A glossary of terms and their definitions is appended. A. Gain and TGC Gain refers to amplification of the signal. Time gain compensation is a graduated adjustment of the amplitude of the signal at predetermined distances from the transducer, applied to balance intensity of the image, create even gain throughout the image, and compensate for attenuation in the far field.
Time gain compensation adjustments are specific only to certain mechanical scanners.
There is no standard for setting the levels of compression and rejection, therefore, operators should adjust the settings until an optimal image with smooth gradation of gray levels is obtained. Rejection and compression can easily be set too high or too low, resulting in image artifacts. Rejection and compression adjustments are specific only to certain mechanical scanners. This technique can introduce objectionable motion artifacts. D. Gamma Curves Gamma curves control the relationship between the actual and the displayed gray scale.