Removal of tissue

• US 5,222,959 A
• Filed: 07/17/1990
• Issued: 06/29/1993
• Est. Priority Date: 07/17/1990
• Status: Expired due to Term

• Current Assignee: Alcon Incorporated
• Original Assignee: Aziz Y. Anis
• Inventors: Anis, Aziz Y.
• Primary Examiner(s): Pellegrino, Stephen C.
• Assistant Examiner(s): NOT, DEFINED
• Application Number:
  US07/553,975
• Time in Patent Office: 1,078 Days
• Field of Search: 604/22, 606/107, 606/159, 606/167, 606/180
• US Class Current: 606/107
• CPC Class Codes: A61B 2017/22008 used or promoted
• CPC Class Codes: A61F 9/00745 using mechanical vibrations, e.g. ultrasonic
• CPC Class Codes: A61F 9/00763 with rotating or reciprocating cutting elements, e.g. concentric cutting needles atherectomy cutting instruments A61B17/3207; endoscopic cutting instruments A61B17/320016

Abstract

To reduce damage to surrounding tissue while fragmenting some tissue such as for example not damaging the capsular wall while removing the lens during cataract removal surgery or not damaging artery or vein walls during bypass surgery while freeing the artery or vein to be transplanted, an incision is made for the insertion of surface-discriminating fragmenting handpiece. The surface-discriminating fragmenting handpiece fragments and permits aspiration of the tissue without damaging the surrounding wall by moving surfaces which permit the diseased tissue to fall within their cutting zone but which move at a rate of speed and have openings between them of such a size that the more integrated and smoother tissue does not fall within their cutting zone.

Claims

1. A method comprising the steps of:

inserting a surface discriminating fragmenting tip through small opening in the eye into the lens of an eye wherein the tip has movable spaced apart cutting surfaces;

moving the cutting surfaces at a rate high enough so that smooth healthy tissue does not move into the space between cutting edges but slow enough so that rougher tissue containing projections are moved into a cutting zone;

whereby the rougher tissue is pulverized;

aspirating the pulverized material;

making a small incision in the capsular sac along the margin to make the small opening;

the step of moving the cutting surfaces including the step of inserting a fragmenting tip and rotating the fragmenting tip to fragment a cataract;

retracting the cutting surfaces of said fragmenting tip when inserting the fragmenting tip;

releasing said cutting surfaces when the fragmenting tip is inside the capsular sac; and

retracting said cutting surfaces when removing the fragmenting tip, whereby a small incision may be used.

2. A method comprising the steps of:

making a small incision in the capsular sac of an eye along the margin to make a small opening;

inserting a surface discriminating fragmenting tip through the small opening in proximity with the lens of the eye, wherein the surface discriminating fragmenting tip has two movable spaced-apart elongated cutting blades, curved inwardly from a first diameter to a second smaller diameter at the tip and having an open space at the tip with the small diameter;

rotating the movable spaced-apart cutting surfaces with the cutting edges of the blades positioned to contact a lens and a capsular wall of the capsular sac without being constrained by opposed shear forces of edges of the surface discriminating fragmenting tip;

adjusting the rate of rotation of the cutting blades to a rate that fragments cortex that has a modulus sufficiently high to prevent the portion swept by the edge to move away from the path of cutting edges of the cutting blades and not the capsular wall that has a modulus of elasticity sufficiently low to permit the capsular wall to move from the path of the edge and avoid fragmenting wherein the fragmenting is only caused by the cutting blades without the aid of shear forces between an edge of the blade and another portion of the surface discriminating tip;

aspirating the pulverized material; and

introducing irrigating fluid into the capsular sac.

3. A method in accordance with claim 2 in which the step of rotating the movable spaced-apart cutting surfaces comprises the step of rotating the movable spaced-apart cutting surfaces with the tubular portion at a rate so that the cutting surfaces sweep across the smooth healthy tissue once during a time period of between 75 microseconds and 25 milliseconds.