American Academy of Ophthalmology Web Site: www.aao.org
Spotlight on Cataract Surgery
What would you do? Those attending the popular program were asked to vote on how they would manage various complicated cases. Compare their assessments with the experts’ opinions.
This past October, the eighth Annual Spotlight on Cataract Surgery session at the Academy’s Joint Meeting was entitled Clinical Decision-Making With Cataract Complications: You Make the Call. Cochaired by Bruce Wallace, MD, and myself, this four-hour program was organized around seven video cases that demonstrated a variety of cataract surgical complications.
As I presented the video cases, I would pause at the point of a complication. The attendees were then asked to make clinical decisions using their electronic audience response keypads. This was followed by several rapid-fire didactic presentations on topics of relevance to the case. Next, two panel discussants (who had never viewed the case) were asked to make their own recommendations before the video of the outcome was shown. Following additional audience polling about preferences and practices, the two panelists made their final comments.
In all, nearly 40 presenters and panelists spoke about managing unhappy multifocal IOL patients, cataract with severe uveitis, delayed bag-IOL dislocation, diffuse zonular weakness, posterior capsular rupture with posterior polar cataract, and the rock hard nucleus in a crowded anterior chamber. Robert H. Osher, MD, concluded the symposium by delivering the Academy’s fifth annual Charles Kelman Lecture, entitled Excerpts From My Favorite Videos: An Educational and Entertainment Odyssey. The entire program with videos and PowerPoint was captured on DVD-ROM.
This EyeNet article reports the results of the 32 audience response questions, along with written commentary from the symposium speakers and panelists. Because of the anonymous nature of this polling method, the audience opinions are always interesting and were discussed in real time during the symposium by our panelists.
The Academy’s Annual Meeting now features a daylong, continuous series of cataract events that constitute Cataract Monday. The Spotlight on Cataract Surgery program was followed by the preview of the public television documentary “Through My Eyes: The Charlie Kelman Story.” In the afternoon, the ASCRS-cosponsored symposium on Complications of Premium IOLs was followed by the Around the World in 80 Minutes international symposium on New and Emerging IOL Technologies.
—David F. Chang, MD
Unhappy Multifocal Patient
Q1: For presbyopia-correcting IOL patients, my preoperative evaluation includes:
Steven Dell While it is interesting that 12 percent of the audience incorporates wavefront and topography testing into their preoperative workup of presbyopia-correcting IOL patients, the real issue in my mind is that 10 percent of the audience performs neither test. There is a good argument to be made for omitting the wavefront analysis, but I can’t imagine skipping corneal topography in these patients. In fact, topography has become such an integral part of all IOL surgery for me that I would feel uncomfortable operating without it.
In the context of presbyopia-correcting IOLs, I believe topography is essential. Conditions such as forme fruste keratoconus and pellucid marginal degeneration must be detected before surgery, as they may be a source of reduced visual acuity. These conditions also would dramatically affect both the performance of a multifocal IOL and the patient’s ability to undergo laser vision correction or limbal-relaxing procedures.
Scott MacRae Presbyopia-correcting IOLs, both multifocal and accommodating, may be strongly affected by corneal aberrations, and a preoperative corneal topography is very helpful in evaluating this. For instance, if a patient has even moderate corneal astigmatism, such as 0.75 D, this should be corrected, if possible, to optimize the patient’s vision at distance and near with an IOL. In addition, if a patient has a large degree of vertical coma from previous contact lens wear, this may reduce the likelihood of success with a presbyopic IOL because the aberration will degrade image quality at distance and near.
Although clinicians may not have corneal topographers that provide exact corneal higher-order aberration terms, they can use the topography-irregularity index on the corneal topographer and avoid implanting a presbyopic IOL with a highly irregular cornea. More frequently, corneal topographers are providing information not just on astigmatism but also on higher-order aberrations. I would recommend consulting your topography dealer to see whether such software is available.
Wavefront analysis generally is not as helpful because the wavefront sensor provides a whole eye reading, which includes both the cataractous lens and the cornea. Since the lens often has higher-order aberrations, which will disappear with lens surgery, wavefront analysis is less useful than corneal topography.
