CA2136352A1 - Removal of tissue - Google Patents

Abstract

This is a surgical instrument designed to reduce damage to surrounding tissue while fragmenting tissue intended to be removed. The instrument includes a fragmenting tip (14C) connected to a hand piece (10C) by an aspirating tube (18C). The tip (14C) is rotated by a rotational motor (40D) and reciprocated ultrasonically by an ultrasonic vibrator (40C) simultaneously so that tissue is fragmented by the combined motion of a fragmenting surface perpendicular to the surface and at an angle to the surface during rotation. The method can be used for example in cataract removal surgery where the lens is fragmented and removed without damaging the capsular wall or during bypass surgery for freeing the artery or vein to be transplanted without damaging the artery or vein walls.

Description

( W094/~ll~ 2 1 ~ fi 3 ~ 2 rcT~ss4lo3~

REMOVAL OF TISSUE

RELATED CASE
This application is a continuation-in-part of United States application 07f75g,937, filed September 16, 1991t which is a continuation-in-part of United States application 07/680,292, filed April 4, 1991, which is a continuation-in-part of United St~tes application 07/5S3,975 filed in the name o~
Aziz Y. Anis on July 17, 1990, for Remo~al o Tissue.

: ~ : BACKGROUND OF THE INVENTION
~: This invention relate to the re.moval of tissue from the body such as for example re~oval of cataracts ~rom the eye.
; 15 It is known to remove dLseased tissue ~rom the:
body by ~ragmenting, crushing or otherwise making ;~
: the tissue: flowable while in thP. body and then aspirating it. In one Xnown class of surgical techniques of this type specifically intended for ; : 20 ~ ~ the::removal of cataracts ; (l)~ an Lncision Ls made ~ along~the superLor orneal:margin~ from about~ lo to 2 W094~11~ PCT~594/034~ _ ~13~'3S~j ' o'cloc~ tl2 o'clock is the location closest to the top of the head of the patient) approximately 10 mm in chord length; ~2) an incision is made in the caps~lar wall; and (3) the catar~ct is removed. The anterior chamber is maintained substantially ~ormed during the operation by means of a continuous inf low o~ irrigating solution. `.
In one prior art technique of this class for removing a ca~aract, the nucleus is expressed out of the eye and the cortex is removed by a process of irrigation and aspiration. In another prior art .
technique o~ thls class for removing the cataractr the nucleus i5 removed with a vectis and about O.1 millili~er of viscoelastic compound or irrigatiny : 15 fluid is introduced into the capsular bag to separate the capsular walls. With the capsul~r walls separated, a wedge o~ the cortex is engaged in the aspiration port of a cannula and peeled toward the center a~d then aspirated to remove it. This process is repeated so that the layers of the cortex :~
are peeled and then aspirated inw~rdly ~hrough the : cannula, layer by layer, until the intact capsular bag (except for the hori~ontal incision) is completely ~mpty and cl~3an.
: : :

- ~ :

-WO~4/211~ ~ 3 6 3 5 2 PCT~Sg4/03~K
- I

, This technique o~ r-moving the cataract is disclosed by Anis, Aziz Y., "Illustrated Step-by-Step Description o~ the Anis Dry Extra Capsular Catarac~ Extraction Technique With In--the-Bag Lens Implementationi'; Seminars ~n Opthalmology, v. 1, N.

2 (June), 1986, pp. 113-129 and the technique ~s.
compared with other such techniques of this class.
Two pri~r art types of instruments which aid in the fragmenkation and aspiration of the lens nucleus to permit extra~tion through a small incision are disclosed in United States patent 3,5~9,363 to Anton BanXo et al.; United States patent 3,902,495 to Steven ~. Weiss; United States patent 3,693,613 to Charles ~elman et al ~; ~nd United States : patent ,~ :
4,041,947::~o Steven N. Weiss et al. This:instrument i5 intended ~in the prior art to fraqm~nt a lens :
, nucl~us using ultrasonic vibrations to aid ~he :~` irri~tion/aspiration o~ the lens. The u~trasonic vibrations ~laterally reciprocate the tip of an instrument to fracture the ca~aract after which it can'be aspirated.
A further type of instrument is disclosed in : Unit:ed :~States:~patent 4;j908,015 issued: to Anis on March~:13:,:~199~0. This: patent describ-es`an instrument ,- ~

W094/~tl~ 63~ 2 PC1~594/03~

w~ich rotates a solid member h~ving blades extending from it to grind the lens~
These tissue removal techniques hav~ several d~qadvantage~, ~uch as: (1) they ris~ tearing the capsular wall with the re~iprocating ultrasonic ¦ vibration tools or with the rotating blades; (2) under some circumstances, ~hey require large incisions in or removal of parts of the capsular wall; and t3) they may require the use of several ¦ 10 different instruments.
¦ Still another type of prior art technique for removing cataracts is disclosed in United States patent 3t996,935 to Banko issued December 14, 1976~
This type o~ instrument shows cooperating jaw-like members, one of which rotates inside the other to break up the lens by shearing secti.ons o~ it. It aspirates fragments through the instrument. This type of instrument has a disadvantage in that it can brea~ the capsular wall and is relatively complex~
~o Part of the disad~antage comes from the teaching 'I that it may be rotated manually or mechanically wi~hout~a corresponding teachin~ of t~e rate of rotation required for efficien~ use.
Still another prior art instru~ent includes a small~ rotary magnetic cutter that is inj~cted : ~ 4 .

W094/211~ PCT~S94103~
213635~

through t~e capsular wall ~nd a means for applying magnetic fields that control the magnetic cutter i~
position. The small magnetic cutter is ~otated as it mo~es from position to position in the capsular bag and to abrade or cut the lens that iB to be removed.
This instrument has several disadvantages, s~ch as: (l) it is relativPly complicated and expensiYe -because of the need to remotely control the small cutter; and (2) does not incorporate any mechanism ~or aspirating ~the lens particle~ as they are . abraded from the lens.
:: In still another prior art detrice disclosed in U.S. patent 4,002~169, small retractable wires are : 15 rotated in a range of ~ rpm to 16,000 rpm. There is no teachi~g of selecting the speed for s~r~ace discrimination and the device relies on blunt surfaces to avoid damage to the capsular wall instead. ~ This device has the disadvantages of: (1) providing a relatiYely slow cutting velocity range wlth~b~ades not shaped ~or cavitation or turbulance;
: t2) not providing a range of velocities sufficient t~form small particles ~that can be aspirated through a small hole; and (3~ not providing for .

.

.
~-;
~ : 5 ' , ~ }

i, ~spira~ion during fragmenting, thus blocking ! visibility with particl~s.
`~

SUM~ARY OF THE INVENTION
Accordingly, it is an object of the invention to provide a novel technique for tissue removal.
It is a fur~her ob~ect of the invention to provide a novel instrument fcr fragmenting and removing a cataract during cataract removal sllrgery with low risk of damage to the capsular wall, It is a still further object of the invention to provide a novel instrument designed to fragment tissue without damage to the nearby ~ issue such as f~r example not damaging the capsular wall while . dil remo~ing the lens during cataract remo~al surgery or not damaging artery or vein walls while rem~ving cancerous tissue near the vein or artery.
In accordance with the above and further objects of the invention, an incision is made for the insertion of a surface-discriminating ! 1:~ I 20 ~ fragmenting tool. The surface-diciicriminating fragmen~ing tool fragments and permits aspiration o ` high mass, rou~h surface, rigid tissue w~thout damaging nearby smooth, flexible, 1QW mass walls.
: The tool ~ragments some tissue but avoids : :

"

21~6352 fragmenting other ti~sue by discriminating between tissues. This dlscrimination is based on one or more of several i~actors including: ( 1 ) the rigidity of the tissue; (2) thei amoun~ of mass of the tissue;
( 3 ) thei angle of the tissue to the direction o~
movement of ths tool; ( 4 ) the roughness of the sur~ace of the tissue; and ~5~ the size and shape of - the surface o~ the tissuei to the extent the size and shape af f ect the tendency of the negative pressure created by aspiration and/or irrigation tQ move the tissue toward the surface-discriminating fragmenting tool .
~rhe sur~ace discrimination of the tool is controlled by moving ~rfacies which fragment lS diseased tissue on impact, referred to as phacotmes i s, and cause cavitation f orces that further fragment and mix fragments o~ tissue, re~erred to as phacocoelosis, but which move at a rate of speed slow enough so that the more integrated, more f lexible, lower mass and smoo~her tissue is moved away without fragmenting. The tissue is not constrained by opposed shear forces of the tool as in some prior art rotating tools nor is the higher mass, ri~id tissue mo~red signif icantly as a bulX.

