United States Patent  [ii] Patent Number: 4,811,735
Nash et al.  Date of Patent: Mar. 14, 1989
 STONE DESTROYING CATHETER AND METHOD OF USE
 Inventors: John Nash, Downingtown; Mark Michels, Glen Mills, both of Pa.
 Assignee: Kensey Nash Corporation, Exton, Pa.
 Appl. No.: 79,610
 Filed: Jul. 30,1987
 Int. CI* A61B 17/00
 U.S. CI 128/305; 128/328;
 Field of Search 128/328, 305; 604/22
 References Cited
U.S. PATENT DOCUMENTS
3,831,585 8/1974 Brondy 128/328
4,002,169 1/1977 Cupler 604/22
4,509,517 4/1985 Zibelin 128/328
4,611,594 9/1986 Grayhack et al 128/328
4,679,558 7/1987 Kensey et al 128/328
4,712,547 12/1987 Bonnet 128/305
4,739,760 4/1988 Chin et al 604/22
FOREIGN PATENT DOCUMENTS
2933266 5/1981 Fed. Rep. of Germany 128/328
2945237 5/1981 Fed. Rep. of Germany 128/328
3522649 1/1986 Fed. Rep. of Germany 128/328
Primary Examiner—Albert W. Davis, Jr.
Attorney, Agent, or Firm—Caesar, Rivise, Bernstein,
Cohen & Pokotilow, Ltd.
Apparatus for disintegrating or otherwise destroying a stone, such as a gallstone, within the body of a living being. The apparatus comprises a small diameter catheter having a longitudinal axis and a working head located at the distal end thereof. The catheter is capable of being located at any position within the body so that the working head is adjacent the stone. The working head is arranged to be rotated at a high speed about the longitudinal axis of the catheter. The working head comprises at least one bladed member having an impacting surface thereon. The bladed member is arranged to move from a retracted position wherein its impacting surface is located adjacent the periphery of the catheter to an extended position wherein the impacting surface extend substantially beyond the periphery of the catheter when the working head is rotated. The impacting surface is arranged so that when it rotates in the extended position, it impacts the stone to disintegrate or otherwise destroy the stone. A shroud is provided about the distal end of the catheter to aid in directing the stone to the rotating blade while also projecting adjacent body tissue from being engaged by the rotating blade. The rotating blade creates a vortex tending to pull the stone into the blade.
33 Claims, 3 Drawing Sheets