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Intravenous digital subtraction angiography (IV-DSA) is a form of angiography which was first developed in the late 1970s. IV-DSA is a computer technique that compares an X-ray image of a region of the body before and after radiopaque iodine based dye has been injected intravenously into the body. Tissues and blood vessels on the first image ...
Digital radiography is a form of radiography that uses x-ray–sensitive plates to directly capture data during the patient examination, immediately transferring it to a computer system without the use of an intermediate cassette. [1]
The enhancement of the brightness compared to the unfocused output from the bomb is /, where is the efficiency of conversion from bomb X-rays to laser X-rays, and is the dispersion angle. [ 117 ] If a typical ICBM is 1 metre (3 ft 3 in) in diameter, at a distance of 1,000 kilometers (620 mi) represents a solid angle of 10 −12 steradian (sr).
In 1999, Time placed Shoe-Store X Rays on a list of the 100 worst ideas of the 20th century. [29] [30] A shoe-fitting fluoroscope appeared on a 2011 episode of the History series American Restoration. [31] Its radionuclide source was found to be so dangerous that it was removed and replaced with a static X-ray. [32]
The history of X-ray computed tomography (CT) dates back to at least 1917 with the mathematical theory of the Radon transform. [ 1 ] [ 2 ] In the early 1900s an Italian radiologist named Alessandro Vallebona invented tomography (named "stratigrafia") which used radiographic film to see a single slice of the body.
Digital imaging was developed in the 1960s and 1970s, largely to avoid the operational weaknesses of film cameras, for scientific and military missions including the KH-11 program. As digital technology became cheaper in later decades, it replaced the old film methods for many purposes.
An X-ray generator generally contains an X-ray tube to produce the X-rays. Possibly, radioisotopes can also be used to generate X-rays. [1]An X-ray tube is a simple vacuum tube that contains a cathode, which directs a stream of electrons into a vacuum, and an anode, which collects the electrons and is made of tungsten to evacuate the heat generated by the collision.
Lead is the most common shield against X-rays because of its high density (11,340 kg/m 3), stopping power, ease of installation and low cost. The maximum range of a high-energy photon such as an X-ray in matter is infinite; at every point in the matter traversed by the photon, there is a probability of interaction.