:~ 7 s ~ ' . I
W094/211~35~ PCT~s94/03~r The surfaces of the instrument fragment tissue that: ~l) is stiffer and has a highPr modulus of riyidity; and (2) is at an angle to the cutting edge closer to 90 degrees and raceives less force moving 5it away. Thus, the surgeon removing a cataract adjusts ~he speed of mo~ement o~ the tool surfaces aspirating and irriga~ion ~orc~s, rake angle of the leading edge and cavitation level as controlled by position of tool surface, velocity and shape of 10moving surface, especially the trailin~ edge. The adjustment is made to fra~ment the cortex because of its higher mass, modulus of elasticity and projections in the path of the tool surfaces but to move the capsular wall. because of its lower mass, 15lower modulus a~d fewer projections closer to 90 degrees and not fra~ment it.
In one embodiment, a moving fxagmenting sur~ace moves at an angle with the normal to a cataract : sur~ace, which angle i5 obtuse and generally close 20t~ bein~ p~rpendicular to the normal in such a manner as to cause cavitation at its trailing edge t~ aid in fragmenting and mixing the cataract ~particles while maintaining the direct force on t~e cataract relatively low. In a preferred embodiment, : 25the fragmenting surface is moved ultrasonically ,t ,.
,.

: 5 ~ ' . WO94/211~ 213 63 52 PCT~S94/034~

., i~
along the normal while it is moving at an angle to the normal such as by rotating.
In an embodiment having a rotating tip that move3 the cuttin~ edg~, the asplrak~on pressure i8 more e~fective within the moving surfaces of the rotating tip. It ~s low enough to pull the fragmented tissue and tissue to be fragmented but does not hold the smooth flexible capsular wall against mo~ement away from the moving surfa~es of the tool. The rotating surfaces move the smooth wall outwardly and provide some counter pressure to the aspirating pressure inside the fragmenting zoner In one embodiment, radially inwardly extending edges further pu11 and mix tissue within the fragmenting zone~
In the case of cataract removal sur~ery, a small incision of 2 to 7 millimeters a~d preferably 3 millimeters is made in the sclera along the corneal border at 12 o'c}ock and another incision of ¦ 20 similar dimension or a round hole in the anterior ` capsular wall. The instrument is inserted and fragments the~ lens matter without fragmenting the capsular wall, In one embodiment, the surface-discrimlnatingr ~ 25 fragmentiny handpiece includes a shaft with an !~ :

~ ~ .

W094~11~ ~13 ~ 3 5 ~ PCT~594103~ ¦

aspirating port in it within one or more rotating rings or loops or curved sections of a cylinder.
The rotation is at a sufficient ~peed and the area of the open spaces between the fragmenting edges sufficiently small so that relatively smooth intact, flexible, low-inertia tissue such as the capsular wall does not remain in the path of the fragmenting surfaces because the fra~menting surfaces move it away and close the opening leading to the fragmenting zone with gre~t frequency during the rotation while permitting the rougher cr higher mass, more rigid portions of the lens to be fragmented~
Th~ factors useful in surface-discriminatory fragmenting differ from eye to eye or tissue to tissue arld may be selected in accordance with the surgeon's observations. These factors are the speed of the moving surfaces with respect to the tissue, the holding pressure from aspirating vacuum and irrigating liquid, the location and position of the . mo~ring surfaces, the rake angle of the cutting edge of the moving surfaces and the shape of the portions of the moving surfaces most related to ::avitation.
These actors are establishe~ by the surqeon as a ~unc~ion of the ma s of the capsular wall and th~

:` ~

WO~4/211~ ~13 6 3 ~ ~ PCT~S94103~ 1 !

mass of the tissue to be fragmented, the stiffness and smoothness of the capsular wall or other healthy smooth tissue and ~he hardness and flexibility of the tissue.
The moving surfaces of the fragmenting tool hit the S ~ells at a substantially tangential angle and distort them or cut them with their leading edges while the trailing edges create cavitation that further breaks and mixes the tissue without imparting such force to the tissue in a direction that may injure the capsular wall.
For large and rigid or for rough surfaces, the sAear force and cavitation is sufficient ~or fragméntatiQn whereas for more flexible, lower mass and smoother surfaces, the leading edges and the cavitation tend to move the surface away and thus avoid fragmentation. The aspirating port or ports tend to pull the fragmented material internal to the tool~ a As the lens is reduced in mass and freed from its connection to the structure of the eye, its tendency ko mov2 away from the cutting edges is increased. This may be compensated for by~ changing the direction in which th~ cutting edges impact the lens sufficiently often to neutralize the tendency of the impact to move the l~ns in one direction; or (2) causing two clltting ::
SUBSTJTUT~ S~EFT (RllL~ 26) , WO94/211~ 213 6 3 ~ ~ PCT~S94/03~K

edges to neutralize each other by impacting the lens in opposite directions at the same time. In embodiments in I which the direction is changed in a manner that prevents the lens from being caused to move by repeated tangential impacting of the lens by the cutting edges in the same direction. Without such changes in direction, the impact may cause rotation of the lens. The changes in the direction the cutting edges impact the lens may ~ be accomplished by repeatedly reversing the motor with a ¦ 10 reversing switch that changes the polarity of dc power applied to the dc motor from the power source so that a rotating tip changes direction of rotation. Noreover, an automatic reversing switch may be used or the tip may have a substantially linear or a curvalinear reciprocating motion applied to it to cau~e it to move tangentially to the surface of ~he lens in one direction and than in another direction, such as by applying ultrasonic or subultrasonic vibrations to the shaft holding the cutting surfaces.
In a preferred embodiment, a tubular member : has a central aspirating channel along its longitudinal axis with one end having a fragmenting tip and the other end being adapted to rotate th.e tube. The fragmenting tip has at least one slotted fragmenting surface,~lwith the slot extendin~ substantially in a ~ SUB~T3TU~ ~HE~T (RllLE 26) WO 94/~1183 213 6 3 5 ~ PCT~JS94/03446 direc~lon parallel to the longitudinal axis of the tube for at least a shs~rt distance. The sec~ions between slots at the end of the tube may be bent inwardly to provide a blunt top surface or offset to S form a top drill bit. The longitudinal leading edge of the slots are positionPd to establish a ralce angle and the surf aces may be shaped to provide a - f luid pressure inwardly or outwardly to creat~ more or less cavitation so that a tip can ~se selected by the surgeon in accordance with his needs.
To provide the desired cavitation, t~ere is a blunt trailing edge shaped lto increase cavitation.
The leading edge offers less resi~tance to the lens matter ~ and any viscc~s f luid in the eye or lS other f luid through which it moves than khe trail ing edge, the trailing edge b2ing adapted to iracrease c:avitation while the leading edge compresses, distorts and cuts the tissue that is to be removed~
In one embodiment, the blunt end faces slightly outward1y from the circle of revolution j of the tube to create maximum c:avitation outside the shell of the tube: rather:than inside. The leading edge may be at an angle to provide sharpness and the ad j acent t wall may extend outwardly to create inward flow and i:

~.

. WO94/211~ PCT~S94/03~ ~
~136 3~2 --,! .

hold tissue and draw tissue inwardly in cooperation with the aspirating negative pressure.
The diameter of the tube and the number o~
slots ~re sel~cted to provide the selected amount of ca~ritation and cut~ing. The width of the slots is selected to avoid the movem nt of the more flexible tissue that is not to be fragmented in front the leading edge but short enough so that the heavier mass, rougher-surfaced and/or more rigid material to be fraqmented does not move away because of its inertia during the rotating. In one embodiment, the cavitation is at low frequency ~elow the ultrasonic frequency range . In a pref erred embodiment, the tip is rotated in continuously in one dixec~ion or 15 ~ ~ by rotating it first in one direction and then in the opposite direction, reversing between clock~ise ~ and counterclockwise to cancel direction~l :
accel~ration that could be a~plied to the tissue.
: : ~
: In this embodi~ent, in addition ~o the rotation, the time is ultrasonically reciprocated.
1 ~
As can ~e understood from the above -~ ~ descrIption, the technique and ins~rument o~ this ~ ` invention ~have several ; advantages, such as: ( 1) ~ ~:
they ~selectiv~ely fra~ment some tissue without ; 25 ~ damaglng other nearby t1ssue; and (2~ they are able WO94/211~ ~ PCT~S94/034~ ~
( 13~-$

to fragment, mix and aspirate tissue arld ~n the c:ase of cataract removal, also scrub the capsular wall without damagin~

SUMMARY OF THE DRAWINGS
The above noted and other ~eatures of the in~ention will be better understood from he - following de~ailed description when considered with referiPnce to the accompanying drawings, in which:
FIG r l i a simplified elevational view of a handpiece and control console for fragmeinting and removing cataracts in accordance with an em~odiment of the in~ention;
FIG. 2 is an enlarge~ perspective view o~ a ¦ portion o~ thie embodiment of FIG. l;
FIG~ 3 is a fragmentary sectiona1 view of another portion of the embodiment of FIG. l;

F}G. ~ is a fragmentary perspective view of another embodiment of blade poxtion usable as a ! l!; replacement for the blade portion in the embodiment of FIG. li p FIG. S is a pl~an view of the embodiment o~ FIG.

