CASE REPORT

Comparison of 2 techniques for managing posterior polar cataracts: Traditional phacoemulsification versus femtosecond laser–assisted cataract surgery Brian D. Alder, MD, Kendall E. Donaldson, MD, MS

We report 2 patients with bilateral, visually significant posterior polar cataracts who had traditional phacoemulsification in 1 eye and femtosecond laser–assisted cataract surgery in the fellow eye. In both cases, the eye that had femtosecond laser–assisted cataract surgery developed a posterior capsule rupture during lens removal; in 1 eye, there were also retained nuclear fragments. Although visual outcome was excellent in both eyes of both patients, it appears that traditional phacoemulsification with extensive hydrodelineation is the preferable treatment method for posterior polar cataracts. Financial Disclosure: Neither author has a financial or proprietary interest in any material or method mentioned. J Cataract Refract Surg 2014; 40:2148–2151 Q 2014 ASCRS and ESCRS

Posterior polar cataracts can pose a challenge for cataract surgeons in cases involving adherence between the posterior capsule and the posterior aspect of the lens. In these cases, there is a higher risk for posterior capsule rupture and resultant vitreous loss, leading to anterior or posterior vitrectomy and possible retained lenticular material. The incidence of posterior capsule rupture has been reported as 15.5% to 26.0%.1,2 Hydrodelineation of the nuclear lamellae is a technique used to facilitate cataract removal and reduce the risk for posterior capsule rupture in these cases. The use of femtosecond laser assistance in these patients has not been widely described. We report 2 patients with bilateral, visually significant posterior polar cataracts who had traditional phacoemulsification in 1

Submitted: May 13, 2014. Final revision submitted: August 5, 2014. Accepted: August 8, 2014. From the Bascom Palmer Eye Institute of Plantation, Plantation, Florida, USA. Corresponding author: Kendall E. Donaldson, MD, MS, Bascom Palmer Eye Institute of Plantation, 8100 Southwest 10th Street, Crossroads 3, 3rd Floor, Plantation, Florida 33324, USA. E-mail: [email protected].

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Q 2014 ASCRS and ESCRS Published by Elsevier Inc.

eye and femtosecond laser–assisted cataract surgery in the fellow eye. CASE REPORTS Case 1 A 61-year-old man presented to our clinic for cataract evaluation on February 8, 2013. Congenital cataracts had been diagnosed when he was 10 years old, but only recently had he noticed a decline in his vision. He was having difficulty reading in dim light and with night driving because of glare. The corrected distance visual acuity (CDVA) was 20/40 in both eyes. Posterior polar cataracts were diagnosed (Figure 1). Femtosecond laser–assisted cataract surgery was performed in the right eye on May 13, 2013. The Catalys laser (Abbott Medical Optics, Inc.) was used to perform uneventful capsulorhexis and lens fragmentation (4 segments with 350 mm grids) (Figure 2). The bed was shifted, and the patient was prepped and draped as for phacoemulsification. The primary wound and paracentesis were created manually, and an ophthalmic viscosurgical device (OVD) was injected into the anterior chamber. The free-floating capsule was removed using a Utrata forceps, and hydrodissection and limited hydrodelineation were done. The lens rotated freely within the capsular bag. The phaco handpiece was placed within the thin hemigroove created by the laser, and the hemisections were separated. The nucleus was rotated, and the hemisections were again separated perpendicular to the first plane, resulting in 4 quadrants. The chamber appeared to deepen at this point. When the first quadrant http://dx.doi.org/10.1016/j.jcrs.2014.09.030 0886-3350

CASE REPORT: COMPARISON OF 2 TECHNIQUES FOR POSTERIOR POLAR CATARACTS

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vitrectomy. A 3-piece intraocular lens (IOL) was placed in the ciliary sulcus. On postoperative day 1, the CDVA in the right eye was 20/20. Traditional phacoemulsification with extensive hydrodelineation was performed in the left eye on June 17, 2013. The plaque peeled off the posterior capsule, and the capsule remained intact. On postoperative day 1, the CDVA in the left eye was 20/20.

Case 2

Figure 1. Case 1, right eye. Posterior polar cataract.

was removed, it became clear that there was a split in the posterior capsule that was perfectly aligned with the primary groove made by the laser (Figure 3). The first 3 quadrants were removed with a copious amount of the OVD beneath the sections; however, the fourth quadrant descended into the vitreous, necessitating a pars plana

A 66-year-old man was referred to our clinic by a local cataract surgeon for treatment of congenital cataracts in both eyes. At presentation, the patient complained of extreme glare that made him unable to drive safely at night. The CDVA was 20/40 in both eyes. With glare testing, the CDVA was 20/40 in the right eye and 20/50 in the left eye. Posterior polar cataracts were diagnosed. Traditional cataract surgery was performed in the left eye on March 17, 2014. Extensive hydrodelineation was performed and the surgery was uneventful, with an intact capsular bag. On postoperative day 1, the CDVA was 20/ 20 in the left eye. Femtosecond laser–assisted cataract surgery was performed in the right eye on March 31, 2014. Uneventful laser-assisted capsulorhexis and lens fragmentation with the surgeon's standard segmentation (4 quadrants with

Figure 2. Case 1, right eye. Images from the femtosecond laser showing the posterior capsule opacity (top) and the inclusion of the entire posterior polar cataract within the 500 mm safety zone (bottom) to protect the posterior capsule.

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CASE REPORT: COMPARISON OF 2 TECHNIQUES FOR POSTERIOR POLAR CATARACTS

Figure 3. Case 1, right eye. Posterior capsule tear is noted after removal of part of the lens nucleus.

