Abstract: | Large errors can occur with time gain compensation which is set up manually. These errors occur since basic time gain compensation usually assumes that the tissues being scanned are uniform. Automatic gain control has been somewhat neglected, probably due to a lack of clinical confirmation of its value and reliability. The trial of a commercial automatic gain control system in routine abdominal work has demonstrated that for 90% of patients it is capable of producing images as good as, or better than, the basic gain controls while involving the operator in fewer control manipulations. |