Surgical tool and method for extracting tissue from wall of an organ

• US 20030208217A1
• Filed: 05/01/2002
• Published: 11/06/2003
• Est. Priority Date: 05/01/2002
• Status: Active Grant

• Current Assignee: Dot DAN Opthalmic Technologies Limited
• Original Assignee: Dot DAN Opthalmic Technologies Limited
• Inventors: Dan, Jacob
• Granted Patent: US 7,041,114 B2
• Time in Patent Office: Days
• US Class Current: 606/166
• CPC Class Codes: A61F 9/00781 Apparatus for modifying intraocular pressure, e.g. for glaucoma treatment drainage implants in general A61M27/002
• CPC Class Codes: A61F 9/0133 Knives or scalpels specially adapted therefor

Abstract

The present invention is concerned with methods and equipment for the treatment of the eye and more particularly with an instrument to increase eye filtration and treat glaucoma. The instrument is surgical tool operated entirely by the surgeon'"'"'s hands and is composed of a hand-piece and an eye-penetrating intraocular segment each having two opponent and reciprocally operating fork-like arms and blade-sharp leaves, respectively. The eye-penetrating segment is a rigid embodiment of a size to create a limbus-pointing tunnel in the cornea, penetrate the eye of a patient through a water tight incision and, in a five step dissect and extract procedure, remove from within the eye a trabecular tissue block leaving the incision to self-seal by intraocular pressure. In the same “modus operandi”, a sample tissue can be extracted from any other hollowed or parenchimatous organ.

Claims

1. A method for extracting a tissue block from the angle of an eye, the method comprising:

(a) forming a first elongated slit of substantially constant width entering at a peripheral region of the cornea, said first elongated slit providing a face of a self-sealing flap having a terminal angle of no more than 25°

;

(b) employing a tool inserted via said first elongated slit to the limbus underlying the conjunctiva to form a plurality of additional slits so as to define the tissue block; and

(c) withdrawing the tissue block along said first elongated slit such that said first elongated slit is temporarily elastically deformed to allow passage of the tissue block and is then sealed by said self-sealing flap.

2. The method of claim 1, further comprising forming a second undercut slit from a first position along said first elongated slit so as to further define said self-sealing flap.

3. The method of claim 1, wherein said plurality of additional slits includes a second undercut slit from a first position along said first elongated slit so as to further define said self-sealing flap and so as to form at least a proximal cut of the tissue block.

4. The method of claim 3, wherein said plurality of additional slits further includes a pair of side cuts below said first elongated slit so as to define sides of the tissue block.

5. The method of claim 4, wherein said plurality of additional slits further includes a lower slit extending into the angle of the eye so as to at least partially define a lower side of the tissue block.

6. The method of claim 5, wherein said plurality of additional slits further includes a third slit from a second position along said first elongated slit distal to said first position so as to form at least a distal cut of the tissue block.

7. The method of claim 6, wherein said first elongated slit, said second undercut slit, said third slit and said side cuts are all performed by a manually operated mechanical tool inserted along said first elongated slit.

8. The method of claim 1, wherein said first elongated slit extends at a maximum depth sufficiently small to render an instrument inserted therein visible through overlying tissue.

9. The method of claim 1, wherein said substantially constant width of said first elongated slit is less than 5 mm.

10. A method for extracting a tissue block from the wall of a hollow organ and forming a self-sealing flap in tissue of the wall, the method comprising:

(a) forming a first elongated slit of substantially constant width extending from an outer surface of the wall into the wall, said first elongated slit forming a face of a self-sealing flap;

(b) forming a plurality of additional slits so as to define the tissue block, said plurality of additional slits including;

(i) a second undercut slit from a first position along said first elongated slit so as to further define said self-sealing flap so as to form a terminal angle of no more than 25°

, said second undercut slit additionally forming at least a proximal cut of the tissue block,

(ii) a pair of side cuts below said first elongated slit so as to define sides of the tissue block, and

(iii) a third slit from a second position along said first elongated slit distal to said first position so as to form at least a distal cut of the tissue block; and

(c) withdrawing the tissue block along said first elongated slit such that said first elongated slit is temporarily elastically deformed to allow passage of the tissue block and is then sealed by said self-sealing flap.

11. The method of claim 10, wherein said first elongated slit, said second undercut slit, said third slit and said side cuts are all performed by a manually operated mechanical tool inserted along said first elongated slit.

12. The method of claim 10, wherein said plurality of additional slits further includes a lower slit so as to at least partially define a lower face of the tissue block.

13. A surgical tool for forming a self-sealing flap in tissue of a wall of a hollow organ during a procedure for extracting a tissue block from the wall, the surgical tool comprising a tool head including:

(a) an elongated support element having a direction of elongation and configured for insertion along a first slit parallel to said direction of elongation into the tissue of the wall; and

(b) a blade element pivotally mounted on said support element so as to be pivotable about an axis perpendicular to said direction of elongation, said blade element including a rear blade with at least one deflecting feature configured for forming a second slit diverging from said first slit during withdrawal of the tool along the first slit, thereby forming a self-sealing flap in the tissue of the wall.

14. The surgical tool of claim 13, wherein a plane passing through said support element parallel to both said direction of elongation and said axis is referred to as a tool plane, and wherein said blade element is mounted on said support element via a lever mechanism, said lever mechanism being configured to allow displacement of said blade element from an in-plane position in which said axis lies substantially within said tool plane to an out-of-plane position in which said axis is displaced so as to be parallel to, but removed from, said tool plane.