Q2: For this unhappy multifocal IOL patient (Fig. 1a, two years after implantation of a ReStor lens) with an open posterior capsule, I would:
Eric Donnenfeld The audience has spoken. Overwhelmingly, they agree with the concept that if we open the posterior capsule, the patient keeps the IOL. Opening the posterior capsule significantly increases the risk of vitreous loss, peripheral capsular tears and decentration of the exchanged IOL. Judging the contribution of the opaque posterior capsule vs. the intrinsic loss of quality of vision with a presbyopic IOL is the most difficult decision we make with every patient who is truly unhappy after presbyopic IOL implantation; for this reason, all other treatment options should be explored before posterior capsulotomy.
I agree with the audience that exchanging an IOL with an open posterior capsule should be strongly discouraged. However, with an appropriate and well-documented informed consent, an IOL exchange in this setting can be considered.
Q3: During IOL exchange with an open posterior capsule, the haptic is trapped (Fig. 1b). Now what?
Mark Packer No doubt the optimal solution is to free the haptic and remove the IOL in toto. However, damaging the zonular apparatus or the capsule is not worth the price. Therefore, one plays a quiet game of desperation, teasing and pulling on the haptic, injecting more dispersive viscoelastic along the path of the haptic and gently rotating the IOL, meanwhile closely watching the capsule for signs stretching up to but not quite to the point of tearing. Inserting a capsular tension ring (CTR) may provide counter traction and an increased margin of safety. In the end, amputation remains the fallback option. As time ticks by, the steadily increasing risk of complications drives the surgeon closer to the scissors. The patient will never know if the haptic is left behind, but irreversible capsular compromise that necessitates sutures or anterior chamber IOL will likely result in a more complex postoperative course.
Q4: With a large zonular dialysis and posterior capsular defect (after removing the multifocal IOL), how would you fixate the replacement monofocal IOL?
Doug Koch Frankly, I am surprised by these results. Although many patients will have a satisfactory outcome with sulcus implantation of an IOL in the presence of a capsular tear and zonular dialysis, there is also a risk of dislocation of the implant. In almost all of these situations, I prefer to suture fix the security IOL with McCannel-type sutures. If the dialysis is less than 3 to 4 clock hours and there appears to be good capsular support in other regions, then sulcus implantation alone without suture would probably be adequate. Obviously, the majority of the attendees disagree!
Q5: Have you had to explant presbyopia-correcting IOLs?
Bonnie Henderson The response to this question reveals several interesting findings. First, the 44 percent who do not use any presbyopia-correcting IOLs accurately reflects the overall rate of usage in the United States as shown in recent market data surveys. The second finding is that many physicians have not had to explant these IOLs—therefore, we can assume that a significant percentage of patients have been satisfied with their outcomes, regardless of the type of IOL used.
The higher percentage of multifocal IOLs being explanted is not surprising, as the most common presbyopia-correcting IOL being implanted currently here and in Europe is the acrylic multifocal IOL. Also, the acrylic multifocal IOL is considerably easier to remove than is the accommodating IOL, which may decrease reluctance to consider removing a multifocal IOL.
As more cataract surgeons begin to implant presbyopia-correcting IOLs and the number of post-LASIK patients with subsequent postoperative refractive surprises increases, the rate of IOL exchanges may also rise.
Cataract and Uveitis
Q6: Which small-pupil technique would you employ in this uveitis patient (Fig. 2)?
Dick Lindstrom It is interesting that 97 percent of the audience felt comfortable managing this complex cataract case. In such cases, a peribulbar block is an option, as extra manipulation will be required. In this patient, following placement of a cohesive viscoelastic, I would start by performing synechialysis with removal of the fibrotic band with a forceps, which is usually present at the pupil margin. It will peel off if grasped with a forceps.
Next, either iris retractors or a Malyugin ring would be appropriate. While most in the audience still favor placement of four iris retractors, I have evolved in most cases to the use of a 7-mm Malyugin ring. I find it quicker and easier to place. One must, however, be very careful during removal, as it is possible to snag the iris with resultant damage. A careful review of the instructions that come with the ring is wise before one’s first case.
These patients usually have more flare and cell postoperatively and may actually present on day one with a fibrin plug in the pupil. I use 1 ml of heparin (1,000 units per ml in the irrigating solution bottle) to reduce this response. This will not increase the risk of bleeding.
I also do not use intracameral miotics in these cases. Subconjunctival—or, for some, intracameral or intravitreal—triamcinolone is worth considering, and I treat these patients with topical steroids and NSAIDs for at least two months.
