Management of Retained Lens Material
Management of Retained Lens Material
Updated surgical techniques and technologies are helping to improve visual outcomes.
By Carl D. Regillo, MD, FACS
Retained lens material (RLM) in the vitreous cavity is a potentially serious complication of modern cataract surgery, estimated to occur in 0.3-1.1% of cases.1 Several factors have been identified as increasing the risk of RLM, including hypermature, dense brunescent or posterior polar cataracts, zonular compromise, previous vitrectomy and floppy iris syndrome. Any condition predisposing the eye to intraoperative posterior capsular tear, such as diabetes or pseudoexfoliation, also increases the risk of RLM.
Eyes with RLM can develop elevated IOP, corneal edema, vitreous hemorrhage, retinal detachment and persistent intraocular inflammation, including cystoid macular edema (CME), which usually leads to poor visual acuity.
In cases where only a small amount of cortical material is retained, vitreoretinal surgery may not be necessary. Often, these fragments dissolve on their own. In the meantime, the patient should be treated with topical anti-inflammatory drops and watched closely for elevated IOP, CME and retinal detachment. When larger amounts of lens material or nuclear fragments are retained, pars plana vitrectomy (PPV)/lensectomy is required to remove the fragments (Figure 1), with the goals of reducing IOP and inflammation, repairing any retinal breaks or detachments and ultimately restoring visual acuity.
Figure 1. A small amount of cortical material retained in the vitreous cavity following cataract surgery may dissolve on its own. However, when larger lens or nuclear fragments are retained, they should be removed with subsequent pars plana vitrectomy/lensectomy.
Historically, achieving good visual acuity outcomes after PPV/lensectomy for RLM has been a challenge because complication rates have been high. A look back at all published series since 1980 with 25 or more cases showed that retinal detachments occurred in 8-17% of cases, CME persisted in up to 46% of cases, and visual acuity of 20/40 or better was achieved in only 55% (44-71%) of cases (unpublished data). Based on a retrospective review of all cases of PPV for removal of retained lens fragments performed at Wills Eye Institute from April 1991 through August 1994 (121 eyes),2 my colleagues and I reported visual acuity of 20/40 or better in 3% of eyes before surgery and 68% of eyes after surgery. Retinal detachments occurred in 19 eyes (16%). Eight were noted at the time of vitrectomy and 11 occurred after vitrectomy. The main causes of poor final visual outcome were retinal detachment and CME. Among patients with a final visual outcome of 20/400 or worse, 33% had a detachment, 22% had CME and 11% had elevated IOP.
Large series published more recently provide additional data. Smiddy and colleagues3 reported a retinal detachment rate of 8% and final visual acuity of 20/40 or better in 54% of eyes. Scott and colleagues4 reported a retinal detachment rate of 13% and final visual acuity of 20/40 or better in 56% of eyes, and Merani and colleagues5 reported a retinal detachment rate of 9% and final visual acuity of 20/40 or better in 71% of eyes.
IMPROVING VISUAL OUTCOMES
Efforts to optimize the final outcomes of PPV/lensectomy for RLM have focused on surgical techniques to minimize complications, in particular, CME, corneal edema and retinal detachment. New technologies, by way of enabling widefield viewing and more controlled, less traumatic surgeries, have been beneficial. Taking advantage of updated surgical techniques and technologies, we have made progress. In updating our previously described Wills Eye series with 115 consecutive cases performed from 2002-2003, my colleagues and I found that, excluding preexisting retinal conditions, 68% of eyes had 20/40 or better visual acuity postoperatively (unpublished data). Eight of the eyes (7%) had retinal detachments, four prior to vitrectomy and four after vitrectomy. Preoperative patient characteristics were similar in both series. Among the 2002-2003 patients, 70% had preoperative visual acuity of less than 20/200.
Reducing complications associated with RLM removal by PPV/lensectomy involves not only the surgery, but management throughout the entire perioperative period, beginning with the cataract surgeon. Here, I describe what are considered best practices for managing RLM based on the literature and collective experience of vitreoretinal surgeons.
Following a capsular rupture, if vitreous has migrated into the anterior chamber, the cataract surgeon should remove it if possible. It is especially important to check for vitreous to the wound, which tends to increase the risk of complications, including endophthalmitis. The cataract surgeon should remove any easily accessible lens material but avoid blind or aggressive maneuvers. Making pars plana incisions to retrieve lens material is not recommended. The cataract surgeon should proceed with IOL implantation if it can be done safely with the IOL securely in place. Wounds should be sutured so they remain sealed during any subsequent surgery.
