Facilitating cortical aspiration after insertion of a capsular tension ring

Facilitating cortical aspiration after insertion of a capsular tension ring

TECHNIQUE Facilitating cortical aspiration after insertion of a capsular tension ring Richard S. Koplin, MD, Emily Waisbren, MD, David C. Ritterband,...

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TECHNIQUE

Facilitating cortical aspiration after insertion of a capsular tension ring Richard S. Koplin, MD, Emily Waisbren, MD, David C. Ritterband, MD, John A. Seedor, MD

We describe a simple, effective technique to prevent the cortical entrapment that can occur after a capsular tension ring (CTR) is implanted during phacoemulsification. Before the epinucleus has been removed, the blunt tip of an ophthalmic viscosurgical device (OVD) cannula is burrowed centrally in the cortical/epinuclear plate and OVD is injected as the cannula is advanced. The cannula is turned superiorly and dissection continued to the lens equator. The cleavage plane is extended for approximately 2 clock hours in the direction of the intended CTR insertion. The CTR is then inserted below the cortical/epinuclear plate. Financial Disclosure: None of the authors has a financial or proprietary interest in any material or method mentioned. J Cataract Refract Surg 2016; 42:810–812 Q 2016 ASCRS and ESCRS Online Video

Nagamoto and Bissen-Miyajima1 and Hara et al.2 developed the capsular bag–supporting ring independently. Although the primary intent was to create a device to maintain the circular contour of the capsular bag, the authors also created an effective approach to the management of zonular weakness. Legler et al.A were the first to describe placing an open-ringed poly(methyl methacrylate) (PMMA) capsular tension ring (CTR) in a human eye during cataract surgery. Since then, CTRs of various designs have been introduced.3 All the designs involve a circumferential open-ended ring manufactured of PMMA with blunt end pieces. Ring diameters range from 12.0 to 13.5 mm; ring thickness is approximately 0.22 mm. Many surgeons find a CTR to be useful in cases in which the pathology of the zonular fibers is associated with instability of the capsular bag during phacoemulsification surgery. Placing uniform tension circumferentially against the equator of the lens capsule, which

Submitted: December 22, 2015. Final revision submitted: April 19, 2016. Accepted: April 24, 2016. From the New York Eye and Ear Infirmary of Mount Sinai, New York, New York, USA. Corresponding author: Emily Waisbren, MD, New York Eye and Ear Infirmary of Mount Sinai, 310 East 14th Street, Suite 219, New York, New York 1003-4201, USA. E-mail: [email protected]

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Q 2016 ASCRS and ESCRS Published by Elsevier Inc.

applies centrifugal pressure and decreases tension across the zonular fibers, is thought to enable surgeons to apply less stress to existing zonular fibers, as aspiration draws adherent cortex centrally from the peripheral capsule. As potentially useful as the CTR might be in cases with zonular pathology, CTR placement may make efficient aspiration of cortex more difficult. This unintended consequence is secondary to entrapment of cortex between the ring and the capsule. Henderson and Kim4 developed a CTR that was shaped to prevent trapping of the cortex and obviate the difficulty of aspirating cortex trapped between the ring and the equatorial capsule. However, in our experience, the device demonstrated limited efficacy. We report a technique that uses ophthalmic viscosurgical device (OVD) dissection to assist in the safe and effective insertion of the Morcher CTR (Morcher GmbH) in the plane between the residual cortex and the capsular bag. The procedure in most cases avoids or lessens the nuisance of the equatorial cortex being trapped against the capsule by the overlying CTR. An intact epinucleus attached to underlying cortex is required to develop a continuous cleavage plane since the 2 tissues appear to elevate cohesively on dissection, whereas attempting the technique with cortex alone seems to create an erratic plane of dissection. SURGICAL TECHNIQUE After all nuclear lens material has been successfully removed and the epinucleus remains, the cannula http://dx.doi.org/10.1016/j.jcrs.2016.05.002 0886-3350

TECHNIQUE: CORTICAL ASPIRATION AFTER CTR INSERTION

Figure 1. A defect is created in the sheet of cortex.

attached to the OVD syringe is used to dissect a small defect in the cortical/epinuclear plate in the paracentral area of the lens (Figure 1). Using the OVD, the surgeon slowly advances the cannula through the defect to burrow safely through to the clear posterior capsule. After the surgeon has identified clear capsule (noted by a brightening red reflex), the cannula is turned superiorly as it is advanced and simultaneously injects small amounts of OVD to identify and delineate the cleavage plane (Figure 2). This ensures efficient insertion of the CTR along a continuous plane under the cortical/epinuclear plate (Video 1, available at http://jcrsjournal.org). The CTR is inserted through the defect and advanced under the dissected epinuclear/cortical plane while slight forward pressure is applied to the insertion device (Figure 3). The CTR inserter should be held below the edge of the cortical/epinuclear plate to ensure that the ring remains in the correct plane. This is followed by standard irrigation/aspiration of the cortical material. Although it may be difficult for the surgeon to assure himself or herself that the CTR is completely posterior to the cortex, the relative ease of cortex removal without gross movement of the ring–capsular

Figure 3. The CTR is inserted through the defect and advanced under the dissected cortex/epinucleus plane while applying slight forward pressure on the insertion device.

