History Of CT Scan ( Computed Tomography).
What is a CT scan ?
The Computed tomography scanner was invented by sir Godfrey N Hounsfield in 1972 and initially named as Computerized axial tomography (CAT). The first head CT scanner was introduced, CT has matured greatly. The first CT scanner, an EMI Mark 1, produced images with 80 X 80 pixel resolution (3-mm pixels), and each pair of slices required approximately 4.5 minutes of scan time and 1.5 minutes of reconstruction time. Because of the long acquisition times required for the early scanners and the constraints of cardiac and respiratory motion, it was originally thought that CT would be practical only for head scans.
CT is one of the many technologies that was made possible by the invention of the computer. The clinical potential of CT became obvious during its early clinical use and the excitement forever solidified the role of computers in medical imaging. Recent advances in acquisition geometry, detector technology, multiple detector arrays, and x-ray tube design have led to scan times now measured in fractions of a second. Modern computer deliver computational power that allows reconstruction of the image data essentially in real time.
The invention of the CT scanner earned Godfrey Hounsfield of Britain and Allan Cormack of the United States the Nobel Prize for Medicine in 1979. CT scanner technology today is used not only in medicine but in many other industrial applications, such as nondestructive testing and soil core analysis. Computed tomography (CT) is in its fourth decade of clinical use and has proved invaluable as a diagnostic tool for many clinical applications, from cancer diagnosis to trauma to osteoporosis screening.
In 1917, An Austrian mathematician J.Radon proved that two or three dimensional object could be reproduced. So the concept of CT scanner was established 55years before.
In 1956, Bracewell working in radioastronomy , constructed a solar map from ray projections. Oldendorfin 1961 and Cormack in 1963 understood the concept of computed tomography and built laboratory models.
In 1968, Kuhl and Edwards built a successful mechanical scaner for nuclear imaging but did not apply their work into diagnostic radiology. It remaintain for Hounsfield to put a CT system together and demonstrate its remarkable ability.