cover story pearls for cataract for cataract · may 2009i cataract & refractive surgery
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MAY 2009 I CATARACT & REFRACTIVE SURGERY TODAY EUROPE I 1
INTRODUCTIONNo two cataract surgeries are alike. Although some cases
are uncomplicated and progress smoothly from start to fin-ish, others are plagued with complications that require thesurgeon to make difficult decisions.
The lesson all cataract surgeons have learned at somepoint is that there is no standard technique that can beused for all procedures. It is best to adjust your tech-nique depending on the case and the cataract type. Inthis article, key opinion leaders in cataract surgery offertheir pearls for cataract removal in soft, medium, andhard cataract cases. As most imply, you must be able tochange your strategy at any time to achieve the optimaloutcome in any given case.
DAVID ALLEN, FRCS, FRCOPHTHSoft cataract. These can be challenging for the begin-
ning surgeon. The danger is being left with a posteriorplate of epinucleus and cortex, which is difficult toremove. To avoid this, perform careful cortical cleavinghydrodissection followed bymultiple attempts at hydrodelin-eation (Figure 1) in different lay-ers. It is often possible to sculptthrough to reach a small nucleus(Figure 2) that is easily con-sumed. Then, different layers ofsofter material can be repeatedlyremoved using the flip tech-nique, made popular by I.Howard Fine, MD, of Eugene,Oregon.
Medium cataract. My pre-ferred technique is horizontalchopping; however, the follow-
ing pearl is also applicable to the divide-and-conquertechnique. Rotation of the fragments within the capsu-lar bag is easier if all nuclear pieces are in place.Therefore, completely break the nucleus up into asmany pieces as you like before removing any. This maynot be possible if fragments spontaneously dislocateforward, but it is usually achievable. For chop tech-niques, I prefer to break the nucleus into at least six oreight piecesmore if the nucleus is very hard.
Hard cataract. Hard cataracts usually have a tough,sometimes leathery, posterior nuclear plate. The key tosuccessfully breaking the nucleus into small pieces, bywhatever method, is to create some space in the centerof the nucleus. I learned from Abhay R. Vasavada, MS,FRCS, of Ahmedabad, India, to sculpt a small but deepcrater in the center of the lens, allowing the remainingring of nucleus to be chopped or cracked. This maneu-ver is easier when one is using a Kelman angled tipbecause you can reach deep into the nucleus withoutdistorting the cornea and losing your clear view.
Pearls for Cataract Removal
Surgeons offer their advice for soft, medium, and hard cataracts.
BY DAVID ALLEN, FRCS, FRCOPHTH; JOHAN BLANCKAERT, MD; RAJA DATTA, MS;
I. HOWARD FINE, MD; ALESSANDRO FRANCHINI, MD; MIKIO INAMURA, MD;
BJORN JOHANSSON, MD, PHD; RAMN LORENTE MOORE, MD, PHD; SIMONETTA MORSELLI, MD;
ANTONIO TOSO, MD; MILIND V. PANDE, DO, FRCS, FRCOPHTH; ISABEL PRIETO, MD;
MARIE-JOSE TASSIGNON, MD; AND KHIUN F. TJIA, MD
Figure 1. Multiple golden rings after
Figure 2. The small, central nucleus is easily
displaced and then consumed.
JOHAN BLANCKAERT, MDSoft cataract. In most soft cataract cases, the patient is
young and would like to continue leading an active lifestyle. Apremium IOL solution or a multifocal IOL is the best optionfor these active patients. Its obvious that in any cataract caseyou always need to do whatever you can to avoid posteriorcapsule rupture and zonulolysis. These two complications cancompromise IOL centration, an essential component whenimplanting premium IOLs. For this reason, in those softercataracts I frequently opt to do either a phaco roll or nucleusrotation technique, which has been so well described by JoseL. Guell, MD, of Spain. This technique reduces zonular stressand is safe for the posterior capsule. The most importantpearl is achieving a good hydrodissection.
Medium cataract. Patients with medium cataracts aretypically standard cataract patients. My first pearl would be:Do not fall into a routine. Secondly, a good anterior capsu-lorrhexis must be centered on the first Purkinje reflex of thecornea. A 5.5-mm capsulorrhexis is the best choice in thesepatients because it is large enough to avoid anterior capsulecontraction and small enough to provide an overlap of theIOL optic. If posterior capsule rupture forces you to use asulcus-fixated IOL, then optic capture can still be done withexcellent IOL centration.
