WO1999055240A1

WO1999055240A1 - Irrigation sleeve and ultrasonic needle for phacoemulsification apparatus

Info

Publication number: WO1999055240A1
Application number: PCT/US1999/009060
Authority: WO
Inventors: David M. Van Voorhis
Original assignee: Staar Surgical Company, Inc.
Priority date: 1998-04-28
Filing date: 1999-04-27
Publication date: 1999-11-04
Also published as: AU3763699A

Abstract

This invention is an irrigation sleeve (10), and ultrasonic needle (36) for use with a hand held portion (34) of a phacoemulsification apparatus. The irrigation sleeve (10) includes an irrigation sleeve base portion (12) configured for removable attachment to the hand held portion (34) of the phacoemulsification apparatus; an irrigation sleeve extending portion (14) connected to the base portion (12); and a passageway (16, 54) extending through the base, and extending portions (12, 14). The irrigation sleeve includes an inner wall portion made of a sbstantially rigid material, and an outer coating portion made of a soft resilient material. The ultrasonic needle includes tubular shaft (49) having a longitudinal axis, a distal end (37), a proximal end (45) and a hub connected to the shaft (49) at the distal end.

Description

Title of the Invention

IRRIGATION SLEEVE AND ULTRASONIC NEEDLE FOR PHACOEMULSIFICATION APPARATUS

Field of the Invention

This invention relates to surgical instruments, and more particularly, to improved

irrigation sleeves and ultrasonic needles for use with phacoemulsification apparatus.

Background of the Invention

When the natural lens of the eye no longer functions well, it may be removed and

replaced with, for example, a deformable intraocular lens. Today, the natural lens of the

eye may be removed through a relatively small incision in the eye with the use of phacoemulsification, a process in which the natural lens is disintegrated by the concentrated application of high frequency, low amplitude vibrations via a phacoemulsification needle.

The conventional phacoemulsification apparatus used to remove the natural lens

of the eye has a hand held portion which includes an ultrasonic horn disposed within a cylindrical irrigation head. The distal end of a through bore in the horn is threaded to

receive the threaded proximal end of a replaceable titanium phacoemulsification. needle.

The phacoemulsification needle is provided with a hollow cutting tip. The distal end of

the irrigation head is externally threaded to receive the threaded proximal end of a replaceable irrigation sleeve. When the cutting tip and irrigation sleeve are installed on

the hand held portion of the phacoemulsification apparatus, an irrigation sleeve conduit

is formed by the concentric arrangement of the outer surface of the cutting tip and the inner surface of the irrigation sleeve.

During surgery, the cutting tip and the irrigation sleeve are introduced to the capsule of the eye through a three to five millimeter incision in the outer tissue of the eye. The hand held portion is maneuvered by the surgeon so that the distal end of the cutting tip is brought into contact with the natural lens. The cutting tip is then ultrasonically

vibrated to fragment the natural lens. The resultant natural lens fragments combine with irrigation solution to form an emulsion. A vacuum provided to the through bore of the ultrasonic horn and communicated through the hollow cutting tip aspirates the emulsified lens from the eye.

Throughout the surgical removal of the lens, an irrigating fluid is pumped to the

irrigation head, through the irrigation sleeve conduit and into the eye. The irrigating fluid

pressurizes and inflates the eye and thus counteracts the tendency of the eye to collapse

due to the release of internal pressure through the surgical incision and the removal of the

emulsified lens by vacuum. Further, the irrigating fluid protects the delicate tissues of the

eye from the heat created by the ultrasonic vibration of the cutting tip, and also provides

a suspending fluid for aspirating the emulsified lens. Thus, the supply of irrigating fluid to the eye is of crucial importance to the use of phacoemulsification to remove the natural lens. Indeed, a patient's eyesight is threatened when the flow of irrigation fluid is impeded, or worse, fully blocked during the lens removal procedure. The most common cause of eye injury associated with an interruption in the delivery of irrigation fluid occurs when the force of the ocular incision against the irrigation sleeve causes the inner surface of the extending portion of the

irrigation sleeve to contact the outer surface of the cutting tip, thus occluding the

irrigation sleeve conduit.

To prevent the compression of the irrigation sleeve and the resultant impedance

to the flow of irrigation fluid through the irrigation sleeve conduit, it has been proposed

to slightly enlarge the incision in the ocular tissue to better accommodate the irrigation

sleeve. However, enlarging the ocular incision allows irrigating fluid to rapidly escape from space between the surface of the incision and the outer surface of the irrigation

sleeve. The irrigating fluid is thereby prevented from maintaining the eye in a pressurized and inflated condition.

Other problems associated with the use of phacoemulsification in the eye include

cavitation erosion of the tip of the needle and subsequent deposition of metallic particles

in the eye, the formation of cavitation bubbles which visually interfere with the surgical procedure, and damage to eye tissue caused by excessive heat transfer from the needle. Background information pertaining to phacoemulsification devices including

irrigation sleeves and ultrasonic needles is disclosed in U.S. Patent Nos. 4,787,889 to

Steppe et al, U.S. Patent No. 4,808,154 to Freeman, U.S. Patent No. 5,084,009 to

Mackool, U.S. Patent No. 5,151,084 to Khak, 5,188,584 to Wypych et al, and U.S.