4; ~ P

ff wog4nll~ 13~3~ l PCT~594/03~6 FIG. 6 is a fragm2ntary elevational view, partly sectioned and partly diagramatic of another embodiment of handpiece;
FIG. 7 is a ~ragmen~ary ele~ational vie~ of another embodiment o tool portion;
FIG. 8 is a top view of the embodiment of FIG.
7;
FIG. 9 is an elevational right hand view of ~he embodiment of FIG. 7;

FIG. 10 is a fragmentary elevational view of a tool tip which represents a variation o~ the tool tip o~ FIGS. 7-~;
FIG. 11 is a diagramatic top view o~ a tool tip ~llustrating a first step use*ul in making the embodiment of FIGS. 7-9;
FIG. 12 is a fragmentary elevational Yiew of ~he tool tip shown in ~IG. 11;

FIG. 13 ~s an ~levational view of a tool tip illustrati~g a second step in preparing the 20 ; I embodiment of FIGS- 7-9,o FIG. 1~ is a top view of the tool tip shown in q ~: ` FIG. 13; ~
IQ
~ FIG. 15 is a ~ragmentary perspective view !~
:~ illustrating an additional step in preparing the embodiment o~ FIG5. 7-9;

~ WOg4/~11~ 213 6 ~ 5 2 PCT~S94/03~

;~ FIG. 16 is a perspective view illustrating still `, `another possible step in preparing a tool tip similar to the embodiment of FIGS~ 7 9;
FIG~ 17 is a block diagram of a process for using `~ 5 the instrument of FIGS. 1 through 6 to remove a cataract;
FIG. 18 is a simplified cross-sectional view of an eye and cataract xemoval handpiece tip illustrating a ~, portion of the technique of this invention;
FIG. 19 is a fragmentary elevational view, partly sectioned and partly diayramatic of still another embodiment of handpiece;
FIG. 20 is a sectional view of another embodiment of handpiece, and FIG. ~1 is a sectional view of a tip usable in the embodiment of FIG. 20.

DETAILED DESCRIPTION
In FI&. 1, there is shown an elevational view of a surface-discriminating fragmenting handpie~e 10, ., connecting tubing 23 and a console 21. The handpiece 10 includes a drive portion 11 and a 3 ; surface-discriminating fragmenting tool having a : ` blade portion 14 and a tu~ular sleeve portion 12.
. ~
: ~
~ ` 17 ~.

SUBSTITUT~ S~EET (R~L~ 26) WO94/211~ PCT~S941034~
3 5 2 ` ~ ~ i The tubular sleeve portion 12 includes a tubular casing 13, and an inner tabular asp~rating drive shaft or sleeve 18. The drive portion 11 houses tha motor, an on-off switch 20 and connectors for irrigating ~luld and aspirating vacuum pressure.
The blade portion 14 includes blades 17A and 17B each of which ~is ~astened to the rotatable ~ tubular shaft 18 at diametrically opposite loca~ions on t~e shaft and each of which has a correspon~ing one of the blunt tips 15A and 15B turned inwardly to avoid cutting. The outer sleev~ 13 includes within it a movable sleeve l9A so that upon longitudinal movement cf the button l9 with respect to the outer casing~13 of the tubula~ sleeve pcrtion 12, the 15 ~ blades 17A~ and 17B m~Ye apart in a fragmenting position in~response to one direction of movement of the shaft~ 19A and are forced within ~the; movable ; sleeve l9A within the tubular sleeve 12 against thé~
pressure~of~the~ spring~like blades upon~movement~ in~
~; I the other~ldire~ction to fit~within~a !sma}ler ,incifi;ion such as a~2~millimeter opening. Th~ blades 17A and 17B a~e narrower in~the~direc~tion of rotation and ~-.
blunt cn~the~traili~ng edge to cause cavitation.
With~ th;is~arrangement, the blades 17~A and 17B

5~ may be~mo~ed tog~ether~for insertion of the handpiece WC) ~4/21183 213 6 ~ 5 2 PCT/US94/03446 10 into the c:apsular sack through a relati~rely s~nall aperture and then permitted to expand outwardly so that the upon rotatio~ of the blade portion 14 of the tool sectic)n ~he cortex and nu ~ us are f ragmented within th~ capsular ~ack . In the embodiment o~ FI~. 1, the handpiece lo includes a motor for rotating the shaft and a tubular connector 23 for aspirating fragments. The console 21 may include for cooperation with the handpiece 1o, standard source of electrical power, a vacuum source, a source of irrigating l iquid and a pump f or irri~ating liquid. Thesè elements are conventional and are nc~t part of the invention except insof ar as they cooperate with the haP~dpiece 10.
In FIG. 2, there is shown an enlarged fragmentary perspective view of the blade portion 14 of the tool assembly having f irst and second blades 17A and 17B with corresponding blunt ends ~ 5A and lSB O The blades 17A and 17B are suf f iciently I f lexible in the embodiment of FIG . 2 to expànd until they f orm outwardly c:urved cutting surf aces extending beyond the surfaces o~ sha~t 13 ~FIG. 1) and have sharpened edges 32 and 34 tangentially to or pointing inwardly from the circles of rotation f ormad as they rotatQ . ~hen the blades 17A ar~d 17B

I

WO94/~ll~ 2 1 3 ~ 3 ~ ~ PLT~59J/03~K

are pulled inwardly by movement of the sleeve l9A
¦ upwardly, ~hey ~it within a cylinder having a diameter of less t~an 2 millimeters.
While the embodiment of FIGS. 1 and ~ havQ
blades with sharpened edges pointing tangentially to or inwardly from the direction o~ rotation, sharpened edges are not necessary and th2 angle of ~ attack or rake angle of the sharpened edges when they are part of an embodiment may vary. iHowever, 1~ ~he angle of attack may be tangential to the path of rotation or any angle on either side. For this ~ .
purpose, any one of several multiple blade ;' assemblies 12 with their attached inner drive shaft 18 may be inserted into t~e sl~eve portion 12 and drive portion 11. The blade portion is selected by the physician and one fact in such selection is the angle of attack of the blades.
To permi~ compressing of the blades ~7A and ~ 7B
~ , into a protective sleeve, the tubular s~eeYe por ion ; 20 !~ 12 ~incluq~s three coaxial~sleeves 18, l9Aj andl 13 tFIG. l) ~in that order outwardly from the central , ~
; axis. :~The~blades are mounted to tubular drive sleeve 18 for: rotation~ therewith and there is a sp~ce:between~slee~es: 18 ~and l9A for irrigating ~ 2~5 ~ fluid~:to flow. :The sleeve 13A is affixed to the `'``~ : 20 ~J

WD94/~tl83 2 1 3 ~ 3 5 :~ PCl ~594/03~K I ~

button l9 (FIG. 1) and moveable axially with r~spect to sleeve 13 to engage the blades 17A and 17B and compress them inwardly.
~n ~I~. 3, ~hera is shown a fragmentary longitudinal sectional view of the sleeve portion 12 and drive portion 11: ~1) having within the sleeve portion 12 the rotatable tubular aspirating àrive shaft 18, the tubular protective sleeve l9A and the outer sleeve 13; and (2) having within the drive portion 11, a motor 40 for rotating the aspiratinq drive shaft 18 to turn the blades 17A and 17B, (FIt:;.
1 ) a hollow aspirating tube 27 to apply vacuum pressu~e to the interior of the shaft 18, an irrigatin~ tube 17 collununi~ating with the tube l9A
to apply irrigating f luid through the tube l9A and electrical wires 25 to control the motor 40. The shaft 18 i5 coupled at one end 42 tc: the output shaft of 44 o~ the motor 4~ for rotation therewi~h and to the tubular connection 45 for aspiration.
As shown in this vi~w, the outer wall 13 supports within it a movable wall l9A with a button extending through a slot ~ in the ouker wall 13 by which the wall l9~A may be moved upwardly and downwardly to bend the hlades 17A and 17B inwardly for retraction or permit them to expand outwardly in .

