exploring and understanding the benefits of torsional phacoemulsification

The News Magazine of the American Society of Cataract & Refractive Surgery

Exploring and Understanding the Benefits of Torsional Phacoemulsification

EYEWORLD SUPPLEMENT MARCH 2006

ModeratorRichard J. Mackool, M.D.

ParticipantsRobert P. Lehmann, M.D.Kerry L. Solomon, M.D.Khiun Tjia, M.D.Sonia H. Yoo, M.D.

Surgical CD IncludedSurgical footage and One-On-OneDiscussions with the Surgeons See back page

An EyeWorld Round table produced live in New York City supported by an unrestricted educational grant from Alcon Laboratories, Inc.

needle. With each oscillatorycycle the distance traveled bythe tip is approximately twotimes greater than the dis-tance (arc) through which theshaft moves. This result is sig-nificantly more delivery ofenergy by the tip to lensmaterial than by the shaft tothe surrounding infusionsleeve and incision. Putanother way, energy createdwithin the incision by the rap-idly oscillating tip is much lessthan at the distal end. Thismode of action represents asignificant thermal advantageand permits the surgeon tocreate a smaller incisionbecause leakage of infusionfluid alongside the ultrasonicinstrument is not required tolower its temperature.

The torsional tip does notmove forward and backward,therefore there is no repulsionof nuclear fragments duringphacoemulsification. Thisundesirable effect of tradition-al ultrasound has required sur-geons to use methods suchas linear power (gradualincrease in tip stroke length)and pulse mode in order tointerrupt ultrasound and,thereby, permit fluid removalto return the chattering parti-cle to the tip of the ultrasonicneedle. They have also usedspatulas and other instru-ments to hold the nucleusagainst the vibrating tip. All ofthese remedies are much lessnecessary with torsionalphaco.

The use of an ultrasonical-ly vibrating needle toremove the nucleus ofthe human lens was intro-duced by Charles Kelman,M.D. in 1968. Since that time,the vibratory mechanism hasremained largely unchanged-the tip of the needle movesforward and backward in a lin-ear direction along the axis ofthe shaft, just as it always hasfor the past 37 years. It is aremarkable fact that thismethodology has remainedvirtually unchanged for almostfour decades while other tech-nologies, such as aircrafts,automobiles, telephones, andother devices, have advancedso dramatically that their cur-rent version bears little resem-blance to their first models.The fact that traditionalultrasound has continued tobe the mainstay of cataractremoval is testimony to therelatively sophisticated originaldesign (fluidics excepted) andthe difficulties in altering theelectronic and mechanicalfeatures of the instrumenta-tion.

A new cataract removalenergy modality on theINFINITI Vision Systemwas introduced at the 2005meeting of the AmericanAcademy of Ophthalmology.Torsional phaco utilizes ultra-sonic oscillations of an angu-lated or curved needle, whichdramatically changes both theenergy profile of the tip andthe reaction of lens materialcontacted by the vibrating

Understanding the Physics ofTorsional Phacoemulsification

Torsional with Different SurgicalTechniques, Post-operative Resultsand Improved Outcomes

Learning Curve and Transitioning to Torsional

Using Torsional on Dense Nuclei

Pearls for Torsional Phaco

Customizing your Lens Removal

Microincision Surgery UsingTorsional

Introduction By Mikhail Boukhny, PhD. and Richard Mackool, M.D.

Traditional phaco Torsional phaco

Richard J. Mackool, M.D.:Im going to compare tor-sional phacoemulsifica-tion to what Ill now refer to astraditional phacoemulsifica-tion. Traditional seems to bethe best word to describe thepast technology that I thinkwe will be doing with less fre-quency in the future becauseof this new, non-traditionalphacoemulsification calledtorsional.

My year-long surgicalexperience has demonstratedthe difference between tradi-tional ultrasound versus therapidly oscillating torsionalmovement at 32,000 timesper second. Its also possibleto use the OZil torsionalhandpiece, alternatingbetween longitudinal andthe torsional motion.

I believe that there aretwo reasons why it is moreefficient in sculpting with tor-sional phaco. First, its cuttingwith each side-to-side motion,not just the forward stroke.While the torsional frequencyis 32 kHz, which is lower thanconventional ultrasound fre-quency of 40 kHz, you willeffectively double the frequen-cy that the tip will remove lensmaterial as each side-to-sidestroke counts twice, so wearrive at an equivalent 64,000cuts per second. In otherwords, it is increasing yourcutting strokes.

The second reason why Ithink torsional phaco is moreefficient is although you dontreally see it when youresculpting the nucleus, densenucleus is actually repulsedslightly away from you. Eachforward stroke pushes it away.The reason you dont see it isit cant go very far. Itsrestrained in the capsule, butit can and does repulse slight-ly away from the tip. So youwind up pushing a little hardertrying to get through it.Torsional stroke is side to sideso it shears the lens materialand doesnt make it move

away from the tip. I thinkthats why were seeing suchgreat advantages, even duringthe sculpting process, and, ofcourse, during the nuclearsegment removal. Anybodywho has done any phaco willimmediately see the lack ofrepulsion as the main benefitof torsional, and it is just offthe charts.

