The CT exam creates images analogous to a single slice of bread from a whole loaf or a slice from an orange. (See Figure 2) Hence, the word “slice” is often used to describe a view of patient anatomy.
The quality of an image depends on the nature of the X-ray source and detectors, the number and speed of the measurements, the details of the reconstruction technique (algorithm), the machine characteristics and the methods of data display and interpretation. The computer allows healthcare professionals to shade, rotate, correlate and measure anatomy in the image.
This data can be manipulated to derive even more precise clinical information. While conventional X-ray can discern tissue density difference of 5 percent, CT can distinguish a density difference of 1 percent or less, aiding in diagnostic confidence.
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