~ ' ~l W094/211~ ~136~ PC1~5~4/03~

', the cutting position to their normal position f`or rotating and in some embodiments still further under centifugal force when rotating. However, the moment of inertia of the blades is su~ficient so that the centrifugal force does not force ~he points to point outwardly and only th~ bent flat surface iB
presented to the outer wall during rotation. It is ~ spaced from ~he movable tube lgA to permit ~rrigating fluid to flow therebetween and contains in its center the opening lS which extends downwardly for aspiration of tissues.
To provide irrigating f luids, the conduit 17 is ; connected throug~ the cable 2 3 to the console 21 (FIG. l) from which irr~ating liquid is pumped through the conduit 17 around the motor 4 o and to : the space between the movable tube 19 and shaft 18 to supply irrigating f Iuid to the capsular sack . To aspirate tissue, the central opening ~5 in 'che sha f t . 18 passes through an opening 29 in the wall of the , 1, 20 I shaft 18 and communicates through the~ sealed circular ring 31 with the aspirating conduit 25.
. , , , ~
The conduit 25 passes around the motor 40 and i~
~ through the cable 2~ to the console 21 which applies ;~ sl~ght negative pressure to aspirate tissue~ The 25 : cable 23 als~ carrieq ~letri~l conductors ~or the ~;

~,.;
1:

wog4e~ 6~2 PCT~594/03~K

motor 40 which are co~nected in series between the switch 20, and a source of electrical power in the console 21 and the motor 40.
To use the embodiment of FIGS. 1-3, an incision is made for the insertion of the surface-discriminating fragmen~ing handpiece lO. The surface-discriminating fragmenting handpiece 10 fragments and:permits aspiration of ~he tissue but avoids damaging nearby smooth, flexibl'e walls.
Instead it fragments rougher, more rigid surfaces of higher masses. This -eurface discrimination is co~trolled by the moving surface of the blades 17A
and 1~8 which permit the diseased tissue to be strained or cut by the bla~es and f~rther fragmented by the forces of cavitation within their fragmenting zone but which move at a rate of speed and have openings between them of:such a size that the more integrated, lower mass or more flexible and smoother tIssue does not f~ll within their fragmenting zone ,l 20 l l but ,is ~moved away the moving su~faces. The aspirating ~pressure, ca~itation and turbulence is !?
counteracted or attenuated within the sphere of ~he rotati~g~ring to avoid damage to the ~lat surface !7 tissue. : :
.

~ 23 ;:
. , , WO94/~1183 PCT~S94103~
2 1 3 ~ 3 ~i 2 ! '` '- ~

In the case of cataract removal surgery, a small incision of ~ to 7 millimeteirs and preferably 3 millimeters in the ~chlera along the corneal border at 12 o~clock and another incisio~ of similar dimensions in the capsular wall. The instrument i5 inserted and fragments the higher mass, more rigid, rougher lens without fragmenting the capsular wall.
The actual time that the fragmenting zone must be open to fragment diseased tissue without injuring smooth walls differs from eye to eye or tissue to tissue and may be selected in accordance with the s~rgeon~s observations prior ~o use . It is a function Of: tl) the rigidity of ~he tissue; (2) the mass of the tissue; (3) the angle of the tissue to the direction of movement .of the tool; ( 4 ) the ro~ghness of the surface; and ( 53 the effect of the negative pressure pulling the tissue inwardly such as the aspiration vacuum pressure which may ~ary in i~s effect depending on the size and shape of the tissue.
i~ D
The surface discrimination of the tool is controlled by moYing surfaces which cause the diseased tissue to fragment under impact, referred to as phacotmesis, and cavitation forces, referred to as phacocoelosis, ~ut which move at a rate of WO94/21183 2 ~ 3 6 3 5 2 PCT~S94103~

speed slow enough o that the more integ~ated, more ~lexible, lower mass and smoother tissue is moved ~ away withou~ fragmenting. The surfaces of the j instrument fragment tissue that~ is stiff; ~2) ; 5 has a high mass and large inertia; and t3) is at an angle to the cutting edge close to 9O deyreeis.
`To take advantage of the differences between the tissue to be ~ragmented and the lower, more flexible tissue, the surgeon removing a cataract adjusts the speed of movement of the tool surfaces, the aspirating and irrigation rates, the rake angle of the leading edge of the blade surfaces and the ca~itation level as cont.rolled by position o~ blade surfaces, the velocity and ~he shape o~ the moving lS surface, especially the trailing edge of the blades.
The adjustment is made to ~ragment the c~rtex because of its higher mass, modulus of e~asticity and projectio~s in the path of the tool surfaces but :
to move the capsular wall away from the biades because of its lower mass, lower modulus and fewer projections closer to 9O degrees. Tips are replàced to cha~ge ~he ra~e angle and~cavitation sur~aces~
~:!
~: The aspiration pressure is more effective within the mo~ing surfaces of the rotating tip. I~
i~ low enough to pull the fragmented tissue and 3 ~ :

;1~ .
., WO94/211~ ;:~ PCT~S~4/034~
~i3~352 ~^ , tissue to be fragmented but does not hold the smooth wall against movement nor pull it inwardly. The rotating surfaces move the smooth wall outwardly and provide some counter pressure to the aspirating pressure inside the fragmenting zone. In one embodiment, radially inwardly extending edges ~urther pu1l and mix tissue within the ~ragmenting zone.
To better describe this and other embodiments, some special terminology is useful. For purposes of this description, the words, "low power" means less than one horsep~wer (1. 341 kilowatts) . In this description, the words, "motion resistance" means the resistance of a portion of tissue to movem~nt when impacted by a moving tool surf ace caused by the inertia o~ the tissue and t~e effect of the inertia of other :tissue connected to it taking into : consideration the flexibility of the connecting tissu~.
In this description, the words, "fragmenting velocity", means the minimum velocity of a moving surface of a tool with respect to predetermined stationary tissue that~the moving surface of the tool impact~s which fragmenting velocity is suf~icient to caus~ strain in the tissue of at least ~:` 26 WO 94/21183 2 :13 6 3 5 2 PC:T/US94/03446 r . I ~

ten percent of the distance moved by the entire tissue mass and to break the tissue by combine~
strain, cutting and cavitation effects when~ he i predetermined stationary tissue has a predetermined motion resistance; a~d ~2) the tool surface has ! sU~ficient kinetic ene~gy ~o mai~tain its ~elocity constant in spite of the impact. The fragmenting velocity is affected by: (1) the angle the motion of the moving surface makes with the surface of the I lO ~ tissue; and (2) the momentum of the moving surface.
. In the embodiments of FIGS. 1-3, a ring or partial ring having a diameter of 2 millimete~s in the widest distance perpendicular to the axis of revolution ~orms a surface of revolution when ~ .
rotated having at any one time open spaces and a solid cutting ring. The xing is rotated at approximately 120,000 rpm ~revolutions per minute).
Th~ solid ring is approximately 0.50 millimeter wide along the surface of reYolutionf leaving an open . area in the surface of slightly less than 9 square mill~meters and more precisely 8.9 square millimeters with a length of 2~4 millimeters at the longest circle of a segment.
The time between portions of the solid ring 1 25 sweeping across any surface of revolution is ~; ~ , '' ~ W094/211~ PCT~S94/03~ ~.
213~3~

approximately every 250 microseconds and should be no longer than once every 3 milliseconds (1,000 rpm) but may be as short as 0.75 microsecond (400,000 rpm). ~ith this arrangement and with parameters adjus~able for the particular circumstance, the capsular wall does not enter into the fra~menting zone within and near the surface of revolution and ¦ is no~ cut and yet the ~ing is able to fragment ~he lens ~or easy aspiration.
In FIG. 4, there is shown a second embodiment of blade portion 14A having a shaft 18A connected to a blade 17C formed as a partial zone of a circle or an arc extending f rom the sha f t 18A and having a pear-shaped, blade portion with: (1) blunt trailing edges 20; (2) sharpened inner edges 22; (3) a wide base attached to the shaft and narrower alon~ t~e axis of the tube 18A so that there is at the wlde portion a blunt trailing edge and a sharpened leading edge as the cutting blade rotates about the shaft 18A; and (4) an axis of rotation along the shaft 18A betweeA the basa and the narrower upper portion. : The apex is generally blunt, but in some : embodiments has a ~rill shape at the apex 24.
~ It has been found that the sharpened edges i 25 strain and elongate the c211s of higher mass rigid ~094/211~ 213 fi 3 ~ 2 PCT~S94/03*~ ¦