Torsional phaco can becombined with a number ofinfusion sleeves: a 3.0 to 2.75mm incision utilizing the 0.9high infusion sleeve, or thenew Ultra Sleeve, which fitsvery easily through a 2.2-mmincision.

I recently operated on theonly eye of a patient with anextremely dense nucleus andan endothelial cell count of412 cells/mm2. There was nosignificant zonular support,and I used the CataractSupport System. The nucleuswas a dense red brown, buteven so there was simply nochattering of nuclear pieces.

Even with such a marginalcornea cell count and denselens, the patients cornea wasclear immediately andremained so. What was partic-ularly noteworthy was theabsence of chattering. Evenwith the patients very denselens, cataract fragments onthe tip didnt bounce away.

I also recently performeda case on another patient with4+ corneal guttata and fewerthan 500 cells/mm2. Again,this patient underwent a tor-sional procedure using a miniflared tip and an Ultra Sleevethrough a 2.2-mm incision. Iused a standard phaco choptechnique, applying 250 mmHg, to impale and hold thenucleus. I then used 400 mmHg to remove the nuclear seg-ment. The ability to use thesevacuum levels when operatingthrough such a small incisionis unique to the InfinitiTM fluidicsystem.

The thermal benefits oftorsional are such that, in my

2 Exploring and Understanding the Benefits of Torsional Phacoemulsification

5 seconds fully occluded, no flow situation at 100% torsional amplitude and100% ultrasound power

Anybody whohas done anyphaco willimmediately seethe lack ofrepulsion as the main benefit of torsional, and it is just off thecharts

Richard J. Mackool, M.D.

Understanding the Physics of Torsional Phacoemulsification

7.5 seconds fully occluded, no flow situation at 100 % torsional amplitude and100% ultrsound power

Richard J. Mackool, M.D., isdirector, Mackool Eye Institute,and senior attending surgeon,The New York Eye and EarInfirmary, New York.

A Supplement from an EyeWorld Round Table held live in New York City 3

opinion, theres greatly reduc-ed risk of creating an incisionburn. Weve done thermalimaging studies using infraredthermography and have foundthat is extremely difficult tocreate incision temperaturesapproaching those necessaryto burn the incision.

The simplest way to makephaco easier is to use tight,non-leaking incisions. Theeasiest way to make it verydifficult is to have leaking inci-sions. There are no disadvan-tages and almost no learningcurve to torsional. It has apretty impressive list ofadvantages. Those advan-tages will become obvious tothe surgeon who takes up thistechnology. I would say that

the surgeon will see theadvantages in a very shortperiod of time, if not withinthe first few cases.

Robert P. Lehmann, M.D.:Dr. Mackools surgical casesshow that theres very littlemovement of the torsional tipin the eye because the mate-rial seems to flow to the tipbetter with torsional than withany other instrument Ive everused, from the AquaLase

Liquefaction device toNeoSoniX handpiece to stan-dard phaco. Lens material justflows into the tip and is emul-sified. Also, I found that mynext quadrant actually comesto the tip better and you rarelyneed to reposition the tip to

attract the nucleus or manipu-late nuclear fragments with asecond instrument. Nuclearfollowability is unparalleled.Dr. Mackool: When nuclearfragments are not repelledand dispersed, there is lesschance that small fragmentswill get trapped in the angle,capsular fornix, or sulcus.Youre probably less likely toleave material behind.

Kerry L. Solomon, M.D.: Ithink its more efficientbecause you actually are nowusing a totally new movementthat is cutting with both direc-tions of tip movement. The tipmoves in a side-to-sidemotion, so it is in constantcontact with nuclear material.

When you use traditionalultrasound, the movementonly cuts in one direction for-ward. Therefore, it doesnt cutmaterial efficiently. With tor-sional phaco, the materialstays at the tip. For that veryreason, I think the lens materi-al just emulsifies much moreefficiently than with traditionalultrasound.

Dr. Mackool: Traditional ultra-sound can only cut on the for-ward stroke. The backwardstroke is just getting ready foranother forward stroke, yetthe backward stroke con-tributes to thermal energy atthe incision every bit as muchas the forward stroke.

Dr. Solomon: In a nut-shell, my post-operativeoutcomes have beenexcellent. Ive been verycomfortable with my tech-niques and my corneas areclear. My standard ultrasoundprocedure is the InfinitiTM, witha 1.1-mm Kelman flared tip.The move for me to torsionalwas one that, at first, I wassomewhat skeptical about,because I was alreadyachieving great results. I wasreally looking forward to try-

ing it, though, because I thinkthere are a number of veryclear advantages for why thisought to be the direction wego.

As weve discussed, tor-sional phaco allows less riskof thermal injury, less disper-sion of nuclear fragments,and improved efficiency.Speed is not its only efficien-cy; safety is as well. Theseclinical advantages are huge.If you look at the trend ofwhere were going with our

surgical techniques, weregoing toward smaller inci-sions. If we go toward smallerincisions, then we need to bemore concerned about ther-mal risk.

Certainly, we try to intro-duce less irrigation fluid intothe eye, so we need to beconcerned about efficiency,maintaining as efficient a sys-tem as possible. Also, wewant to be able to keeppatients corneas clear. Tome, that depends on turbu-

lence and better efficiency atthe tip, with less dispersion ofnuclear fragments. I think themotion of the tip generatessignificantly less energy sim-ply because of the way itoscillates, rather than back-ward and forward, whichalready has been mentioned.

