Ultrasonic Aspiration-Biopsy Transducer

A specially designed ultrasonic aspiration-biopsy transducer (UABT) containing a central lumen was used as an aid in the aspiration of fluid-containing structures and the biopsy of solid tissue. Ultrasound provided an estimate of the subcutaneous depth of the tissues of interest, and, in the case of cystic masses, allowed an estimate of the volume of fluid present. When an aspirating needle was directed through the lumen into a cystic mass, an echo was recorded from the needle tip while in the fluid. With solid tissues, echoes arising from the needle tip-soft tissue interface were masked by the echoes recorded from tissue interfaces and thus were more difficult to identify.