WO2002030303A1

WO2002030303A1 - Microsurgical instrument

Info

Publication number: WO2002030303A1
Application number: PCT/US2001/028030
Authority: WO
Inventors: Dyson W. Hickingbotham
Original assignee: Alcon, Inc.
Priority date: 2000-10-12
Filing date: 2001-09-06
Publication date: 2002-04-18
Also published as: AU2001287131A1

Abstract

An improved handle for a microsurgical instrument, as well as microsurgical instruments using the handle, are disclosed. The handle includes a first portion for supporting a human thumb, and an arm rotationally coupled to the first portion. The arm also has a second surface for supporting a human index finger. The handle further includes a knob rotationally coupled to the first portion. The knob is for coupling to a microsurgical tool, such as a microsurgical scissors or forceps. The handle allows a human, using one hand, to actuate the microsurgical tool by moving the arm toward the first portion, and to rotate the microsurgical tool about a longitudinal axis of the tool by using a middle or ring finger to rotate the knob.

Description

MICROSURGICAL INSTRUMENT

Field of the Invention

The present invention generally pertains to microsurgical instruments. More particularly, but not by way of limitation, the present invention pertains to ophthalmic microsurgical instruments, especially such instruments designed for use in the posterior segment of the eye. Description of the Related Art

During ophthalmic microsurgery, it is often necessary to dissect, cut, delaminate or otherwise manipulate delicate tissues within the eye. Microsurgical tools, such as microscissors, microforceps and other devices generally are used for such manipulations. Many of these tools require some sort of actuation. For example, the blades of "horizontal" microscissors must be rotated across each other in order to cut, the blades of

"vertical" microscissors must be brought together in order to cut, and the grasping tips of a "vertical" microforceps must be bought together in order to grasp. Typically in such tools, one blade or grasping tip is stationary, and the other blade or tip is movable. Examples of such conventional microsurgical scissors and forceps are the Grieshaber® Sutherland Rotable microscissors and microforceps available from Alcon Laboratories,

Inc. of Fort Worth, Texas.

U.S. Patent No. 4,258,716 to Sutherland, which is incorporated herein by this reference, provides an example of such prior art microsurgical tools as well as a handle for such tools. FIGS. 1-2 illustrate a microsurgical instrument 8 as shown and described in the Sutherland '716 patent. Instrument 8 generally includes a handle 10 with a vertical microforceps 13 removably coupled thereto. Although not shown in FIGS. 1-2, member 11 of handle 10 is long enough for a surgeon to comfortably grasp instrument 8. FIG. 1

illustrates forceps 13 in a closed position. FIG. 2 illustrates forceps 13 in an open

position. As shown in FIG. 2, when a surgeon uses his index or middle finger to push arm 16 in a downward direction, second arm 17 "wipes across" the proximal surface of

plunger 19, causing plunger 19 to move within hollow bore 13 toward the distal end of forceps 13. Plunger 19 causes longitudinally movable member 60, and thus rod 57, to

move toward a distal end of forceps 13. Such movement causes jaw 58 of forceps 13 to

move away from stationery jaw 56 of forceps 13. When the surgeon removes the downward force on arm 16, spring 63 returns forceps 13 to the closed position, and arm

16 is returned to its original position as shown in FIG. 1. As is described in greater detail in the Sutherland '716 patent, this mechanism can also be used to actuate "vertical"

microscissors, and a similar mechanism can be used to rotate "horizontal" microscissors.

While enjoying substantial commercial success in the surgical market, microsurgical instrument 8 is subject to certain limitations. For example, after repeated actuation of arm 16, the proximal surface of plunger 19 may be worn by the wiping action

of arm 17. In this case, the actuation of the forceps 13 may not feel "smooth" to the surgeon. Instrument 8 has a rotable ring 28, which is used to position the blades of jaws 56 and 58 of forceps 13 at a particular angle relative to its longitudinal axis. However,

instrument 8 typically requires the surgeon to use his or her second hand to rotate ring 28. In addition, some surgeons are uncomfortable with the distance between arm 16 and the

distal tip of forceps 13.

