management of the subluxated crystalline lens of... · luxation may occur from congenital or...

REVIEW/UPDATE

Management of the sub
luxated crystalline lensRichard S. Hoffman, MD, Michael E. Snyder, MD, Uday Devgan, MD, Quentin B. Allen, MD,
Ronald Yeoh, MD, Rosa Braga-Mele, MD, for the ASCRS Cataract Clinical Committee,Challenging/Complicated Cataract Surgery Subcommittee

SubmittFinal revAccepte

Corresp& SimsUSA. E-

Q

P

1904

ed: Maision sd: July

onding, LLC,mail: rs

2013 A

ublished

The surgical management of ectopia lentis presents the ophthalmic surgeon with numerouschallenges and options. From the clinical evaluation to the surgical approach, ectopia lentispatients require additional methodologies, techniques, and devices to ensure the best possibleoutcome. The continued refinement of surgical techniques and adjunctive prosthetic deviceshas led to incremental improvements in the ability to achieve successful in-the-bag placementand centration of intraocular lenses while reducing complications. A thorough understandingof the challenges inherent in ectopia lentis cases and the management of intraoperative compli-cations will ensure that surgeons approaching the correction of these eyes will achieve the bestpossible surgical results.

Financial Disclosure: No author has a financial or proprietary interest in any material or methodmentioned.

J Cataract Refract Surg 2013; 39:1904–1915 Q 2013 ASCRS and ESCRS

The surgical management of ectopia lentis is one of themore challenging situations an anterior segmentsurgeon may encounter. Ectopia lentis encompassesany displacement or malposition of the crystallinelens irrespective of the cause or association. Lens sub-luxation may occur from congenital or developmentalconditions such asMarfan syndrome, homocystinuria,Ehlers-Danlos syndrome, hyperlysinemia, sulfite oxi-dase deficiency, simple primary ectopia lentis, andcongenital aniridia syndrome among others.1,2 Sub-luxation may also be acquired due to blunt externaltrauma or iatrogenic zonular dehiscence inducedduring complicated cataract surgery. Perhaps themost common cause for adult-onset zonular weaknessis that which occurs in pseudoexfoliation syndrome(PXF), in which progressive zonular degradation canresult in phacodonesis and crystalline lens subluxa-tion, in addition to late postsurgical pseudophacodo-nesis and intraocular lens (IOL) dislocation.3–5

Retinitis pigmentosa can result in a similar progressivezonulopathy.

y 13, 2013.ubmitted: July 14, 2013.18, 2013.

author: Richard S. Hoffman, MD, Drs. Fine, Hoffman1550 Oak Street, Suite 5, Eugene, Oregon 97401,[email protected].

SCRS and ESCRS

by Elsevier Inc.

Historically, when intracapsular cataract extractionwas the preferred approach to both routine cataractsurgery and surgical repair of the malpositionedcrystalline lens, the technique for lens extraction wasthe same for all but themost severely dislocated lenses.However, with the advent of extracapsular cataractextraction and IOLs, techniques and approaches forectopia lentis that are distinct and different from thetypical routine cataract extraction have evolved. Theability to manage the patient with preexisting zonularweakness or lens subluxation, as well as the patientwith unexpected intraoperative zonular compromise,has become an important part of the cataract surgeon'sknowledge. The goals of this paper are to review theclinical evaluation of these patients and tosummarize various techniques, devices, and metho-dologies that are relevant to the current surgicalmanagement of ectopia lentis.

CLINICAL EVALUATION

The clinical evaluation of the ectopia lentis patientbegins with an appropriate history, which shouldinclude family history, relevant trauma, and onsetand types of visual symptoms. Some metabolic andgenetic conditions are associated with ectopia lentisand may run in families with different types of inher-itance patterns. Because certain genetic syndromes,such as Marfan syndrome, are associated with signifi-cant systemic medical problems involving other bodysystems, such as the cardiovascular system, a referral

0886-3350/$ - see front matter

http://dx.doi.org/10.1016/j.jcrs.2013.09.005

mailto:[email protected]

http://dx.doi.org/10.1016/j.jcrs.2013.09.005

Figure 1. Mild, moderate, and severe crystal-line lens subluxation.

1905REVIEW/UPDATE: MANAGEMENT OF SUBLUXATED CRYSTALLINE LENS

to a primary care physician for a full systemic andmetabolic workup is recommended.

The symptoms may include moderately blurredvision from induced lenticular astigmatism when thecrystalline lens decenters to a severe decrease in visionif the crystalline lens is subluxated out of the visualaxis. Because trauma is a frequent cause of ectopialentis, patients should be questioned about a historyof ocular trauma. Patient age may lead the ophthal-mologist to suspect different diagnoses; pediatricpatients with ectopia lentis are more likely to sufferfrom metabolic syndromes, whereas adult patientsare more likely to present with Marfan syndrome.

Ophthalmic Examination

Figure 2. Flattened subluxated lens edge suggestive of healthyadjacent lens zonular fibers.

The ophthalmic examination should be comprehen-sive and assess the anterior and posterior segments.The degree of lens dislocation can be classified into3 broad groups (Figure 1): (1) Minimal to mild lenssubluxation in which the lens edge uncovers 0% to25% of the dilated pupil; (2) moderate lens subluxationin which the lens edge uncovers 25% to 50% of thedilated pupil; (3) and severe lens subluxation in whichthe lens edge uncovers greater than 50% of the pupil.

