Multislice computed tomography coronary angiography

Abstract

Computed Tomography (CT) imaging is also known as "CAT scanning" (Computed Axial Tomography). Tomography is from the Greek word "tomos" meaning "slice" or "section" and "graphia" meaning "describing". CT was invented in 1972 by British engineer Godfrey Hounsfield of EMI Laboratories, England, and independently by South Mrican born physicist Allan Cormack of Tufts University, Massachusetts.1 • 2 Hounsfield was later awarded the Nobel Peace Prize and honoured with Knighthood in England for his contributions to medicine and science. The first clinical CT scanners were installed between 1974 and 1976. The original systems were dedicated to head imaging only, but "whole body" systems with larger patient openings became available in 1976. CT became widely available by about 1980. There are now about 30.000 installed worldwide. The first CT scanner developed by Hounsfield in his lab at EMI took several hours to acquire the raw data for a single scan or "slice" and took days to reconstruct a single image from this raw data. The latest multislice CT systems can collect up to 64 slices of data in one rotation of about 333ms and reconstruct up to 20 slicesjs with a 512x512-matrix. During its 25-year history, CT has made great improvements in speed, patient comfort, and resolution. As CT scan times have gotten faster, more anatomy can be scanned in less time. Faster scanning helps to eliminate artefacts from patient motion such as breathing or peristalsis. Computed tomography (CT) has been regarded in the late '80 and '90 as the "workhorse" of radiological routine, the minor sister of the more "fashionable" Magnetic Resonance (MRI). Actually, CT was bom and remains a mono-parametric technique when compared with MRI that is multi-parametric.