material but push away flexible and low mass material. The leading edges under some circumstances cut or scrape fine particles from the ha~der material that might otherwi~e pl~g th~
aspirating channel but the caYitation effect fragments the particles into small particles that can easily be aspirated~ The blades are shaped to maximize cavitation that liquifies and stresses lens matter and any viscous f luids and c:auses ~ragmentation and mixing of the higher-mass more rigid material. In the embodiment of FIG. 4, the blades have two ~lunt sides and a top blun~ portion 24 and at the mounting base to the tube 18A for strength at the bottom and to form a non cu~ting . surface at the top~ ¦
In FIG. 5, there is shown a top view of the embodiment of FIG. 4, having a portion 14A with a blade 2OB shaped with a thicker portion having a blunting surface 24 at its upper end facing away from ~he direct1on o~ the tubular shaft 18A and !~rl~3 , ! rotating thereabout. However, in some emblodiments it has a cutting edge to permit it to provide an : abrading center area in the forward direction for ~: positioning at a point to be fragmented. This embodiment operates~ substantially the same as the , :
:

~ WO 941111B3 ,~ ~ ~ $ ~ ~ ~ PCT~S94/03~

"~

.

prior embodim2nts except that its unique shape enables careful placement for special purpose~.
Instead of a cutting edge, the top portion 24 may ~e bent inwardly or may be blunt to a~oid cutting at its top~
In FIG r 6, there is shown a fragmentary, partly diagramatic and partly longitudinally sectioned view o~ another embodiment of hand tool lU~ which is operated by a simil~r dental drill motor 40 and adapted to receive a tool by haviny insert~d therein the aspirating tube 18B of the sleeve portion 12C
substantially identi~ally to that of the embo~iments of FIGS. l~S except that the blade portion is constructed in a dif~erent manner on the end ~f the shaft 18 as will be described hereinafter.
The hand piece lOA includes in addition to t~e aforementioned motor 40, an aspirating drive sleeve 18B, an outer housing 60 and a motor~tool sleeve coupling 62 wi~h: (1) the motor 40 being connected to the tool sleeve 18B through the coupling 62 and ; i being located within the `housing 60; (2) with the , : sleeve 18B extending outwardly thereof for rotation by the motor ~0 through the coupling 62 during opera~ion of the hand piece.

~: 3 0 ."

.1 WO94/211~ 213 6 3 ~ 2 PCT~S94103~ l To enclose and provide the necessary liquid and vacuum connections to the operative tool, the housinq 60 includes a motor housing portion 70 and a tool and coupling housing portion 72 intergrally ~ormed together with tubular connectors 74 for irrigating fluid, tubular connector 76 for aspirating negative pressure and hole 78 for air venting being pr~vided through:the housing ~0. The air vent port 78 is an opening extending into and communicating with the interior o~ the motor housing portion 70 to provide cooling to the motor 40. The irrigating fluid connector is ~n openîng : communicating with the interior of the housing portion 72 to apply fluid therethrough ~or eventual passage through the protective cleeve 13~ on the outside of the tooling slee~e 18B and to the operating point in a manner to be described more fully hereinafter.
The aspirating ~onnecting opening 76 is dapted ~0 to receive tubing for applying negative pressure through the motor-tool coupling 62 to the lnterlor of the tooling shaft 18B to withdraw:material during use of :the ~h~and piec~. :The ;~orward end of the housing portion 72 includes external threads 8~
2~ ~ whLcn enqage: intern-l teeth on the prQtective sleeve WO 94/21183 . PCTtUS~4/03446 ~3~3~2 13A and a shoulder with an 0-ring 80 positior.ed in it so that, the protective sleevc 13A can be threaded onto the housing 60 to enclose a portion of it sealingly and ext~nd through ~ ts outer end ~n a manner to be described hereinafter.
To connect the motor 40 to the sleeve portion 12B, the motor-too} sleeve coupling 62 includes the motor output shaft 90, a cylindril-al boss 92, a cylindrical suppoxt member 94, an annular groove 96 within the boss 92, two counter bores 98 through t~ae boss 92 at the bottom of the annular groo~re 9 6, an opening 100 communicating with the aspirating c::onnector 96 and extending through the cylindrical s~lpport 94, a cylindrical opening 95 sized to 1~ receive the sleeve 18B and a brazed connection 102 more firmly fastening the boss 92 to the sleeve 18B.
The support 100 receives the motor shaft 9o and the boss 9 2 which ro~ate within it and are supported by it. The groove 96 communicates with the opening 100 as it rotates because of its annular shape and receives vacuum pressure which it transmits through the openings 98 into the sleeve 18B to create negative pressure in the wor3~ing tip through this elongated sleeve.

:: :

~ W094/2l183 ~13 ~ 3 a 2 PCT~3594/03~K

.

With this arrangement, the sleeYe 18B i8 rotated and carries vacuum presisure with it to the tip. The brazed connection 102 aids in trans~itting force from the output shaft 90 to the shaft 18B
th~ough the boss 92 by increasing the firmness of the connection between the tool sleeve 18B and the sha t 8 O .
- To mount ~nd support the tool sleeve 18B, the . protecti~re sleeve 13A in the embodiment of FIG. 6 irlcludes a cylindrical base member 110 ha~ring internal teeth 112 adapted to ~ngage the internal teeth 82 of the housing 72 and is sealed against the flow of~ fluid therethrough by the o-rings 80 compressed between the en~arged cylinder 110 and the housing portion 72. A narrower outer sheath portion ~:~ 114 is inter~rally formed with the cylindr:ical portion llO and receives a:cylindrical passageway~
` : :: :
~ormed~ between the inner tool sleeve 18B and its outer: tubu:lar sur~ace to ~permit the flow of :
,l irrigating:liquid between the outer protectiYe Fleee 13A and the i~ner member tool sleeve 18B into the :
: ` : : `
: capsular bag.:
ith this arrangement, the tool sleeve~l8s can be~rotated ~y;the motor 40:and~at the same time: (1) 25~ irrigating ~fluid can: be applied between it and the W094/211~ PCT~S94/03~ l 21~63.S2 protective outer sleeve 13A; and ~2) aspirating 1:
negative pressure can be applied to pull fragments along its longitudinal axis. At its outer end, the fragmenting tip or blades are ~ormed in a manner to be described hereinafter.
In FIG. 7, there is shown a front elevational view of one embodiment of a tool having a sleeve portion 12A and a blade portion 14B with two blade members formed in its outer end and separated by an opening 120 longitudinally passing along the longitudinal axis of the tool to form blade portion 14B at the end of the same cylinder for~ing the sleeve 12A. Both the blade portion 14A and sleeve portion 12A are forme~ on a single integrally formed cylinder that serves as the aspirating drive shaft 18B. Aspirating holes extend throu~h the tip of the blade portion 14A orthogonal to the longi~udinal axis and the slot 120. To receiYe som~ material or aspirating, the aperatures 122 and 123 are approximately 0. 04 inch from the tip 24 of ~he blade ~i.
.
portion 14A and the diameter of the tu~e 18B is approximately o.042 inch. The diameter of the aspirating holes 122 and 123 is 0.018 inch and should not be larger than 7 millimeters.

