Computed tomography basic principles

14-4.
1. Tomography is an x-ray technique in which shadows of superimposed structures are blurred out by a moving x-ray tube.
What are the basic principles of image production during CT examination?
The images are made by converting electrical energy (moving electrons) into X-ray photons, passing the photons through an object, and then converting the measured photons back into electrons.
The number of X-rays that pass through the object is inversely proportional to the density of the object..
What is the basic method of tomography?
There are 2 basic types of tomography: linear and nonlinear.
In both techniques, the tube moves in one direction while the film cassette moves in the opposite direction, with both motions centered around a fulcrum..
What is the basic principle of computed tomography?
The term “computed tomography,” or CT, refers to a computerized x-ray imaging procedure in which a narrow beam of x-rays is aimed at a patient and quickly rotated around the body, producing signals that are processed by the machine's computer to generate cross-sectional images, or “slices.”.
What is the basic theory of tomography?
Computer Tomography – Principle of X-Ray Tomography
X-ray tomography uses the ability of X-ray radiation to penetrate objects.
On the way through an object, part of the impinging radiation is absorbed.
The longer the radiographic length of the object, the less radiation escapes from the opposite side..
Basic Principles
High density tissue (such as bone) absorbs the radiation to a greater degree, and a reduced amount is detected by the scanner on the opposite side of the body.Low density tissue (such as the lungs), absorbs the radiation to a lesser degree, and there is a greater signal detected by the scanner.
The fundamental principle behind computed tomography is to acquire multiple views of an object over a range of angular orientations.
By this means, additional dimensional data are obtained in comparison to conventional X-radiography, in which there is only one view.

CT uses ionizing radiation, or x-rays, coupled with an electronic detector array to record a pattern of densities and create an image of a “slice” or “cut” of tissue. The x-ray beam rotates around the object within the scanner such that multiple x-ray projections pass through the object (Fig 1). Fig.

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Computed tomography basic principles

What are the basic principles of image production during CT examination?

What is the basic method of tomography?

What is the basic principle of computed tomography?

What is the basic theory of tomography?

Basic Principles