The degree of zonular loss can be localized or exten-sive depending on the condition. Whereas conditionssuch as focal trauma or congenital defects may pro-duce localized zonular compromise, systemic condi-tions such as Marfan syndrome or ocular conditionssuch as PXF can cause global weakness to the zonularfibers. The zonular status will determine the degree ofphacodonesis that can be seen at the slitlamp duringexamination. The zonular fibers may be stretched orabsent, and evaluation of the subluxated lens edge todetermine whether it is round or flattened may indi-cate the status of the remaining fibers. Generally, ifthe lens edge is flat, the remaining zonular fibersshould be fairly healthy and strong (Figure 2). If theedge of the lens remains very round in an area ofabsent or stretched zonular fibers, which is oftena sign that the adjacent intact fibers may not have

J CATARACT REFRACT SURG - V

sufficient strength, the surgeon may be wise to selectcapsule retractors to augment structural support.

Comparing the position of the crystalline lens withthe patient seated at the slitlamp and in the supineposition can also help detect the degree of zonularcompromise and is important in planning the surgicalapproach. In patients without zonular issues, thereshould be no change in the crystalline lens positionwith a change in head position. With zonular compro-mise, a deepening of the anterior chamber with poste-rior dislocation of the crystalline lens is seen when thepatient is placed in the supine position. Rarely, lensesmay appear approachable with the patient in an up-right position but subluxate into a position bettermanaged with a pars plana lensectomy when thepatient is placed supine; thus, the importance of

OL 39, DECEMBER 2013

1906 REVIEW/UPDATE: MANAGEMENT OF SUBLUXATED CRYSTALLINE LENS

both an upright and a supine evaluation. If available,ultrasonic biomicroscopy (UBM) is a valuable tool inassessing the degree of zonular compromise. Sincethe UBM images are recorded with the patient in thesupine position, information gathered will simulatethe condition of the crystalline lens during the surgicalprocedure.

Particularly in cases of trauma, the lens capsuleshould be carefully examined for evidence of damageor puncture. Focal areas of lens capsule damage canpose additional challenges during planned cataractsurgery.

Increased lens density can make cataract surgerymore challenging, as can the presence of vitreousin the anterior chamber. When vitreous prolapsesforward around the area of zonular loss, it may tempo-rarily stabilize the crystalline lens. During cataract sur-gery, a partial vitrectomy will be necessary to addressthis prolapse.

Increased intraocular pressure may be seen in casesin which vitreous occludes the angle of the eye, in PXF,or when previous trauma that ruptured zonular fibersalso caused angle trauma and recession. Similarly,prior inflammation, trauma, and vitreous prolapsecan lead to corneal compromise and if that is sus-pected, an endothelial cell count should be performed.

Finally, the posterior segment of the eye should becarefully examined. Any evidence of retinal tears,breaks, or tufts should be sent for retinal consultationand treatment prior to performing the elective cataractsurgery.

SURGICAL APPROACH

Planning

The surgical approach to phacoemulsification of thesubluxated crystalline lens differs depending on thedegree of zonulopathy and the underlying pathophys-iologic origin. In cases in which the zonular abnormal-ity is less than 3 contiguous clock hours, attentivesurgical technique may suffice for a successful surgicaloutcome, although capsule retractors may provideadditional support. If a posttraumatic eye has a smallfocal area of dialysis with an otherwise strong adjacentzonular apparatus, a capsular tension ring (CTR) maynot be required. In cases of even mild zonular laxitybut with a progressive pathologic state such as PXF,Weil-Marchesani, Marfan syndrome, sulfite oxidasedeficiency, retinitis pigmentosa, or the like, the zonu-lar problems can be expected to worsen over timeand a CTR should be placed, if only to facilitatepossible future refixation. In a young patient withsuch progressive diseases, a sutured CTR with scleralfixation might be prudent from the outset, even in theabsence of lens displacement, although this would be


up to the judgment of the individual surgeon. Therelative degree of zonulopathy may not be readilyapparent at the beginning of a case. Thus, surgeonswho choose to tackle these cases should be preparedfor greater damage than is readily apparent at theoutset of the procedure.

Capsulorhexis

A complete capsulorhexis is paramount to success-ful phacoemulsification and bag preservation in anyectopia lentis case. The capsulorhexis in these eyes ismore challenging than in a standard case becausespecial considerations are required for the initiationand completion. First, puncturing the anterior capsuleis not always easy when zonular counter tractionis compromised and in young eyes in which the lenscapsule is highly elastic. The use of trypan-blue dyereduces the elasticity of the capsule and makes pene-tration of the bag and propagation of the capsulorhexiseasier, especially in young eyes.6 The blue staining alsoaids in visualization, which may be hampered in theseeyes despite limited nuclear sclerosis, and in avoidingunintended capsulorhexis contact and compromiseduring the case.

The lack of an anteroposterior barrier in zonulop-athy cases can lead to a loss of the red reflex followingsimple irrigation of trypan blue into the anterior cham-ber. For this reason, it is safer to paint a few drops ofthe dye directly across the anterior capsule in anophthalmic viscosurgical device (OVD)-filled anteriorchamber. The capsule can be penetrated with a stan-dard cystotome, a microvitreoretinal blade, or astraight 25-gauge needle. If the capsule does notpenetrate easily, the crossed-swords capsule pinch7

approach using 2 opposing 30-gauge needle tips canbe used to pierce the capsule and create a starting pointfor the capsulorhexis (Figure 3). In the most unstablelenses, a microforceps or hook may be needed tosteady the lens during the continuous tear.

