Tube current modulation
Tube current modulation is a feature of modern CT scanners to alter the strength of the beam by modulating the current of the x-ray tube depending on the signal to noise ratio. The purpose of tube current modulation is to maintain a near constant signal to noise ratio in the image across different areas of the body with varying thicknesses in order to avoid excessive radiation doses whilst maintaining image quality. It is similar to the automatic exposure control used in film radiography.
- 1. Jerrold T. Bushberg, John M. Boone. The Essential Physics of Medical Imaging. (2011) ISBN: 9780781780575