Asked by: Marceli Thalhauser
medical health heart and cardiovascular diseases

What does Hounsfield mean?

Last Updated: 14th March, 2020

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Definition/Introduction
The Hounsfield unit (HU) is a relative quantitative measurement of radio density used by radiologists in the interpretation of computed tomography (CT) images. The absorption/attenuation coefficient of radiation within a tissue is used during CT reconstruction to produce a grayscale image.

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Hereof, what is Hounsfield unit in a CT scan?

Hounsfield units (HU) are a dimensionless unit universally used in computed tomography (CT) scanning to express CT numbers in a standardized and convenient form. Hounsfield units are obtained from a linear transformation of the measured attenuation coefficients 1.

Similarly, how big is a Hounsfield unit? Typical Hounsfield unit (HU) values are −20 to −150 HU for adipose tissue and 20 to 50 HU for kidney. If an adrenal mass is less than 0 HU on unenhanced CT, it is almost certainly a benign adenoma.

Just so, what is Hounsfield number in CT scan?

nzˌfiːld/, named after Sir Godfrey Hounsfield, is a quantitative scale for describing radiodensity. It is frequently used in CT scans, where its value is also termed CT number.

How are Hounsfield units calculated?

Hounsfield Unit formula:

  1. HU = Hounsfield Unit.
  2. μ = linear attenuation coefficient.
  3. X = tissue.

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