The capsulorhexis should be centered on the crystal-line lens, not on the pupil or the corneal apex. In thecase of a misshapen lens, the shape of the capsulo-rhexis should follow the outer contour of the lens,whether oval, round, or kidney-bean shaped. The cap-sulorhexis size should take into consideration the needfor at least a 2.0mmmargin between the capsulorhexisedge and the equator, since a generous anterior leafletis necessary to keep the CTR in the bag when it is un-der tension. This is particularly crucial when anAhmed segmentA is used since the segment's suturecreates a rotational moment arm of force anteriorlyaround the bag equator at its axis. Execution of thecapsulorhexis is often most facile when the tear startsin a direction pulling away from the area of greatest


Figure 3. Crossed-swords capsule-pinch technique for initiatingcapsulotomy in the presence of a weak zonule.

Figure 4. Initiating capsulorhexis in the direction of weak zonularfibers using healthy zonular fibers for counter traction.


zonular counter traction toward the weakened zonu-lar fibers (Figure 4). Microincision forceps can beextremely useful in accessing the capsule fromdifferent paracentesis microincisions as this processadvances around the circumference. In addition, theseforceps are less likely to result in loss of OVD from theanterior chamber, which can develop with a standardcapsulorhexis forceps through the relatively largemain incision. This loss of OVD can result in progres-sive anterior chamber shallowing and incrementalanterior lens movement that can complicate comple-tion of the capsulorhexis.

Femtosecond laser–assisted cataract surgery in-creased in 2012 and 2013 and may offer advantagesin complex cataracts such as traumatic cataracts8

and less severe cases of subluxated cataracts. Thefemtosecond laser does not depend on counter resis-tance from zonular support and is able to cut a circu-lar anterior capsule opening despite subluxation ofthe lens as long as the lens is not tilted excessively af-ter docking with the patient interface. A furtherbenefit of femtosecond laser–assisted cataract sur-gery is the creation of gas bubbles in and aroundthe nucleus during nuclear femtosecond fragmenta-tion, leading to pneumodissection, which facilitatesgentle nuclear rotation with little or no hydrodissec-tion. Not every subluxated crystalline lens lends itselfto this type of surgery; some lenses are too grosslysubluxated, some may have poorly dilating pupils,and some may have a mobile crystalline lens. These


represent contraindications to successful femto-second laser–assisted phaco surgery. The ideal caseis the patient with PXF or traumatic cataract in whichmild phacodonesis is noted and in whom the cataractis primarily in the anatomical position.

Stabilization of the Capsular Bag

In cases of moderate zonular loss or dysfunction inthe 3-to-6 clock hour range, some form of augmentedcapsule support will likely be needed. Flexible irisretractors placed through limbal stab incisions canbe used to hook the capsulorhexis edge and supportthe bag.9 These work reasonably well, although thereis a small chance that the hook may inadvertentlytear the capsulorhexis margin. Capsule hooks, incontrast, support the bag by its equator, not thecapsule margin, thereby keeping the bag distendedand also reducing the likelihood of aspiration ofthe bag equator as the lens material is evacuated.B

In either case, when tightening the hooks, enoughtension is placed to stabilize the bag, but efforts tocompletely recenter the bag by hook alone shouldnot be made at this time as they may compromisethe opposing healthy zonular fibers or place unduestress on the capsulorhexis during phacoemulsi-fication. In addition, when using hooks as countertraction during capsulorhexis creation, the hooksshould be placed at least 2 to 3 clock hours fromthe leading edge of the capsulorhexis to avoid


Figure 5. Inadvertent capsulorhexis tear toward the lens equatordue to a capsule hook being placed too close to the capsulorhexisedge with excessive tension.

Figure 6. Iris hook placed through an Ahmed tension ring segmenteyelet to support the bag equator.


tractional forces that will cause the leading edgeto extend peripherally toward the bag equator(Figure 5).

A further option to stabilize the bag during phaco-emulsification would be placement of an Ahmedsegment. When the segment is used early in a case,OVD is placed under the anterior capsule leaflet andthe cortex is pushed back, up to the equator in thequadrant of interest. The segment is then slippedinto the bag fornix, leaving the fixation element ante-rior to the capsulorhexis. Unlike its use when the baghas been evacuated, when the segment is used beforephaco, no suture is placed and the segment is stabi-lized by placing a flexible iris retractor through thelimbus, pointing the hook's fixation end upward,then engaging it through the Ahmed segment fixationeyelet and tightening to stabilize the bag (Figure 6). Forsurgeons outside the United States, the Assi Anchor10

and Yaguchi hook11 are other viable options that aresmaller in profile and may be easier to insert.

