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What is Hounsfield units used in? and explain in detail?
ANSWER: (A) CT scanREF: Sutton's Radiology 7th e p. 1724The Hounsfield scale, named after Sir Godfrey Newbold Hounsfield, is a quantitative scale for describing radiodensity.The Hounsfield unit (HU) scale is a linear transformation of the original linear attenuation coefficient measurement into one in which the radiodensity of distilled water at standard pressure and temperature (STP) is defined as zero Hounsfield units (HU), while the radiodensity of air at STP is defined as -1000 HUThe Hounsfield scale applies to medical grade CT scans but not to cone beam computed tomography (CBCT) scansSubstanceHUAir-1000Fat-120Water0Blood+30 to +45Muscle+40Contrast+130Bone+400 or more