What unit is Hu from?

Hu is the unit of heat capacity of light bulb in CT equipment. HU value is the unit of CT value, just as weight is measured in g or kg, HU value is also the unit of CT value. CT obtains black-and-white images of different brain tissues through different absorption of X-rays. The higher the CT value, that is, the higher the value in front of Hu, indicating that the higher the CT value, the whitish signal appears on CT. For example, in the case of bone calcification, the CT value of calcification is 90- 100HU, and the CT value is relatively high, showing white high-density changes on CT. Similarly, the CT values of cerebrospinal fluid and water are relatively low, and on CT, they are dark. So different brain tissues have different CT values. For example, in the case of bleeding, the CT value will be 20-30HU higher than that of normal brain tissue, and it can show white and high-density changes on CT. CT, or computed tomography, uses precisely collimated X-rays, gamma rays, ultrasonic waves, etc. And perform cross-sectional scanning around a specific part of the human body together with a high-sensitivity detector. It has the characteristics of fast scanning time and clear image, and can be used for the examination of many diseases. According to the different rays used, it can be divided into X-ray CT(X-CT) and γ-ray CT(γ-CT).