When the zonular dialysis is severe, for examplemore than 6 clock hours, some sort of bag stabilizationwith hooks, retractors, or segments for phaco is nearlymandatory for safe evacuation of the capsular bag,except perhaps in very young patients in whom thebag can be evacuated by simple aspiration, sometimeseven dry aspiration using a 27-gauge cannula in anOVD-filled anterior segment. Some surgeons mayprefer to place a CTR early in the procedure.12–14,C

This approach maintains an expanded capsular bag,supports the zonular apparatus, and may facilitate


phacoemulsification. However, placing the CTR(either standard or fixated) early can be much morechallenging because the lens within the bag mayimpede the CTR progression and may strip zonularfibers.14,15 Furthermore, the CTR may trap corticalmaterial in the equator, making subsequent removaldifficult or impossible. One dictum that is followedby many surgeons is to place the CTR “as late as youcan, but as soon as you must.”D

Phacoemulsification of the Loose Lens

With a stabilized bag and pressurized OVD-filledanterior segment, the next step is evacuation of thecataractous (or misshapen) lens. Hydrodissectionand viscodissection are critical tools inmanaging looselens cases and should be performed in all eyes, some-times repeatedly. In the presence of zonulopathy, withan absence of counter traction to mobilize the lensnucleus, inadequate hydrodissection or viscodissec-tion may endanger the remaining zonular fibers andeven the bag itself.

The youngest lenses can be aspirated with irri-gation/aspiration (I/A) handpieces or a cannula. A27-gauge cannula affords a tremendous degree ofsafety and control. If vitreous is contacted, it can bereadily refluxed with minimal retinal traction. Use ofautomated equipment requires vigilant attentiveness.Replenishing dispersive OVD volume into thecapsular fornix throughout the case maintains baganatomy as lens material is evacuated and increases


Figure 7. Tangential aspiration of cortical material toward areas ofzonular weakness.

Figure 8. Injection of Cionni CTR using an injector.


safety. Periodic augmentation of a dispersive OVDplug over the exposed hyaloid face will also reducethe risk for vitreous prolapse during the procedureand diminish the chances of a nuclear fragmentmigrating posteriorly.

Phacoemulsification within the capsular bag re-duces the likelihood of errant fragments finding theposterior segment but, concomitantly, increases theodds of inadvertent bag or zonule damage by the pha-co or I/A handpiece manipulations. In contrast, it iseasier to emulsify the lenswithin the anterior chamber,but turbulence is higher and control of fragments islower. The soft lens can usually be easily prolapsedanteriorly and because of its sticky nature is unlikelyto fall into the vitreous cavity. The denser nuclei areusually hard to get out of the bag and have a greaterchance of dislocating. Accordingly, sometimes thelens will dictate what it “wants” to do and the surgeonwill follow suit. Lower aspiration and flow parame-ters, whether limited by the machine panel or by thesurgeon's judicious use of the foot pedal, will reduceturbulence, maintaining greater control over frag-ments of the lens between liberation from the bagand aspiration by the phaco needle.

Cortical aspiration, achieved by an automated coax-ial device, bimanual aspiration, or manual dry aspira-tion should limit stress to the remaining zonular fibers.Stripping from the capsulorhexis margin towardthe periphery minimizes strain, while centripetalmaneuvers maximize tension. Tangential stripping is


intermediate and is very useful in meridians distantfrom the dehiscence but should be used with cautiousdirect observation in areas adjacent to the break toprevent “unzipping” of intact zonular fibers at a dehis-cence edge. Tangential stripping should always beperformed toward the area of missing or weak zonularfibers to limit stress on the adjacent fibers (Figure 7).While complete cortical removal is a noble and appro-priate goal, excessive efforts to remove small strandsshould not risk capsular or zonular damage.

Capsular Tension Ring Selection

Deciding which CTR to use depends on the degreeof and likelihood for progression of damage. Whenthe dialysis is small, a standard CTR is usuallyadequate. A standard CTR can be placed by injectoror manual insertion and should be inserted to directthe vector forces toward the area of greatest zonularweakness. If there is more than 4 clock hours of dam-age or if the lens is moderately to severely displaced, afixation device is required. One option for fixation in-volves the use of a standard CTR and a ring segment incombination. This disassembled fixation ring offersthe advantage of simple insertion of the CTR and fixa-tion element with less zonular stress than would beproduced with insertion of a Cionni CTR.16 If thecapsular rim is less generous than anticipated with alarger than planned capsulorhexis, a Cionni CTR is asuperior option to a ring segment. In settings in which


Figure 9. Microforceps insertion of Ahmed ring segment.


cost is a consideration, the total cost of a standard CTRand separate ring segment may also be higher than aCionni CTR alone. When using a Cionni CTR, thesmallest (1-G) version is most facile for all but thelargest capsular bags.

Long-Term Fixation

Ultimately, when the crystalline lens has beenremoved, some mechanism of suture fixation forlong-term stability is needed in any case with morethan 4 clock hours of involvement. Obviously, thehooks and retractors used during the procedurecannot serve this purpose. Long-term stability can beachieved using a Cionni-style CTR (Figure 8), anAhmed segment (Figure 9), an Assi Anchor, or in casesof severe weakness or progressive disease in youngerpatients, any combination of those devices. Thedouble-fixated Cionni CTR is somewhat cumbersometo place, and with the advent of the Ahmed segment,most find it more facile to place 1 Cionni CTR and


1 segment or 2 segments and a standard CTR. Somesurgeons try to preserve the capsular bag wheneverpossible, even with heroic measures, while othersmay prefer direct suture fixation of the IOL to the irisor ciliary sulcus.

