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The Wayback Machine - https://web.archive.org/web/20160310172530/http://www.ct-scan-info.com/64slicect.html
64 slice CT
scan is a CT Scanner that is able to take more than one image or slice at a time when the x-ray beam makes one complete rotation around you.
A single slice or a non-multi-slice CT scanner takes only one slice or image as the X-ray beam makes a complete rotation around you.
A 64 slice CT scanner can take up to 64 slices or images in one rotation.
The more detectors a CT Scanner has, the more slices per rotation it is able to acquire. The number of slices per rotation is equal to the number of detectors the scanner has. If a CT scanner has 16 detectors, it is able to take 16 slices per rotation; if it has 64 detectors, it can acquire 64 slices of anatomy per rotation and so on.
A detector is the device that reads or detects the amount of x-ray that passes through the object being scanned.
The first multi-slice CT scanners were introduced in the early 1990s.
The original Elscint-Twin scanner, introduced in 1994, allowed acquisition of two images simultaneously through a dual detector array. The 4-slice scanner was introduced in 1998.
The addition of detectors to CT Scan meant that more anatomy could be visualized in a shorter amount of time and in greater detail. Arteries could now be seen because we could catch
contrast material
in an artery before it got quickly pumped out by rapid arterial flow. This adding of detectors to CT Scan opened up an area now called CTA or Computed Tomographic Angiography. (The study of arteries)
64 slice CT scan is now being used in the study of the arteries of the heart called coronary CTA or cardiac CTA.
The introduction of 64-slice cardiac CT allows nearly all patients to be scanned with very high resolution. High resolution allows visualization of the entire coronary tree with high accuracy and detail. Plaque and calcifications can be visualized and used to determine the extent of coronary disease.