In reviewing cases, wecan see lack of dispersion ofnuclear material. Its evidentwhen you first start emulsify-ing or harvesting your lensmaterial theres really no

Torsional with Different Surgical Techniques, Post-operative Results and Improved Outcomes

Repulsion from traditional ultrasound Little or no repulsion from torsional phaco


I have found this to be veryeffective. You get a slightlywider trough because of theaction of the tip, which reallycauses no downside, yet theupside is efficient quadrantremoval when it comes timeto harvest the lens quadrants.For stop-and-chop surgeons,again, you get a slightly widertrough because of the torsion-al action but very efficientquadrant removal.

For pure chop surgeons, Ithink you can do one of twothings. Ive experimented a bitwith using traditional ultra-sound to quick chop andmake the initial pieces. I havegotten better purchasingpower with traditional ultra-sound for that because theback-and-forth movementhelps me to penetrate andimbed the phaco tip into thenucleus. I then change to aquadrant removal setting anduse 100% torsional phaco,except for very dense lenseswhere we may introduce somesmall percentage of ultra-sound for quadrant removal.

As for cataract density,soft lenses, you can aspiratethem out. I can have anabsolutely watertight seal onmy phaco incision and awatertight seal on the para-centesis incisions (or almostwatertight) and find the effi-ciency is huge. On soft lenses,torsional phaco is incrediblysafe. The chamber doesntmove at all and there is littleor no energy whatsoever.

Weve monitored andmeasured my fluid usage percase, and it varies from about25 to 50 cc per case. Thatstotal fluid throughout the case,including irrigation and aspira-tion, and that just simplyspeaks to the efficiency of thesystem.

I think we need to makesure we dont overlook what awatertight incision does forus. It not only improves theefficiency of the systembecause its preventing mate-rial coming up to our differentincisions when were trying tobe efficient in the center, italso improves the fluidics driv-ing everything right to the tip. Ithink it will allow us to evenuse lower parameters andmaintain just as good efficien-cies through smaller incisions.The bottom line, too, is stable,rock-solid chambers.

As for soft lenses anddense nuclei, I think you canuse torsional on both. This isreally technique independent,or cataract-density independ-ent. In many instances, I thinkthis makes an average sur-geon better, and its reallygoing to show its truest colorsin the moderate to densenuclei.

I think you can use yourfluidics any way youd likebecause the efficiencies of itare such that its going toshine both with a low flow andhigher flow settings. I tend toprefer the high-flow phacoaspiration technique.However, as Ive movedtoward smaller incisions, Ihave reduced my fluidicparameters based on incisionsize and the particular tip thatI use. For example, I found Ican use slightly higher param-eters with a mini-flare tip com-pared to the tapered tip.

In summary, I think tor-sional gives us less thermalrisk and more efficientremoval of lens material. Thatreally means less repulsion,and no forward-backwardmovement of the lens materialor the tip itself. The materialjust stays right at the tip forquick movement. It offers bet-ter fluidics, which is not to be

repulsion, no forward or back-ward movement of the tip. So,as weve discussed previous-ly, the lens material just staysright at the tip and, in myexperience, just vaporizes.

I think torsional is moreefficient because the tip cutswith both movements.Because the material stays atthe tip, you dont have to goaround the anterior chamberand chase it.

Again, if were progress-ing toward smaller incisions,we dont want to have to sac-rifice operating efficiency. Wedont want it to be less safe,cause thermal injury, increasecapsular tear rates, or haveother downsides. We dontwant huge learning curves nordo we want to slow down ourprocedures. Ideally, wed liketo be able to have a learningcurve thats minimal or zeroand be able to maintain effi-ciency while we create smallerand smaller incisions.

This torsional technologyis ideally suited for that. Thathas been my experience as Ihave transitioned from a 3.0-mm incision with my 1.1-mmflare, down to a 2.6-mm usingthe 0.9 tapered tip and to a2.2-mm incision with a newmini flared tip that is underevaluation. This has all result-ed without me needing tomodify my surgical techniquesor procedures.

I think this technologylends itself to all-comers. Fordivide-and-conquer surgeons,

Material stays at the torsional tip

As wevediscussed,torsional phacoallows less risk ofthermal injury, lessdispersion ofnuclear fragments,and improvedefficiency.

Kerry L. Solomon, M.D.

Kerry L. Solomon, M.D., isassociate professor of oph-thalmology, Medical Universityof South Carolina, Charleston.


Sonia H. Yoo, M.D.: Themain technique Ivechanged to be able touse torsional ultrasound isusing 0.9-mm angled Kelmantip instead of the 1.1-mmstraight flare tip.

The change to torsionalphaco and the different tipdesign have required someadjustment in my surgicaltechnique. I also have beengoing from pulse or burstmode in my quadrant removalwith traditional ultrasound to acontinuous torsional ultra-sound mode to maximize theefficiency of this new tipmovement.

In one of my first cases,the patient had a fairly dense3+ cataract. At that time, Iwasnt quite used to using the0.9-mm tapered tip. Itrequired me to make morepasses than I was used towith the 1.1-mm flare tip.However, having a thin grooveallowed me to crack thenucleus a little easier, particu-larly with these denser nuclei.I found it was fairly easy toocclude the tip and bring thepieces right to me, thus keep-ing the phaco tip in the centerof the central safe zone.