Placement of Cionni CTRs in the bag should beperformed in a clockwise direction. Preloading theleading eyelet with a 10-0 nylon suture makes place-ment around the first few clock hours much easier,adding tension to the leading suture to reduce thearc of curvature and prevent the device from hangingup on the capsular fornix (Figure 10). A microforcepsgrasping the nylon can also lead the element into thebag like a leash. A fixation suture through the fixationelement eyelet should similarly be preloaded.

An Ahmed segment can be placed directly into thebag fornix in the desired clock hour. In any case, thefixation element should course anteriorly aroundthe capsulorhexis margin. When a polytetrafluoro-ethylene (Gore-Tex) suture is used, the white suturewill appear blue under a trypan blue–stained capsule,indicating that the element remains under the ante-rior capsule and in the bag, a definite sign of a needfor repositioning that element. Once a segment hasbeen effectively placed within the capsular bag, thefixation element is rotated to the area of greatestweakness. Some surgeons prefer ab interno place-ment of the sutures through the scleral wall, whileothers prefer to create an exterior opening in thesclera, place the blunt end of the fixation suture intothe anterior chamber, and retrieve the suture with amicroforceps placed ab externo through the scleralwall.

Once both sutures are externalized, a throw can beplaced and the IOL placed in the capsular bag. Withthe globe pressurized, suture tension should betitrated to achieve maximal IOL centration. Lockingthrows can then be placed and the knot secured.Whether the sutures are tied under a corneoscleralpocket, tied under a scleral flap, or tied over episclerais a matter of surgeon preference, as no techniquehas been definitively proven superior over the

Figure 10.Microforceps grasping a preloaded10-0 nylon through the leading eyelet toreduce the arc of curvature of a Cionni CTR,preventing bag equator stress.



others. However, there is a general consensus thatexposed subconjunctival knots should be avoidedto prevent overlying conjunctival erosion and subse-quent endophthalmitis.

Suture Material

Suture material should be permanent. Polypro-pylene 10-0 is unadvisable, as it will hydrolyze overtimewith a roughly 5- to 10-year survival time.17 Poly-propylene 9-0 should have a longer survival time;however, to date, the interval before degradation ofthis suture gauge has not been reported. A polytetra-fluoroethylene CV-8 suture has been used for scleralfixation off label and to date has had excellentlongevity.

In cases with externally tied knots, rotation ofthe knot through 1 scleral opening into the eye wallis recommended and can be performed while holdingthe fixation eyelet of the ring/segmentwith a 23-gaugemicroforceps to avoid decentration of the capsular bagin the process. When this cannot be achieved, a patchgraft is advisable.

While many options of patch material exist, costsand access can vary regionally. Split thickness corneahas the least likelihood ofmelt over time, does not altercosmesis, and is reasonably easy toworkwith. Pericar-dial patch material is very easy to suture and can bemore readily fashioned to different shapes than donorsclera, although its color is different than sclera andmay be cosmetically unappealing in an obviouslocation.

Intraocular Lens Selection

Selection of the appropriate IOL in cases of ectopialentis will often depend on successful completion ofan intact capsulorhexis, uncomplicated lens extraction,and adequate bag fixation. If an intact, properlyfixated and centered capsular bag is accomplished,and a circumferential CTR is in place (in the form ofa standard CTR or Cionni-style CTR), a 1-piece or3-piece IOL would be an appropriate IOL forinsertion. Accommodating IOLs should probably beavoided because of the limitedmechanical functioningthat should develop from a fixated capsular bag.

A question that frequently arises surrounds the useof toric and multifocal IOLs. Although both have beenused successfully in ectopia lentis cases, the inherentpathology of the zonular apparatus suggests that theseIOLs should be used in only the most ideal cases. ToricIOLs require proper alignment along the steep cornealmeridian and will lose their astigmatic correction withrotation away from this meridian. The inability toguarantee centration and proper alignment in additionto the possibility of late suture breakage or progressive


zonular degradation requiring late lens-in-the-bagfixation (with possible IOL rotation) suggests that abetter alternative for astigmatic correction in many ofthese patients would be limbal relaxing incisions orlaser corneal refractive surgery.

Multifocal IOLs present the same challenges ofadequate centration and successful determination ofthe effective lens position. The use of multifocal IOLsis most beneficial in young children with ectopia lentisbecause of their loss of phakic accommodation, yet theeyes of these children may be the most likely to havelate complications due to suture degradation andbreakage requiring refixation and proper centrationof the capsular bag. For this reason, it is recommendedthat fixation sutures for these eyes be composed of8-0 polytetrafluoroethylene (off label) rather than9-0 polypropylene when a multifocal IOL is beingconsidered. Regardless of the patient's age, multifocalIOLs should be used in only the most experiencedhands with appropriate informed consent and onlyif proper centration can be guaranteed during thesurgery.

INTRAOPERATIVE COMPLICATION MANAGEMENT

Vitreous Management

Loose lens cases often have vitreous in the anteriorchamber at the outset of the case and are more vulner-able to vitreous loss during the procedure. An absoluterule in these cases is to avoid vitreous traction. If vitre-ous is present at the beginning of the case, it must beremoved from the anterior chamber before anteriorsegment maneuvers begin. Staining the vitreous withtriamcinolone can improve visualization.18 Anotheroption to aid in visualization is the use of an illumi-nator probe that includes irrigation. In rare cases ofminimal prolapse, the vitreous can be sequestered orpushed back by the use of a dispersive OVD. In mostcases of prolapse, a limited vitrectomy is required. Asingle-port pars plana approach has the least likeli-hood of damaging remaining zonular fibers or thecapsule during the removal process. Once the pro-lapsed vitreous has been removed, placing a disper-sive OVD over the exposed region should limitadditional prolapse during the case. If vitreous doespresent again, the surgeon must stabilize the anteriorchamber with OVD, halt maneuvers, and perform anadditional vitrectomy.