Patent No. 5,505,693 to Mackool. These patent references are incorporated herein by reference to provide the context and environmental use of the irrigation sleeves according

to the present invention.

Summary of the Invention

Accordingly, it is a first object of the present invention to provide an irrigation

sleeve which resists compression.

It is a second object of the present invention to provide an irrigation sleeve which

does not leak at the connection to the irrigation head.

It is a third object at the present invention to provide an irrigation sleeve which

decreases the loss of irrigation fluid at the interface of the irrigation sleeve and the ocular

incision.

It is a fourth object of the present invention to provide an irrigation sleeve which

resists loosening during phacoemulsification. It is a fifth object of the present invention to provide an irrigation sleeve which

dampens ultrasonic vibration transmitted through the irrigation sleeve.

It is a sixth object of the present invention to provide an irrigation sleeve which decreases the amount of cavitation in the irrigating fluid.

It is a seventh object of the present invention to provide an irrigation sleeve which

allows for increased levels of ultrasonic energy to be applied to the cutting tip.

It is an eighth object of the present invention to provide an irrigation sleeve which decreases turbulence of the irrigating fluid.

It is a ninth object of the present invention to provide an irrigation sleeve with

improved cutting tip maneuverability.

It is a tenth object of the present invention to provide an irrigation sleeve which

includes a wall portion made of a substantially rigid material and a coating portion made

of a soft and resilient material.

It is an eleventh object of the present invention to provide an irrigation sleeve

which includes a base portion, an intermediate portion, an extending portion, and a

longitudinal passageway. It is a twelfth object of the present invention to provide an irrigation sleeve which includes a multi-piece irrigation sleeve which is assembled immediately prior to use and allows for different base portion, intermediate portion and extending portion combinations.

It is a thirteenth object of the present invention to provide an irrigation sleeve which includes a base portion and an integral intermediate portion made of a substantially

rigid material coated with a soft and resilient material, and an extending portion made of

a substantially rigid material coated with a soft and resilient material.

It is a fourteenth object of the present invention to provide an irrigation sleeve which includes a base portion and an integral intermediate portion made of a soft and resilient material connected to an extending portion made of a substantially rigid material.

It is a fifteenth object of the present invention to provide an irrigation sleeve

having a base portion and an integral intermediate portion made of silicone and an

extending portion made of polysulfone.

It is a sixteenth object of the present invention to provide an ultrasonic needle

which minimizes the cavitation erosion of the tip and subsequently the deposition of

metallic particles in the eye. It is a seventeenth object of the present invention to provide an ultrasonic needle which reduces undesirable adjacent tissue heating.

It is an eighteenth object of the present invention to provide an ultrasonic needle

which minimizes the production of cavitation bubbles which may visually interfere with the surgical procedure.

It is a nineteenth object of the present invention to provide an irrigation sleeve and

ultrasonic needle combination which achieves the above-listed objects of the irrigation

sleeve and ultrasonic needle.

The present invention is directed to an improved phacoemulsification apparatus,

in particular to an improved irrigation sleeve and ultrasonic needle.

The improved irrigation sleeve according to the present invention is arranged to prevent compression or restriction of the irrigation sleeve conduit, and/or to improve the

seal between the irrigation sleeve and the irrigation head.

One preferred embodiment of the irrigation sleeve according to the present

invention utilizes a base portion made of a soft and resilient material connected to an

extending portion made of a substantially rigid material. For example, a molded silicone base is connected to a polysulfone extending portion. The resilient nature of the silicone base provides a leak-proof seal with the irrigation head while the polysulfone extending portion significantly resists compression.

Another preferred embodiment of the irrigation sleeve according to the present

invention utilizes a substantially rigid irrigation sleeve provided with a soft and resilient

coating portion (e.g., internal threads only, or entire inner surface and/or outer surface).

When the extending portion of this preferred embodiment (utilizing a substantially

rigid irrigation sleeve provided with a soft and resilient coating portion) of the irrigation sleeve of the present invention is placed within an ocular incision, the soft and resilient coating portion, for example, on a wall portion of the extending portion provides a gentle surface which conforms to the contour of the ocular incision to inhibit the loss of irrigation

fluid therefrom. Also, the substantially rigid material of the wall portion of the extending portion prevents the compressive force of the ocular incision from deforming the extending portion such that the inner surface thereof contacts the outer surface of the cutting tip. Further, the combination of the substantially rigid material of the wall portion

at the base portion, and the soft and resilient material of the coating portion on the wall

portion of the base portion prevent leakage and/or loosening of the sleeve at the connection of the irrigation sleeve to the irrigation head.

The ultrasonic needle of the present invention is designed to minimize cavitation

erosion of the tip of the needle, lessen heat transfer to eye tissue surrounding the surgical

site and improve the aspiration flow from the eye through the needle. One embodiment of the ultrasonic needle of the present invention comprises a tubular shaft having a longitudinal axis, a distal end and a proximal end; a wall thickness of the shaft being in the range of about .001 to about .003 inches; and a hub connected

to the shaft at the distal end, the hub comprising a conical portion adjacent the distal end of the shaft, a cylindrical portion having at least one wrenching flat, and a threaded portion; wherein the hub defines a bore having a diameter larger than an inside diameter of the shaft.

Preferably, a transition portion of the bore from the inside diameter of the shaft to

the diameter of the bore is conical in shape.