I did have to make a littlefoot adjustment with tradition-al ultrasound. I would movequickly into foot position threeand just engage the nuclearpiece with a low amount ofultrasound. But with torsional,I found that just holding it infoot position two, really turn-ing the tip of the needle flushwith the nuclear piece, andthen building occlusion at the

top of two was all I needed.This allowed me to move thepiece and activate torsionalultrasound. Also, I didnt getthat repulsive effect you cansometimes see with traditionalultrasound. I automaticallystarted removing lens materi-al.

A later case in which Iused torsional was anotherfairly dense cataract in apatient with a moderatelydilatable pupil in the diabeticeye and a bit of a floppy iris. Imade somewhat of a transi-tion. I had to take a little bitmore time to do that initialsculpt because Im generally astop and chopper. However,the smaller groove made thecracking easy, and I wasagain very impressed with thatthe pieces would just come tothe tip and stay at the tip. Ididnt have to reach or fish forthem in the periphery. I couldjust stay in the middle of theeye.

I also found that thereseemed to be less chatter ofthe pieces than I found withtraditional ultrasound. Theonly time I would get occa-sional loose particles waswhen my paracentesis was alittle too large, so I had someegress of fluid out of the para-centesis, and occasionally Iwould get a little chip in thenucleus out at the incision. Ithink that was more a functionof my second port incisionsize than anything else.

Then, I used it on a softlens. I was using the pre-chopper in a soft lens, justturning it upside down, and

was able to crack it prettyeasily. The main part of thetechnique that took a little bitof adjustment for me wasrather than going right intophaco three and engaging thepiece. I could just hold at thetop of two and engage thepiece that way. Then every-

thing would stay right at thetip.

Because I am at a teach-ing institution, I have theopportunity to operate withfellows on my surgical days.My fellow was easily able touse the torsional as well. Weexperimented with quick

Learning curve and Transitioning to Torsional

Creating a central groove with torsional phaco

OZilTM Torsional handpiece with the tapered Kelman angled tip

understated. You must payattention to your incisions toachieve that, but that reallyhelps with the efficiency.

The torsional is very flexi-ble for all techniques, allcataract densities, and itsideal as we move towardmore watertight incisions forrefractive lens exchanges aswell as dense mature

cataracts. This is the perfecttechnology to match as wemove toward smaller inci-sions. Im not sure where theendpoint is, but torsionalphaco is the technology thatwill take us there.

Dr. Mackool: Another situa-tion Id like to comment on is

a floppy iris. When you oper-ate with a tight, sealed inci-sion, you dont have turbulentflow. These floppy iris syn-dromes usually associatedwith Flomax (BoehringerIngelheim GmbH, Germany)are much easier to manage.You can use lower vacuumlevels, as we discussed. That

tends to keep the pupil moredilated and the iris is less like-ly to be attracted to the tip.There are a lot of advantagesin these Flomax-type casesfor using this kind of sealedincision, lower flow, andvacuum, yet still remove thecataract efficiently with tor-sional energy.


chopping and stop and chop,and the torsional worked veryefficiently for all these differentkinds of maneuvers and wasvery safe. From a teachingstandpoint, Im very happywith the safety of this torsionalultrasound.

Dr. Mackool: You commentedabout using torsional in con-tinuous mode. Continuousphaco during removal ofnuclear segments hasbecome more or less passwith the vast majority of sur-geons. In other words, tradi-tional ultrasound is usuallypurposely interrupted becausetheres a tendency for parti-cles to chatter away. If youinterrupt ultrasound, you canreattract nuclear material tothe tip, and then the nextburst comes along and hitsthe nuclear segment, emulsi-fies it, and the process isrepeated. With torsional ultra-sound, you dont get chatter-ing.

Torsional doesnt have therepellent force, so if you inter-rupt delivery of energy, theremoval process stops with-out benefit because the pieceis still on the tip. Delivery oftorsional power is linear,meaning greater torsional tipexcursion. Excursion occursas the foot pedal is depressedfurther. The use of continuousmode is not so much a learn-ing curve as a new way ofthinking about how to apply

ultrasonic energy with torsion-al compared to how we applyit with traditional ultrasound.

Khiun Tjia, M.D.: Touchingupon the issue of teaching,you mentioned the increasedmargin of safety. I also teachresidents. Although I havenever experienced any woundburns myself, I have wit-nessed two very difficultwounds, after phaco by a resi-dent, which were almostimpossible to close. I thinkthat type of burn is veryunlikely when torsional isused. Thats a great comfortto residents, as well as to theteacher.

It also decreases the rateof posterior capsular ruptures.Ive experimented with vacu-um and aspiration flow set-tings with torsional. I foundyou can lower vacuum set-tings and aspiration flow set-tings significantly, by as muchas half. But, even with theselow flow and vacuum parame-ters, you still have much moreefficiency compared to tradi-tional longitudinal ultrasoundwith more aggressive fluidicsettings. Because of lowervacuum and aspiration flow,you have an enormous marginof safety and rock-solid ante-rior chambers. That allows forvery easy quadrant removalby residents without the fearof getting a capsule up to thetip after occlusion break. With

this technology, that is simplyeliminated.

