Noise in ultrasonic imaging.

The feasibility of noise measurement in medical ultrasonic imaging has been studied and a theoretical evaluation of stochastic noise influence upon the perceived image has been undertaken. The influence of noise on a perceived image has been calculated by considering the light intensity perception characteristic of the human eye and it has been found taht the additive noise in the video signal pushes the small signals in the image towards the invisible (black) region. Impulse noise measurements of amplitude and time jitter have been set up using a standard water/CCl4 interface and pulse amplitude analysis to take into account the random nature of noise by distribution measurements.