34 p WO 94/21153 213 6 3 ~ 2 PCTIUS94103446 i FIGS. 8 and 9 are a plan viaw and a right elevational view of the embodiment of FIG. 7, respectively, showing the sl ot 120 having a width o~
0. 008 inch and extending downwardly approximately 0~ 07 inch. As best shown in FIG. 8, the edg2s of ` the walls of tube or sleeve 18B along the slot have a larger or blunter trailing edge shown at 126 and.a sharper leading edge at 124 in one embodiment as well as a blunter edge at 13 0 and a sharper edge at 128 so that the sharper edges as the item rot tes counter-clockwise as shown in FIG. 8 elongate or cut the tissue within the eye and create cavitation at the blu~ter edge.
:~
In FIG~ I0, ~here is i~own a fragInentary front : : ~
elevational vlew of another embodiment showing the : , .
tip along the slot ~rought together~ welded and .offset ~o provide a sharper and a blunter edge by ~: ~ offsetting thel edges along the slot to a greater : :
~ degree but without the need for changing the thickness of the tube walls. This embodiment forms a r~ke angle of ~0 de~rees and two cutting edges but slots at three locations in lthie wall of sleeve 18B
can also be f ormed ~instead of two slots 180 degre s apart~ provlding a ~60 ~degree:rakè~ angle and thre~ :
~ 25~ :cueeinq;~edges~ or four;il:ots to provide a 45 degree `~ 5 ~ :
~," ~ ' WO94/21183 . PCT~S94/03~
` 213~3S~, ~

i rake angle and four cutting edges. Moreover, the tips can be brought togather as in FIG. lO to ~orm a smooth protective dome or can include a cutting edge or be open. the tip can also be twisted, which will , 5 change the rake angle along the slot and provide a ¦ cyclone fan pulling effect.
To form the e~bodiments of FIGS. 7-lO, a - tubular sleeve is slotted at ~20 as shown best in FI~5. ll and 12 and pinched together. The two sides . lO are then offset in space laterally in a direction along a plane passing through the center of the slots and the longitudinal axis of the sleeve as shown in FIGS. 13 and 14 and the tips pinched together and brazed together to form a tip such as that shown in FIG. lO. Prior to closing the tips 140, the narrower and blunter edges may be further . . shaped by cutting one wall at a more acute angle than the other wall and then removing the other sides of the slot with a re~erse cut so as to form flat cuts and sharpened cuts.
To form other rakiny angles and shape the blade to p~ll viscous fluid or such viscous fluid, ~he ends are offset, twisted and brazed as shown in FIG.
l5 and 16, first offset along a line or plane aligned with the two slots and longitudinal axis and :

:

~1363~;2 W094t211~ P~T~S94103 then twisted at a slightly di~ferent angle to form a di~ferent rake angl~ and cyclone pu~p effect. The tip is normally smooth at the very tip 140 but has a cuttlng effe~t as it moves radially outwardly.
In one version of the preferred embodiment, the tube has an outer diameter of 42 thousandths (0.042) inch with two diametrically opposed slots. The ends are moved together in a curvature leaving a slot about 8 thousandths inch wide at its widest point and extend from the top approximately 70 thousandths inch (70 thousandths long). Ninety degrees remo~ed from the two slots are central a~pirating apertur~s having a diameter of 18 thousandths of an inch and being circular in cross section. They are located ~ , with their bottom edge generall~ adjacent to the end of the s~ots. ', The tube usually rotates at approximately 1600 ' hertz when fra~menting the nucleus in a preferreid ~!~
~ ' embodiment having tw~ cutting edges and the wedged surfaces of the slots have one edge that is in a range of l thousandths of an inch to twenty th~usandths of an inch thick and a trailing edge that is in the range o~ ten thousandths of an inch i~
to fifty thousandths of an inch thic~. Preferably, :;~ 25 it should be in the range of 300 hertz to 4000 hertz K

:: :: : 37 ii .
?'~

wos4/211~ 2 1 3 6 3 ~ 2 PCT~S94103~ ' ! but may be slower or faster when at a location in ~he capsular sac not near tissue to be preserved or which may be moved to change other tissue. The I slots and rate of rotation are selected to provide, ¦ S in the preferred embodiment, a surface moving ~00 ¦ centimeters a se~ond at the fastest point on the ¦ curved moving surfaces and preferably to provide a surface mo~ing at the ~astest point within a range of s meters a second to 40 centimeters per second at ~0 the fastest point but may move slower or faster under some circumstances.
Since it is a rotating surface which curves inwardly ~oward the center, the speed is Yery 1QW at the center and under some circumstances does little lS fragmenting at the center and more and ~ore fragmenting as the rotating radius increases to the sleeve radius. The slot is next to tissue for a very s~ort time such as between 10 milliseconds and l millisecond. Each cutti~g edge sweeps past a point about once every 625 microseconds, pre~erablyO
I , I or in ~he normal range of once every 3 milliseconds ¦: to once every 400 microseconds.
In addition to zones of a sphere and sections :
of a cylinder intended for use within an eye, other shapes ~of moving surfaces may ~e used and the tool 'i '.
1~

!

~136352 WO94/211~ pcT~ss4lo3~K

has uses other than ~or cataract removal such as in vascular operations. For example, multiple zones of a sphere may b~ spaced ~rom eaich other at a shorter dis~ance so that the ~tem need not be rotated as fast and motion other than rotational motion may be used to prevent entrance of the tissue into the fragmenting zone. A convenient embodiment for removing structures around veins or arteries during vascu}ar operations is dumbell shaped so that a recess fits around the vein while spherical cutting zones are posltioned on either side of the vein.
In some embodiments, the moving surface is formed of a curved member attached to a rotatable 7A
sha~t having a sharpened edge at an angle o~ betwee~
0 and 60 degrees but preferably 45 degrees with a surface of revolution which sur~ace ~a~ a center of rotation aligned with the rotating shaft. ~he sharpened edgei of the curved member may facei away from the center of rotation so that ~he cutting ` action of the shaxpened surface is into the cortex and core material of a cataract.
In FIG. `l7, there is shown a blook diagram generally illustrating the steps in a cataract extrac:tion and lens implantation technique 50 comprising: ~1) the step 52 which includes the :~ : a .
~: 3g :

WO9~121183 PCT~S94/03~_ ~ 1 3 5 3 ~ 2 preliminary ~ubsteps of maintaining the anterior chamber and ~aking the incision into the capsular wall; (2) the step 54 of fragmenting and removing the lens; and (3~ ~he step 56 which includes tha substeps necessary for implanting the lens.
In performing this technique, the step 52 which includes the substeps required to make the incision and maintain the ant~rior chamber and the step 56, which ~ncludes the substeps necessary for implanting are not by themselves new and many of the steps are described in Anis, Aziz Y., "Illustrated Step-by-Step Description of the Anis Dry Extra Capsular Cataract Ex~raction Technique With ~n-the-Bag ~ens Implementation", Seminars ln OPthalmoloqy, v. l, N.
2 ~une), 1986, pp~ ll3-l29. Moreover, the removal o~ the lens may not be ~ollowed by implantation but may be part of a treakment in which the aphakia is treated by contact lens or glasses~
The step 54 of fragmenting and remo~ing the lens in~ludes: ~l) the step of inserting the handpi~ce; (2) the step o~ extending the b}ades in some embodiments within the capsular bag; and (3~ .
the step Q~ breaking and removing the hardened part !7 of the~ nucleus. These steps are all performed through a small incision while tha anterior chamber : ~ 40 ~;~0~4/21183 .~1 3 ~ 3 ~ 2 PCT~S94/03~

,....................................... .

is maintained with a viscoelastic medium.
Hydrodelinea~ion may be performed as described in United States patent ~,908,015, if desired, but such hydrodelineation is not part of this invention.
The step 52 which includes preliminary substep~
. ~ maintaining the anterior chamber and making the incision in the capsulax bag includes the substep of makiny a small incision in the capsular bag, preferably no greater than 3 millimeters in length an~ in the range of 1 to 2 millimeters. This incision is made while the anterior chamber is maintain~d and is made as small as possible to maintain the structure of the capsular bag to the extent possible. Through this small incisiont the step 54 of frasmenting and removing the lens and the step 56 of implanting a ~ens are performed~ Under some circumstances, the incision may be 4 or 5 millimeters b~t should always be less than 7 millimeters.
With the posterior capsule in ~ocus in the focal plane of the microscope, the handpiece 10 is introduced through an incision shown at 220 in FIG.
13 in the wall of the capsulary sac. The tip of a handpiece 10 is thrust through the incision in the wall of the capsular bag and into the lens therein.

