Computed Tomography Test Computed Tomography (CT) 2

Question 1

What is the primary purpose of a CT gantry tilt?

Accepted Answer

To align the scan plane with anatomical structures while avoiding radiation-sensitive organs

Answer

Gantry tilt allows the scan plane to be angled relative to the patient's body axis to align with anatomy or minimize dose to sensitive structures like the lens of the eye.

Question 2

Which CT image reconstruction algorithm produces the sharpest edges but introduces the most noise?

Accepted Answer

Bone (sharp) kernel

Answer

Bone or high-frequency kernels enhance edge detail for structures like cortical bone but amplify image noise compared to smooth kernels.

Question 3

In CT angiography, what timing method uses real-time monitoring of contrast arrival in a target vessel?

Accepted Answer

Bolus tracking (SmartPrep/Care Bolus)

Answer

Bolus tracking monitors a region of interest in real time and automatically triggers scanning when contrast attenuation reaches a preset threshold.

Question 4

What does the term 'pitch' refer to in helical CT?

Accepted Answer

Table movement per rotation divided by total beam collimation

Answer

Pitch is defined as table feed per 360° gantry rotation divided by the total X-ray beam width (collimation), affecting coverage speed and dose.

Question 5

Which parameter most directly controls CT image noise?

Accepted Answer

mAs

Answer

mAs (milliampere-seconds) determines the quantity of X-ray photons produced; higher mAs means more photons, less quantum noise, and better image quality.

Computed Tomography Test Practice Test

Computed Tomography Test Practice Test

Computed Tomography Test Computed Tomography (CT) 2