You also experiencereduced chatter of lens mate-rial because the forwardstroke of longitudinal ultra-sound is indeed eliminated. Inaddition, when torsional ultra-sound is used, the surgeon isnot chasing particles any-where around the anteriorchamber. This technologygives residents control of theprocedure. Their self-confi-dence grows enormouslywhen they use this. This tech-nology will be a major leapforward in cataract surgerytraining of residents. It willalso increase the quality oftheir cataract surgery.

Dr. Solomon: One of the bar-riers to bimanual surgery, evenfor experienced surgeons, hasbeen a long and steep learn-ing curve. If we look at how tomake phacoemulsificationbetter, we want to make itmore efficient and safer.

By being able to take afellow, a resident, an averagepractitioner, or an experiencedpractitioner and require essen-tially little to no learning curveto change over to torsional ishuge. We have residents whouse torsional and my otherassociates have used torsion-al. Theres little to nothing newfor them to learn in order tosuccessfully use the technology.

Were okay loweringparameters within the eye ifwe want to or need to, or aswe go to smaller incisions, aslong as the action of the tip iskept efficient. I think the effi-ciency with torsional is greaterthan with ultrasound, evenwith lower parameters. Youcan use lower flow and lowervacuum, higher flow, highervacuum, soft lens, and densecataracts, with very littlelearning curve.

Dr. Mackool: At ourAmbulatory Surgery Center,we have introduced torsionalto a number of surgeons;some of them do phaco chopand some do divide and con-quer. Every surgeon com-mented, I want to use this on

Pieces of nucleus just come and stay on the torsional tip

From ateaching standpoint,Im very happy with the safety of thistorsionalultrasound.

Sonia H. Yoo, M.D.

Sonia H. Yoo, M.D., is assis-tant professor of ophthalmolo-gy, Bascom Palmer EyeInstitute, University of Miami.


every patient. This has creat-ed an interesting problem forus. Weve got to get more ofthese machines because wehave four ORs and only twoInfinitiTM machines equippedfor torsional.

Dr. Lehmann: Dr. Yoo hasalluded to something that shenoted using a 1.1-mm tip.With torsional phaco, we usea smaller tip, and thats prob-ably the only change that Iobserved. I find that to attractthat first quadrant after Ivemade a crack is different withtorsional. Because the tor-sional tip has less repulsion, itwill just go right into thenucleus. It will just shear thelens material and remove thenucleus. What you want to dois attract that first piece ofnucleus into the central zoneof safety.

Ive actually moved tomore pre-chopping in themoderately dense nuclei. Imthinking about using Dr.Mackools stop-and-choptechnique and cracking thelens into five or six pieces,which Ive never done. Ivealways grooved first and thendone a bimanual in situ phacofracture technique. The effi-ciency with which the tip justerodes the nucleus is almostlike magic. Dr. Solomon, madea comment about how it justvaporizes the tissue; once thattissue starts to come to the

center of the zone of safety,the center of the eye, its justcomplete followability, whichis wonderful.

Dr. Tjia: Another observationis production of lens milk-especially during sculptingwith continuous torsionalultrasound. I think the reasonit occurs is that the transversemotion of the tips preventsemulsified milk to escapethrough the constantlyoccluded tip end. Once a sur-geon repositions or withdrawsthe tip, it will egress very easily.

Dr. Mackool: Yes, and thatwould be very different thanseeing this lens milk duringsculpting with traditional ultra-sound. With traditional ultra-sound, the surgeon thinks,Oh, the tip is completelyobstructed. There is no flowanywhere in the eye. I want tobe careful that I dont createan incision burn. This is notthe case with torsional. Lensmilk is a curiosity of this newmovement, and it is not aproblem.

Dr. Solomon: Dr. Mackool,you brought up a point whereyou mentioned endothelial cellcounts and how clear thecorneas looked. I think whenyou look at the studies of flu-idics with torsional, we shouldbe able to see less turbu-lence, perhaps greater reten-

Greatly improved thermal safety profile is beneficial when sculpting on denselenses

Using Torsional on Dense Nuclei

Dr. Tjia: As Dr. Mackoolhas already discussed,softer lenses, and somemedium lenses, can be takenout with just vacuum alone,without any ultrasound. Ondenser nuclei that was not thecase. I think torsional is ofimmense importance in thosecases.

Summarizing the benefitsof torsional are the low tipmovement and the reducedthermal friction at the woundsite stressing again the poten-

tial for thermal injury even with100% continuous torsionalultrasound is actually almosteliminated even on the dens-est of lenses.

The other major advan-tage is the very effective trans-verse motion and, therefore,continuous contact betweenthe tip and the nucleus. Asalready said, because of main-taining the occlusion all thetime, the reduced flow and tur-bulence in the anterior cham-ber keeps our endothelial cellsin much better shape. That is

Lens milk can occur during torsional emulsification

Torsional increases efficiency and reduces turbulence even on dense nuclei

tion of viscoelastics, better forthe cornea and endothelialcells in terms of corneal pro-duction.

