Robert C. Stevens has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
Abstract: Method and apparatus for opening a partially or totally occluded blood vessel. A conventional catheter is inserted within a patient and the condition of a blood vessel ascertained. If it is determined that sufficient blockage exists to cannulize the vessel, a small diameter drive catheter having a rotatable head at a distal end is inserted into the conventional catheter in close proximity to the occluded region. The head is rotated at high speeds as dye is injected through the catheter to monitor progress of the procedure. Different sized rotating heads having different blockage removing characteristics are inserted until the procedure has been completed to the physician's satisfaction. The drive mechanism is a small d.c. powered hand-held motor operated by the physician during the procedure.
Abstract: A flexible drive catheter for removing deposits from the inner walls of a blood vessel to increase blood flow through the vessel. The catheter includes an outer sheath and a rotatable core coupled to a distal tip which directly contacts the deposits. An outer surface of the rotatable core defines a screw pump for moving dislodged deposits away from the blood vessel through the catheter sheath to a bifurcating adapter located outside the patient. One opening in the adapter accommodates the rotatable core and a second opening provides a method of monitoring blood pressure in the blood vessel, removing dislodged deposits from the catheter and injecting flushing liquids or clotting control agents into the blood vessel.
Abstract: Guidewire insertion method and apparatus. A guidewire can be inserted into an obstructed blood vessel. A proximal portion of the guidewire is driven back and forth at high speed by a hand-held drive unit containing a battery, a D.C. motor and a transmission that converts rotating motor output shaft motion to reciprocating back and forth movement of a clamp that engages the guidewire. The guidewire moves back and forth at high speed within a catheter and a distal guidewire tip engages the obstruction with a ramming back and forth action to form a pilot passageway through the obstruction.
Abstract: A catheter guidewire for use in inserting a catheter into a subject. The guidewire includes a center wire core surrounded by a coiled wire sheath that is Teflon coated on an outside surface. The extreme distal end of the rod widens to a sphere. The rod and sheath are pre-bent to a desired form. As the core is rotated inside the sheath, the distal end of the guidewire is re-oriented in the direction of rotation.
Abstract: An improved technique for positioning a balloon dilatation catheter. When the balloon catheter approaches an obstruction that is difficult to enter, a drive catheter having a rotatable head is inserted into a central passageway in the catheter. The drive catheter bores through the obstruction allowing the balloon to be inserted and pressurized to compress obstructions and widen a passageway for blood flow.
Abstract: Disclosed is a urological catheter equipped, at its distal portion, with a pair of balloons inflatable from the proximal end of the catheter. One balloon completely covers the distal tip of the catheter to serve, when inflated, as a cushion preventing damage to the patient's bladder, while the other balloon serves to anchor the catheter in sealing relation to the discharge passage of the bladder. A drainage opening in the catheter wall is disposed intermediate the balloons.
Abstract: Hemostasis cannula comprising a body having a passage therethrough adapted to receive a catheter and a pair of juxtaposed gaskets mounted in the passage. The first gasket forms a seal around a catheter enclosed within the cannula; the second gasket is compressed against the first to seal the passage when the catheter is removed. The cannula also features a flexible entrance tube and a port for introducing fluids into a patient's blood vessel.
Abstract: A separatory device is disclosed wherein a bundle of hollow fibers have their end portions potted in a polyurethane tube-sheet, said polyurethane consisting of an isocyanate-containing prepolymer which is non-catalytically crosslinked with a polyol. The resulting tube-sheet has demonstrated an unexpected degree of adherence to the fibers. In addition, essentially no adverse toxicity effects are encountered in biomedical applications of said device.