Computed Tomography Test Study Guide 2026
Everything you need to pass the Computed Tomography Test exam in one place: the exam format, every topic to study, real practice questions with explanations, flashcards, and full-length practice tests. Free, no sign-up needed.
📋 Computed Tomography Test Exam Format at a Glance
📚 Computed Tomography Test Topics to Study (21)
✍️ Sample Computed Tomography Test Questions & Answers
1. Which regulatory body in the United States sets occupational radiation dose limits for CT technologists?
The NRC sets the annual occupational whole-body dose limit of 50 mSv (5 rem) for radiation workers in the US, including CT technologists.
2. Which artifact appears as dark streaks in a CT image, often caused by dense structures like bones?
Streak artifacts are characterized by dark lines or bands that appear across a CT image, often originating from highly attenuating objects. While beam hardening is a common cause of streaks, especially from dense bone, the general term for these linear obscurations is "streak artifact." Metallic objects also cause severe streak artifacts due to their high attenuation and beam hardening effects.
3. What does the term "windowing" refer to in CT image analysis?
Windowing in CT imaging refers to the process of adjusting the range of Hounsfield units (CT numbers) displayed on the monitor, which directly controls the brightness (window level) and contrast (window width) of the image. This allows radiologists to optimize the visualization of specific tissue types, such as bone, soft tissue, or lung, by highlighting their particular density ranges. It's a crucial post-processing technique for diagnostic interpretation.
4. In CT, increasing the field of view (FOV) while keeping matrix size constant will have what effect on voxel size?
Voxel size = FOV / matrix size; a larger FOV with the same matrix produces larger voxels, lowering spatial resolution.
5. Which parameter is adjusted by the kilovoltage (kV) setting in CT scanning?
The kilovoltage (kV) setting in CT scanning determines the energy and penetrating power of the X-ray beam. A higher kV setting means the X-rays are more energetic and penetrate tissues more effectively, but it also directly increases the amount of radiation absorbed by the patient. Therefore, kV is a primary parameter for adjusting the radiation dose.
6. What is the primary purpose of using automatic exposure control (AEC) in CT?
AEC (also called tube current modulation) automatically adjusts mA based on patient attenuation to optimize image quality while minimizing dose.