In a preferred embodiment, the range of the wall thickness of the shaft of the

ultrasonic needle is from about .001 inches to about .0025 inches.

In a most preferred embodiment, the wall thickness of the shaft is about .00175

inches.

Another aspect of the invention is an irrigation sleeve and ultrasonic needle

combination for use with a hand held portion of a phacoemulsification apparatus,

comprising an irrigation sleeve, the irrigation sleeve comprising an irrigation sleeve base portion configured for removable attachment to the hand held portion of the phacoemulsification apparatus; an irrigation sleeve extending portion connected to said base portion; and a passageway extending through said base and extending portions;

wherein said irrigation sleeve includes an inner wall portion made of a substantially rigid

material and an outer coating portion made of a soft and resilient material; and

an ultrasonic needle at least partially disposed in the irrigation sleeve.

In one embodiment of the irrigation sleeve and ultrasonic needle combination the inner wall portion is provided only in the extending portion.

In another embodiment of the irrigation sleeve and ultrasonic needle combination

the inner wall portion defines an inner layer, and said outer coating portion defines a separate outer layer connected to said inner layer, the irrigation sleeve further comprising an inner coating portion made of a soft and resilient material, said inner coating portion

connected to and located on an inner side of said inner wall portion,

Another aspect of the invention is an irrigation sleeve and ultrasonic needle combination for use with a hand held portion of a phacoemulsification apparatus,

comprising an irrigation sleeve, the irrigation sleeve comprising an irrigation sleeve base

portion configured for removable attachment to the hand held portion of the

phacoemulsification apparatus; an irrigation sleeve extending portion connected to said

base portion, said extending portion including an outer layer made of a soft and resilient

material and an inner stiffener made of a substantially rigid material for reinforcing said

outer layer; and a passageway extending through said base and extending portions; and

an ultrasonic needle at least partially disposed in the irrigation sleeve. Yet another aspect of the invention is an irrigation sleeve and ultrasonic needle

comprising an irrigation sleeve, the irrigation sleeve comprising an outer irrigation sleeve

made of a soft and resilient material; and an inner stiffener connected to and located inside said outer irrigation sleeve for reinforcing said irrigation sleeve to prevent collapsing of said outer irrigation sleeve and restriction of flow therethrough; and an ultrasonic needle

at least partially disposed in the irrigation sleeve.

Further objects, features and advantages of the invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawing.

Brief Description of the Drawings

Fig. 1 is a perspective view of a first embodiment of an irrigation sleeve according to the present invention installed on the hand held portion of a conventional phacoemulsification apparatus.

Fig. 2 is a longitudinal cross-sectional view of the assembly shown in Fig. 1.

Fig. 3 is a broken away partial side view of an extending portion of an irrigation sleeve according to the present invention.

11 Fig. 4 is a detailed longitudinal cross-sectional view of a second embodiment of an irrigation sleeve according to the present invention.

Fig. 5 is a detailed transverse cross-sectional view of the assembly as indicated in Fig. 1.

Fig. 6 is a detailed longitudinal cross-sectional view of a third embodiment of an

irrigation sleeve according to the present invention.

Fig. 7 is a broken away detailed cross-sectional view of a fourth embodiment of

an irrigation sleeve according to the present invention.

Fig. 8 is a broken away detailed cross-sectional view of a fifth embodiment of an

irrigation sleeve according to the present invention.

Fig. 9 is a detailed longitudinal cross-sectional view of a sixth embodiment of an

irrigation sleeve according to the present invention installed on the hand held portion of

a conventional phacoemulsification apparatus.

Fig. 10 is a detailed longitudinal cross-sectional view of a seventh embodiment of

an irrigation sleeve according to the present invention.

12 Fig. 11 is a detailed longitudinal cross-sectional view of a eighth embodiment of

an irrigation sleeve according to the present invention.

Fig. 12 is a detailed longitudinal cross-sectional view of an ninth embodiment of an irrigation sleeve according to the present invention.

Fig. 13 is a detailed longitudinal cross-sectional view of a tenth embodiment of an

irrigation sleeve according to the present invention.

Fig. 14 is a detailed longitudinal cross-sectional view of the irrigation sleeve shown

in Fig. 9 installed on the hand held portion of a conventional phacoemulsification

apparatus.

Fig. 15 is a side view of one embodiment of the ultrasonic needle of the invention.

Fig. 16 is an end view of the embodiment of Fig. 15 taken along the line 16-16 of

Fig. 15.

Fig. 17 is a cross-sectional view of the embodiment of Fig. 15 taken along the line 17-17 of Fig. 15.

Fig. 18 is a partial cross-sectional view of a second embodiment of the ultrasonic needle according to the invention.

13 Detailed Description of the Preferred Embodiments

Figs. 1 and 2 show an irrigation sleeve 10 according to the present invention

installed on the hand held portion 50 of a conventional phacoemulsification apparatus.

The irrigation sleeve 10 is made of a substantially rigid plastic material resistant to

deformation. Specifically, the irrigation sleeve 10 is made of a substantially rigid plastic

material that resists inwardly directed compression from the eye incision that would tend to pinch the irrigation sleeve against the needle and restrict the flow of irrigation fluid during use. Preferred plastic materials include polyolefins, in particular polyethylene and polypropylene. However, these materials have melting points close to the temperature and pressure required for autoclaving. Thus, polyolefins are particularly suitable for one time use (i.e., disposable) applications. More preferred plastic materials including

polysulfone, polycarbonate, polyimide, and polyetherimide, provide irrigation sleeves that

can be sterilized by autoclaving.

