Hounsfield unit (HU)

Hounsfield unit (HU) depends on the linear attenuation co-efficient.

Attenuation is the reduction of the intensity of an X-ray beam as it traverses matter. HU is used to measure the X-ray attenuation values in CT scanning, thus quantifying the radiodensity of the tissue.



The Hounsfield scale, named after Sir Godfrey Hounsfield invented CT in the year 1972 and was awarded Nobel Prize for Medicine in the year 1979.


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