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Figure 2. The cannula is turned superiorly while advancing and simultaneously injecting small amounts of OVD in the plane between the cortex and the posterior capsule.

complex will indicate that the CTR is properly positioned and the technique has worked as expected. Results The technique has been performed uneventfully in more than 24 cases using Morcher rings of various sizes with reasonable consistency. DISCUSSION Zonular weakness can result from trauma, previous surgery, mature cataracts, high myopia, and, most commonly, pseudoexfoliation. It can also occur with systemic disorders that influence the ciliary zonular fibers, such as Marfan syndrome, Marchesani syndrome, scleroderma, homocystinuria, spherophakia, porphyria, and hyperlysinemia. The CTR is designed to stabilize the capsule both intraoperatively and postoperatively, and the design has been evolving for the past 10 to 15 years.3 It is presumed that due to similar ring designs, the technique will work with all CTR models. If the technique is performed as described, puncture of the posterior capsule is unlikely. The most likely complication is the uneven delivery of the ring through the intended dissection plane, which could lead to irregular entrapment of cortex. The surgeon must be careful to avoid dropping the trailing edge of the ring directly on top of the cortical/epinuclear plate at the conclusion of the insertion process. The optimum timing for CTR implantation has been studied. Bayraktar et al.5 report that in eyes with pseudoexfoliation, placing the ring before phacoemulsification decreased zonular dialysis during surgery and improved intraocular lens fixation. Conversely, Ahmed et al.6 report that the ideal implantation time was after extraction of the nuclear and cortical material; if the CTR was implanted before extraction, it was difficult to remove the cortical material, leading to capsule torque and displacement.

J CATARACT REFRACT SURG - VOL 42, JUNE 2016

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TECHNIQUE: CORTICAL ASPIRATION AFTER CTR INSERTION

Our technique addresses the potential difficulty inherent in removing cortical material after CTR placement. Careful OVD dissection of the capsule from the residual cortical/epinuclear plate creates a plane, which enables safe and effective insertion of a CTR and subsequent aspiration of the residual lens material while lessening insult to the remaining fragile zonular fibers. WHAT WAS KNOWN  It is understood that a CTR may improve support of the capsular bag in cases of zonular weakness.  Although early placement of a CTR reduces stress on the remaining zonular fibers, it can complicate the surgery when it is placed in the capsular bag prior to complete removal of lens material. WHAT THIS PAPER ADDS  Dissecting the plane between the capsular bag and the cortex using an OVD allows the CTR to be placed behind the cortex, which facilitates cortical removal.

2. Hara T, Hara T, Yamada Y. “Equator ring” for maintenance of the completely circular contour of the capsular bag equator after cataract removal. Ophthalmic Surg 1991; 22:358–359 3. Weber CH, Cionni RJ. All about capsular tension rings. Curr Opin Ophthalmol 2015; 26:10–15 4. Henderson BA, Kim JY. Modified capsular tension ring for cortical removal after implantation. J Cataract Refract Surg 2007; 33:1688–1690 € Capsular ten€c‚u €ksu €mer Y, Yılmaz OF. 5. Bayraktar S, Altan T, Ku sion ring implantation after capsulorhexis in phacoemulsification of cataracts associated with pseudoexfoliation syndrome; intraoperative complications and early postoperative findings. J Cataract Refract Surg 2001; 27:1620–1628 6. Ahmed IIK, Cionni RJ, Kranemann C, Crandall AS. Optimal timing of capsular tension ring implantation: Miyake-Apple video analysis. J Cataract Refract Surg 2005; 31:1809– 1813

OTHER CITED MATERIAL A. Legler U, Witschel BM, Lim SJ, Kurata Y, Apple DJ, “The Capsular Ring: A New Device for Complicated Surgery,” presented at the 3rd American-International Congress on Cataract, IOL and Refractive Surgery, Seattle, Washington, USA, May 1993

First author: Richard S. Koplin, MD

REFERENCES 1. Nagamoto T, Bissen-Miyajima H. A ring to support the capsular bag after continuous curvilinear capsulorhexis. J Cataract Refract Surg 1994; 20:417–420

J CATARACT REFRACT SURG - VOL 42, JUNE 2016

New York Eye and Ear Infirmary of Mount Sinai, New York, New York, USA