Importantly, the irrigation sleeve 10 is designed or configured to tightly seal with

the hand held portion 50 of the phacoemulsification apparatus, even though the irrigation

sleeve 10 is made of substantially rigid plastic material compared to conventional silicone irrigation sleeves, and without a separate sealing component (e.g., "O" ring). For

example, the internal threads of the irrigation sleeve 10 can be made slightly undersized,

or the thread design can be modified to cause one or more threads to undergo resilient or

permanent deformation to provide a sealing function with the external threads of the

14 handheld portion of the phacoemulsification apparatus. Alternatively, an additional

internal integral seal (e.g., ring) can be molded into the irrigation sleeve 10 to cause sealing engagement with the hand held portion of the phacoemulsification apparatus, while providing a one-piece molded design of the irrigation sleeve. Further, an adhesive and/or sealing composition (e.g., silicone sealant) can be provided (e.g., coated) on the integral

threads of the irrigation sleeve to enhance sealing with the external threads of the hand

held portion of the phacoemulsification apparatus.

The hand held portion 50 of the conventional phacoemulsification apparatus

includes an ultrasonic horn 34 disposed within a cylindrical irrigation head 38. The distal

end 41 of a through bore 35 in horn 34 includes an internally threaded portion 39a which engages the externally threaded portion 39b of the proximal end 45 of a replaceable

hollow cutting tip 36 (i.e., phacoemulsification needle).

The distal end 47 of irrigation head 38 is configured for receiving the proximal end

28 of irrigation sleeve 10. In the preferred embodiment shown, the inner surface 44 of the

base portion 12 of irrigation sleeve 10 includes an internally threaded portion 26 which

engages an externally threaded portion 42 of the distal end 47 of irrigation head 38. Other

arrangements may be used for attaching irrigation sleeve 10 to irrigation head 38. For

example, base portion 12 may be attached to irrigation head 38 by a compression fit.

In the embodiment shown in Figs 1 and 2, the outer surface 52 of irrigation sleeve

10 along base portion 12 is cylindrically shaped. However, outer surface 52 may be other

15 shapes. For example, outer surface 52 may define a substantially conical shape. Further,

the transverse cross-sectional shape of outer surface 52 is smooth and circular. However,

the transverse cross-sectional shape of outer surface 52 of base portion 12 may define

other shapes and textures. For example, the transverse cross-sectional shape of outer surface 52 of base portion 12 may define a hexagonal shape, or a knurled surface for

mounting, by tool or by hands, respectfully, irrigation sleeve 10 onto irrigation head 38.

The base portion 12 of the irrigation sleeve 10 connects to an intermediate portion

22, and an extending portion 14 which extends towards, but terminates short of, the distal

end of cutting tip 36. The outer surface 52 of the irrigation sleeve 10 at the intermediate

portion 22 and extending portion 14 is conical. However, the outer surface 52 may define

a series of stepped components which define other shapes. For example, outer surface 52

may be cylindrically shaped along intermediate portion 22 and conically shaped along

extending portion 14. Further, base portion 12 may transition directly to extending

portion 14 with no intermediate portion 22 therebetween.

The inner surface 44 of base portion 12, intermediate portion 22, and extending

portion 14 forms a passageway 16 along the longitudinal axis of irrigation sleeve 10. In

the embodiment shown in Figs. 1-2, the longitudinal cross-sectional of inner surface 44

substantially parallels the shape of the outer surface 52 of irrigation sleeve 10. However,

the base portion 12, intermediate portion 22, and extending portion 14 may be configured

so that the longitudinal cross-section of inner surface 44 defines a variety of different

shaped passageways along the longitudinal axis of irrigation sleeve 10. For example, in

16 an alternative embodiment shown in Fig. 3, a portion of the longitudinal cross-section of

inner surface 44' within extending portion 14' may taper inwardly, and define a section

of a cone having an angle «, (e.g., two (2) degrees) relative to the longitudinal axis of

irrigation sleeve 10. The longitudinal cross-section of outer surface 52' of extending

portion 14' may define a section of a cylinder, and may be oriented parallel to the

longitudinal axis of the irrigation sleeve 10.

In the embodiment shown in Figs. 1 -2, the transverse cross-section of inner surface

44 defines a circle. However, the transverse cross-section of inner surface 44 may have

other suitable shapes, including, for example, a polygonal shape, an elliptical shape or

other shapes. Inner surface 44 may also be configured to include such features as rifling,

texturing (e.g., ridged or bumped), or other suitable configurations.

The concentric arrangement of the outer surface of the horn 34 and the inner

surface of the irrigation head 38 forms an annular irrigation head conduit 40 as shown in

Fig. 2. Annular irrigation head conduit 40 communicates to the entrance 46 of an

irrigation sleeve conduit 54 formed by the outer surface of cutting tip 36 and the inner

surface 44 of irrigation sleeve 10. In the embodiment shown in Figs. 1 and 2, the cross-

sectional area of conduit 54 decreases from entrance 46 to an exit 48 located at the distal

end 32 of irrigation sleeve 10.