Capsular Bag Compromise

Perhaps the most challenging and essential step inectopia lentis procedures is completion of an intactanterior capsulorhexis. If the capsulorhexis starts toextend to the bag equator, attempts to redirect the


Figure 11. Iris-fixated PC IOL. Figure 12. Iris-imbricated AC IOL.


edge centrally must be made. Capsule-supportinghooks placed too close to the capsulorhexis edgemay inadvertently place force on the leading edgethat causes outward movement of the tear. Looseningthese hooks and placing additional OVD to deepen theanterior chamber may aid in redirecting the capsulo-rhexis centrally. If the edge is not salvageable, microin-cision intraocular scissors can be used to start a newcapsulorhexis by incising the capsule perpendicularto the peripheral tear and then continuing the capsulo-rhexis from this new starting point. The capsulorhexiscan also be completed by using the scissors to create aflap at the original starting point, cutting tangentiallyto create a smooth edge from this new starting point.Tearing this new flap in a direction opposite the initialdirection will allow the capsulorhexis to be completedto the region of the peripheral tear. In the presence of acompromised anterior capsulorhexis, a CTR shouldnot be used. However, an Ahmed segment can beused in this scenario as long as the region of compro-mised anterior capsule is more than 3 clock hoursaway from the ultimate fixation site of the ringsegment.

In the presence of posterior capsule compromise, noCTRs should be placed and attempts to place ring seg-ments should probably be avoided except in the mostideal situations. A posterior capsule tear will usuallynecessitate an alternative approach for IOL insertion,outside the capsular bag.

Intraocular Lens Placement

When a compromised capsular bag is encountered,there are many alternatives for IOL placement outsidethe bag. Intraocular lenses should not be placed in thesulcus without some type of fixation because of thelikelihood of the IOL haptics migrating through


stretched zonular fibers or a frank zonular dialysis,resulting in subluxation of the posterior chamberIOL (PC IOL). Scleral fixation can be accomplishedwith 9-0 polypropylene or 8-0 polytetrafluoroethyleneusing any technique that avoids exposure of sub-conjunctival knots. One alternative to the use ofsutures is to fixate the PC IOL by intrascleral hapticcapture.19,20

Perhaps the easiest method for fixating a PC IOL inectopia lentis eyes uses iris fixation of the haptics with10-0 or 9-0 polypropylene. The presence of the capsule,although compromised, allows easy insertion of theIOL into the sulcus, followed by prolapse of the opticabove the pupillary plane, constriction of the pupilwith a miotic, and iris fixation using a Siepser slipknottechnique (Figure 11).21

If the surgeon is not trained to do complex IOLfixation surgery, other options include asking the pa-tient to wear an aphakic contact lens or implanting ananterior chamber IOL (AC IOL). An AC IOL maypose a risk to the corneal endothelium if not properlysized, resulting in long-term corneal decompensa-tion. For this reason, it may be desirable to avoidAC IOLs in patients whose life expectancy is greaterthan 20 years. Many of these eyes may have relativelyenlarged axial lengths or anterior chambers, andan interesting alternative to the Kelman-style angle-fixated AC IOL is an iris-imbricated Worst-styleIOL in which the haptics are imbricated on the irissurface and not dependent on the angle for fixation(Figure 12).

A review by the American Academy of Ophthal-mology22 found no significant advantage in any ofthe above techniques in the absence of randomcontrolled trials. Thus, the choice of technique andIOL is dependent on the surgeon's training andexperience.


Figure 13. Subluxated capsular bag with CTR and PC IOL withamputated haptic resulting in functional centration of the lens(photo courtesy of Marcelo Ventura, MD).

Figure 14. Anterior chamber IOL in severely subluxated phakiccrystalline lens.


INNOVATIVE APPROACHES

The techniques for treating ectopia lentis evolve asnew adjunctive devices for facilitating the surgeryare invented and become available for use and as new-er innovative techniques are tried and studied.Although capsule bag fixation using prosthetic de-vices may be considered the current state of the artin ectopia lentis patients, other innovative approachesoffer alternatives or possible improvements over cur-rent methods.

One approach used before the advent of modifiedCTRs involved fixation of the anterior lens capsule tothe sclera, where it functioned as a support for a PCIOL and as a vitreous container. With this technique,an incision is made in the anterior lens capsule fromequator to equator, oriented 90 degrees from the me-ridian of subluxation. One-half of the anterior capsuleleaflet that is created is then folded back and sutured tothe sclera using a 10-0 polypropylene suture. Thissutured leaflet provides support for a sclerally posi-tioned or fixated PC IOL, while also acting as a barrierfor vitreous prolapse during aspiration of the lens.23

Another innovativemethod for dealingwith ectopialentis cases was described by Ventura and Endress.24

Rather than attempting to recenter the capsular bagwith scleral fixation, Ventura and Endress decenterthe IOL within the decentered capsular bag to achievea centered optic. After a decentered anterior capsulo-rhexis is created and the lens material is removed, aCTR is placed to support the remaining zonular fibers.One IOL haptic is then amputated from the IOL andthe IOL is inserted into the capsular bag, oriented so


the remaining IOL haptic decenters the IOL optic to-ward the bag equator (Figure 13).