~: ~ 41 WO94/211~ ]PCT~S~4/03~ , 21~63~2 The bla~es are xapidly ro~ated while slight negatîve pressure is applied to aspirate the fragments. The rotatin~ blades are inserted gradually into the cortex and nucleus and from time to time a small amount of irrigating fluid is injected. Fragmente~ cortex or n~cleus material is aspirated. After removal o~ the cataract and the handpiece with the capsular sac relatively intact, a -lens implant is inserted through a relatively small opening as described in the above publication of Anis~
Generally, the nucleus is first removed then the cortex. The surface - disc:rimin~ting f ragmenting handpi~c~ ~ragments and permits aspiration of the ::otex and nucleus without damagirlg nearby smooth walls o~ the capsular sac. It avoids fragm~nting the smooth walls with its cutting edges but fxagments ro~qher, sti~fer higher mass tissue, moving it into a negative pressure zone f or aspiration . The smooth more f lexible, lower mass surfaces are moved by the blades which hit it at an angle. The tissue being fragmented is hit at an ; angle and subject to cavitation rapidly and repeatedly with a force each time that does not move the entire material to ~he extent that it may damage :
~ 4~

~094/211~ 2 1 3 G ~ ~ 2 PCT~S94/03~

the capsular w~ll or other healthy tissue that is not to be fragmented but does fragment the cortex.
The surface discrimination of ~he instrument is controlled by moving surfaces which permit the diseased higher mass tissue to be fragment~d but which move at a rate of speed and have openings between them of such a size that the more integrated flexible, lower mass and smoother tissue does not fall within their fragmenting zone. The tissue is not constrained by opposed shear forces of the instrument but are free to move and the cutting edge of the instrument cuts tissue that: (1) is stiffer and has a higher modulus of rigidity; and (2) is at an angle to the cutting edye closer to so degrees and receives less force moving it away.
Thus, the surgeon removing a cataract adjusts the speed of movement of the cutting edge to cut cortex with a higher mass and modulus and more projections in the path of the cutting surface and no~
the capsular wall with a lower modulus and mass and fewer projections closer to 90 degrees so it is more readily moved away from the cutting edge. The aspirating; ipressure is low enough ~o pull i the fra~mented tissue but not the smooth wall. The rotating surfaces move the smooth wall outwardly and : ` :
~ 43 SUBSTlTlJTE SHEFT (R~L~ 26) W094/211~ ~13 6 3 5 2 PCT~594/03~ 1, . .
provide some co~nter pressure to the aspirating pressure inside the cutting zone~
In using this instrument, as the lens is reduced in mass and freed from its connection to the structure of the eye by fragmentation, its tendency to move away from the cutting edges is increased. One way of compensating for this effect may be by changing the direction in which the cutting edges impact the lens sufficiently often to neutralize the tendency of the impact to move -the lens in one direction. The direction is changed in a manner that prevents the lens from being caused to move by repeated tangential impacting of the lens with the cutting edges in the same direction. Without direction changes, such impacting may cause ~he lens to move, such a~ by causing rotation o~ the lens~ Another way is by impacting the lens simu~taneously in opposite directions.
The changes in the direction from which the : cutting edges impact the lens may be accomplished by ~ the repeatedly reversing the motor with a manual reversi~g switch that changes the polarity of dc power ~applied to the d motor ~rom the power source so that a rotating tip changes ~irection of rotation. Moreover, an automatic reversing switch , -'3 '' SUBSTITUTE SHE~ (RULE 26 .!

W094/211~ .~1 3 ~ 3 5 2 PCT~S94/03~

may be used or the tip may have a substantially linear reciproca~ing motion back and forth or a curvalinear reciprocating motion applied to it to ca~se it to move tangentially to the surface of the lens in one direction and then in another direction, such as ~y applying ultrasonic or subultrasonic vibrations to the shaft holding the cutting surfaces.
In FIG. 19, there is shown a ~ragmentary, partly diagramatic and partly longitudinally sectioned view of still anoth~r embodiment of hand tool lOB especially useful after the lens has been reduced in size. Instead of being operated by a dental drill motor 40, it is driven by a vibrator 4OA, which may be any conventional type of vibrator such as those used to operate the tip in the a~ove-mentioned U.S. patents 3,589j363 to Anton Banko, et al., 3,902,495 to Ste~en N. Weiss, 3,693,61 to Charles Kelman, et al, and 4,041,947 to Steven N.
Weiss, et al. Except for the drive mechanism, the handpiece is identical to the embodiment of FIG. 6 and the reference numbers for identicaI parts r~.main the same.
The handpiece lOB includes, in~ addition to the aformentioned vibrator 40A, an aspirating drive sleeve l~B, an outer housing 60 and a motor-tool : 45 ~SUBSTITUTE SHEET (R~ILE 26) ~ W094/211~ . ~ PCT~S94/034~ i 3 ~ 2 ~ " C`
..
.
sleeve coupling 62 with: tl) the vibrator 40A being connected to the tool sleeve 18B through the coupling 62 and being located within the housing 60; ~2) with the sl~eve ~8B extending outwardly thereof for vibrating curvalinear motion by the vibrator 4OA through the coupling 62 during operation o~ the handpiece.
The vibrator 40A includes a conventional oscillator 130, source of dc power 132, and piezoelectric or electromagnetic vibrator 134 electrically connected in ^ lO series with the switch 20 ~FIG.l) to be energized and vibrate the cutting adges (not show~ in FIG. l9) connected to the shaft 12C as explained in connection with the embodiment of FIG.6. The shaft 90A is mounted for rotation in bearin~s 138 and includes a welded arm extending orthogonally and radially therefrom, biased into contact with or fastened t~ a movable portion of the vibrator 134 sa that vibration of.the vibrator imparts rotating motion to tha shaft 90A.
To connect the vibrator 40A to the sleeve portion 12C, the motor-tool sleeve coupling 62 includes the vibrator output shaft 90A, a cylindrical boss 92, a cylindrical support member l , ~

, 94, an annular groove 96 within the boss 92, two ~ ~ I

~ 46 ~ ` SUBSTITlJTE ~EET (RIJL~ 26~
: ~ :

. .WO94/211~ ~ 1~ 6 3 5 ~ PCT~S94/03~ 1 . . . "~

counterbores 98 through ~he boss 92 at the bottom of the , annular groove 96, an opening 100 communicating with the ¦ aspirating connector 96 and .extending through the cylindrical support 94, a cylindrical opening 95 sized to receive the slee~e 18B and a brazed connection 102 more firmly fastening the boss 92 to the sleeve 18B.
The support 100 receives the ~ibrator shaft 90 and j the boss 92 which rotationally vibrate within it ànd are supported by it. The groove 96 communicates with the opening 100 as it moves because of its annular shape and receives vacuum pressure which it transmits through the I openings 98 into the sleeve 18B to create negati~e ¦ pressure in the working tip through this elongated sleeve.
¦ 15 With this arrangement, closing the switch ~0 ¦ (FIG. 1) connects power from ~he power supply 132 ~ to the oscillator 130. The vibrator 134 then ¦ ~ibrates at the frequency to which the oscillator 130 has been tuned by the surgeon being energized through conductors 139~ The vibrator 134 reciprocates the lever 136 turning the shaft 188 repeatedly in alternating directions. This causes the lens to be impacted with the cutting edges, .first in one direction tangential to the lens surface and then ' : : 47 SU~T~UT~ SHE~T (RULE 26) ~r W094/211~ PCT~S941034~
~13S3~2 rapidly in the other, at an angle and speed that avoids damage to the capsular wall, if it should be near, but fragments the lens.
Because the motion is in the clockwise direction and then the counterclockwise direction, the lens is no~
caused to spin because the two impacts are sufficiently close in time with respect to the inertia of the lens to can~el without substantial additive acceleration of the lens in one direction from the impacts. Generally, the frequency is ultrasonic or subsonic but may be selected by the surgeon to accommodate the portion of the lens that is being fragmented by tuning the oscillator 130.
To impact the lens in opposite directions simultaneously, two side by side sets of cutting edges may be rotated in opposite directions or one set of cutting edges may be rotated in ~he opposite direction from the other with the one set being in~ide th~ other.
In Fig. 20, there is shown a partly longi~udinally sectioned, ~fragmentary, simplified view of a hand piece }OC, having as its principal parts an ultrasonic vibrator 40C, a electrical ; rotational motor 40D and a aspirating tube 18C. The motor -40D is t coupled to the ultrasonic vibrator 40C, ,~, ~ : ~ 48 ;: SU~ST~TiJTE Sl lEET (RULE 26) ~;