17 During surgery, extending portion 14 of irrigation sleeve 10 and cutting tip 36 are introduced to the capsule of the eye through a 0.5 to 5 millimeter (mm) incision in the

outer tissue of the eye. Irrigating fluid is pumped through annular conduit 40 and

irrigation sleeve conduit 54 into the surgical site from exit 48. When the cutting tip 36 is

sufficiently proximal to the natural lens, the ultrasonic horn 34 is activated causing the

ultrasonic vibration of the cutting tip 36 which emulsifies the natural lens. The remnants

of the natural lens and the irrigation fluid in which the remnants of the lens are suspended

are removed from the eye through the open distal end 37 of hollow cutting tip 36 by a

vacuum provided to tip 36 via through bore 35 in ultrasonic horn 34.

Fig. 4 shows a second embodiment of an irrigation sleeve 110. Irrigation sleeve

110 includes a wall portion 120 made of a substantially rigid material, for example

polysulfone, and a coating portion 124 made of a soft and resilient material such as

silicone. In the embodiment shown in Fig. 4, wall portion 120 is continuous and coating

portion 124 is applied uniformly to wall portion 120.

The substantially rigid material of wall portion 120 prevents improper deformation

of irrigation sleeve 110 and the soft and resilient material of coating portion 124 provides

an improved surface for irrigation sleeve 110. For example, when the distal end 132 of

extending portion 114 of irrigation sleeve 110 is inserted through the ocular incision, wall

portion 120 prevents extending portion 114 from splaying, folding outwardly or wrinkling

in an accordion-like manner along outer surface 152 of cutting tip 136. Further, coating

18 portion 124 prevents the distal end 132 of extending portion 114 from cutting into or

otherwise damaging the ocular tissues as the cutting tip 136 and irrigation sleeve 110 are

passed therethrough.

While extending portion 114 of irrigation sleeve 110 is within the ocular incision,

wall portion 120 prevents the inner surface 144 of extending portion 114 from contacting

the outer surface of cutting tip 136. Wall portion 120 also prevents the radial and

longitudinal expansion or contraction of the irrigation sleeve 110 due to forces such as

fluctuation in fluid pressure at the irrigation head 138 or forces associated with the

maneuvering of the irrigation sleeve 110 and cutting tip 136 within the eye. Because wall

portion 120 resists deformation, in particular, those types of deformation which greatly

disturb the inner surface 144 of irrigation sleeve 110, the flow of irrigation fluid to the eye

is maintained in a substantially non-turbulent or laminar state.

Also, during insertion and while within the eye, coating portion 124 deforms

according to the contour of the ocular incision to inhibit the loss of irrigation fluid at the

interface between the outer surface 152 of the extending portion 114 of the irrigation

sleeve 110 and the surface of the ocular incision. Further, coating portion 124 at the

threaded portion 126 of base portion 112 engages the threaded surface of the irrigation

head to prevent irrigating fluid from leaking at the connection therebetween and also to

prevent the irrigation sleeve from becoming loose during phacoemulsification. Coating

portion 124 dampens ultrasonic vibration transmitted form the inner surface 144 and the

outer surface 152 of the cutting tip during phacoemulsification. Cavitation is thereby

19 inhibited in the irrigating fluid thus improving the surgeon's view of the surgical site.

Furthermore, because of the improved vibration damping, power may be increased to

ultrasonic horn 134 and cutting tip 136 without damaging surrounding ocular tissue.

Preferably, materials of low thermal conductivity are used to make wall portion

120 and coating portion 124 so that the transfer of potentially damaging heat to the ocular

tissue is inhibited. Those of ordinary skill in the art can readily select and employ suitable materials of low thermal conductivity. Further, embodiments of irrigation sleeve 110

having multiple internal boundaries provide improved vibration damping and heat insulating properties over embodiments including only one or no internal boundary.

An irrigation sleeve according to the present invention may also include a wall

portion which is continuous or intermittent throughout any portion of the irrigation sleeve.

For example, in a third alternative embodiment of the present invention shown in Fig. 6,

wall portion 220 is made of a series of ribs 220. Multiple continuous wall portions may also be included in irrigation sleeve. For example, in the partial broken away view of

extending portion 314 of the fourth alternative embodiment of irrigation sleeve 310 shown

in Fig. 7, a central corrugated wall portion 320a is enveloped by outer wall portions 320b.

Coating portion 124 may also be configured to be continuous or intermittent on

any portion of irrigation sleeve 110. For example, coating portion 124 might be provided

only on the threaded surface 126 of base portion 112 and/or on the outer surface 152 of

extending portion 114.

20 Since coating portion 124 may be configured to provide a smooth inner surface

144 and a smooth outer surface 152, any feature included in wall portion 120 for

improving the heat insulating properties, vibration dampening properties, or other measure of performance of irrigation sleeve 110 is prevented from posing a threat of injury to the

tissue of the eye. For example, the longitudinal or transverse cross-section of wall portion

420 may define a relatively high frequency saw tooth wave, or other non-smooth profile,

whereas the longitudinal and transverse cross-section on inner surface 444 and outer

surface 452 may be smooth, as shown in Fig. 8.