Immediately following the cataract surgery procedure, the cataract surgeon should initiate aggressive treatment for inflammation with steroid drops every 2 hours while the patient is awake as well as nonsteroidal anti-inflammatory drops. Drops to control IOP should also be prescribed. Within 1 week of cataract surgery, the patient should see a vitreoretinal specialist for a consultation.
It is not completely clear how the duration of time before PPV/lensectomy affects outcomes in RLM cases, but the general consensus is it should be performed within 3 weeks of the cataract procedure. In many cases, waiting a week or two is beneficial because it allows for some resolution of corneal edema and the acute inflammation associated with the cataract surgery. However, PPV/lensectomy should be performed sooner in some situations. If IOP remains significantly elevated despite treatment, I schedule surgery to take place within 48 hours or so after my consultation. Also, because corneal edema usually limits my view into the eye when I first see these patients, I perform a B-scan to make sure the retina is not detached. If it is, I proceed to the OR immediately.
In all RLM cases, prior to vitrectomy, even if an IOL was implanted at the time of cataract surgery, I obtain all of the measurements and perform the IOL calculations necessary for IOL placement. This allows me, at the end of my procedure, to place the IOL if it is not already there, or to replace it if it is not secure.
INTRAOPERATIVE TECHNIQUES AND TIPS
Visualization is often a challenge during PPV/lensectomy for RLM. The cornea may not be clear due to edema, and the pupil may be small because of inflammation. The wide-field viewing systems and wide-angle illumination probes available for today's surgical platforms are an asset in situations like this, and I do not hesitate to manually stretch the pupil.
My preferred surgical approach is a three-port, 23-gauge vitrectomy. If the RLM to be addressed consists of small fragments and does not include much nuclear material, it is often possible to remove it using only the vitrectomy cutting probe. It can be helpful to utilize the light pipe to guide the fragments into the cutter.
For moderate sized or more dense material, emulsification with a phacofragmatome, i.e., pars plana lensectomy, is necessary. At this point, the case becomes much more challenging because phaco in the posterior segment increases the risk for retinal tears and detachments. Avoiding the creation of retinal breaks with the phaco tip and ensuring all RLM is removed from the anterior chamber and posterior segment all the way to the periphery are primary safety and efficacy concerns. Frequently, rather than floating freely, fragments are embedded deep into the vitreous or far anteriorly over the pars plana area. Therefore, ensuring the vitrectomy is complete and the hyaloid is lifted from the retinal surface and carefully inspecting the retinal periphery and vitreous base with scleral depression are key factors for success. Triamcinolone is a useful adjunct for improving visualization of vitreous gel and confirming complete vitrectomy has been achieved.
Regardless of the surgical platform and phacofragmentation technology being employed, having a good hold of the lens material at the tip is crucial. When the fragments are not too dense, standard phaco settings do the job adequately. However, if emulsification is not progressing in a timely manner and the lens fragments are not holding well to the tip, I do not hesitate to gradually increase vacuum and phaco power. Under suction, I engage the fragments and bring them to the mid-vitreous, away from ocular structures, to emulsify them. I usually hold the light pipe behind the fragments for extra support.
After it appears that all RLM is removed, the anterior chamber should be irrigated to remove any fragments that may be trapped in the angle. At the end of the case, the periphery should be meticulously inspected for breaks. If any are present, they should be treated on the spot with laser. Finally, a commonly used strategy to help control postoperative inflammation is to leave a small amount of triamcinolone (2 mg/0.05 ml) in the eye.
Depending on where I am performing a particular case, I use either the ACCURUS® Surgical System (Alcon) or the CONSTELLATION® Vision System (Alcon). The ACCURUS® System has worked well for me in these cases, but I have found the CONSTELLATION® System to be somewhat more efficient when I am using only the vitrectomy probe to remove small lens fragments because of its higher aspiration in conjunction with improved IOP control.