Tom Oetting I agree with the audience and in this case would use iris retractors. First I would make the main paracentesis. Then I would use a Grieshaber iris hook blade, a 27-gauge needle or a standard paracentesis blade to make the four short and posterior paracenteses for the iris hooks. I would plan on having one hook just under the main wound so that the hooks form the pupil into a diamond configuration relative to the main incision. While placing the hooks I would add no or very little ophthalmic viscoelastic device (OVD). This will make staining the lens capsule easier and will keep the chamber flat, which will ease engagement of the hooks onto the iris. Often the central posterior synechiae will easily lyse simply by placing the hooks.
Sometimes some OVD dissection or a Kuglen hook is needed to start the synechialysis.
After the hooks are in place, I would consider using trypan to stain the capsule under air. Then I would finally add OVD to stiffen the chamber and place the main incision (over one of the hooks). While I tend to use the Malyugin ring in most small pupil cases, this case offers a few challenges that, in my opinion, favor iris retractors.
Q7: Which IOL material would you use in this uveitis patient?
Nick Mamalis The question regarding IOL material is an important one, as uveitis patients are at higher risk for surgical and postoperative complications. When evaluating the biocompatibility of an IOL material, it is important to evaluate both uveal biocompatibility (blood aqueous barrier breakdown and inflammatory cell reactions to the IOL materials) and capsular biocompatibility (lens epithelial cell ongrowth to the IOL surface as well as both anterior and posterior capsule opacification).
For 57 percent of the respondents, hydrophobic acrylic was the material of choice. This material has a moderate to good uveal biocompatibility as well as very good capsular biocompatibility, and studies have found that hydrophobic acrylic IOLs are well-tolerated in patients with uveitis. Approximately one-fourth of the respondents chose hydrophilic acrylic. This material has excellent uveal biocompatibility but potential problems in terms of capsular biocompatibility. Only 8 percent chose silicone, although new generations of silicone show very good uveal biocompatibility and good capsular biocompatibility.
A potential problem is the possible issue with silicone oil adherence to silicone IOLs following vitrectomy with silicone oil injection, which may be necessary in some patients with uveitis. In addition, plate haptic silicone lenses have increased incidence of both anterior and posterior capsule opacification and are usually not a recommended choice for patients with uveitis.
Overall, good results can be obtained with all three of the major types of IOL materials in patients with uveitis despite moderate differences in IOL biocompatibility.
Q8: Noting the presence of vitreous cells intra-operatively, by what route would you administer steroids at the conclusion of surgery (besides topical)?
Stephen Foster Intraocular steroid administration is almost never necessary in the care of a patient with uveitis, and such injection carries with it considerably more risk of complications than does the employment of periocular and/or oral administration. Topical application of corticosteroid could be expected to have little effect in the intermediate or posterior aspects of the globe. Hence, in the effort to maximize the likelihood of success following uveitic cataract surgery, with the discovery of vitreal cells intraoperatively, administering periocular triamcinolone, 40 mg, would be perfectly appropriate, provided the patient has not also had significant steroid-related glaucoma. Observing for effect and adding oral prednisone (1 mg per kg per day with taper) would be appropriate in the event that postoperative inflammation was greater than what one might expect or hope it would be. If the vitreal cells observed intraoperatively were more than trivial in amount, concomitant employment of both periocular and oral corticosteroid therapy would be appropriate.
Q9: What strategy (beside steroid administration) would you use to prevent posterior synechiae in this uveitis patient?
Michael Raizman Eyes with uveitis commonly develop posterior synechiae after cataract surgery. Small areas of adhesion of iris to the edge of the anterior capsulorhexis are usually benign; more extensive synechiae can lead to pupillary block and limit the view of the posterior segment.
Surgical strategies can limit these complications. Avoid excessive trauma to the iris during surgery. Small pupils should be stretched gently to break synechiae and membranes; excessive stretching creates multiple tears in the iris sphincter, more inflammation after surgery and permanent pupil dilation. Iris hooks or a pupil ring are good options. A relatively large rhexis is ideal, and I prefer a 5.5- to 6-mm opening. A smaller rhexis will lead to a small pupil after surgery if synechiae form. If the capsule opening appears too small after the IOL is inserted, it can be enlarged with scissors and forceps. A rhexis larger than the IOL optic might lead to synechiae to the posterior capsule and capture of the optic edge by the pupil. This can be a significant problem, with a tilted IOL and chronic irritation of the iris by the edge of the optic. Some patients require chronic mydriatic therapy after surgery to prevent this complication. Interestingly, creating a peripheral iridectomy seems to increase the likelihood of posterior synechiae formation at the pupil. Perhaps the aqueous flow through the peripheral iridectomy is much greater than that through the pupil. Sulcus placement of an IOL does not necessarily decrease the risk of synechiae formation and may lead to more irritation to the iris.
