Vitrectomy instrument with precision cutter stop
Provided herein are vitrectomy instruments and related systems and methods in which the vitrectomy instruments may include a forward needle stop and a cutter stop to reduce dimensional variation of a cutter of the vitrectomy instruments, allowing for a location of the port formed in a needle of the cutter to be positioned closer to a distal tip of the cutter. With the port located closer to a distal end of the cutter, the port is able to be positioned closer to the retina of an eye.
1. A vitrectomy instrument comprising:
a housing comprising:
a proximal end; and
a distal end;
a reciprocating cutter comprising:
a needle projecting from the distal end of the housing, the needle comprising:
a proximal end;
a distal end;
a first lumen; and
a port disposed at the distal end of the needle, the port providing fluid communication between an exterior of the needle and the first lumen;
an inner tube that extends within the first lumen of the needle, the inner tube comprising:
a second lumen; and
a cutting edge adapted to cut tissue drawn into the port; and
a needle stop coupled to the proximal end of the needle and comprising a first contact surface;
a cutter stop coupled to the inner tube and comprising a second contact surface, the first contact surface configured to contact the second contact surface limiting distal movement of the inner tube and defining a fully extended position of the inner tube; and
a motor operable to reciprocate the inner tube;
wherein the cutter stop further comprises a stop pad, and wherein the second contact surface is a surface of the stop pad.
2. The vitrectomy instrument of claim 1 , wherein the motor comprises a diaphragm disposed in the housing and movable in response to pneumatic pressure, the diaphragm connected to the inner tube of the reciprocating cutter such that the inner tube is movable with the diaphragm.
3. The vitrectomy instrument of claim 2 , wherein the diaphragm comprises a rigid diaphragm part connected to the inner tube and a flexible membrane connected to the rigid diaphragm part and to the housing.
4. The vitrectomy instrument of claim 1 wherein the cutter stop and the needle stop are formed from a metal.
5. The vitrectomy instrument of claim 1 , wherein the cutter stop and the inner tube are formed from a metal and wherein the cutter stop is welded to the inner tube.
6. The vitrectomy instrument of claim 5 , wherein the cutter stop comprises a stop ring that is welded to the inner tube.
7. The vitrectomy instrument of claim 1 , wherein the cutter stop comprises a stop ring.
8. A vitrectomy instrument comprising:
a housing comprising:
a proximal end; and
a distal end;
a reciprocating cutter comprising:
a needle projecting from the distal end of the housing, the needle comprising:
a proximal end;
a distal end;
a first lumen; and
a port disposed at the distal end of the needle, the port providing fluid communication between an exterior of the needle and the first lumen:
an inner tube that extends within the first lumen of the needle, the inner tube comprising:
a second lumen; and
a cutting edge adapted to cut tissue drawn into the port; and
a needle stop coupled to the proximal end of the needle and comprising a first contact surface;
a cutter stop coupled to the inner tube and comprising a second contact surface, the first contact surface configured to contact the second contact surface limiting distal movement of the inner tube and defining a fully extended position of the inner tube; and
a motor operable to reciprocate the inner tube;
wherein the needle stop further comprises:
a needle stop proximal component;
a needle stop distal component coupled to the needle stop proximal component;
wherein the needle stop proximal component is received into a cavity defined by the needle stop distal component.
9. The vitrectomy instrument of claim 8 , wherein the motor comprises a diaphragm disposed in the housing and movable in response to pneumatic pressure, the diaphragm connected to the inner tube of the reciprocating cutter such that the inner tube is movable with the diaphragm.
10. The vitrectomy instrument of claim 9 , wherein the diaphragm comprises a rigid diaphragm part connected to the inner tube and a flexible membrane connected to the rigid diaphragm part and to the housing.
11. The vitrectomy instrument of claim 8 wherein the cutter stop and the needle stop are formed from a metal.
12. The vitrectomy instrument of claim 8 , wherein the cutter stop and the inner tube are formed from a metal and wherein the cutter stop is welded to the inner tube.
13. The vitrectomy instrument of claim 12 , wherein the cutter stop comprises a stop ring that is welded to the inner tube.
14. The vitrectomy instrument of claim 8 , wherein the cutter stop comprises a stop ring.
15. A vitrectomy instrument comprising:
a housing comprising:
a proximal end; and
a distal end;
a reciprocating cutter comprising:
a needle projecting from the distal end of the housing, the needle comprising:
a proximal end;
a distal end;
a first lumen; and
a port disposed at the distal end of the needle, the port providing fluid communication between an exterior of the needle and the first lumen;
an inner tube that extends within the first lumen of the needle, the inner tube comprising:
a second lumen; and
a cutting edge adapted to cut tissue drawn into the port; and
a needle stop coupled to the proximal end of the needle and comprising a first contact surface;
a cutter stop coupled to the inner tube and comprising a second contact surface, the first contact surface configured to contact the second contact surface limiting distal movement of the inner tube and defining a fully extended position of the inner tube; and
a motor operable to reciprocate the inner tube;
wherein the needle stop further comprises:
a needle stop proximal component;
a needle stop distal component coupled to the needle stop proximal component;
wherein the needle stop proximal component comprises:
a proximal portion having a first cross-sectional size;
a distal portion having a second cross-sectional size smaller than the first cross-sectional size; and
a shoulder joining the proximal portion and the distal portion.
16. The vitrectomy instrument of claim 15 , wherein the proximal portion of the needle stop proximal component is received into a cavity defined by the needle stop distal component.
17. The vitrectomy instrument of claim 16 , wherein the needle stop proximal component is welded to the needle stop distal component.
18. The vitrectomy instrument of claim 15 , wherein the shoulder defines the first contact surface.
19. The vitrectomy instrument of claim 15 , wherein the motor comprises a diaphragm disposed in the housing and movable in response to pneumatic pressure, the diaphragm connected to the inner tube of the reciprocating cutter such that the inner tube is movable with the diaphragm.
20. The vitrectomy instrument of claim 19 , wherein the diaphragm comprises a rigid diaphragm part connected to the inner tube and a flexible membrane connected to the rigid diaphragm part and to the housing.
21. The vitrectomy instrument of claim 15 wherein the cutter stop and the needle stop are formed from a metal.
22. The vitrectomy instrument of claim 15 , wherein the cutter stop and the inner tube are formed from a metal and wherein the cutter stop is welded to the inner tube.
23. The vitrectomy instrument of claim 22 , wherein the cutter stop comprises a stop ring that is welded to the inner tube.
24. The vitrectomy instrument of claim 15 , wherein the cutter stop comprises a stop ring.