Dr. Mackool: We have a studyunder way now to compareour cell-loss rate that, Imhappy to say, had gotten quite

low with traditional ultrasoundperformed through a sealedphaco incision. Torsionalallows sealed incisions, justlike Ive been used to usingwith my Mackool system;however, there are additionaladvantages such as lessrepulsion and turbulence.


not only because of thereduced turbulence but alsobecause we keep the protec-tive viscoelastic in the anteriorchamber much better than ifwe use traditional ultrasound.

I have compared tradi-tional ultrasound and torsionalin numerous cases. In onecase, however, I was confront-ed with a pretty tough nucleusand a mature cataract. I usedtraditional ultrasound and lin-ear burst mode, with U.S.power up to 60% and a maxi-mum duty cycle of 20% forquadrant removal.

I didnt schedule thispatient for torsional because Ididnt actually think that itwould be that hard. But afterthree quadrants using tradi-tional ultrasound, I asked for atorsional handpiece.

The last quadrant wasemulsified at a stunning speedand the difference in efficiencybetween longitudinal and tor-sional ultrasound was striking.

Knowing what is possiblewith torsional puts us in awhole different ball game.

Although other tips canwork, my personal experiencehas been best with a taperedKelman, 45 degrees. I have

had some cases where alter-nating torsional and longitudi-nal can be beneficial. In mostcases, 100% continuous tor-sional is just excellent. Withvery hard nuclei, torsionalultrasound has made my workas a cataract surgeon a wholelot easier.

I had an early case abouta year ago with a really darkbrown nucleus. This wouldhave scared me before tor-sional. It was sticky, cheesy,rubbery, and hard. Duringsculpting this extremely hardnucleus I wasnt afraid ofburning the incision, even with100% continuous torsional.

With a really dense andrubbery nucleus like this one,simple cracking is impossible,and I had to perform slowchop. After every successfulchop, emulsifying the brownnuclear pieces was strikinglyefficient and easy. With tradi-tional ultrasound it would havebeen extremely difficult andtime consuming to removethis cheesy lens material witha serious chance of cornealdecompensation.

The outcome of this casewas excellent, thanks to tor-sional technology.

Dr. Lehmann: The rubbery,Coca-Cola cataracts youdescribed are in patients withpoor dilation and weakzonules. In many cases theseare managed with muchgreater ease using torsional.This fact has really made myoperating room day far lessstressful because torsional issafer, more efficient, and notjust in those cases for allcases. Youre not manipulat-ing nuclear fragments asmuch. There is less repulsionand therefore less chatter andI think youre stressing thezonules and your cardiac cir-culation much less.

Dr. Yoo: I sometimes use the45-degree tip, too. I went fromthe 30- to 45-degree tip andthought it worked very effi-ciently. It was very quickremoving the quadrants in ahigh vacuum mode.

For many of these densecataracts, we used NeoSoniXbefore. The difference sur-geons get with NeoSoniX ver-sus the torsional ultrasound interms of lack of repulsionmakes such a difference.Ergonomically, the handpieceis much lighter and it worksmore efficiently.

Knowingwhat is possiblewith torsionalputs us in awhole differentball game.

Khiun Tjia, M.D. OZilTM Torsional handpiece is ergonomic and lightweight

Khiun Tija, M.D. Isala Clinics,Zwolle, Netherlands


Dr. Mackool: Even if you per-form traditional ultrasound,you really want your quad-rants to be free so that stressis not transmitted to the cap-sular sac and zonule whenyou try to remove a quadrantthats still attached to the restof the nucleus.

Customizing your Lens Removal

Pearls for using torsional phaco

Dr. Tjia: There are somesituations where a phacotip has the tendency tolollipop or Swiss cheese thenucleus; the nuclear quadrantwill be stuck onto the phacotip and it cannot go inbecause its stuck by thesleeve. A 45-degree tip worksa bit easier than the 30-degree tip because a 45-

degree angled tip makes thequadrants tumble more easilythan a 30-degree one.

Another option is to addintermittent short bursts oflongitudinal ultrasound.Because of the short repul-sive effect of longitudinalultrasound, the quadrant willbe repositioned and will facili-tate the quadrant to be tum-

Dr. Lehmann: With theInfinitiTM Vision Systemslaunch we hadAquaLase, standard phaco,and NeoSoniX. I see torsionalpretty much replacingNeoSoniX and traditionalphaco in my practice.However, I think there is still arole for AquaLase.

Were seeing a widervariety of lens densities nowcoming into play becauserefractive lens exchange withpresbyopic lens correctionhas become a large part ofour practices. We have somenew anatomical variationsrecognizing the associatedproblems that we see withintra-operative floppy iris syn-drome and Flomax. Also, anincreasing occurrence ofpost-refractive patients, post-LASIK and RK patients com-ing in that are in the babyboomers, developing theircataracts. Increased patientexpectations are a result ofthe presbyopic procedures.Those overall higher expecta-tions come with no shot, nostitch, no patch refractivecataract surgery.

The improvements havebeen monumental, and wesee many younger patientscoming in now wantingcataract removal at an earlierstage. Depending on the geo-graphic area of your practice,there are still a large number

of patients that come in withvery advanced, very hardcataracts. I think it is in thepatients and surgeons bestinterest to optimize thepatients results by perform-ing whatever technology issafest and most efficient forremoval of their lens cataracttype.