Q10: How would you manage this patient (Fig. 3) with late bag-IOL dislocation (Array IOL)?
Dennis Lam If the patient is not having a multifocal IOL, I would manage the patient with suture fixation of the dislocated IOL. However, it would be difficult to suture-fixate a multifocal IOL in a well-centered position, and if a multifocal IOL is moderately decentered after the operation, the chance of significant visual symptoms would be high. It would be undesirable to have to further operate on the patient when the suture-fixated IOL is not centered enough.
It is important to explain to the patient the odds of such a risk as well as the potential need for a further operation if significant symptoms occur. If the patient is keen to retain the multifocal IOL and willing to accept these risks, we can go ahead with the surgery. If the patient is not willing to run such a risk, we can exchange the dislocated multifocal IOL with a scleral-fixated sutured PCIOL or exchange with an ACIOL. There are pros and cons for each method. Both are viable and the decision will rest on the experience and preference of the surgeon.
George Williams Dislocation of the entire PCIOL capsular bag complex into the vitreous cavity is perhaps the most complicated type of PCIOL dislocation. The audience responses cover multiple treatment options. Repositioning of in-the-bag dislocation is difficult due to limited access to the haptics, which are typically encased in the bag because of capsular fibrosis. Although elegant suturing techniques to fixate the PCIOL bag complex to either the iris or the sclera can be successful, they tend to be technically demanding and often fail to accurately reposition the lens in the visual axis, which is a significant problem for a multifocal IOL. Significant vitreous disruption often occurs with partial dislocation and is universal in complete dislocation.
For these reasons, I prefer a three-port pars plana approach with posterior infusion and complete posterior vitrectomy in all cases of PCIOL bag complex dislocation. With this approach, it is easier and more controlled to deliver the dislocated PCIOL bag complex into the anterior chamber where it can be exchanged. My usual preference is to use an angle-supported ACIOL, but I will consider iris-sutured fixation if there are contraindications to an ACIOL. The posterior approach also allows for a complete examination of the peripheral retina and treatment of any retinal pathology. I regularly perform prophylactic laser retinopexy because of the increased risk of retinal tears and retinal detachment associated with vitreous disruption.
Q11: How often do you employ CTRs in pseudo-exfoliation patients?
Alan Crandall I certainly do use CTRs in pseudoexfoliation cases. I use them whenever I feel that the zonules are weak. The clues may be seen preoperatively with chamber asymmetry, when the capsulorhexis is difficult to initiate and with wrinkles. I try to reduce all zonule stress by thorough hydrodissection and to minimize the nucleus rotation. I try to wait as long as possible to use the CTR but, as Ken Rosenthal states in Q15, “as early as is necessary” to stabilize the nucleus. CTRs do not prevent late subluxation but may reduce phimosis of the capsule and aid in re-suturing if needed. Overall, it is hard to estimate how often I use CTRs, but it is greater than 20 percent.
Q12: In the absence of any capsule, what IOL would you use?
Brian Little It is reassuring to note that in the absence of any capsular support a convincing majority of surgeons would choose to insert an angle-supported Kelman-style open-looped ACIOL. Modern angle-supported ACIOLs are very safe and reliable with a long and favorable track record. They also are relatively simple to implant.
Many studies have compared the outcomes between ACIOL and scleral-sutured PCIOLs. The headline message is that with good quality surgery, excellent visual outcomes are comparable with both techniques. However, an important caveat is that iris or scleral suturing a PCIOL is intricate surgery and thus takes longer to perform. This is especially the case with scleral suturing, which may be associated with more significant complications—such as choroidal hemorrhage—than is successful ACIOL implantation. However, any suturing technique is also vulnerable to cheese-wiring through tissues and late suture breakage with IOL dislocation. For these and other reasons, the early enthusiasm for sutured PCIOLs has generally waned and many surgeons have now returned to implanting the tried and tested AC- IOLs where appropriate.
