-ring technology
C) Stationary detector ring
D) Gas-filled detector arrays
Correct Answer: A – Fan-beam geometry
61. What feature of multi-slice CT improves patient throughput?
A) Faster scan duration
B) Reduced tissue resolution
C) Increased scatter radiation
D) Lower detector sensitivity
Correct Answer: A – Faster scan duration
62. What principle allows CT scanners to measure tissue densities?
A) X-ray attenuation
B) Gamma-ray fluorescence
C) Ultrasound reflection
D) Magnetic field resonance
Correct Answer: A – X-ray attenuation
63. What imaging technique reduces motion artifacts in cardiac scanning?
A) Electron Beam CT (EBCT)
B) Magnetic resonance imaging
C) Ultrasound tomography
D) Parallel-beam scanning
Correct Answer: A – Electron Beam CT (EBCT)
64. What type of resolution refers to the ability to differentiate objects of similar densities?
A) Spatial resolution
B) Contrast resolution
C) Temporal resolution
D) Image uniformity
Correct Answer: B – Contrast resolution
65. What CT image processing method enhances visibility of bone structures?
A) High-pass filtering
B) Spatial resolution adjustment
C) Bone window setting
D) Detector array expansion
Correct Answer: C – Bone window setting
66. What defines temporal resolution in CT imaging?
A) The speed at which scan data is acquired
B) The differentiation of tissues with similar densities
C) The ability to reconstruct images with fewer artifacts
D) The arrangement of detector rows
Correct Answer: A – The speed at which scan data is acquired
67. What innovation allowed modern CT scanners to reconstruct images almost instantly?
A) Array processors
B) Low-energy X-ray filtering
C) Parallel detector scanning
D) Gas-filled detector arrays
Correct Answer: A – Array processors
68. What CT scanning approach captures images in different planes beyond axial slices?
A) Multiplanar reconstruction (MPR)
B) Gamma-ray fluorescence analysis
C) Electron beam CT scanning
D) Parallel projection mapping
Correct Answer: A – Multiplanar reconstruction (MPR)
