FREE Computed Tomography Knowledge Questions and An
Which parameter is controlled by the milliampere-seconds (mAs) setting in CT scanning?
The mAs setting controls the amount of radiation exposure delivered during a CT scan. It directly influences image noise and quality.
What is the term for the mathematical process used to convert raw projection data into cross-sectional images?
Reconstruction is the mathematical process that converts raw projection data acquired during a CT scan into cross-sectional images for interpretation.
Which factor contributes to the occurrence of motion artifacts in CT imaging?
Motion artifacts can occur if the patient moves during a CT scan, particularly in cases of fast scan times.
Which artifact appears as dark streaks in a CT image, often caused by dense structures like bones?
Streak artifacts appear as dark streaks in a CT image and are commonly caused by dense structures like bones, leading to inaccuracies in image representation.
What is the primary advantage of using a higher pitch value in helical CT scans?
A higher pitch value in helical CT scans results in faster table movement through the gantry, leading to reduced scan times.
What is the purpose of CT image post-processing?
CT image post-processing involves applying various techniques to enhance image quality, such as reducing noise, enhancing contrast, and creating 3D reconstructions.
Which material is used in CT phantoms to simulate human tissue?
Water is commonly used in CT phantoms to simulate human tissue density and attenuation characteristics.
What is the purpose of CT perfusion imaging?
CT perfusion imaging is used to assess tissue blood flow and perfusion, providing insights into organ function and potential abnormalities.
What is the purpose of the CT bowtie filter?
The CT bowtie filter is used to shape the X-ray beam to account for the varying attenuation through the patient's body, resulting in more uniform image quality.
What is the purpose of contrast bolus tracking in CT angiography?
Contrast bolus tracking involves using a region of interest to monitor the arrival of contrast agent in blood vessels, ensuring optimal image acquisition timing.
What is the purpose of the CT localizer (scout) scan?
The CT localizer scan is used to outline the specific region of the body that will be scanned in subsequent imaging, ensuring accurate coverage.
Which imaging modality is typically combined with CT to provide functional and metabolic information?
PET-CT combines the anatomical information from CT with the functional and metabolic information provided by PET imaging.
What is the role of the CT gantry in the imaging process?
The CT gantry contains the X-ray tube and detectors and rotates around the patient to acquire projection images from multiple angles.
What does the term "windowing" refer to in CT image analysis?
Windowing involves adjusting the display settings of CT images to optimize the visualization of specific tissue densities and structures.
Which term refers to the ability of a CT scanner to differentiate between objects with similar densities?
Contrast resolution is the ability of a CT scanner to distinguish between objects with similar densities, providing clear visualization of subtle differences.
What type of CT scan is often used for assessing coronary artery disease and cardiac anatomy?
Cardiac CT, often performed using a helical technique, is used to assess coronary artery disease, cardiac anatomy, and other heart-related conditions.