Computed Tomography Test Cheat Sheet 2026

The 30 highest-yield Computed Tomography Test facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. What is the primary shielding material used in CT scanning room walls? → Lead or lead-equivalent concrete
2. The term 'Z-axis dose profile' in CT refers to dose distribution along which direction? → Patient cranio-caudal (head-to-foot) axis
3. Which detector material is most commonly used in modern solid-state CT detectors? → Gadolinium oxysulfide (GOS)
4. What is the function of the analog-to-digital converter (ADC) in a CT system? → To convert the electrical detector signal into digital data for processing
5. What is the most appropriate CT protocol to evaluate a patient presenting with acute stroke within the therapeutic window? → Non-contrast CT brain followed by CT perfusion and CT angiography
6. Which reconstruction algorithm provides the sharpest images but also the most noise in CT? → High-frequency (bone/edge) kernel
7. What procedure results in a more monochromatic beam and lowers patient radiation exposure by reducing the longest wavelength photons? → Filtration
8. On CT of the spine, which finding is most indicative of an acute compression fracture? → Loss of vertebral body height with band-like edema pattern on CT (marrow hyperdensity)
9. Which type of CT scan is specifically designed for imaging the coronary arteries and assessing heart health? → Cardiac CT
10. In CT imaging, what does the term "slice thickness" refer to? → The distance between adjacent slices
11. Which term describes the ability of a CT scanner to accurately represent small objects or structures in the images? → Spatial resolution
12. What effect does increasing CT tube voltage (kVp) have on patient dose? → Increases dose due to higher photon energy and greater beam penetration
13. Which component of a CT scanner is responsible for rotating the X-ray tube and detector around the patient? → Gantry
14. For what group have weight-based CT protocols with color-coding been established to help lower patient doses? → Pediatric
15. Which term refers to the ability of a CT scanner to differentiate between objects with similar densities? → Contrast resolution
16. Which factor most significantly increases a patient's risk for a severe contrast reaction? → History of a prior severe contrast reaction
17. Poor historian, his perplexity has grown over the past few weeks. What does the picture depict? → Bilateral subdural collections
18. On CT of the abdomen, the normal appendix should have a maximum diameter of: → Less than 6 mm
19. What does multiplanar reformation (MPR) allow clinicians to do with CT data? → View reconstructed images in coronal, sagittal, and oblique planes from axial data
20. At what injection rate (mL/sec) is intravenous contrast typically administered for a CT pulmonary angiography (CTPA)? → 3–5 mL/sec
21. What is the primary advantage of using a higher pitch value in helical CT scans? → Faster scan speed
22. What is the purpose of CT image post-processing? → To enhance image quality and visualization
23. What is the most common type of iodinated contrast media used for CT examinations? → Non-ionic, water-soluble iodinated contrast
24. What does the term "slice thickness" refer to in CT imaging? → The spacing between slices
25. What is the role of the post-patient anti-scatter grid in CT? → To block scattered radiation from reaching the detectors
26. What is the purpose of using a 'sharp' (bone) reconstruction kernel in CT? → To enhance edge detail and spatial resolution at the cost of increased noise
27. Dual-energy CT (DECT) can be used to create virtual non-contrast (VNC) images. What does this eliminate for the patient? → The need for a separate pre-contrast CT acquisition
28. What is the purpose of a CT scout image? → To measure bone density
29. Ring artifacts in CT are most commonly caused by which problem? → Defective or mis-calibrated detector elements
30. What technique is used to time the CT acquisition to arterial contrast peak in CT angiography? → Bolus tracking (SmartPrep) or test bolus technique