WO94/21183 ~13 6 3 5 ~ PCT~S94/034~

which in turn is coupled to the aspirating tu~e 18C to impart a combined rotary and longitudinal ultrasonic reciprocating motion to the aspirating tube 18C.
~With this mechanism, the aspirating tube 18C moves ¦the fragmenting tip 14C (not shown in Fig. 20) so that .it rotates rapidly, and while rotating, ultrasonically ,~vibrates in and out of the tissue once for each small, angular increment of rotational motion, such as for example, every one degree or less. Thus, it combines the rotational movement and ultrasonic mavement of prior em~odiments. While the motor 40D is intended to continuously rotate the aspirating tube l~C in a single direction, such as clockwise or counterclockwise, it can alternate rotations, between clockwise and countercloc~wise in the manner of the em~odiment of Fig~
19 . ~
The embodiment lOC of Fig. 20 is similar to prior embodiments in that it includes tubu}ar aspiratirlg connectors 74 and irrigating con~ectors 76 to aspirate through the center: of the aspirating tube 18C and irrigate between the sleeve 12D and the aspirating tube 18C. in the manner described in previous embodiments~

. -~
: : :

S~ TITUl-ESHEET(RULE26) , W094/21183 PCT~S94/03~6_ ~
~3~2 In the embodiment of FIG. 20, the outer shell 60C
encloses both an ultrasonic vibrat~r adapted for reciprocally vibrating the aspirating tube l~C to which the fragmenting tip is connected in a direction aligned with the longitudinal axis of the hand piece and the tip and a rotational motor 40D coupled through a coupled mechanism 150. The necessary electrical connections are supplied through an opening in the rear bulkhead 152.
In Fig. 21, there is shown a fragmentary, sectional view of another embodiment of fragmenting tip 14C having tubular, cylindrical walls 164 enclosing an aspirating section lfi2, which communicates with the interior of the aspir~ting tube 18C (Fig. ;'.0). The end of the tip is rounded at 158 and in one embodiment, may be roughened.
An opening 156, communicates with the aspirating section 162 and ~rovides a slight, inward ~ull of tissue.
To fragment tissue, the slot 156 forms a leading edge and a cutting edye in the walls extending below the rotating portion. This slot may be extended to different depths as desired for determining the area of cavitation. Moreover, there may be a slot in one side of the tubular walls ~t J

, 5 0 ~: ~

Sl)BSTlTUT~ S~ llL~ 76!
~: ~ ' . 1 ~` ` : ': '4 , WO94/211~ ~13 ~ 3 ~ 2 PCT~S94/03~ ~

communicating with the aspirating interior of the fra~menting tip but also, the cavitating edges may be only cut partway into the walls rather than entirely through the walls along their entire length or through only a portion of their length. The slot provides an opening for receiving tissue particles although an opening in conjunction with an edge formed on the surface without penetrating into the aspirating interior of the tube may serve the same function. In operation, the tube is rotated while ultrasonic vibrations are applied along its rotational axis so that it reciprocates in and out of tissue a large number of times ~or each rotation. For example, the rotation may be between 3, 000 and 15, 000 revolutions per minute while lS the ultrasound vibrations may be applied within a range 10 kilohertz to 50 kilohert~. ~he exact frequency of reciprocating vibration and rotational speed may be selected by the ~urgeon and may even extend to lower speeds and freguencies or higher speeds and frequencies depending on the nature of the cataract being :~ fragmented.
he ~ fre~uency of vibration and the ~ speed of - rotation are selected so that the tip moves : i`nwardly into the tissue at every small fraction of ; ' 5l :

~ :SUBSTITUTE SH~ET (R3JLE 26) WO94/211~ . : PCT~S94/03~
~13~352 ` --rotation, such as at every degree of rotation so as to not impart excessive motion to the mass of the tissue but to cause removal of the tissue as a fine powder.
As can be understood from the above description, the technique and equipment of this invention has several advantages, such as: (1) they selectively fragment some tissue without damaging other nearby tissue; and (2) they are able to fragment, mix and aspirate tissue, and in the case of cataract removal, also scrub the capsular wall without damaging it, all with one instrument.
Although a preferred embodiment of the invention . ~ has been described with some particularity, many modi~ications and variation are possible in the preferred embodiment without deviating from the invention. Therefore, it is to be understood that within the cope of the appended claims, the invention may be practiced other than as specifically des~ribed.

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Claims (20)

What is claimed is:

1. A method comprising the steps of:
inserting a surface discriminating fragmenting tip having fragmenting surfaces through an opening in the eye into the lens of an eye having a cataract and a capsular wall wherein the tip has at least one movable fragmenting surface;
moving the fragmenting surface in a first direction and in at least a second direction;
the step of moving the fragmenting surface in a first direction including the step of rotating the fragmenting surface; and the step of moving the fragmenting surface in a second direction including the step of reciprocating the fragmenting surface at ultrasonic speed.

2. A method according to claim 1 further including the stops of:
positioning the surface discriminating fragmenting tip to impact the tissue of the cataract while it is moving at a velocity higher than the fragmenting velocity with respect to the capsular wall and at an angle to the cataract; whereby the cataract fragmented but not the capsular wall; and aspirating the fragmented tissue.

3. A method in accordance with claim 1 wherein the step of rotating the fragmenting surface includes the step of rotating the fragmenting surface in one of counterclockwise and clockwise direction.

4. A method in accordance with claim 1 wherein the step of rotating the fragmenting surface includes the step of rotating the fragmenting surf ace alternately in counterclockwise and clockwise directions.

5. A method according to claim 3 further including the steps of:
positioning the surface discriminating fragmenting tip to impact the tissue of the cataract while it is moving at a velocity higher than the fragmenting velocity with respect to the capsular wall and at an angle to the cataract; whereby the cataract fragmented but not the capsular wall; and aspirating the fragmented tissue.

6. A method according to claim 4 further including the steps of:

positioning the surface discriminating fragmenting tip to impact the tissue of the cataract while it is moving at a velocity higher than the fragmenting velocity with respect to the capsular wall and at an angle to the cataract; whereby the cataract fragmented but not the capsular wall; and aspirating the fragmented tissue.

7. A method according to claim 5 further including the steps of:
making a small incision less than 7 millimeters in diameter in the capsular sac along the margin;
inserting a fragmenting tip and rotating the fragmenting tip to fragment a cataract.

8. A method according to claim 7 in which:
the step of rotating the fragmenting surface includes the step of rotating the fragmenting surfaces about a longitudinal axis of the surface discriminating fragmenting tip; and the step of inserting the tip includes the step of inserting a tip with the longitudinal axis making an acute angle with the capsular wall wherein the rotating fragmenting surfaces impact the tissue of the cataract at an angle.

9. A method according to claim 6 further including the steps of:
making a small incision less than 7 millimeters in diameter in the capsular sac along the margin;
inserting a fragmenting tip and rotating the fragmenting tip to fragment a cataract.

10. A method according to claim 6 in which:
the step of rotating the fragmening surface includes the step of rotating the fragmenting surfaces about a longitudinal axis of the surface discriminating fragmenting tip; and the step of inserting the tip includes the step of inserting a tip with the longitudinal axis making an acute angle with the capsular wall wherein the rotating fragmenting surfaces impact the tissue of the cataract at an angle.

11. A method according to claim 1 in which the fragmenting tip is rotated with a power level of less than 1 horsepower.

12. Apparatus for removing tissue from a patient comprising:

means for fragmenting and aspirating tissue having an operative tip;
said means for fragmenting and separating tissue comprising means for repeatedly moving the operative tip under the control of an electrical signal at a low power level in a first direction and in at least a second direction;
said operative tip having at least one fragmenting edge;
the means for moving the fragmenting surface in a first direction including means for rotating the fragmenting surface; said the means for moving the fragmenting surface in a second direction including means for reciprocating the fragmenting surface at ultrasonic speed.

13. Apparatus in accordance with claim 6 in which the operative tip includes at least two fragmenting surfaces and the fragmenting surfaces include at least one cutting end and one cavitation creating surface.

14. Apparatus according to claim 13 in which the operative tip includes at least two fragmenting edges and the space between fragmenting edges is less than 5 millimeters.

15. Apparatus according to claim 14 in which the operative tip has a diameter of less than 7 millimeters.

16. Apparatus according to claim 9 in which the operative tip is hollow and includes slots extending generally in a plane parallel to the longitudinal axis of the operative time, said slots having a leading edge and a trailing edge.

17. Apparatus according to claim 16 in which the operative tip is replaceable.

18. Apparatus according to claim 17 in which the operative tip is hollow and includes slots extending generally in a plane parallel to the longitudinal axis of the operative time, said slots having a leading edge and a trailing edge.

19. Apparatus in accordance with claim 12 in which the means for rotating the fragmenting surface includes means for rotating the fragmenting surface in one of counterclockwise and clockwise directions.

20. Apparatus in accordance with claims 12 in which the means for rotating the fragmenting surface includes means for rotating the fragmenting surface alternately in counterclockwise and clockwise directions.