I use AquaLase for all ofmy refractive lens exchangecases and for patients withprimarily posterior subcapsu-lar cataracts, and softer, up toa 2+, dense nucleus. I thinkthere are some distinctadvantages to AquaLase,even over torsional, becausethe metal needle within theconfines of the capsular bagis still not as smooth, deli-cate, and safe to the posteriorcapsule as the smooth poly-mer AquaLase tip.

We went through a timewhen we initially sculpted andcracked and now implementa pre-chop with greater effi-ciency. The result is thatAquaLase, now with pre-chop, is much more efficientand quicker in terms of speedand safety in those softernuclei. The tip is more cap-sule-friendly than the metalneedle. Pre-chopping allowsme to predetermine a casethat might be good forAquaLase, or might not be,and if I have a problem crack-ing the posterior plate with

bled and emulsified withoutbeing lollipopped.

Surgeons have to beaware that the quadrantshould be really free andmobile and not be blocked bythe capsulorhexis edge, iris,or cornea. It should be able tomove freely. If it cannot movefreely, it cannot tumble furtherand be emulsified.

Torsional increases nuclear followability

Using continuous torsional increases efficiency of emulsification

the soft cases. I do not thinknecessarily the torsional tech-nology is as safe within theconfines of the capsular bagas the smooth AquaLase tip,in the very soft lenses particu-larly. In refractive lensexchange, Im sticking withAquaLase-at least for now. Ifall you had was torsional ver-sus traditional phaco, I willpredict we are going to see a100% conversion of physi-cians who try the technologyof torsional and appreciate allof its advantages.

Dr. Tjia: I agree aboutAquaLase having a very defi-nite role to play in lens sur-gery. As you indicated, refrac-tive lens surgery will becomemore important. The remoteaction of the AquaLase spray,the power-washing of thecapsule, is something noother technique can do.


the pre-chopper, I will simplyuse torsional.

If we consider efficiency,as Dr. Solomon mentioned, afunction of not only time andspeed, but safety, I think thatthere is still a definite role forAquaLase.

Again, I use torsional formy medium to dense lensesbecause torsional has greaterefficiencies that I think willquickly become evident tosurgeons. The repulsive forcesof longitudinal phaco willeventually be repulsive to sur-geons that have the opportu-nity to use torsional. As Dr.Mackool mentioned, there isno downside. There is very lit-tle learning curve and no safe-ty tradeoff. Torsional is justmore efficient. There is lessturbulence and better followa-bility. I think it was probablyDr. Kelman that at some pointin the past made a commentthat the ideal tool were look-ing for is an instrument that

we can put in the eye, engagethe cataract, and the cataractmaterial will be drawn to itand eliminated. Torsional is asclose as it gets to that idealtoday. Dr. Solomon has usedthe term vaporize, and that,perhaps, doesnt give just theright picture that we want toportray. But literally, thecataract tissue is removedfrom the eye so smoothly andefficiently that there is moreretention of viscoelastic, and agreater margin of safety, andwe see incredible outcomesday one.

Harkening back to thepatient population that wehave now with greater expec-tations, this is a requirement.This is no longer a luxury. Butwere able to achieve thesekind of outcomes more easilyand reliably with torsional.

Customization is impor-tant. If a surgeon has theInfiniti available, certainly ven-ture out and use AquaLase in

Microincisional Surgery Using Torsional

I see torsionalpretty muchreplacing NeoSoniXand traditionalphaco in mypractice. However,I think there is arole forAquaLase.

Robert P. Lehmann, M.D.

Robert P. Lehmann, M.D., isclinical associate professor ofophthalmology, Baylor Collegeof Medicine, Houston.

Dr. Mackool: Dr. Tjia,where are we now withincision size? How lowcan we go?

Dr. Tjia: If we are talkingabout microincisional cataractsurgery, I think its still acataract implant issue. Whatincision size is needed for aspecific implant? There are,specifically in Europe, moresmall-incision, microincision,implants available. Whetherthey are very good or have along-term follow-up is ques-tionable. I think that is not yetthe case.

If we are talking aboutproven good quality implants,then the AcrySof single-piecehas been implanted aboutover a year through smallerincisions. I think the smallestpost-injection incision sizedocumented is in the order of1.9 mm. Specifically, a sur-geon in Japan, Dr. Akahoshi,has done thousands of thosecases, but his technique is

potentially a bit moredemanding than is possiblefor every average surgeon. Atpresent, 2.2 mm is a goodincision size to rely on.

Until recently, microinci-sional surgery was bimanualphaco with longitudinal ultra-sound. Several companieshave promoted this. In fact,every single machine can doit.

We have already dis-cussed the drawbacks of tra-ditional ultrasound heat pro-duction, repulsion by the lon-gitudinal stroke, and thereduced irrigation flow.Another major issue, distortionof the 2 tight corneal incisionsby the rigid metal cannulas,withheld me from pursuingbimanual phaco.

Manipulating the hardcannulas within the tight inci-sions certainly distorts andcompromises the incisions.

Clear corneal incision isalready controversial becauseof the possible increased

endophthalmitis risk. Thatscertainly not better with dis-torted wounds. Micro-coaxialphaco with a soft and mal-leable Ultra sleeve doesntdistort the incision, especiallythree-step traditional woundconstruction, which seems tobe very strong and safe.These three step wounds,after applying point pressurejust behind the wound lip,remain watertight. A properlyconstructed non distortedincision should be 100% safe,but with microcoaxial phaco itshould even be stronger,because of the smaller size ofthe incision.