U.S. Patent No. 4,433,687 to Burke et al. provides another example of

conventional microsurgical scissors employing a handle that is squeezed together to operate the scissors. An actuating mechanism in the handle translates linear finger motion into rotary motion necessary for the cutting action. However, the scissors of the '687

Burke patent require a fairly complex, relatively expensive drive mechanism.

Therefore, a need continues to exist in the microsurgical instrument field for a

simple, inexpensive actuating handle for microsurgical tools that does not suffer from the above-referenced limitations. Preferably, such a handle will allow a surgeon to dispose a

microsurgical tool in a very small aperture, and to manipulate the tool at various angles relative to the aperture, without the necessity of having to enlarge the aperture to any substantial extent.

Summary of the Invention

The present invention is directed to a handle for a microsurgical instrument. The

handle includes a first portion for supporting a human thumb, and an arm rotationally coupled to the first portion. The arm also has a second surface for supporting a human index finger. The handle further includes a knob rotationally coupled to the first portion.

The knob is for coupling to a microsurgical tool, such as a microsurgical scissors or forceps. The handle allows a human, using one hand, to actuate the microsurgical tool by moving the arm toward the first portion, and to rotate the microsurgical tool about a longitudinal axis of the tool by using a middle finger to rotate the knob.

Brief Description of the Drawings

For a more complete understanding of the present invention, and for further objects and advantages thereof, reference is made to the following description taken in

conjunction with the accompanying drawings in which:

FIG. 1 is a side, partially sectional view of a conventional microsurgical forceps in a closed position;

FIG. 2 is a side, partially sectional view of the forceps of FIG. 1 in an open

position; FIG. 3 is a perspective view of a microsurgical instrument according to a preferred embodiment of the present invention;

FIG. 4 is an exploded, perspective view of the microsurgical instrument of FIG. 3;

FIG. 5 is an enlarged, fragmentary view of the housing, lever arm, and sleeve of

the microsurgical instrument of FIG. 3; and

FIG. 6 is a perspective view of a surgeon holding the microsurgical instrument of FIG. 3 in the preferred operating position. Detailed Description of the Preferred Embodiment

The preferred embodiment of the present invention and their advantages are best

understood by referring to FIGS. 3 through 6 of the drawings, like numerals being used

for like and corresponding parts of the various drawings.

FIG. 3 shows a microsurgical instrument 100 according to a preferred embodiment

of the present invention. Instrument 100 is preferably for ophthalmic microsurgical

applications, but may also be used in otorhinolaryngological, neurosurgical, and other fine microsurgical uses, particularly where the surgery is being performed in a body cavity.

Instrument 100 is also useful in entomology and botany. A particularly useful application of instrument 100 is in microsurgical applications in the posterior segment of the eye.

Instrument 100 generally includes a handle 102 and a microsurgical tool 104.

Microsurgical tool 104 is preferably scissors that cut in a plane disposed at an angle to the longitudinal axis of tool 104 ("horizontal microscissors"), scissors that cut along the longitudinal axis of tool 104 ("vertical microscissors"), or forceps which operate along the longitudinal axis of tool 104 ("vertical microforceps"). The construction and operation of

such microsurgical tools is described in more detail in the Sutherland '716 patent. As shown in FIG. 3, microsurgical tool 104 is a vertical forceps substantially identical to

forceps 13 of FIGS. 1 and 2. Handle 102 generally includes a grasping portion 106 and an arm 108. Grasping portion 106 preferably has two transverse holes 110, a thumb rest 112, a lower surface

113, a rounded end 114, and an upper surface 115. Arm 108 is preferably rotationally coupled to and cantilevered from upper surface 115 of grasping portion 106. Arm 108 also preferably has a finger rest area 116. As shown best in FIG. 6, a surgeon may

comfortably grasp handle 102 with his or her thumb 103 positioned in thumb rest 112 and along lower surface 113 of grasping portion 106, and his or her index finger 105 in finger

rest area 116 and along arm 108 and upper surface 115 of grasping portion 106. In this position, rounded area 114 fits securely in "crook" 107 of the surgeon's hand between his

or her thumb 103 and index finger 105.