In other alternative embodiments of the present invention, the soft and resilient material of coating portion 124 may be included in a structural component of irrigation

sleeve 510 independently of the substantially rigid (i.e., resists deformation) material of

wall portion 520. For example, in a sixth embodiment of the present invention shown in

Fig. 9, base portion 512 and intermediate portion 522 are made of a soft and resilient

material and extending portion 514 is made of a substantially rigid material.

In embodiments where a soft and resilient material is included as a structural

component independent of the substantially rigid material of wall portion 20, a means for

connecting components made of different materials is included in the irrigation sleeve. For

example, in the embodiment shown in Fig. 9, the interior surface 544 of irrigation sleeve

510 at the distal end of intermediate portion 522 includes a circumferential channel 562

for receiving a flange 564 at the proximal end of extending portion 514. It is important

to note that the connection formed by flange 564 and circumferential channel 562 further

21 inhibits the transmission of ultrasonic vibration to extending portion 514 and thus provides

an irrigation sleeve 510 with improved vibration dampening properties.

A seventh embodiment of irrigation sleeve 610, shown in Fig. 10, is identical to that shown in Fig. 9 except that in the place of a flange and channel connection, extending

portion 614 is connected to intermediate portion 622 by an adhesive 666. Alternatively,

or in addition to other forms of connection, a sonic weld may be used to connect

extending portion 614 to intermediate portion 622.

An eighth embodiment of an irrigation sleeve 710 according to the present

invention is shown in Fig. 11. Irrigation sleeve 710 includes a first base portion 712a,

made of a soft and resilient material. First base portion 712a includes a groove 768 in the

distal end thereof which is parallel to the longitudinal axis of the irrigation sleeve 710.

Groove 768 is configured to receive a tongue 772 on the proximal end of a second base

portion 712b. Second base portion 712b is made of a substantially rigid material. Second

base portion 712b includes a conical shaped intermediate portion 722 and cylindrical

extending portion 714, both also made of a substantially rigid material. Further, securing

means, such as an adhesive or a barb and catch assembly, may be provided on tongue 772

for further securing second base portion 712b to first base portion 712a.

A ninth embodiment of an irrigation sleeve 810 according to the present invention, shown in Fig. 12, includes a conical extending portion 814. The outer surface 852 at the proximal end of conical extending portion 814 engages the inner surface 844 of

22 intermediate portion 822. In a tenth embodiment of irrigation sleeve 910 shown in Fig.

13, the inner surface 944 at the proximal end of conical extending portion 914 engages

the outer surface 952 of intermediate portion 922. In the embodiments shown in Figs.

12 and 13, extending portion 814 and 914, respectfully, is made of a substantially rigid

material and base portion 812 (912) with integral intermediate portion 822 (922) is made

of a soft and resilient material (e.g., a flexible sealing material). Also, a means of sealing, such as an adhesive, is included at the connection between extending portion 814 (914)

and intermediate portion 822 (922).

During use, cutting tip 136 and extending portion 114 of the irrigation sleeve 110

are constantly maneuvered within the eye. Trauma to the ocular tissue is caused by the

frictional contact between the small ocular incision and extending portion 114 during this

movement. To alleviate or prevent some of this trauma and also to improve the

maneuverability of the irrigation sleeve 110, irrigation sleeve 110 may be configured to

move relative to cutting tip 136. In the embodiment shown in Fig. 9, relative rotational

movement between extending portion 514 and intermediate portion 522 is provided by

increasing the volume of channel 562, thus allowing flange 564 to "float" within channel

562.

Maneuverability of cutting tip 136 may be further improved by the inclusion of

means for allowing a predetermined amount of relative movement, or "play", between

extending portion 114 and the rest of irrigation sleeve 110. For example, as shown in Fig.

14, the soft and resilient material of base portion 1012 and intermediate portion 1022 may

23 be configured to elastically deform to create an angle, «', between the longitudinal axis of

the cutting tip 1036 and the normally collinear longitudinal axis of the extending portion

1014. Further, intermediate portion 1022 may be configured to elastically deform to

create a change in distance, d, between the distal end 1037 of the cutting tip 1036 and the

distal end 1032 of the irrigation sleeve 1010.

Further, the irrigation sleeve 1010 shown in Fig. 14 may be configured as part of

a kit. During use of the kit in surgery, the surgeon chooses various combination of kit components to be connected in order to achieve desired characteristics of irrigation sleeve 1010. For example, a kit including a base portion 1012 with an integral intermediate

portion 1022 may include separate extending portions 1014 of various diameters and

lengths. After selecting desired components, the surgeon connects extending portion

1014 to base portion 1012 by placing the distal end of extending portion 1014 at the

proximal end 1028 of passageway 1016. Extending portion 1014 is then pushed through

base portion 1012 until the flange 1064 at the proximal end of the extending portion 1014

engages channel 1062 in intermediate portion 1022.

Figs. 15-17 show a first embodiment of the ultrasonic needle 60 of the invention.

The needle 60 is made from, for example, titanium or stainless steel. A preferred material

for the needle 60 is 6AL4V titanium. The surface of the needle 60 is finished to a

roughness of, for example, 16 R.M.S.

24 As shown in Figs. 15-17, the ultrasonic needle 60 includes a tubular shaft 62 having a wall 64. The thickness of the wall 64 is much less than prior art needles. The thickness of the wall 64 is in the range of about .001 to about .003 inches. Preferably, the

thickness of the wall 64 is from about .001 to about .0025 inches. Most preferably, the

thickness of the wall 64 is about .00175 inches.

