Abstract: An echographic suction cannula has an elongated suction tube with a closed front end and an open back end. Side openings are also provided for admitting therethrough material to be evacuated and discharged. An ultrasonic transducer is encased within the suction tube and partially exposed so as to be able to transmit and receive ultrasonic waves. An electrical cable extending longitudinally within the outer casing of the suction tube connects the transducer to an external circuit for controlling the operation of the transducer, causing pulse signals to be transmitted, receiving reflected signals and calculating the thickness of the layer of fatty tissues into which the front end of the cannula has been inserted.