Hard cataract. Avoiding corneal burn is the most impor-tant point in patients with hard cataracts. I would chooseeither torsional phaco with the Infiniti platform (AlconLaboratories, Inc., Fort Worth, Texas) or the WhitestarSignature Ice platform (Abbott Medical Optics, Inc., SantaAna, California). Both systems are notorious for the coolphaco needle temperature needed in those hard, longcataract emulsifications.
RAJA DATTA, MSSoft cataract. Cracking the nucleus and completely
separating the quadrants is difficult in very softcataracts. The procedure is not made easier by soft lensmaterial and cortical matter that continuously enter theanterior chamber and decrease visibility. To combatthese difficulties, the central two-thirds of the softnucleus should be hydrodelineated after initialhydrodissection. Following separation of the centralnucleus from the thick surrounding epinucleus (Figure3A), it is slowly brought out into the anterior chamber(Figures 3B and C). Depending on its hardness, eitherthis soft central nucleus can be aspirated with thephaco tip (footswitch in position 2), keeping the vacu-um at no more than 150 mm Hg and aspiration flowrate (AFR) no more than 30 cc/minute, or a little phacoenergy may be used (Figure 3D).
The thick epinucleus can be aspirated with the phaco tipusing a maximum vacuum of 100 mm Hg and AFR of 25
cc/minute. Alternatively, you may use a coaxial I/A tip. Thismethod is easier and takes little time, especially in youngpatients (up to 50 years of age) or those with posterior sub-capsular, central, or very early nuclear cataracts.
Medium cataract. These cataracts are the easiest to tack-le. During sculpting of these nuclei, it is not necessary to goas deep as you do with very hard ones. Sculpting up to two-thirds of the total depth of the nucleus will crack it com-pletely. Going deeper may often lead to passage into the vit-reous cavity because the resistance of the central nucleus ismuch less than in harder cataracts.
While one is removing the last piece of nucleus, the vacu-
2 I CATARACT & REFRACTIVE SURGERY TODAY EUROPE I MAY 2009
Figure 3. (A) Hydrodelineation of the central nucleus. (B) The
nucleus core is brought into the anterior chamber. (C) The
nucleus core in the anterior chamber. (D) The nucleus is
phacoemulsified in the anterior chamber.
Figure 4. (A) Deep Sculpting of a hard cataract. (B) The two
instruments used for cracking are kept together in the deep-
est part of the groove. (C) Achieving complete division of the
nucleur fragments. (D) Separating the intranuclear fibers.
um should be between 100 and 150 mm Hg and AFRbetween 25 and 30 cc/minute. The reason for these settingsis not because of the jumping fragments that may hit andrupture the posterior capsule, but in case of accidental occlu-sion of the phaco tip with posterior cortical matter and theposterior capsule, which can cause a rent. With these param-eters set low in the event of accidental occlusion, you canimmediately switch to footswitch position 1, which shouldrelease the posterior capsule without causing damage.
Hard cataract. Cracking the nucleus in the two extremesof nuclear hardness (ie, very soft and very hard) is a difficulttask. Hard to very hard cataracts, especially those that areamber or black in color, are the most difficult to crack. Inthese cases, it is advisable to adopt the four-quadrant orstop-and-chop method.
Sculpting should be done deeply, until the posteriornuclear plate is reached (Figure 4A). The two instrumentsused to crack the nucleus are placed so that the tips toucheach other as well as the floor of the groove (Figure 4B). Thetips are then slowly separated to create a crack in the nucle-us that should start from the periphery, under full visibility,and gradually move toward the center. Care must be takento ensure complete separation of the nuclear fragments,including the posterior nuclear plate (Figure 4C).
Difficulty arises in these cases due to the resilient intranu-clear fibers, which are tenacious and difficult to separate. It isalways advisable to break these fibers by separating the frag-ments at their site of origin (Figure 4D).
Utmost care must be taken while separating thenuclear fragments to achieve a complete crack, whichshould extend throughout the depth of the nucleus.Since these nuclei are not only hard and leathery butalso extra large in size, they occupy almost the whole ofthe capsular bag, which is distended, with little or nocortical matter separating them.
Care must also be taken while creating the crack. Pullingthe pieces away from each other to crack the nucleus trans-mits pressure directly to the capsular bag. The more dis-tance between pieces, especially at the periphery, the morethe stretch force on the already distended capsular bag,which may lead to a capsular tear. Therefore, it is imperativeto start cracking at the periphery and go slowly down to thecenter of the nucleus.
I. HOWARD FINE, MDSoft cataract. For soft nuclei, I hydroexpress the lens
into the capsulorrhexis plane and carousel it with thebevel of the phaco tip pointed toward the lens equator.I place the second instrument above