The thin wall of the needle 60 contributes to several advantages of the invention.

For example, the thin-walled needle 60 generates less heat thereby lessening the possibility

of damage to surrounding eye tissue. The thin-walled needle 60 is a more efficiently

transfers energy from the ultrasonic horn to the surgical site. Also, because there is less

metal mass moving, less energy is required to overcome the inertial forces of the needle 60.

Another advantage of the thin- walled needle 60 is that the displacement of the tip

86 is increased. If the needle 60 is conceptualized as a mechanical beam, the decrease in wall thickness results in a weaker beam and, consequently, greater displacement at the end

of the beam, that is, the tip of the needle 60. The greater tip displacement means that, for

a single position of the handheld phacoemulsification apparatus, the tip of the needle 60

will radiate over a larger area and the shock waves which emanate from the tip of the

needle 60 will radiate over a larger area. Thus, the surgeon will not need to maneuver the

handheld apparatus as much as with devices that have less tip displacement.

25 The distal end of the tubular shaft 62 is connected to a hub 66. The hub 66

comprises three portions: a conical portion 68, a cylindrical portion 70 and a threaded

portion 74. The conical portion 68 extends from the distal end of the tubular shaft 62 to

the cylindrical portion 70. A particular advantage of the conical portion 68 is that it helps

to eliminate cavitation bubbles. Cavitation bubbles are undesirable for at least two reasons. First, cavitation bubbles can erode the tip of the needle 60 and subsequently,

deposit metallic particles in the eye. Additionally, cavitation bubbles can visually interfere

with the surgical procedure. The conical portion 68 is also more effective in transmitting

ultrasonic vibrations through the needle 60, as compared to prior art designs.

Cylindrical portion 70 extends from the conical portion 68 to the threaded portion

74. Cylindrical portion 70 includes at least one wrenching flat 72 for attaching the needle

60 to an ultrasonic horn.

Threaded portion 74 includes an annular flange 76 which serves as a stop when

the needle 60 is threaded into the ultrasonic horn. Threaded portion 74 includes external

threads 75 for engaging internal threads of an ultrasonic horn. The needle 60 is attached

to an ultrasonic horn in the same manner as the needle 36 shown in Fig. 2.

As shown in Fig. 17, the hub 66 includes a bore 78 having a diameter 80. The

diameter 80 of the bore 78 is larger than the diameter 82 of the tubular shaft 62. The

increased diameter of the bore 78 offers less resistance to the aspiration flow from the tip

26 86 of the needle through the shaft 62. The increased diameter of the bore 78 helps to

increase the aspiration flow rate and helps prevent clogging of the shaft 62.

In a second embodiment of the inventive needle 60, shown in Fig. 18, the

transition 84 from the interior of the tubular shaft 62 to the full diameter 80 of the bore

78 is conical in shape. The conical transition 84 is advantageous for several reasons. First, it increases the portion of the aspiration flow path that has a diameter larger than the

inner diameter of the tubular shaft. The increased diameter of the transition portion 84

contributes to better aspiration flow for the reasons discussed above with regard to the

larger diameter of the bore 78. Second, the inner conical transition 84 helps to

concentrate the ultrasonic energy at the tip 86 of the shaft. When more energy is

concentrated at the tip 86, less energy is absorbed by the needle 60 and, consequently, less

unwanted heat is generated by the needle 60.

Because of the efficient energy transfer design of the ultrasonic needle 60 of the

present invention, it may be used at a variety of ultrasonic frequencies including, for

example, 40kHz and 57kHz.

While the invention has been described with reference to certain preferred

embodiments, numerous changes, alterations and modifications to the described

embodiments are possible without departing from the spirit and scope of the invention as

defined in the appended claims, and equivalents thereof.

27

Claims

I CLAIM:

1. A ultrasonic needle for use with a hand held portion of a phacoemulsification

apparatus, said needle comprising:

a tubular shaft having a longitudinal axis, a distal end and a proximal end; a wall thickness of the shaft being in the range of about .001 to about .003 inches; and

a hub connected to the shaft at the distal end, the hub comprising a conical portion

adjacent the distal end of the shaft, a cylindrical portion having at least one wrenching flat,

and a threaded portion;

wherein the hub defines a bore having a diameter larger than an inside diameter of the shaft and wherein a transition portion of the bore from the inside diameter of the shaft

to the diameter of the bore is conical in shape.

2. The ultrasonic needle of claim 1 wherein the range of the wall thickness of the

shaft is from about .001 inches to about .0025 inches.

3. The ultrasonic needle of claim 2 wherein the wall thickness of the shaft is about

.00175 inches.

4. An irrigation sleeve and ultrasonic needle combination for use with a hand held portion of a phacoemulsification apparatus, comprising:

28 an irrigation sleeve, the irrigation sleeve comprising:

an irrigation sleeve base portion configured for removable attachment to the hand held portion of the phacoemulsification apparatus;

an irrigation sleeve extending portion connected to said base portion;

and

a passageway extending through said base and extending portions;

wherein said irrigation sleeve includes an inner wall portion made of a

substantially rigid material and an outer coating portion made of a soft and resilient material: and

an ultrasonic needle at least partially disposed in the irrigation sleeve.