Walter Stark I am surprised that 71 percent of respondents chose an ACIOL over a sutured PCIOL in eyes with no capsular support. Perhaps more familiarity with the iris-suture techniques would change many opinions. ACIOLs have been shown to cause more iritis, cystoid macular edema (CME), glaucoma and corneal edema than PCIOLs in eyes with an intact capsule.1 Likewise, ACIOLs cause more complications than sutured PCIOLs in eyes undergoing penetrating keratoplasty and secondary IOL insertion.2
The techniques of PCIOL implantation can be learned and the procedure is not much more difficult than placement of an ACIOL.3 Also, it is much easier to clear vitreous from the wound and the anterior chamber in eyes with a PCIOL than with an ACIOL, leaving a round and not a peaked pupil.
The ability to insert and suture-fixate a PCIOL through a 3.5-mm incision gives the surgeon greater flexibility in treating patients with no capsule support. This technique permits secondary IOL insertion in aphakic patients who are contact lens intolerant, facilitates the management of IOL problems after surgery that require IOL exchange and allows the surgeon to properly treat patients who develop loss of capsule support at the time of cataract surgery.
Q13: Are you comfortable with suturing PCIOLs?
Roger Steinert The response shows that the majority of surgeons have confidence in modern ACIOLs, but 59 percent represents a decline from previous surveys, when the figure was typically 75 percent or higher. Iris suturing has grown rapidly in popularity, essentially equal to scleral fixation. Of course, specific patient pathology—such as iris damage, peripheral synechia or preexisting filtering blebs—may dictate a specific choice for IOL fixation.
Q14: This patient (Fig. 4) has 4+ nuclear sclerosis and very weak zonules. What next?
Dick Mackool The percentage of respondents who would attempt to stabilize the capsule/lens complex by insertion of a CTR and/or the use of capsule retractors increased slightly—from 45 percent to 49 percent—compared with last year’s survey. However, the most common response continues to be to attempt to perform the procedure utilizing phaco without devices, although this figure is down from 36 percent in last year’s survey. This is a desirable trend because the chance of avoiding such complications as capsule rupture or vitrectomy is much greater when capsule retractors are employed. The percentage of those who select the use of either capsule or iris retractors prior to continuing phaco has increased from 18 percent to 26 percent this year. This is a positive and appropriate trend.
Although the survey did not query whether or not the respondents would be likely to use a dispersive viscoelastic in order to assist in stabilization of the lens capsule and nucleus, it probably should have done so. The use of a dispersive viscoelastic to expand the capsular sac and isolate the nucleus or nuclear fragments can be extremely advanta-geous in these situations.
Q15: Which of these does your OR stock?
Ken Rosenthal Despite their cost, which is borne by the surgery center without direct compensation, having CTRs in the OR can be the key to safe removal of a cataract as well as to postoperative stability of the IOL in the presence of zonular laxity, which has resulted in capsular instability. The CTR should be inserted “as early as is necessary and as late as is possible.” On one hand, early insertion provides stability of the capsular bag during phacoemulsification and lens insertion; on the other, it can entrap cortex against the capsular fornix, rendering cortical cleanup more difficult.
In order to avert the need for early CTR insertion, a number of ancillary techniques can be employed. Visco-insufflation, using a retentive viscoelastic such as Healon 5 to expand the capsular bag, can counteract the tendency for the capsule to decenter or to collapse in an area of focal zonular deficiency. Visco-elevation of the nucleus out of the capsular bag followed by supracapsular phacoemulsification can also disassociate the nuclear disassembly forces from the capsular bag and zonules, reducing the risk of their further destabilization. Capsular retaining hooks can be used as well to fixate the bag, but this carries the risk of causing a radial tear in the capsulorhexis, thus further compromising the capsular bag. These maneuvers frequently allow the surgeon to defer the placement of the CTR until the lens insertion phase of the case.
On the other hand, in cases of severe zonular instability, insertion of a CTR creates stability throughout the entire surgical case. Cortex entrapment can be avoided by removal of the anterior and equatorial cortex, then injection of a retentive viscoelastic under the anterior capsular rim, thus displacing the remaining cortex and the nucleus toward the posterior lens capsule and leaving the anterior capsular rim free of any lens material. The CTR can then be inserted just under the anterior capsular rim, placing it as anteriorly as possible, into an area that is now devoid of any cortical material. In order to reduce the stress on the capsular bag, the ring should be placed by partially expressing the ring from the injector prior to placement into the bag, so that it can be placed as far forward as possible, and then, as the inserter is backed out the ring is injected just enough to maintain the ring in the same rotational position, and the ring is “tucked” beneath the anterior capsular rim. Thus the ring can be placed into the capsular bag without having it advance once within the bag.