I created a video thatshows a comparison, withinthe same procedure, of tradi-tional versus torsional ultra-sound. In the clip, you see a2.0mm incision, micro-coaxialphaco with an Ultra sleeve.

First I used traditionalultrasound and pulse mode,and a reduced aspiration flowof 30 ml/min (instead of


Dr. Mackool: I want to compare biman-ual, so-called microincision cataractsurgery (MICS), with micro-coaxialphaco. With the bimanual technique, sur-geons generally create two incisions of 1.5mm. With the Ultra sleeve and torsionalphaco, they can create one incision thatcan be anywhere from 1.8 to 2.2 mm andwill not leak during phaco.

With the current MICS technique, anadditional incision is required for IOL inser-tion. Most surgeons make an additionalincision for this because they essentiallydistort the first two incisions so much thattheyre afraid that enlarging them will makethem incapable of self-sealing. That addsanother 2.5 to 3 mm. With micro-coaxialphaco using the Ultra Sleeve, no additionalincision is needed for IOL insertion.

With bimanual MICS, the phaco inci-sion must leak in order to cool the needleunless the surgeon uses a special Mackooltip for MICS through a non-leaking incision.The majority of surgeons using other instru-mentation from other companies performMICS with an incision that leaks. Withmicro-coaxial phaco with the Ultra Sleeveor any other sleeve you care to use, theincision can be watertight and it should be.Theres no reason to have it leak.

With the bimanual procedure, theres apretty steep learning curve. Different instru-ments are required. Many surgeons havereported that they find no advantages withit, its market penetration has been minimal,and there are apparently good reasons forthat. With micro-coaxial phaco using theUltra Sleeve, or any other sleeve for thatmatter, weve found no learning curve.These are compelling arguments in favor of

Bimanual versus Micro-coaxial Cataract Surgery

by Richard J. Mackool, MD

small, micro-coaxial surgery compared withbimanual surgery.

When an incision is smaller, and in thecase of smaller coaxial tips, we certainlyhave smaller incisions, theres less infusioncapacity, meaning less flow can be deliveredto the eye. When that happens, lower flowand vacuum settings must be used com-pared to procedures done with a larger inci-sion and larger infusion sleeve. This couldreduce efficiency if everything else remainedthe same. However, because torsional does-nt repel nucleus, high flow and vacuum arenot required to attract and hold it. Therefore,the efficiency of the procedure doesnt sufferdespite the fact that reduced flow and vacu-um settings are employed. Thats a hugeplus.

Another advantage is the undeniablebenefit of a malleable (silicone) infusionsleeve. With the bimanual technique, theinfusion cannula and the phaco tip are rigid.These round, unyielding instruments undesir-ably stretch and deform the incisions. If youput an infusion sleeve on them, they wouldrequire a larger incision.

45ml/min with a micro sleeveand 2.75mm wound). There issome chatter, due to thereduced flow. In the secondquadrant, I used Burst modewith a very low duty cyclewithout significant chatter. Itwas gradually emulsified. Butthe third and fourth quadrantsI removed by using 100%continuous torsional ultra-sound with far greater andstriking efficiency, even withthe reduced aspiration flow.This represents a huge differ-ence in surgical effectivenessand lack of repulsion com-pared to traditional ultra-sound.

At the end of this proce-dure I had a 2.1-mm final inci-sion size, and without havingstromally hydrated the wound,and without any significantwound stretch. It is 100%watertight.

In conclusion, the superbefficiency and intrinsic safetyof torsional ultrasound willmake the transversion from2.8mm coaxial phaco to2.2mm micro-coaxial phacovery easy.

Cataract surgeons nowhave the option of performingsafe and efficient MicroIncisional Cataract Surgerywith proven high quality 6 mmoptic IOL injection.

Dr. Mackool: Id like to thankeach of my distinguished col-leagues for sharing his insightand experience regarding tor-sional phacoemulsificationwith our colleagues. Its obvi-ous that the entire panel isconvinced that this technolo-gy dramatically improves thephacoemulsification proce-dure.

12

This supplement was produced byEYEWORLD under an educationalgrant from Alcon Laboratories Inc.The views expressed here do notnecessarily reflect those of the editor, editorial board, or the publisher, and in no way implyendorsement by EyeWorld orASCRS.

Copyright 2006 ASCRS OphthalmicCorporation, All Rights Reserved.

Printed in United States

Included with this supplement is a CD that containssurgical footage and detailed discussion of manyimportant aspects and applications of the torsionaltechnology. All five participants discuss, use, anddemonstrate torsional phaco so you can better visual-ize the exciting potential and benefits of this new andunique lens removal modality.This CD was produced and directed solely by Alcon Laboratories, Inc., and was not taken from this EyeWorld Supplement.

The efficiencywith which thetip just erodesnucleus is almostlike magic.

Robert P. Lehmann, M.D.

Richard P. Lehmann, M.D., isclinical associate professor ofophthalmology, Baylor Collegeof Medicine, Houston.

INF131

exploring and understanding the benefits of torsional phacoemulsification

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