Basic Principles of Computed Tomography (CT)

These flashcards cover key terms and concepts from the lecture on the basic principles of Computed Tomography (CT), including definitions and explanations relevant to the understanding of CT technology.

Computed Tomography (CT)

A medical imaging technique that produces cross-sectional images of the body.

Beam Attenuation

The reduction in intensity of an X-ray beam as it passes through a material; correlates to grayscale in CT images.

Hounsfield Unit (HU)

A measurement scale for the density of materials in CT imaging, where water is 0, air is -1000, and dense bone is 1000.

Voxel

The three-dimensional equivalent of a pixel, representing a value in a 3D space in imaging.

Linear Attenuation Coefficient (LAC)

A measure of how easily a material can be penetrated by an X-ray beam, affecting image contrast.

Positive Contrast Agent

High-density substances like Barium Sulfate or Iodine used to enhance visualization in imaging studies.

Negative Contrast Agent

Low-density substances such as water that can help differentiate anatomical structures in imaging.

Polychromatic X-ray Beam

X-ray beams that contain multiple energy levels, which can result in image artifacts.

Volume Averaging

The phenomenon where the properties of a voxel reflect a mixture of tissues, affecting image accuracy.

Scan Modes

Techniques used in CT scanning, including step-and-shoot and helical (spiral) scanning.