Universal biopsy needle

Claim 2

A single cannula biopsy needle adapted for both end cutting and side cutting of a tissue specimen from a tissue mass, said biopsy needle comprising: a hollow thin wall cylindrical cannula of open ended configuration and having a center passage and a longitudinal axis, a distal end on said cannula forming a circumferentially opening and axially open ended continuous channel, said channel being defined by a frontal tip section and an intermediate cutting section, said frontal tip section having a frontal cutting edge lying in a plane forming a first acute angle with said longitudinal axis, said intermediate cutting section having first and second longitudinal cutting edges proximally contiguous with and forming proximal angled extensions of the said frontal cutting edge of said frontal tip section, said first and second longitudinal cutting edges being inclined with respect to said axis at a second acute angle lesser than said first acute angle, said frontal cutting edge of said frontal tip section being effective to axially incise a short length of tissue upon forward movement of the cannula along said longitudinal axis into a tissue mass and said first and second longitudinal cutting edges being effective to circumferentially sever the said incised tissue length from said tissue mass upon rotation of said cannula about said longitudinal axis.

Claim 3

The biopsy needle as recited in claim 1 wherein said first and second longitudinal cutting edges lie in a common plane.

Claim 4

The biopsy needle as recited in claim 2 wherein said common plane is coincident with said axis.

Claim 5

The biopsy needle as recited in claim 2 wherein said tip section is symmetrically disposed with respect to said common plane and forms a dihedral angle with respect thereto.

Claim 6

The biopsy needle as recited in claim 1 wherein said first and second longitudinal cutting edges are inclined coincidentally with respect to said axis.

Claim 7

The biopsy needle as recited in claim 5 wherein said first and second longitudinal cutting edges are oppositely inclined with respect to said axis.

Claim 8

The biopsy needle as recited in claim 6 wherein said first and second longitudinal cutting edges are symmetrically inclined with respect to said axis.

Claim 9

The biopsy needle as recited in claim 7 wherein said first acute angle is in the range of about 20°-50°.

Claim 10

The biopsy needle as recited in claim 1 including a stylet telescopically carried in said passage of said cannula and having a distal end located in said channel.

Claim 11

The biopsy needle as recited in claim 9 wherein said distal end of said stylet is conical.

Claim 12

The biopsy needle as recited in claim 9 wherein said distal end of said stylet is bevelled at the same angle as said first acute angle.

Claim 13

The biopsy needle as recited in claim 9 wherein said distal end of said stylet is bevelled at an angle greater than said first acute angle.

Claim 14

The biopsy needle as recited in claim 12 wherein said second acute angle is in the range of about 0° to 20°.

Claim 15

The biopsy needle as recited in claim 11 wherein said second acute angle is in the range of 0° to 10° and said first and second longitudinal cutting edges are symmetrically oppositely inclined.

Claim 16

The biopsy needle as recited in claim 14 wherein said first edges and second longitudinal cutting edges of both cannulas lie in a common plane.

Claim 17

The biopsy needle as recited in claim 14 wherein said first and second longitudinal cutting edges of both cannulas are coincidentally inclined with respect to said axis.

Claim 18

The biopsy needle as recited in claim 16 wherein said first and second longitudinal cutting edges of both cannulas are symmetrically inclined with respect to said axis.

Claim 19

A dual cannula biopsy needle adapted for both end cutting and side cutting of a tissue specimen from a tissue mass, said biopsy needle comprising: inner and outer hollow thin wall cylindrical cannulas each having a center passage and a longitudinal axis, said cannulas having generally identical open ended configurations but differing slightly in diameter so as to permit said inner cannula to be concentrically disposed within said outer cannula for relative axial and rotational movement therewithin, each of said cannulas having a distal end forming a circumferentially and axially opening channel, which channel is defined by a frontal tip section and an intermediate cutting section, said frontal tip section having a frontal cutting edge lying in a plane having a first acute angle with said longitudinal axis, said cutting section having first and second longitudinal cutting edges proximally contiguous with said frontal cutting edge of said frontal tip section, both of said longitudinal cutting edges of each said cannulas being parallelly inclined with respect to said longitudinal axis with said incline being at a second acute angle which is less than said first acute angle, said distal ends of said dual cannulas being alignable in a first position wherein the corresponding said sections lie in common planes, said frontal tip sections being effective upon forward movement of the cannulas into a tissue mass to axially incise a short length of said tissue, and said longitudinal cutting edges of said cannulas being effective for circumferentially severing the said incised tissue length from said tissue mass upon relative rotation of said cannulas, said cannulas being alternatively initially rotatable to a second position wherein said cutting sections establish an approximate continuation of the cylindrical proximal portions of said cannulas and the opposed said tip sections thereof define intersecting distal cutting sections which are effective upon axial movement of said cannulas into a tissue mass to sever a tissue specimen therefrom.

Claim 20

A dual cannula biopsy needle adapted for both end cutting and side cutting of a tissue specimen from a tissue mass, said biopsy needle comprising: inner and outer hollow thin wall cylindrical cannulas each having a center passage and a longitudinal axis, said cannulas having generally identical open ended configurations but differing slightly in diameter so as to permit said inner cannula to be concentrically disposed within said outer cannula for relative axial and rotational movement therewithin, each of said cannulas having a distal end forming a circumferentially and axially opening channel, which channel is defined by a frontal tip section and an intermediate cutting section, said frontal tip section having a frontal cutting edge lying in a plane having a first acute angle with said longitudinal axis, said cutting section having first and second longitudinal cutting edges proximally contiguous with said frontal cutting edge of said frontal tip section, both of said longitudinal cutting edges of each said cannulas being parallelly inclined with respect to said longitudinal axis with said incline being at a second acute angle which is less than said first acute angle, said distal ends of said dual cannulas being alignable in a first position wherein the corresponding said sections lie in common planes, said frontal tip sections being effective upon forward movement of the cannulas into a tissue mass to axially incise a short length of said tissue, and said longitudinal cutting edges of said cannulas being effective for circumferentially severing the said incised tissue length from said tissue mass upon relative rotation of said cannulas, said cannulas being alternatively initially rotatable to a second position wherein said cutting sections establish an approximate continuation of the cylindrical proximal portions of said cannulas and the opposed said tip sections thereof define intersecting distal cutting sections which are effective upon axial movement of said cannulas into a tissue mass to sever a tissue specimen therefrom.

Claim 21

The biopsy needle as recited in claim 18 wherein said common plane is coincident with said axis.

Claim 22

The biopsy needle as recited in claim 18 wherein said tip sections are symmetrically disposed with respect to said common plane and form dihedral angles with respect thereto.

Claim 23

The biopsy needle as recited in claim 20 wherein said first and second longitudinal cutting edges of both cannulas are oppositely inclined with respect to said axis.