Figure 4. Case 2, right eye. All nuclear fragments were removed despite the presence of a large posterior capsule tear.

350 mm grids) were performed. The patient was prepped and draped as for phacoemulsification. As with Case 1, the wound was created and the capsule removed uneventfully. Hydrodissection and hydrodelineation resulted in a freely rotating lens within the capsular bag. After separation of the hemisections, a split in the posterior capsule was clearly visible in the same orientation as the primary subdivision of the lens. The OVD was injected beneath the lenticular material to elevate it into the anterior chamber and to limit vitreous prolapse. All 4 quadrants were safely removed (Figure 4). An anterior vitrectomy was performed, and a 3-piece IOL was placed within the ciliary sulcus. On postoperative day 1, the right-eye CDVA was 20/20 (Figure 5).

bag and posterior gas escape should have been visible on the OCT images. It is crucial to diagnose posterior polar cataracts and to differentiate between posterior subcapsular cataracts, commonly seen in younger patients and diabetics, and congenital posterior polar cataracts, which were present in the 2 patients presented here. Typically, patients with congenital posterior polar cataracts have a long history of the condition, making the diagnosis more straightforward. Additionally, posterior polar cataracts are generally more elevated, very well circumscribed, and associated with circumferential rings that delineate them from the surrounding capsule. Posterior polar cataracts are flatter and are characterized by plaque on the posterior capsule.

DISCUSSION In patients with posterior polar cataracts, careful hydrodelineation is the preferred method because it reduces the risk for posterior capsule rupture. Although this is easily performed during traditional phacoemulsification, it might be more difficult to hydrodelineate the nuclear lamellae adequately after laser-based lens fragmentation. Furthermore, gas bubbles formed during laser application could become trapped behind lens material, placing extra tension on an already weakened posterior capsule. This could result in capsular distension syndrome, in which increasing pressure within the capsular bag results in posterior capsule rupture. Although capsular block syndrome (CBS) is certainly a potential consideration, it is doubtful in these cases because the images from optical coherence tomography (OCT) during the laser application showed no irregularities. If it were CBS with posterior rupture attributable to gas distension within the capsular bag, expansion of the capsular

Figure 5. Case 2, right eye. On postoperative day 1, examination showed minimal corneal edema, good IOL centration, and CDVA of 20/20.

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CASE REPORT: COMPARISON OF 2 TECHNIQUES FOR POSTERIOR POLAR CATARACTS

They are not associated with the posterior capsule complications that commonly correlate with posterior polar cataracts. Although it is difficult to determine exactly when the posterior capsule ruptured in these 2 cases, it might have occurred because of the cavitation bubbles created during the laser procedure, which would increase tension within the capsular bag, resulting in posterior movement of gas through the weakened central area of attachment between the posterior capsule and the lenticular opacity. However, this is unlikely because no irregularities were noted on OCT during the laser application. Alternatively, because the lens fragmentation was performed using the laser, hydrodelineation most likely did not occur through the usual planes within and around the lens (nuclear and epinuclear) structure, thus more conventional hydrodissection was inadvertently performed. When the 2 hemispheres were gently separated, it became clear that the posterior capsule was splitting in the same plane along with the lens. A central circular hole was visible within the posterior capsule, consistent with the attachment between the lens opacity and the posterior capsule. In cases of posterior polar cataract, perhaps the posterior safety boundary for laser application could be adjusted during laser-assisted cataract surgery to include the entire posterior opacity, with significant excess (changing the posterior safety zone from the conventional 500 mm width to a 700 to 800 mm zone, thus increasing the thickness of the posterior plate). This would create a thicker posterior plate, which could then be more effectively hydrodelineated, facilitating separation from the posterior capsule. More conservatively, perhaps no lens fragmentation should be performed; instead, only corneal incisions and capsulotomy followed by manual hydrodelineation and

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lens segmentation/fragmentation methods should be performed, thus avoiding the inherent consequences associated with inadvertent hydrodissection and divide-and-conquer technique facilitated and necessitated by the laser's predefined quadrants. Traditional phacoemulsification and modified laser-assisted cataract surgery with extensive hydrodelineation are the preferred methods for treatment of posterior polar cataracts. Femtosecond laser–assisted cataract surgery can be considered in these cases with a modified technique (limited to corneal and capsule applications) to minimize posterior capsule stress and allow adequate hydrodelineation.A REFERENCES 1. Kumar S, Ram J, Sukhija J, Severia S. Phacoemulsification in posterior polar cataract: does size of lens opacity affect surgical outcome? Clin Exp Ophthalmol 2010; 38:857–861 2. Osher RH, Yu BC-Y, Koch DD. Posterior polar cataracts: a predisposition to intraoperative posterior capsular rupture. J Cataract Refract Surg 1990; 16:157–162

OTHER CITED MATERIAL A. Srivastava S, Vasavada AR, Raj SM, Vasavada V, Vasavada V, “Cushioning Posterior Polar Cataract: Femtosecond-LaserBased Approach,” presented at the ASCRS Symposium on Cataract, IOL and Refractive Surgery, Boston, Massachusetts, USA, April 2014

J CATARACT REFRACT SURG - VOL 40, DECEMBER 2014

First author: Brian D. Alder, MD Bascom Palmer Eye Institute of Plantation, Plantation, Florida, USA

Comparison of 2 techniques for managing posterior polar cataracts: Traditional phacoemulsification versus femtosecond laser-assisted cataract surgery.

We report 2 patients with bilateral, visually significant posterior polar cataracts who had traditional phacoemulsification in 1 eye and femtosecond l...
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