5. The irrigation sleeve and ultrasonic needle combination of claim 4 wherein the

ultrasonic needle comprises:

a tubular shaft having a longitudinal axis, a distal end and a proximal end; a wall

thickness of the shaft being in the range of about .001 to about .003 inches; and

29 a hub connected to the shaft at the distal end, the hub comprising a conical portion

and a threaded portion;

wherein the hub defines a bore having a diameter larger than an inside diameter of

the shaft.

6. The irrigation sleeve and ultrasonic needle combination of claim 5 wherein a transition portion of the bore from the inside diameter of the shaft to the diameter of the

bore is conical in shape.

7. The irrigation sleeve and ultrasonic needle combination of claim 5 wherein the

range of the wall thickness of the shaft is from about .001 inches to about .0025 inches.

8. The irrigation sleeve and ultrasonic needle combination of claim 7 wherein the wall

thickness of the shaft is about .00175 inches.

9. The irrigation sleeve and ultrasonic needle combination of claim 4, wherein said inner wall portion is provided only in said extending portion.

10. The irrigation sleeve and ultrasonic needle combination of claim 9 wherein the

ultrasonic needle comprises:

30 a tubular shaft having a longitudinal axis, a distal end and a proximal end; a wall thickness of the shaft being in the range of about .001 to about .003 inches; and

a hub connected to the shaft at the distal end, the hub comprising a conical portion adjacent the distal end of the shaft, a cylindrical portion having at least one wrenching flat

and a threaded portion;

wherein the hub defines a bore having a diameter larger than an inside diameter of the shaft.

11. The irrigation sleeve and ultrasonic needle combination of claim 10 wherein a transition portion of the bore from the inside diameter of the shaft to the diameter of the

bore is conical in shape.

12. The irrigation sleeve and ultrasonic needle combination of claim 10 wherein the

13. The irrigation sleeve and ultrasonic needle combination of claim 12 wherein the

wall thickness of the shaft is about .00175 inches.

14. The irrigation sleeve and ultrasonic needle combination of claim 4 wherein said

inner wall portion defines an inner layer, and said outer coating portion defines a separate outer layer connected to said inner layer, the irrigation sleeve further comprising an inner

31 coating portion made of a soft and resilient material, said inner coating portion connected

to and located on an inner side of said inner wall portion.

15. The irrigation sleeve and ultrasonic needle combination of claim 14 wherein the ultrasonic needle comprises:

adjacent the distal end of the shaft, a cylindrical portion having at least one wrenching flat

and a threaded portion; wherein the hub defines a bore having a diameter larger than an

inside diameter of the shaft.

16. The irrigation sleeve and ultrasonic needle combination of claim 15 wherein a transition portion of the bore from the inside diameter of the shaft to the diameter of the

bore is conical in shape.

17. The irrigation sleeve and ultrasonic needle combination of claim 15 wherein the

18. The irrigation sleeve and ultrasonic needle combination of claim 17 wherein the

wall thickness of the shaft is about .00175 inches.

32

19. An irrigation sleeve and ultrasonic needle combination for use with a hand held portion of a phacoemulsification apparatus, comprising:

an irrigation sleeve, the irrigation sleeve comprising

an irrigation sleeve base portion configured for removable attachment

to the hand held portion of the phacoemulsification apparatus;

an irrigation sleeve extending portion connected to said base portion,

said extending portion including an outer layer made of a soft and resilient material and an inner stiffener made of a substantially rigid material for reinforcing said outer layer; and

a passageway extending through said base and extending portions; and

an ultrasonic needle at least partially disposed in the irrigation sleeve.

20. The irrigation sleeve and ultrasonic needle combination of claim 19 wherein the ultrasonic needle comprises:

33 a hub connected to the shaft at the distal end, the hub comprising a conical portion

adjacent the distal end of the shaft, a cylindrical portion having at least one wrenching flat and a threaded portion;

21. The irrigation sleeve and ultrasonic needle combination of claim 20 wherein a

transition portion of the bore from the inside diameter of the shaft to the diameter of the bore is conical in shape.

22. The irrigation sleeve and ultrasonic needle combination of claim 20 wherein the range of the wall thickness of the shaft is from about .001 inches to about .0025 inches.

23. The irrigation sleeve and ultrasonic needle combination of claim 22 wherein the

wall thickness of the shaft is about .00175 inches.

24. An irrigation sleeve and ultrasonic needle combination for use with a hand held

portion of a phacoemulsification apparatus, comprising:

an irrigation sleeve, the irrigation sleeve comprising:

34 an outer irrigation sleeve made of a soft and resilient material; and

an inner stiffener connected to and located inside said outer irrigation sleeve for reinforcing said irrigation sleeve to prevent collapsing of said outer irrigation sleeve and restriction of flow therethrough; and

an ultrasonic needle at least partially disposed in the irrigation sleeve.

25. The irrigation sleeve and ultrasonic needle combination of claim 24 wherein the

ultrasonic needle comprises:

and a threaded portion;

35

26. The irrigation sleeve and ultrasonic needle combination of claim 25 wherein a transition portion of the bore from the inside diameter of the shaft to the diameter of the bore is conical in shape.

27. The irrigation sleeve and ultrasonic needle combination of claim 25 wherein the

28. The irrigation sleeve and ultrasonic needle combination of claim 27 wherein the wall thickness of the shaft is about .00175 inches.

36