WO2002030302A1

WO2002030302A1 - Microsurgical instrument

Info

Publication number: WO2002030302A1
Application number: PCT/US2001/028012
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: AU2001292584A1

Abstract

An improved handle for a microsurgical instrument, as well as microsurgical instruments using the handle, are disclosed. The handle includes a grasping member for grasping the instrument between an index finger and a middle finger of a human hand. The handle also includes an actuating member rotationally coupled to the instrument and for operatively engaging a microsurgical tool. The actuating member has a geometry for mating with a human thumb. The handle allows a human to actuate the microsurgical tool by moving the actuating member with the thumb.

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 grasping member for grasping the instrument between an index finger and a middle finger of a human hand. The handle also includes an acutating member rotationally coupled to the instrument and for operatively engaging a microsurgical tool. The actuating member has a geometry for mating with a human thumb. The handle allows a human to actuate the microsurgical tool by moving the actuating member with the thumb. 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.

FIGS. 3 and 4 show 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, a microsurgical tool 104, and a

cap 105. 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. 4, microsurgical tool 104 is a vertical forceps substantially identical to forceps 13 of FIGS. 1 and 2.

Handle 102 generally includes a grasping member 106, an acutating mechanism

108, and a rotating knob 110. Grasping member 106 preferably has a length and a circular, hexagonal, or other polygonal cross-sectional geometry that facilitates a surgeon's grasping and manipulation of instrument 100. Actuating mechanism 108

preferably includes a housing 112, a actuating member 114, a lever arm 116, a plunger

118, a sleeve 120, an o-ring 122, and a coupler 124.

Housing 112 has a cylindrical geometry with a hollow bore therethrough. Housing

112 also has a slanted surface 126 on its distal end. The proximal end of housing 112 is received within a mating cylindrical bore 128 on the distal end of grasping member 106.

Actuating member 114 preferably has a ring-shaped geometry designed to mate with a surgeon's thumb. Alternatively, actuating member 114 may have a disk-shaped geometry, a rectangular geometry, a saucer-shaped geometry, or other geometry for mating with a surgeon's thumb. Lever arm 116 preferably has a tubular geometry and includes an angled portion 130 on a lower end. Angled portion 130 is designed to mate with slanted surface 126 of housing 112. Plunger 118 has a cylindrical geometry. The proximal end

of plunger 118 passes between the adjacent tubular members of angled portion 130 of

lever arm 116. The distal end of plunger 118 is received within the hollow bore of sleeve

120. When instrument 100 is fully assembled, the distal end of plunger 118 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 120. Sleeve 120 preferably has a

cylindrical geometry with a hollow bore therethrough. Sleeve 120 also has a slot 132 near

its proximal end, and male threads 134 on its distal end. Threads 134 mate with female

threads (not shown) on the proximal end of coupler 124. O-ring 122 forms a tight seal between sleeve 120 and coupler 124. Coupler 124 is threadedly and rotationally coupled

to rotating knob 110. Rotating knob 110 preferably has a generally conical geometry with

a knurled surface for engaging a surgeon's finger. Rotating knob 110 may be locked against rotation via a set screw (not shown). Microsurgical tool 104 is threadedly coupled

with knob 110. A pin 136 is disposed through slot 132 of sleeve 120 and bore 138 of plunger 118 to limit the travel of plunger 118 within sleeve 120 and to prevent plunger

118 from falling out of sleeve 120. The range of travel of plunger 118 within sleeve 120 is preferably about 2 mm to about 3 mm, Cap 105 is removably coupled to rotating knob

110 and covers microsurgical tool 104. Cap 105 preferably frictionally couples with the

outer surface of knob 110.

As shown best in FIG. 6, a surgeon may comfortably grasp grasping member 106 and rotating knob 110 between his or her index finger 140 and middle finger 142 using a grip similar to which one would hold a pencil. A surgeon may then use his or her thumb 143 to push downward on acutating member 114 to actuate microsurgical tool 104. In

addition, a surgeon may use his or her index finger 140 or middle finger 142 to rotate

knob 110, and thus microsurgical tool 104, with the same hand being used to hold and actuate instrument 100.

FIG. 5 shows an enlarged view of housing 112, actuating member 114, lever arm

116, and sleeve 120 in an assembled state. Housing 112 preferably has a ledge 150

extending from slanted surface 126. A groove 152 is preferably formed in ledge 150

proximate slanted surface 126. A lower end 154 of angled portion 130 of lever arm 116

rests within groove 152.

Cap 105, rotating knob 110, and actuating member 114 are preferably made from

a conventional plastic that may be easily sterilized via an autoclave. A preferred plastic is

polysulfone. O-ring 122 is preferably made from an elastomer. The remaining portions of handle 102, as well as microsurgical tool 104, are preferably made from a conventional

metal that may be easily sterilized via an autoclave. A preferred metal for grasping member 106 is aluminum. A preferred metal for the remaining portions of handle 102 is surgical stainless steel. A preferred metal for microsurgical tool 104 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, the surgeon may comfortably hold handle 102 using a grip similar to that used to hold a

pencil. 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 acutating member 114 with his or her thumb 143. Angled portion 130 of lever arm 116 rotates about its end 154 toward the distal end of forceps 104. During this rotation, angled

portion 130 causes pin 136 to move forward within slot 132 of sleeve 120. This movement in turn causes plunger 118 to move linearly toward the distal end of forceps

104 within sleeve 120. The distal end of plunger 118 then contacts the proximal end of the actuating pin of forceps 104, causing it to move within sleeve 120, coupler 124,

rotating knob 110, 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 actuating member 114, 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

actuating member 114 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 index finger 140 or middle finger 142 to turn knob 110. In addition, actuating mechanism 108 does 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 grasping member for grasping the instrument between an index finger and a middle finger of a human hand; and

an acutating member rotationally coupled to said instrument and for operatively

engaging a microsurgical tool, said actuating member having a geometry for mating with a human thumb;

whereby a human user can actuate said microsurgical tool by moving said actuating member with said thumb.

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. The handle of claim 1 further comprising a knob rotationally coupled to

said instrument and for coupling to said microsurgical tool, whereby a human user can

rotate said microsurgical tool about a longitudinal axis of said tool by rotating said knob with an index finger or a middle finger of a same hand used to actuate said tool.

7. The handle of claim 1 wherein said acutating member has a ring-shaped

geometry.

8. A microsurgical instrument, comprising:

• a microsurgical tool; and a handle, said handle comprising:

a grasping member for grasping the instrument between an index finger and a middle finger of a human hand; and an acutating member rotationally coupled to said instrument and for operatively engaging said microsurgical tool, said actuating member having a geometry

for mating with a human thumb; *

9. The microsurgical instrument of claim 8, 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.

10. The microsurgical instrument of claim 8, 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.

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

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

horizontal scissors.

13. The microsurgical instrument of claim 8 further comprising a knob

rotationally coupled to said instrument and coupled to said microsurgical tool, whereby a

human user can rotate said microsurgical tool about a longitudinal axis of said tool by

rotating said knob with an index finger or a middle finger of a same hand used to actuate

said tool.

14. The microsurgical instrument of claim 8 wherein said acutating member has a ring-shaped geometry.