Cortical entrapment can also be minimized by the use of the Henderson CTR, which has a sinusoid configuration, with multiple point-like contacts with the capsule and with clear spaces in between, from which cortex can be extracted.While most ORs now carry one type of CTR, it is ideal to have a selection of rings and hooks, each with specialized functions, so that in cases of severe capsule-zonular instability, further support of the capsule can be achieved. Despite their high cost, they can result in better outcomes.
Q16: With an intact bag, but very weak zonules, where would you fixate a PCIOL?
Ike Ahmed A CTR, which should only be used with an intact capsular bag, provides enhanced PCIOL centration and may reduce the risk of postoperative dislocation. Surgeons should become familiarized with CTR indications and implantation techniques to manage these complex cases. In the absence of overt bag decentration at the time of surgery, a sutured Cionni ring or CTS is likely not required. In the event of future subluxation, the entire bag-IOL-CTR complex may be sutured to the sclera. However, if profound zonulopathy was present at the time of the surgery, a sutured capsular tension device (Cionni ring or CTS) would be advisable.
Placing a PCIOL in the sulcus in eyes with compromised zonules is suboptimal due to a high risk of subluxation (an intact zonular apparatus is necessary for sulcus support of a PCIOL), and the lack of an IOL or CTR within the capsular bag is likely to hasten capsular contracture with further risk of dislocation.
Q17: Which presbyopia-correcting IOLs can be implanted in patients with weak zonules?
Steve Lane The use of a presbyopia-correcting IOL in the presence of zonular compromise is a multifactorial issue. First, the amount of capsular compromise is critical. An IOL placed within the lens capsule must with a high degree of assurance remain well centered without dislocation or tilt. This is even more important with aspheric designed IOLs, presbyopia-correcting IOLs and toric IOLs, where optical performance will be compromised if the IOL becomes decentered or tilted.
Second, CTRs can be used to aid in-bag stability but often have minimal effect on attaining centration. A modified CTR such as a Cionni ring is most often needed to assure IOL centration.
Third, the performance of each type of IOL will be affected differently if it moves out of its intended place. A small amount of decentration without rotation may be well tolerated with a toric spherical lens. However, if there is rotation and the lens is aspheric, vision would likely be compromised as a result of induced coma and reduction in the cylinder correction.
In general, the present generation of accommodating IOLs should not be placed when the posterior capsule is compromised. Capsular placement of multifocal IOLs should be used with great caution and only if the amount of zonular compromise is small and the likelihood of IOL dislocation is minimal.
Alternatively, a non-aspheric IOL in the bag, with or without a CTR, can be considered. Finally, a multipiece multi- or monofocal IOL with capture of the optic through a well-centered anterior capsulorhexis can be considered and may well offer the best option.
Q18: For a posterior polar cataract (Fig. 5a), I:
Abhay Vasavada Posterior polar cataracts are predisposed to posterior capsule dehiscence during surgery. Cortico-cleaving hydrodissection can lead to hydraulic rupture and should be avoided altogether or performed with extreme caution. It would be logical to perform hydrodelineation to create a mechanical cushion of epinucleus. With conventional hydrodelineation, the cannula is penetrated within the lens substance, causing the fluid to traverse from outside to inside. It is sometimes difficult to introduce the cannula within a firm nucleus, which leads to rocking and stress to the capsular bag and zonules. More important, there is a possibility of fluid being injected inadvertently in the subcapsular plane, leading to inadvertent buildup of hydraulic pressure.
Injecting from core to outside—inside-out delineation—helps to precisely delineate the central core nucleus and avoids subcapsular passage of fluid. Because this is under direct vision, a desired thickness of nucleus-epinucleus cushion can be achieved. The central nucleus can be consumed within the bowl of epinucleus. Following this, first the peripheral nasal half of the epinucleus is stripped off to open up the space between posterior capsule and epinucleus. Next, the peripheral subincisional epinucleus is mobilized with a gentle focal, multiquadrant hydrodissection, using a right-angled or curved hockey cannula. It is safe to hydrodissect at this stage, as the space is already open and hydrorupture is avoided. The entire epinucleus is then aspirated and the central area finally is detached.
