Abstract: A soft tissue biopsy device provided with a piston retraction mechanism designed as a pistol-grip handle for developing a suction chamber within a housing as the piston slides therein. The suction reaches the cannula tip as it is withdrawn, drawing tissue into a depression on an exposed stylet. When the piston retraction mechanism reaches a preset cam limit point, it automatically releases the piston, which is shot forward and restored to its position in the housing by vacuum-spring action. Thus, the cannula slides quickly over the stylet, cutting the tissue and retaining it in the depression. The entire procedure is performed by a single-handed operation. The inventive biopsy device is designed with a piston and housing which are relatively large in comparison to the cannula diameter. Thus, with initial retraction of the piston, a relatively large suction is developed in the cannula, drawing tissue therein and firmly seating it in the stylet depression.

Abstract: A biopsy syringe for removing a specimen from a subject includes a tubular housing having a long hollow needle and two pistons. The first piston carries a mandrel received in the hollow needle. The second piston defines a chamber between it and the first piston enabling the syringe to be pre-loaded with a vacuum which is manually controllable so as to permit the first piston to be actuated to a retracted position in a smooth and simple manner while holding the biopsy syringe.