Another approach for dealing with the severely sub-luxated crystalline lens avoids removal of the lens alto-gether. If the patient is optically aphakic due to severelens subluxation, placement of an AC IOL withoutlens extraction simplifies the procedure and avoidsthe potential complications due to vitreous loss orcapsular bag compromise.25 A Kelman-style AC IOLor an iris-fixatedWorst-style aphakic IOL can yield im-mediate visual recovery andmarkedly shortened surgi-cal time (Figure 14). In the rare instances in which thecrystalline lensmay later dislocate into the vitreous cav-ity, the lens can be removed by a pars plana approachby a vitreoretinal surgeon, which might be the safestprocedure in these severely subluxated lenses.

Although modified CTRs have become the state ofthe art for recentering subluxated capsular bags, inser-tion of the complete Cionni-style CTR can be chal-lenging in the presence of moderate to severesubluxations or in the presence of significant zonularweakness. A recent innovation by MalyuginE com-bines the ease of insertion of a traditional CTR with afixation element that allows sclera fixation of theCTR. Wherein a Cionni-style CTR has the fixationelement positioned away from the CTR endpointand elevated above the plane of the CTR, theMalyuginmodification places the fixation element on the end ofthe ring so it can be easily injected into the capsularbag and then manually positioned above the capsulo-rhexis to sclerally fixate the prosthesis (Figure 15). Thisdevice is currently undergoing development and is notavailable in the United States.


Figure 15. Malyugin modified CTR (photo courtesy of BorisMalyugin, MD).


DISCUSSION

The surgical correction for patients with ectopia lentisbegins with a thorough clinical history, extensive clin-ical examination, and appropriate referral to medicalspecialists to evaluate potential metabolic and sys-temic abnormalities. With the advent and develop-ment of current adjunctive surgical devices, most ofthese cases can now be treated with excellent visualand anatomic results, much better than could beaccomplished just a few decades ago. Although thispaper attempts to give a rationalmethod for approach-ing these cases, it in no way suggests there is only onecorrect method of addressing these eyes, nor was itpossible to present all the potential nuances and tech-niques available for remedying ectopia lentis.

Each surgeonwill have his or her own preferences orbiases for when and how to use the various prostheticdevices, which fixation sutures and fixation methodswork best in his or her hands, and which IOLs areappropriate for each clinical presentation. In addition,what is currently believed to be state of the art may inthe future be considered archaic and crude. Thus,each surgeon should keep an open mind as to all alter-native methods of treating ectopia lentis patientswhile making every attempt to be educated about thechallenges and options that are present today.

REFERENCES1. Dureau P. Pathophysiology of zonular diseases. Curr OpinOph-

thalmol 2008; 19:27–30

2. Nelson LB, Maumenee IH. Ectopia lentis. Surv Ophthalmol

1982; 27:143–160


3. Kohnen T. Pseudoexfoliation: impact on cataract surgery and

long-term intraocular lens position [editorial]. J Cataract

Refract Surg 2010; 36:1247–1248

4. Davis D, Brubaker J, Espandar L, Stringham J, Crandall A,

Werner L, Mamalis N. Late-in-the-bag spontaneous intraocular

lens dislocation; evaluation of 86 consecutive cases. Ophthal-

mology 2009; 116:664–670

5. Jehan FS, Mamalis N, Crandall AS. Spontaneous late disloca-

tion of intraocular lens within the capsular bag in pseudoexfolia-

tion patients. Ophthalmology 2001; 108:1727–1731

6. Dick HB, Aliyeva SE, Hengerer F. Effect of trypan blue on the

elasticity of the human anterior lens capsule. J Cataract

Refract Surg 2008; 34:1367–1373

7. Snyder ME, Lindsell LB. Crossed-swords, capsule-pinch tech-

nique for capsulotomy in pediatric and/or loose lens cataract

extraction. J Cataract Refract Surg 2010; 36:197–199

8. Nagy ZZ, Kr�anitz K, Takacs A, Filkorn T, Gergely R, Knorz MC.

Intraocular femtosecond laser use in traumatic cataracts following

penetrating and blunt trauma. J Refract Surg 2012; 28:151–153

9. Chang DF. Phacoemulsification in high-risk cases. In:

Wallace RB III, ed, Refractive Cataract Surgery and Multifocal

IOLs. Thorofare, NJ, Slack, 2001; 121–136

10. Assia EI, Ton Y, Michaeli A. Capsule anchor to manage sublux-

ated lenses: initial clinical experience. J Cataract Refract Surg

2009; 35:1372–1379

11. Yaguchi S, Yaguchi S, Asano Y, Kozawa T, Miyawaki T,

Negishi K, Tsubota K. Repositioning and scleral fixation of sub-

luxated lenses using a T-shaped capsule stabilization hook.