15. The surgical tool of claim 14, wherein said lever mechanism includes a pair of lever arms each having a first end pivotally engaged with said support element and a second end pivotally engaged with said blade element.

16. The surgical tool of claim 15, wherein said lever arms are configured such that, when said blade element assumes said out-of-plane position, at least part of each of said lever arms presents a blade edge extending substantially perpendicular to said tool plane and oriented for cutting parallel to said direction of elongation.

17. The surgical tool of claim 14, wherein said lever mechanism further includes a lock element configured to retain said blade element in said out-of-plane position.

18. The surgical tool of claim 17, wherein said blade element has a substantially planar upper surface, the lever mechanism further including a resilient biasing element deployed such that, when said blade element assumes said out-of-plane position, said biasing element biases said blade element to a position with said upper surface substantially parallel to said tool plane.

19. The surgical tool of claim 18, wherein said blade element further includes a front blade configured for cutting a slit parallel to said tool plane during advancing of the tool along the first slit.

20. The surgical tool of claim 19, wherein said blade element is referred to as said first blade element, and wherein said axis is referred to as said first axis, the tool head further including a second blade element pivotally mounted on said support element distally with respect to said first blade element, said second blade element being pivotable about a second axis parallel to said first axis, said second blade element including a rear blade with at least one deflecting feature configured for forming an additional slit diverging from said first slit during withdrawal of the tool along the first slit.

21. The surgical tool of claim 20, wherein said lever mechanism further includes a retention element deployed such that, when said blade element assumes said in-plane position, said retention element abuts a surface of said second blade element so as to limit pivotal movement of said second blade element about said second axis and, when said blade element assumes said out-of-plane position, said retention element is removed from said second blade element so as not to limit pivotal movement of said second blade element about said second axis.

22. The surgical tool of claim 13, wherein said elongated support element includes a fork portion formed with two projecting arms, said blade element being mounted between said projecting arms.

23. The surgical tool of claim 22, wherein a distal portion of each of said projecting arms is formed as a blade parallel to said direction of elongation.

24. The surgical tool of claim 13, wherein said blade element further includes a pair of side blades extending along a majority of a length between said front blade and said rear blade in a direction substantially perpendicular to said axis.

25. The surgical tool of claim 24, wherein said blade element further includes an opening substantially circumscribed by said front blade, said rear blade and said pair of side blades.

26. The surgical tool of claim 13, further comprising a blade control assembly including at least one abutment element mechanically interconnected with said elongated support element so as to be movable relative to said elongated support element between a closed position in which said at least one abutment element abuts said blade element so as to restrain pivotal movement of said blade element and an open position in which said abutment element is removed from said blade element so as to allow pivotal movement of said blade element.

27. The surgical tool of claim 26, wherein said at least one abutment element is implemented as a second blade assembly including:

(a) a second elongated support element having a second direction of elongation; and

(b) a second blade element pivotally mounted on said second support element so as to be pivotable about a second axis perpendicular to said second direction of elongation.

28. The surgical tool of claim 27, wherein said second blade element includes a second front blade configured for cutting a primary slit parallel to said second axis during advancing of the tool into the tissue of the wall, and a second rear blade with at least one deflecting feature configured for forming a secondary slit diverging from said primary slit during withdrawal of the tool along the first slit.

29. The surgical tool of claim 27, wherein said second blade element is restrained from pivotal movement when said second blade assembly assumes said closed position.

30. The surgical tool of claim 27, wherein said second blade assembly is resiliently biased towards said open position.

31. A surgical tool for forming a self-sealing flap in tissue of a wall of a hollow organ and extracting a tissue block from the wall, the surgical tool comprising:

(a) a first blade assembly including;

(i) a first elongated support element having a first direction of elongation, and

(ii) a first blade element pivotally mounted on said first support element so as to be pivotable about a first axis perpendicular to said first direction of elongation, said first blade element including a first front blade configured for cutting a first forward slit parallel to said first axis during advancing of the tool, and a first rear blade with at least one deflecting feature configured for forming a first reverse slit diverging from said first forward slit during withdrawal of the tool along the first forward slit;

(b) a second blade assembly including;

(i) a second elongated support element having a second direction of elongation, and

(ii) a second blade element pivotally mounted on said second support element so as to be pivotable about a second axis perpendicular to said second direction of elongation, said second blade element including a second front blade configured for cutting a second forward slit parallel to said second axis during advancing of the tool, and a second rear blade with at least one deflecting feature configured for forming a second reverse slit diverging from said second forward slit during withdrawal of the tool along the second forward slit; and

(c) a mechanical linkage interconnecting between said first elongated support element and said second elongated support element so as to define a range of relative movement between a closed position in which said first blade assembly is closed against said second blade assembly and an open position in which said first blade assembly and said second blade assembly are spaced apart.

32. The surgical tool of claim 31, wherein said first blade assembly and said second blade assembly are configured such that, when in said closed position, said first blade element and said second blade element are restrained against pivotal movement.

33. The surgical tool of claim 31, wherein each of said first elongated support element and said second elongated support element includes a fork portion formed with two projecting arms, said first and second blade elements being mounted between said projecting arms.

34. The surgical tool of claim 33, wherein a distal portion of each of said projecting arms is formed as a blade parallel to said direction of elongation.

35. The surgical tool of claim 31, wherein said blade element further includes a pair of side blades extending along a majority of a length between said front blade and said rear blade in a direction substantially perpendicular to said axis.

36. The surgical tool of claim 35, wherein said blade element further includes an opening substantially circumscribed by said front blade, said rear blade and said pair of side blades.