Patent attributes
The invention is directed to marker delivery devices and methods of using such devices. The delivery devices embodying features of the invention include a delivery cannula with a discharge opening and a releasable plug disposed in the inner lumen of the delivery cannula so as to at least partially occlude the discharge opening. The releasable plug prevents ingress of tissue, body fluids and the like into the bore of the tube, and prevents the premature discharge of any markers proximal to the releasable plug from passing through the discharge opening before the distal end of the cannula is properly positioned at a desired location within a patient's body. The releasable plug preferably has an MRI detectable element. Preferably, at least one remotely detectable marker mass is provided in the inner lumen of the cannula proximal to the releasable plug.