According to the audience poll, 45 percent believe that hydrodelineation alone is a good idea. There is an increasing interest in viscodissection, which I believe is a good idea. However, we believe that cortico-cleaving hydrodissection should be avoided until the nucleus is removed and the space between the posterior capsule and epinucleus is opened up.
Q19: After posterior capsular rupture (Fig. 5b), I’d perform the cortical cleanup with:
Lisa Arbisser I am pleased to see the sophistication of the audience responses. Only 5 percent would leave the cortex in place. After the capsule—and, particularly, the anterior hyaloid—is ruptured, the barrier for prostaglandins and other inflammatory mediators is absent. It is particularly important to protect the posterior segment from sequelae such as CME by leaving a clean anterior segment with the least antigenic load. Residual cortex also can impair the postoperative view of the fundus, which always requires a careful indented exam after complicated cataract surgery. Once herniated vitreous is properly removed back to the posterior segment with bimanual vitrectomy, through either a properly sized clear corneal anterior approach or a pars plana sclerotomy, then automated irrigation and aspiration can be considered.
Because there is always a chance of re-presentation of vitreous, coaxial I-A is the least-attractive modality due to greater turbulence and increased chance of displacing vitreous with irrigation aimed posteriorly. Bimanual I-A is preferable, as it allows the irrigation to remain anterior-directed, but both choices allow vitreous incarceration into the I-A port if it re-presents. Vitreous cannot be refluxed from the port and the resultant traction can easily lead to a retinal tear. For this reason, the third choice—bimanual I-A with the vitrector—is safer yet. The default panel setting of I-cut-A is changed, once vitrectomy is done, to I-A-cut so that foot position two is vacuum (allowing followability of cortex), and foot position three can be rapidly engaged to cut any vitreous strand that presents, thereby reducing potential traction.
The fourth choice—dry aspiration under OVD—eliminates all turbulence and is the most controlled method, though it is also the most time consuming. More than one-third of the audience chose this safest methodology.
Q20: With a posterior capsular tear (Fig. 5c), where would you place the IOL?
Kevin Miller Without further information to define the extent of the posterior capsule tear, the majority of respondents would place a three-piece IOL in the ciliary sulcus. Ideally this IOL would have a round-edge optic, large haptics and a posterior haptic angulation. Single-piece acrylic and plate-haptic IOLs are FDA-approved for capsular bag fixation only. They will decenter if placed into the sulcus because of their short overall diameter. Single-piece acrylic lenses have square-edge optics and haptics that, if placed in the sulcus, may cause iris chafe with the sequelae of pigment dispersion, iris transillumination, IOP rise and hyphema. If a posterior capsule tear can be converted successfully into a posterior capsulorhexis, then any style of lens can be placed inside the capsular bag. If a posterior capsule tear is unstable, a three-piece lens can be placed inside the capsular bag only if the optic can be captured securely through the anterior capsulorhexis.
Q21: My PC rupture rate with posterior polar cataracts?
Sam Masket It is interesting to note that there appears to be a trend toward a reduction in the reported incidence of capsule rupture concomitant with surgery for posterior polar cataract. Although this current audience poll may not reflect an accurate assessment, greater than 50 percent of the attendees indicated a capsule rupture rate of less than 15 percent. The inference is that surgeons have “come to grips” with these high-risk cases. In 1999, Abhay Vasavada reported a 36 percent capsule rupture rate in a series of 25 eyes having surgery for this type of cataract,1 and the literature consensus has typically reported approximately a 25 percent rupture rate.
What might account for the reduced rate of capsule rupture in cases with posterior polar cataract? One possible explanation is that these Spotlight sessions on cataract surgery have featured complex case types and helped to disseminate effective management strategies. We cataract surgeons and our patients are indebted to David Chang for organizing this educational highlight.
Q22: In this case with capsular rupture, but without vitreous loss, I would:
Brad Shingleton It is interesting to note that a similar question was asked in 2008 (albeit with vitreous loss) and there is a gratifying trend apparent in the audience responses when the two years are compared.