I have also found that when I need to use the fragmatome, the CONSTELLATION® System emulsifies the largest and densest fragments more efficiently. It includes integrated pressurized infusion with IOP control, which not only keeps the globe from collapsing from high suction forces, but also automatically maintains IOP in the surgeon's desired range throughout the entire procedure. Less IOP fluctuation means a more stable and controlled, gentler procedure. Currently, the fragmatome for the CONSTELLATION® Vision System is 20 gauge, so when I need it, I enlarge one of my 23-gauge sclerotomies to introduce it into the eye.
Another option for lensectomy in RLM cases is to use the INFINITI® Vision System (Alcon) with the OZil® torsional phaco handpiece. I use this approach when I am dealing with dense and hard RLM and do not have access to the CONSTELLATION® System for a particular case. Surgeons Sunir Garg, MD, and R. Gary Lane, MD, recently published a paper on this.6 Torsional phaco tends to be more efficient than traditional phaco. It creates less turbulence in the eye and draws lens fragments to the phaco tip, rather than repulsing them, which helps to protect the retina and decrease the risk of breaks. The OZil® torsional handpiece recently became available with the CONSTELLATION® System as well.
CLOSE POST-OP MONITORING
Following PPV/lensectomy for RLM, it is important to closely monitor patients for inflammation, elevated IOP and signs of peripheral retinal tears or detachments. I see these patients one day, 1 week, 4 weeks and 8 weeks after surgery. I follow them for no less than 3 months. I prescribe topical steroids and topical nonsteroidal anti-inflammatory drops, which are tapered slowly over 6 to 8 weeks, or longer if necessary. If visual acuity is not improving as expected by the four-week visit, I obtain OCT scans to check for CME. If CME is detected, I treat it aggressively with a sub-Tenon's or intravitreal injection of triamcinolone.
Once the course of topical anti-inflammatory treatment is complete, if no CME is present and visual acuity has reached or is close to its potential, the patient returns to the cataract surgeon for a refraction. I usually see the patient once more at six months after PPV/lensectomy. If no problems have arisen by that time, I can be confident that the best possible outcome has been achieved.
1. Scott IU, Flynn HW. Retained lens fragments after cataract surgery. Ophthalmol Clin N Am 2001;14:675-679.
2. Borne MJ, Tasman W, Regillo C, Malecha M. Outcomes of vitrectomy for retained lens fragments. Ophthalmology 1996;103(6):971-976.
3. Smiddy WE, Guererro JL, Pinto R, Feuer W. Retinal detachment rate after vitrectomy for retained lens material after phacoemulsification. Am J Ophthalmol 2003;135(2):183-187.
4. Scott IU, Flynn HW, Smiddy WE, et al. Clinical features and outcomes of pars plana vitrectomy in patients with retained lens fragments. Ophthalmology 2003;110(8):1567-1572.
5. Merani R, Hunyor AP, Playfair TJ, et al. Pars plana vitrectomy for the management of retained lens material after cataract surgery. Am J Ophthalmol 2007;144(3):364-370.
6. Garg SJ, Lane RG. Pars plana torsional phacoemulsification for removal of retained lens material during pars plana vitrectomy. Retina 2011;31(4):804-805.
Dr. Regillo is the director of the Wills Clinical Retina Research Unit and professor of Ophthalmology at Thomas Jefferson University School of Medicine in Philadelphia.
CONSTELLATION® Vision System Indications for Use With Laser
Indications for Use: The CONSTELLATION® Vision System is an ophthalmic microsurgical system that is indicated for both anterior segment (i.e., phacoemulsification and removal of cataracts) and posterior segment (i.e., vitreoretinal) ophthalmic surgery.
The PUREPOINT® Laser is indicated for use in photocoagulation of both anterior and posterior segments of the eye including:
• Retinal photocoagulation, panretinal photocoagulation and intravitreal endophotocoagulation of vascular and structural abnormalities of the retina and choroid including: Proliferative and nonproliferative retinopathy (including diabetic); choroidal neovascularization secondary to age-related macular degeneration; retinal tears and detachments; macular edema, retinopathy of prematurity; choroidal neovascularization; leaking microaneurysms.
• Iridotomy/Iridectomy for treatment of chronic/primary open angle glaucoma, acute angle closure glaucoma and refractory glaucoma.
• Trabeculoplasty for treatment of chronic/primary open angle glaucoma and refractory glaucoma.
• And other laser treatments including: internal sclerostomy; lattice degeneration; central and branch retinal vein occlusion; suturelysis; vascular and pigment skin lesions.
