Article Date: 11/1/2011

Removing an IOL from the Vitreous Cavity

Removing an IOL from the Vitreous Cavity

A new approach eliminates the need for a limbal incision and proves to be more efficient.

By Wayne A. Solley, MD

Even though modern cataract surgery techniques and new IOL designs have significantly reduced all types of associated complications, the potential for IOL dislocation still exists. It has been estimated to occur in 0.2% to 3% of cases.1,2 The extent of dislocation can range from slight decentration to partially out of the capsular bag to complete luxation into the posterior segment. Pseudoexfoliation is a common cause of both in-the-bag and out-of-the-bag dislocations, and out-of-the-bag scenarios are often due to some sort of capsular compromise, such as a rupture or tear, at the time of surgery.3,4 Dislocations can occur during cataract surgery or even months or years afterward.4-7

As long as a patient's overall health and ocular health permit it, surgery to remove, exchange or reposition the IOL is typically recommended in order to alleviate potentially annoying symptoms and restore optimal vision. In some cases, an anterior-segment (limbal) surgical approach can be used. However, when the IOL has dislodged fully into the vitreous cavity, pars plana vitrectomy (PPV), which is considered to be safe and effective for this purpose, is a much safer approach.8

While vitreoretinal surgeons don't see as many cases of dislocated IOLs as other posterior segment conditions and pathology, dislocated IOLs are not rare in our operating rooms. Given the increasing number of patients who undergo cataract surgery each year — as well as the aging of the overall population — we can reasonably expect to be called on to manage these cases more frequently in the future.

I have recently begun using a new technique to remove IOLs that have dislodged and fallen into the vitreous cavity. I use the CONSTELLATION® Vision System for PPV, then cut the IOL into several strips and remove each one through the pars plana. With this method, there is no need to make a corneal limbal incision or raise the IOL into the front of the eye. I find this strategy to be more efficient for me and less invasive for my patients. Here, I explain the technique and why the CONSTELLATION® System is a good platform from which to perform it.

Figure 1. Removal of a dislocated IOL by raising it into the anterior chamber requires a large corneal limbal incision, which can be less than ideal for several reasons, including the risk of hypotony and longer healing time for the patient.

OLD VS. NEW TECHNIQUE

For patients, the dislocation of an IOL into the vitreous can be an unsettling turn of events. Vision disruption is often sudden and profound. Once the cataract surgeon refers a patient to me, if it has not already been done, I reassure him that his vision will be fine by having him look through a +10 lens. In general, unless a dislocated IOL has caused a retinal detachment,9 an IOL in the vitreous is not an emergency situation. Nevertheless, in the vast majority of cases, I schedule the procedure for my next surgical day.

Some vitreoretinal surgeons choose to implant a completely new IOL, reposition the dislocated IOL in the sulcus or use various suturing techniques to keep it in place. I prefer to simply remove the dislocated IOL and allow the cataract surgeon to choose the next step for each patient. In some cases, an IOL may not be stable in the sulcus, and if a lens was originally implanted in the capsular bag, sewing it in may not be the best solution either. One could make an argument that rather than simply removing a dislocated IOL, the vitreoretinal specialist should exchange or reposition the IOL to spare the patient an additional surgery at a later date. However, I've never had a patient upset with my approach and the cataract surgeons I work with like it as well.

In the past, I removed IOLs from the vitreous, using the technique that I, and most vitreoretinal surgeons, learned in training. I would perform a three-port vitrectomy, freeing the IOL from all of the vitreous gel enveloping it, raising the IOL into the anterior chamber, and making a beveled corneal limbal incision through which I would remove the IOL. One of the drawbacks to this technique was the need to use a corneal incision in addition to the three PPV sclerotomies. Often, it wasn't easy to create an ideal beveled wound because the cataract surgeon had already operated through that area, and with time, thinning and scarring of the limbus ensued. In addition, the corneal wound had to be relatively large and would have to be gaped to pull the IOL through, so hypotony was a frequent concern. It was a challenge, too, to get the IOL into the anterior segment and keep it there for the necessary maneuvers. Another drawback was dragging the IOL out of an anterior segment wound, which sometimes lead to iris prolapse, especially with light irides, or damage the corneal endothelium or Descemet's. Furthermore, it was often difficult to tightly close the corneal wound without several sutures and the resulting threat of a large amount of induced corneal astigmatism. While this method was effective and not usually technically difficult, I found it to be tedious and time-consuming because it required numerous incisions, sutures and intraocular maneuvers that were not part of my normal routine.

Figure 2. A thin strip of dislocated IOL, which had been segmented using Packer/Chang IOL Cutters, just prior to removal through the pars plana.

STEPS IN IOL REMOVAL

With my new method for removing posteriorly dislocated IOLs, I set up for a standard three-port 20-gauge vitrectomy with a chandelier light. As with the old method, it is important to accomplish a complete vitrectomy so the IOL is free of vitreous, especially near the sclerotomies. With the IOL free from vitreous and (usually) lying on the posterior pole, I enlarge the 10 o'clock sclerotomy (my right-hand side) to accommodate a pair of Packer/Chang IOL Cutters (MST, Redmond, Wash.). These microscissors are designed for cataract surgeons to use through the paracentesis and they have exceptional cutting ability. I use a handheld or fundus contact lens to help me see, so I can safely grasp the IOL with forceps, then I elevate the IOL into the mid-vitreous cavity. Next, using chandelier illumination and the BIOM® wide-angle viewing system (Insight Instruments), forceps in my left hand and the scissors in my right hand, I cut the IOL into several thin strips. When it is in sections, I use the same enlarged sclerotomy I used for the scissors to remove the pieces one at a time with forceps.

