Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
227 words
A valvulotome for surgically incising venous valves in situ in order to convert a vein into an arterial bypass, comprising a thin, elongated, flexible wire having distal and proximal ends and having a centrally located axis, a cutting head secured to the distal end of the wire for passing through the vein in either direction, said cutting head having a single, narrow arm in fixed relationship with the wire and extending laterally from said axis, said arm having a blade edge facing in the proximal direction and extending in a direction transverse to said axis, and said cutting head also having a blunt tip edge offset from said axis projecting in the distal direction and tapered edges continuously and smoothly connected between said tip edge and lateral edges adjacent to the ends of said blade edge, said tapered edges extending in opposite directions which are oblique relative to said axis and forming an acute angle with each other in a plane defined by said blade edge and by said axis when said wire is straight, said tip edge and said lateral edges all having radii of curvature shorter than the radii of the curvature of said tapered edges in said plane; whereby the cutting head tends to center in the vein and pass through a venous valve in either direction with ease and less chance for trauma.
Claim 2
Dependent Claim
227 words
A valvulotome for surgically incising venous valves in situ in order to convert a vein into an arterial bypass, comprising a thin, elongated, flexible wire having distal and proximal ends and having a centrally located axis, a cutting head secured to the distal end of the wire for passing through the vein in either direction, said cutting head having a single, narrow arm in fixed relationship with the wire and extending laterally from said axis, said arm having a blade edge facing in the proximal direction and extending in a direction transverse to said axis, and said cutting head also having a blunt tip edge offset from said axis projecting in the distal direction and tapered edges continuously and smoothly connected between said tip edge and lateral edges adjacent to the ends of said blade edge, said tapered edges extending in opposite directions which are oblique relative to said axis and forming an acute angle with each other in a plane defined by said blade edge and by said axis when said wire is straight, said tip edge and said lateral edges all having radii of curvature shorter than the radii of the curvature of said tapered edges in said plane; whereby the cutting head tends to center in the vein and pass through a venous valve in either direction with ease and less chance for trauma.
Claim 3
Dependent Claim
28 words
A valvulotome according to claim 1 in which the lengths of the radii of curvature of said tapered edges are such that said tapered edges are substantially straight.
Claim 4
Dependent Claim
46 words
A valvulotome according to claim 1 in which said head has a blunt element located adjacent to the end of said blade edge farthest from said axis, with at least a portion of said blunt element extending proximally relative to said end of the blade edge.
Claim 5
Dependent Claim
16 words
A valvulotome according to claim 1 in which said wire is composed of a Nickel-Titanium alloy.
Claim 6
Dependent Claim
21 words
A valvulotome according to claim 1 in which said wire is composed of a Nickel-Titanium alloy, and is coated with polytetrafluoroethylene.
Claim 7
Dependent Claim
38 words
A valvulotome according to claim 1 in which the maximum dimension of said head in the direction perpendicular to said plane is less than the maximum dimension of said head in the direction parallel to said blade edge.