Referring now to FIGS. 3 and 4, handle 102 also includes a housing 118, a lever

arm 120, a plunger 122, a sleeve 124, an o-ring 126, a coupler 128, and a rotating knob 130. Housing 118 has a cylindrical geometry with a hollow bore therethrough. Housing 118 also has a slanted surface 132 on its distal end. The proximal end of housing 118 is received within a mating cylindrical bore (not shown) within mount 133 of grasping

portion 106 of handle 102. Lever arm 120 preferably has a tubular geometry and includes a roller 134 rotationally mounted on a first end, and an angled portion 136 on a lower end.

Angled portion 136 is designed to mate with slanted surface 132 of housing 118. Plunger 122 has a cylindrical geometry. The proximal end of plunger 122 passes between the adjacent tubular members of angled portion 136 of lever arm 120. The distal end of

plunger 122 is received within the hollow bore of sleeve 124. When instrument 100 is

fully assembled, the distal end of plunger 122 is for operably engaging a proximal end of an actuating pin of microsurgical tool 104, which is also disposed within the hollow bore

of sleeve 124. Sleeve 124 preferably has a cylindrical geometry with a hollow bore therethrough. Sleeve 124 also has a slot 138 near its proximal end, and male threads 140 on its distal end. Threads 140 mate with female threads (not shown) on the proximal end of coupler 128. O-ring 126 forms a tight seal between sleeve 124 and coupler 128. Coupler 128 is threadedly and rotationally coupled to rotating knob 130. Rotating knob 130 preferably has a generally conical geometry with a knurled surface for engaging a surgeon's finger. Rotating knob 130 may be locked against rotation via a set screw (not shown). Microsurgical tool 104 is threadedly coupled with knob 130. As is best shown in FIG. 6, a surgeon may use his or her middle or ring finger to rotate knob 130, and thus microsurgical tool 104, with the same hand being used to hold and actuate instrument 100. A pin 142 is disposed through slot 138 of sleeve 124 and bore 144 of plunger 122 to limit the travel of plunger 122 within sleeve 124 and to prevent plunger 122 from falling out of sleeve 124. The range of travel of plunger 122 within sleeve 124 is preferably about 2 mm to about 3 mm.

FIG. 5 shows an enlarged view of housing 118, lever arm 120, and sleeve 124 in an assembled state. Housing 118 preferably has a ledge 146 extending from slanted surface 132. A groove 148 is preferably formed in ledge 146 proximate slanted surface

132. A lower end 150 of angled portion 136 of lever arm 120 rests within groove 148.

Grasping portion 106 and arm 108 of handle 102 are preferably made from a polymer that provides' sufficient flexibility to rotationally couple arm 108 to upper surface 115, and that may be easily sterilized via an autoclave. Rotating knob 130 and roller 134 are preferably made from a polymer that may be easily sterilized via an autoclave. A preferred polymer for all of these components of handle 102 is polysulfone. O-ring 126 is preferably made from an elastomer. The remaining portions of handle 102, as well as microsurgical tool 104, are preferably made from a metal that may be easily sterilized via an autoclave. A preferred metal is surgical stainless steel. Having described the structure of a preferred embodiment of microsurgical instrument 100, the preferred method of using instrument 100 will now be described in greater detail in connection with microsurgical forceps 104. The surgeon first grasps

instrument 100 via handle 102 as shown in FIG. 6. As described hereinabove, handle 102

fits comfortably within crook 107 of the surgeon's hand. In addition, the surgeon's hand is located very close to the distal end of forceps 104, which facilitates the manipulation of forceps 104. To actuate the grasping tips of microsurgical forceps 104, the surgeon

simply exerts a downward force on arm 108 with his or her index finger 105. Arm 108, in cooperation with roller 134, causes angled portion 136 of lever arm 120 to rotate about its