69. Which generation of CT scanners introduced multiple detector rows?
A) Fourth-generation
B) Fifth-generation
C) Sixth-generation
D) Seventh-generation
Correct Answer: D – Seventh-generation
70. What CT scanning method enables precise visualization of arteries?
A) CT angiography
B) Cone-beam tomography
C) Step-and-shoot imaging
D) X-ray contrast suppression
Correct Answer: A – CT angiography
71. What component helps reduce scatter radiation in CT imaging?
A) Bowtie filter
B) Collimator
C) Lead shielding
D) High-frequency generator
Correct Answer: B – Collimator
72. What factor determines the sharpness of a CT image?
A) Spatial resolution
B) Temporal resolution
C) Contrast resolution
D) Scan field of view
Correct Answer: A – Spatial resolution
73. Which term describes unwanted distortions in CT images?
A) Artifacts
B) Pixel density variations
C) Hounsfield calibration errors
D) Beam divergence
Correct Answer: A – Artifacts
74. What software correction reduces ring artifacts?
A) Image processing algorithm
B) Filtered back projection
C) Contrast enhancement
D) Pixel interpolation mapping
Correct Answer: A – Image processing algorithm
75. What component defines the brightness and contrast of CT images?
A) Window level
B) Spatial resolution settings
C) X-ray filtration
D) Detector calibration
Correct Answer: A – Window level
76. What artifact occurs when two tissues with similar densities overlap?
A) Partial volume artifact
B) Beam hardening artifact
C) Motion blur
D) Image distortion
Correct Answer: A – Partial volume artifact
77. What feature ensures accurate contrast enhancement in CT scans?
A) Optimal window width
B) High-energy X-ray filtering
C) Gantry speed control
D) Gamma-ray suppression
Correct Answer: A – Optimal window width
78. What technology ensures CT imaging clarity in obese patients?
A) Adaptive filtering algorithms
B) Bowtie filter adjustments
C) Enhanced collimation
D) X-ray dose modulation
Correct Answer: D – X-ray dose modulation
79. What is another term for a scanogram in CT imaging?
A) Calibration scan
B) Pilot scan
C) Contrast scan
D) Fluoroscopic scan
Correct Answer: B – Pilot scan
80. What factor affects the resolution of a scanogram in CT imaging?
A) Tube voltage and contrast level
B) Scan speed and exposure output
C) Detector sensitivity and collimator width
D) Image matrix and pixel intensity
Correct Answer: B – Scan speed and exposure output
81. What is the primary role of grid application in CT imaging?
A) Adjust contrast resolution
B) Confirm exact centering of the patient
C) Reduce scatter radiation
D) Minimize artifacts in reconstruction
Correct Answer: B – Confirm exact centering of the patient
82. What feature in CT allows an area of interest to be outlined?
A) Suppression
B) Cursor
C) Histogram
D) Reverse display
Correct Answer: B – Cursor
83. Which function in CT imaging permits the removal of surgical clip interference?
A) Image annotation
B) Grid alignment
C) Suppression
D) Window leveling
Correct Answer: C – Suppression
84. What imaging technique helps determine tissue density distributions?
A) Spatial resolution mapping
B) Histogram analysis
C) Multi-planar reconstruction
D) X-ray contrast enhancement
Correct Answer: B – Histogram analysis
85. What is the primary advantage of spiral CT imaging?
A) Reduces radiation exposure
B) Images larger tissue volumes in a single breath-hold
C) Requires less contrast agent
D) Eliminates the need for collimation
Correct Answer: B – Images larger tissue volumes in a single breath-hold
86. What is another term for Scan Field of View (SFOV)?
A) Calibration Field of View
B) Image Processing Field
C) Contrast Adjustment Field
D) Detector Input Field
Correct Answer: A – Calibration Field of View
87. What issue arises when parts of the patient extend beyond the SFOV?
A) Spatial resolution loss
B) Motion blur
C) Out-of-field artifacts
D) Detector saturation
Correct Answer: C – Out-of-field artifacts
88. What is another term for Display Field of View (DFOV)?
A) Pixel Density Ratio
B) Target or Zoom Field
C) Reconstruction Model
D) Contrast Enhancement Zone
Correct Answer: B – Target or Zoom Field
89. What function does an interpolation algorithm perform in CT scanning?
A) Enhances scan speed
B) Reconstructs an image at any z-axis position
C) Determines contrast resolution
D) Aligns scan projections
Correct Answer: B – Reconstructs an image at any z-axis position
90. What interpolation algorithm was first used in spiral CT reconstruction?
A) 180-degree interpolation
B) Gaussian smoothening
C) Linear regression filtering
D) 360-degree linear interpolation
Correct Answer: D – 360-degree linear interpolation
91. What is the disadvantage of 180-degree interpolation in spiral CT?
A) Increased image noise
B) Lower contrast resolution
C) Poor sagittal and coronal reconstruction
D) Increased motion artifacts
Correct Answer: A – Increased image noise
92. What effect does a pitch greater than 2.0 have on CT imaging?
A) Poor z-axis resolution
B) Reduced spatial resolution
C) Increased contrast accuracy
D) High radiation absorption
Correct Answer: A – Poor z-axis resolution
93. What happens when pitch is increased beyond optimal levels?
A) Overlapping images and higher radiation dose
B) Decreased spatial resolution and lower scan efficiency
C) Reduced patient exposure and improved contrast resolution
D) Enhanced structural detail but higher processing delays
Correct Answer: A – Overlapping images and higher radiation dose
94. What material is used as slip ring brush components?
A) Carbon fiber
B) Silver graphite alloy
C) Aluminum oxide
D) Tungsten carbide
Correct Answer: B – Silver graphite alloy
95. What scan modification helps reduce heat buildup in spiral CT tubes?
A) Lowering tube voltage
B) Using two focal spots
C) Increasing collimator width
D) Reducing scan field size
Correct Answer: B – Using two focal spots
96. What component ensures high heat capacity in spiral CT x-ray tubes?
A) Thermal cooling fans
B) Increased slip ring conductivity
C) High-power voltage generators
D) 8 MHU heat capacity systems
Correct Answer: D – 8 MHU heat capacity systems
97. What effect does low pitch have on spiral CT scanning?
A) Extended imaging and reduced patient dose
B) Poor contrast resolution and high image noise
C) Faster scan acquisition with increased motion artifacts
D) Overlapping images and improper reconstruction
Correct Answer: A – Extended imaging and reduced patient dose
98. What CT feature ensures contrast filling observations in vascular studies?
A) Dynamic scanning
B) Filtered back projection
C) Beam hardening correction
D) Out-of-field artifact suppression
Correct Answer: A – Dynamic scanning
99. What CT feature provides depth to a 3D reconstructed image?
A) Shaded Volume Display (SVD)
B) Step-and-shoot analysis
C) Gamma-ray suppression mapping
D) Contrast ratio realignment
Correct Answer: A – Shaded Volume Display (SVD)
100. What defines transverse (y-axis) resolution in CT imaging?
A) Reconstruction matrix and field of view
B) Window width setting and contrast ratio
C) Patient positioning and exposure time
D) Table motion and scan projection speed
Correct Answer: A – Reconstruction matrix and field of view