Caution: Federal (USA) law restricts this device to sale by, or on the order of, a physician.
Contraindications: Patients with a condition that prevents visualization of target tissue (cloudy cornea, or extreme haze of the aqueous humor of the anterior chamber of vitreous humor) are poor candidates for LIO delivered laser treatments.
Complications: Corneal burns, inflammation, loss of best-corrected visual acuity, loss of visual field and transient elevations in intraocular pressure can occur as a result of ophthalmic laser treatment. Unintentional retinal burns can occur if excessive treatment beam power or duration is used.
Warnings and Precautions:
• The disposables used in conjunction with Alcon instrument products constitute a complete surgical system. Use of disposables and handpieces other than those manufactured by Alcon may affect system performance and create potential hazards.
• Attach only Alcon supplied consumables to console and cassette luer fittings. Do not connect consumables to the patient's intravenous connections.
• Mismatch of consumable components and use of settings not specifically adjusted for a particular combination of consumable components may create a patient hazard.
• Vitreous traction has been known to create retinal tears and retinal detachments.
• The closed loop system of the CONSTELLATION® Vision System that adjusts IOP cannot replace the standard of care in judging IOP intraoperatively. If the surgeon believes that the IOP is not responding to the system settings and is dangerously high, this may represent a system failure. Note: To ensure proper IOP Compensation calibration, place infusion tubing and infusion cannula on a sterile draped tray at mid-cassette level during the priming cycle.
• Leaking sclerotomy may lead to post operative hypotony.
• Back scattered radiation is of low intensity and is not harmful when viewed through a protective filter. All personnel in the treatment room must wear protective eyewear, OD4 or above at 532nm, when the system is in Standby/Ready mode as well as during treatment. The doctor protection filter is an OD greater than 4 at 532nm.
• Important Safety Information: Warnings and Cautions: A complete listing is available in the CONSTELLATION® Vision System Operators Manual. To obtain a copy, please contact Alcon Customer Service.
INFINITI® System Indications for Use
Indication: The INFINITI® Vision System with OZil® IP is indicated for emulsification and removal of cataracts, vitreous aspiration and cutting associated with anterior vitrectomy, and bipolar coagulation.
Caution: Federal (USA) law restricts this device to sale by, or on the order of, a physician.
Warnings: Appropriate use of INFINITI® Vision System parameters and accessories is important for successful procedures. Use of low vacuum limits, low flow rates, low bottle heights, high power settings, extended power usage, power usage during occlusion conditions (beeping tones), failure to sufficiently aspirate viscoelastic prior to using power, excessively tight incisions, and combinations of the above actions may result in significant temperature increases at incision site and inside the eye, and lead to severe thermal eye tissue damage.
Adjusting aspiration rates or vacuum limits above the preset values, or lowering the IV pole below the preset values, may cause chamber shallowing or collapse which may result in patient injury.
When filling handpiece test chamber, if stream of fluid is weak or absent, good fluidics response will be jeopardized. Good clinical practice dictates the testing for adequate irrigation and aspiration flow prior to entering the eye.
Ensure that tubings are not occluded or pinched during any phase of operation.
The consumables used in conjunction with Alcon instrument products constitute a complete surgical system. Use of consumables and handpieces other than those manufactured by Alcon may affect system performance and create potential hazards.
AEs/Complications: Use of the NeoSoniX®, OZil® torsional, U/S, or AquaLase® handpieces in the absence of irrigation flow and/or in the presence of reduced or lost aspiration flow can cause excessive heating and potential thermal injury to adjacent eye tissues.
ATTENTION: Reference the Directions for Use labeling for a complete listing of indications, warnings and precautions.
Maria H. Berrocal, MD, has consulted for Alcon and Alimera.
Timothy G. Murray, MD, is a consultant for Alcon and ThromboGenics, Inc.
Carl D. Regillo, MD, has received research support from, and provided consulting for, Alcon and Bausch + Lomb. He has consulted for Abbott Medical Optics (AMO).
Wayne A. Solley, MD, has received honoraria and educational grants from Alcon.
|To watch videos of the procedures discussed in these articles, visit the Retinal Physician home page (www.retinalphysician.com) and click on the DIGITAL SUPPLEMENTS tab.
Retinal Physician, Issue: November 2011