Physics of Computed Tomography: Equipment

Abstract

Computed Tomography (CT) is a non-invasive imaging technique that utilizes X-ray technology to create detailed cross-sectional images of the body. The fundamental physics behind CT revolves around the use of X-rays to generate images, with advanced mathematical algorithms processing the data to construct high-resolution images. CT scanners consist of several key components, including an X-ray tube, detectors, and a computer system that processes and reconstructs the images. The X-ray tube emits X-rays that pass through the body, with different tissues attenuating the X-rays to varying degrees. Detectors measure the transmitted X-rays, and the data is sent to a computer that applies complex algorithms, such as filtered back projection or iterative reconstruction, to create the final image. The primary components of a CT scanner include the gantry, which houses the rotating X-ray tube and detectors; the computer workstation for image reconstruction and analysis; and the patient table that moves through the scanner. Key factors affecting CT image quality include radiation dose, slice thickness, detector technology, and scanning parameters like kVp and mAs. Advances in CT technology have led to innovations such as multi-detector CT (MDCT), which enables faster and more detailed imaging with reduced scan times and improved spatial resolution.