In 2008, 60 percent of audience members responded that they would immediately inform the patient of the complication and 22 percent would not discuss unless other complications arose later. This year, 69 percent responded that they would inform the patient immediately and only 9 percent would withhold discussion of the surgical complication with the patient. In reviewing this question last year, Ken Rosenthal appropriately noted that “It is the responsibility of an ophthalmologist to act in the best interest of the patient” and added that this includes a prompt, forthright discussion with the patient and family about the problem and potential impact on prognosis. I agree completely and favor full disclosure.
However, in this case with placement of a posterior chamber lens in the sulcus in the absence of vitreous loss, the prognosis is very good. Full disclosure would include discussion with the patient and family on postop day one when they are alert and ready to absorb detailed information, rather than at the time of surgery. Discussion would not focus on the term “complication” but rather on the issue of capsule integrity and the need to support the lens in a position different than other cases. Emphasis would be placed in the high likelihood of an excellent outcome and the need to monitor lens position and posterior segment status. In this case without vitreous loss, it is unlikely that postop care would be significantly different from a standard phacoemulsification procedure. But our patients would be specifically told to call us immediately if any problems developed and reminded that our team is available to them at all times.
Q23: Following posterior (Figs. 6a, 6b) capsular rupture in this polar cataract, I would aspirate the remaining lens with the:
Robert Cionni Too often the posterior polar cataract provides the cataract surgeon an opportunity to practice vitrectomy skills. Management will depend on several factors, including the amount and density of the remaining nuclear material, the amount of remaining cortex, the presence or absence of vitreous prolapse, the characteristics of the posterior capsular opening, the anesthetic modality and the patient’s level of anxiety, and the surgeon’s experience.
No surgeon could be faulted for removing any vitreous that is forward and placing an IOL in the sulcus (preferably with posterior optic capture), in the anterior chamber, or even leaving the patient aphakic and referring to a vitreoretinal specialist for a vitrectomy and removal of the remaining lens material. However, with proper technique the cataract surgeon can usually remove prolapsed vitreous and remaining lens material as well as place a PCIOL or ACIOL.
The first step is recognition of the complication and having the wherewithal to not pull the phaco tip out, causing the chamber to collapse and vitreous to follow the phaco tip out of the incision. Instead, fill the chamber and “plug” the capsular opening with a dispersive OVD through the side-port incision to help tamponade vitreous from further prolapse. Any vitreous that is forward must be dealt with properly before attempting to remove the remaining nucleus and cortex. Either a pars plana or an anterior approach is acceptable, as long as the anterior approach does not include coaxial irrigation and is not performed through the main cataract incision. Instead, hydrate and seal the main incision and make a second side-port incision sized appropriately for either the 20- or 23-gauge vitrectomy cutter. Irrigation will occur through the initial side-port incision.
This technique minimizes or even eliminates fluid egress, which is nearly always followed by vitreous movement out of the incision. I sometimes prefer this approach if the patient has only received topical anesthesia, as the pars plana incision can be uncomfortable and can lead to blood leaking into the vitreous—which, in turn, can lead to a prolonged recovery and perhaps even vitreous fibrosis and retinal detachment. When using this anterior approach it is important to never “pull” vitreous forward; instead, place the vitrector tip through the rent in the capsule and encourage vitreous to move posteriorly. Once vitreous is no longer anterior to the posterior capsule, the surgeon can “re-plug” the opening with an OVD and begin to remove lens material.
In my experience, the most controlled method to remove prolapsed vitreous is the pars plana approach. We now have 23-gauge vitrectomy cutters with speeds as high as 2,500 cuts per minute. Thus, we can often perform a pars plana limited vitrectomy without having to form a conjunctival peritomy, use cautery or place a suture. If using a 20-gauge vitrector, then a peritomy is required as well as sutures. Using the appropriate MVR blade, a stab incision is made 3.5 mm posterior to the limbus in one smooth motion so that the blade is directed toward the center of the globe. The blade is advanced until seen through the pupil and noted to be free of uveal tissue. The vitrector can then be inserted through this incision while irrigation is accomplished through the limbal side-port incision. Always use the highest cut speed and the setting of cut-I-A, not I-A-cut. Note that whenever vitreous is engaged and aspiration is occurring, the cutter must also be active. Likewise, the surgeon should not be pulling backward but instead be moving the tip forward to avoid pulling on the vitreous. The vitrector tip can be brought up through the capsular tear to engage anteriorly prolapsed vitreous; quite often, leaving the tip just behind the rent will encourage the prolapsed vitreous posteriorly.