Initially, I was concerned that cutting the IOL in this manner would create jagged edges or cause the pieces to swirl around in the infusion currents, but they just fall gently back onto the posterior segment when cut. I am very happy with how the technique has worked in the cases I've done so far. One caveat worth mentioning: this procedure will not work with a polymethylmethacrylate (PMMA) lens — only silicone and acrylic lenses are flexible enough to be cut with scissors. Rigid PMMA lenses must be removed as a single unit, and this is most easily done through a limbal incision.

I follow the patients for approximately a month after the procedure, seeing them at 1 day, 1 week and 1 month after surgery to check for elevated IOP and other potential postoperative complications, such as cystoid macular edema and retinal detachment.6,10-11 I have experienced no complications to date, and, because the anterior segment has been manipulated much less and suturing is not as pronounced, patients have been more comfortable after surgery with this new method. All patients have been ready to return to the cataract surgeon following their 1-month visit with me.

TRUST IN YOUR TECHNOLOGY IS KEY

I like using the CONSTELLATION® Vision System for this new technique for several reasons. First, during manipulation of the IOL, it is important that pieces not “catch” onto any vitreous. With the ULTRAVIT® vitrectomy probe for the CONSTELLATION® System, I can cut at up to 5,000 cpm and also control the duty cycle for an efficient core vitrectomy, as well as minimize vitreoretinal traction in the periphery. These features enable an efficient vitrectomy, in some cases 4 to 5 minutes, which means I can seamlessly insert a dislocated IOL case into any part of any surgical day. While the new technique could also be performed with the ACCURUS® Surgical System or other state-of-the-art vitrectomy systems with chandelier lighting (to free up both hands for grasping and cutting), the Chandelier Lighting System available for the CONSTELLATION® System is brighter and has a broad illumination angle of 106º, providing excellent visualization for the necessary IOL manipulations described.

Managing a posteriorly dislocated IOL completely in the posterior segment allows me to reduce the risk of several intraoperative complications, work more efficiently in the area of the eye where I am most comfortable, and offer patients a more comfortable recovery period. This type of case also illustrates how today's vitreoretinal surgical technologies open the door for managing more types of cases with smaller-gauge instruments. I plan to remove my next dislocated IOL with the CONSTELLATION® System using a 23-gauge approach (provided that a 23-gauge forceps will hold the IOL steady enough for cutting). This will take the new technique another step forward, incorporating all of the benefits of microsurgery.

REFERENCES

1. Gimbel HV, Condon GP, Kohnen T, Olson RJ, Halkiadakis I. Late in-the-bag intraocular lens dislocation: incidence, prevention, and management. J Cataract Refract Surg 2005;31(11):2193-2204.
2. Mönestam EI. Incidence of dislocation of intraocular lenses and pseudophakodonesis 10 years after cataract surgery. Ophthalmology 2009;116(12):2315-2320.
3. Hayashi K, Hirata A, Hayashi H. Possible predisposing factors for in-the-bag and out-of-the-bag intraocular lens dislocation and outcomes of intraocular lens exchange surgery. Ophthalmology 2007;114(5):969-975.
4. Davis D, Brubaker J, Espandar L, et al. Late in-the-bag spontaneous intraocular lens dislocation: evaluation of 86 consecutive cases. Ophthalmology 2009;116(4):664-670.
5. Jakobsson G, Zetterberg M, Lundstro M, Stenevi U, Grenmark R, Sundelin K. Late dislocation of in-the-bag and out-of-the bag intraocular lenses: ocular and surgical characteristics and time to lens repositioning. J Cataract Refract Surg 2010;36(10):1637-1644.
6. Kim SS, Smiddy WE, Feuer W, Shi W. Management of dislocated intraocular lenses. Ophthalmology 2008;115(10):1699-1704.
7. Gross JG, Kokame GT, Weinberg DV. In-the-bag intraocular lens dislocation. Am J Ophthalmol 2004;137(4):630-635.
8. Seo MS, Kim CR, Nah HJ, et al. Management of posteriorly dislocated intraocular lens using pars plana vitrectomy. Korean J Ophthalmol 2000;14(2):80-84.
9. Campo RV, Chung KD, Oyakawa RT. Pars plana vitrectomy in the management of dislocated posterior chamber lenses. Am J Ophthalmol 1989;108(5):529-534.
10. Mello MO Jr, Scott IU, Smiddy WE, Flynn HW, Feuer W. Surgical management and outcomes of dislocated intraocular lenses. Ophthalmology 2000;107(1):62-67.
11. Sarrafizadeh R, Ruby AJ, Hassan TS, et al. A comparison of visual results and complications in eyes with posterior chamber intraocular lens dislocation treated with pars plana vitrectomy and lens repositioning or lens exchange. Ophthalmology 2001;108(1):82-89.


Dr. Solley specializes in the diagnosis and treatment of diseases of the retina and vitreous. He practices with Texas Retina Associates, which has 13 offices throughout the state.

Closing

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.

Disclosures

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