end 150 toward the distal end of forceps 104. During this rotation, angled portion 136 causes causes pin 142 to move forward within slot 138 of sleeve 124. This movement in

turn causes plunger 122 to move linearly toward the distal end of forceps 104 within sleeve 124. The distal end of plunger 122 then contacts the proximal end of the actuating

pin of forceps 104, causing it to move within sleeve 124, coupler 128, rotating knob 130, and hollow barrel 104a of forceps 104. This movement of the actuating pin moves the grasping tips from a closed position, to an open position. When the surgeon quits

exerting the downward force on arm 108, a spring, which is preferably disposed in barrel 104a of forceps 104, moves the actuating pin of forceps 104 in a proximal direction to close the grasping tips of forceps 104, and to return arm 108 to its original position, as

shown in FIG. 3.

Using the same hand that is used to acutate forceps 104, the surgeon can easily

rotate the grasping tips of forceps 104 using his or her middle or ring finger to turn knob

130. In addition, the actuating mechanism provided by arm 108, housing 118, lever arm 120, roller 134, pin 142, slot 138, and plunger 122 do not suffer from the performance

problems exhibited by conventional microsurgical instrument 8 caused by wear on the proximal portion of plunger 19 by arm 17. Of course, microsurgical instrument 100 may be operated in the above-described manner to actuate vertical or horizontal microscissors, or another similar microsurgical instrument.

From the above, it may be appreciated that the present invention provides a

simple, inexpensive actuating handle for microsurgical tools that provides improved performance over conventional handles. The handle allows a surgeon to dispose a

microsurgical tool in a very small aperture, and to manipulate the tool at various angles relative to the aperture, without the necessity of having to enlarge the aperture to any

substantial extent. It is believed that the operation and construction of the present invention will be apparent from the foregoing description. While the apparatus and methods shown or

described above have been characterized as being preferred, various changes and modifications may be made therein without departing from the spirit and scope of the

invention as defined in the following claims.

Claims

What is claimed is:

1. A handle for a microsurgical instrument, comprising: a first portion for supporting a human thumb; an arm rotationally coupled to said first portion, and having a second surface for supporting a human index finger; and

a knob rotationally coupled to said first portion and for coupling to a microsurgical tool; whereby a human user can, using one hand, actuate said microsurgical tool by moving said arm toward said first portion, and rotate said microsurgical tool about a longitudinal axis of said tool by using a middle finger or ring finger to rotate said knob.

2. The handle of claim 1, wherein said microsurgical tool comprises a forceps having first and second grasping tips on a distal end, and wherein said actuation of said microsurgical tool moves said first grasping tip relative to said second grasping tip.

3. The handle of claim 1 , wherein said microsurgical tool comprises a scissors having first and second cutting blades on a distal end, and wherein said actuation of said microsurgical tool moves said first blade relative to said second blade.

4. The handle of claim 3, wherein said scissors are vertical scissors.

5. The handle of claim 3, wherein said scissors are horizontal scissors.

6. A microsurgical instrument, comprising: a microsurgical tool; and a handle, said handle comprising: a first portion for supporting a human thumb; an arm rotationally coupled to said first portion, and having a second surface for supporting a human index finger; and a knob rotationally coupled to said first portion and coupled to said microsurgical tool;

whereby a human user can, using one hand, actuate said microsurgical tool by

moving said arm toward said first portion, and rotate said microsurgical tool about a

longitudinal axis of said tool by using a middle finger or ring finger to rotate said knob.

7. The microsurgical instrument of claim 6, wherein said microsurgical tool comprises a forceps having first and second grasping tips on a distal end, and wherein

said actuation of said microsurgical tool moves said first grasping tip relative to said

second grasping tip.

8. The microsurgical instrument of claim 6, wherein said microsurgical tool

comprises a scissors having first and second cutting blades on a distal end, and wherein said actuation of said microsurgical tool moves said first blade relative to said second

blade.

9. The microsurgical instrument of claim 8, wherein said scissors are vertical

scissors.

10. The microsurgical instrument of claim 8, wherein said scissors are

horizontal scissors.