J Cataract Refract Surg 2011; 37:1386–1393

12. BlecherMH, KirkMR. Surgical strategies for themanagement of

zonular compromise. Curr Opin Ophthalmol 2008; 19:31–33

13. Bayraktar S, Altan T, K€uc‚ €uks€umer Y, Yılmaz €OF. Capsular ten-

sion ring implantation after capsulorhexis in phacoemulsification

of cataracts associated with pseudoexfoliation syndrome; intra-

operative complications and early postoperative findings.


14. Ahmed II, Cionni RJ, KranemannC, Crandall AS. Optimal timing

of capsular tension ring implantation: Miyake-Apple video anal-

ysis. J Cataract Refract Surg 2005; 31:1809–1813

15. Dietlein TS, Jacobi PC, KonenW, Krieglstein GK. Complications

of endocapsular tension ring implantation in a child withMarfan’s

syndrome. J Cataract Refract Surg 2000; 26:937–940

16. Cionni RJ, Osher RH. Management of profound zonular dialysis

or weakness with a new endocapsular ring designed for scleral

fixation. J Cataract Refract Surg 1998; 24:1299–1306

17. Price MO, Price FW Jr, Werner L, Berlie C, Mamalis N. Late

dislocation of scleral-sutured posterior chamber intraocular

lenses. J Cataract Refract Surg 2005; 31:1320–1326

18. Burk SE, Da Mata AP, Snyder ME, Schneider S, Osher RH,

Cionni RJ. Visualizing vitreous using Kenalog suspension.


19. Gabor SG, Pavlidis MM. Sutureless intrascleral posterior cham-

ber intraocular lens fixation. J Cataract Refract Surg 2007;

33:1851–1854

20. Agarwal A, Kumar DA, Jacob S, Baid C, Agarwal A,

Srinivasan S. Fibrin glue-assisted sutureless posterior chamber

intraocular lens implantation in eyes with deficient posterior cap-

sules. J Cataract Refract Surg 2008; 34:1433–1438

21. Chang DF. Siepser slipknot for McCannel iris-suture fixation of

subluxated intraocular lenses. J Cataract Refract Surg 2004;

30:1170–1176

22. Wagoner MD, Cox TA, Ariyasu RG, Jacobs DS, Karp CL. Intra-

ocular lens implantation in the absence of capsular support; a

report by the AmericanAcademy ofOphthalmology (Ophthalmic

Technology Assessment). Ophthalmology 2003; 110:840–859



23. Cor�et A, Villar-Kuri J, Tokuda Y, Lu LW. Phacoemulsification in

subluxed cataracts. In: Lu LW, Fine IH, eds, Phacoemulsifica-

tion in Difficult and Challenging Cases. New York, NY, Thieme,

1999; 99–110

24. Ventura M, Endriss D. Implantac‚ ~ao de lente intraocular com

uma alc‚ a amputada: proposta para o tratamento cir�urgico da

subluxac‚ ~ao do cristalinoIntraocular lens implantation with one

loop haptic amputated: a new propose to the subluxation

lens surgical treatment. Arq Bras Oftalmol 2010; 73:135–140.

Available at: http://www.scielo.br/pdf/abo/v73n2/v73n2a07.pdf.

Accessed July 31, 2013

25. HoffmanRS, Fine IH, Packer M. Primary anterior chamber intra-

ocular lens for the treatment of severe crystalline lens subluxa-

tion. J Cataract Refract Surg 2009; 35:1821–1825

OTHER CITED MATERIALA. Ahmed IIK, Kranemann C, Crandall AS, “Capsular Hemi-Ring:

Next Step in Effective Management of Profound Zonular Dial-


ysis,” film presented at the ASCRS Symposium on Cataract,

IOL and Refractive Surgery, San Francisco, California, USA,

April 2003

B. Chang DF, “Traumatic Cataract and Mydriasis,” Cataract &

Refract Surgery Today October 2010, pages 69–71. Available

at: http://bmctoday.net/crstoday/pdfs/crst1010_Feature_chang.

pdf. Accessed July 31, 2013

C. OsherRH, “WeakZonules; Identifying theSubtle Signs of Zonular

Damage,”Cataract &RefractiveSurgery TodayApril 2005, pages

55–56. Availableat: http://bmctoday.net/crstoday/2005/04/article.

asp?fZcrst0405_f2_osher.html. Accessed July 31, 2013

D. Rosenthal K, Personal communication, circa 2005

E. Malyugin B, “Managing Zonular Deficiency; Endocapsular De-

vices can Facilitate Cataract Removal in Patients With Weak

or Missing Zonules,” Cataract & Refractive Surgery Today

Europe February 2013, pages 61–65. Available at: http://bmc

today.net/crstodayeurope/pdfs/0213CRSTEuro_cf_Malyugin.

pdf. Accessed July 31, 2013


http://www.scielo.br/pdf/abo/v73n2/v73n2a07.pdf

http://bmctoday.net/crstoday/pdfs/crst1010_Feature_chang.pdf

http://bmctoday.net/crstoday/pdfs/crst1010_Feature_chang.pdf

http://bmctoday.net/crstoday/2005/04/article.asp?f=crst0405_f2_osher.html

http://bmctoday.net/crstoday/2005/04/article.asp?f=crst0405_f2_osher.html

http://bmctoday.net/crstodayeurope/pdfs/0213CRSTEuro_cf_Malyugin.pdf



management of the subluxated crystalline lens of... · luxation may occur from congenital or...

Documents