Eyeworld

EW NEWS & OPINION 14 I nadequate capsule support is a rare but potential com plication associated with cataract sur- gery. It may lead to malposi- tioning of the posterior chamber IOL and potential recurrent subluxation. Treatment options in - clude leaving the patient aphakic, placing an anterior chamber (ACIOL), or suture-fixating a three- piece foldable acrylic IOL in the cil- iary sulcus or the peripheral iris. Aphakia may increase the risk of glaucoma and render the patient de- pendent on contact lenses for good visual acuity. ACIOL may lead to en- dothelial cell loss and pseudophakic bullous keratopathy. A posteriorly placed IOL with suturing to the cil- iary sulcus can be skill- and time-de- manding. Suturing the IOL to the peripheral iris using a modified Mc- Cannel technique has been shown to be safe, effective, and efficient. 1-3 We present a step-by-step approach to this technique. We avoid pharma- cological dilatation of the pupil but instead cause dilation with retrobul- bar injection. Initially, if the subluxed lens is a one-piece lens, it will have to be re- moved. A three-piece IOL can often be repositioned and suture fixated as described below. A 3.5-mm clear corneal incision is created. Viscoelas- tic material is injected into the AC to help protect the corneal endothe- lial cells. The subluxed IOL is brought to the AC. With a Barraquer sweep and IOL inserter, the IOL is folded and removed from the eye. Alternative methods may include cutting the IOL and removing the pieces individually. If there is vitre- ous prolapse, a core anterior or pars plana vitrectomy may be performed. The pupil is constricted with acetylcholine to facilitate pupillary capture of the IOL optic. Viscoelastic material is injected to deepen the AC. The IOL is folded in a "mous- tache" fold and inserted through the corneal wound (Figures 1a-1b). Care must be taken not to bend or break the trailing haptic in this process. To do so, the advancing haptic may need to be individually inserted with the help of insertion forceps. The haptics should be placed posterior to the iris and within the sulcus, with the optic above the plane of the iris (Figure 1c). A Barraquer sweep is passed through the paracentesis and placed beneath the optic as the lens is unfolded to ensure pupillary cap- ture (Figures 1d-1f). Additional vis- coelastic material is injected into the AC. The optic is then elevated with the Barraquer sweep so that the haptics contour is visualized through the iris, simplifying passage of the sutures. Using a modified McCannel-type iris fixation tech- nique, a 10-0 polypropylene suture is passed on a needle through clear cor nea and the iris, under the pe- ripheral aspect of the first haptic, then out through the iris and clear cornea (Figure 2). A paracentesis is created over the first haptic, and the two ends of the suture are pulled through this site (Figure 3). The sec- ond haptic is secured in a similar manner, making sure the sutures are 180 degrees apart. The sutures are tied with a locking 2-1-1 throw (Figure 4). The optic is placed poste- rior to the iris. If there is enough posterior capsular support, using a Sinskey hook the iris is manipulated to produce a round pupil (Figure 5). The retained viscoelastic material is removed from the AC. Acetylcholine chloride is injected again to ensure a round miotic pupil (Figure 6). Air is injected into the AC and checked for uniden tified strands of vitreous. If vitreous is present, a Bar raquer sweep is used to break the strands or a more extensive pars plana vitrectomy is performed. Then a repeat injec tion of air is made into the AC, again inspecting for vitre- ous. Balanced salt solution is in- jected into the AC, bringing the eye to physiologic pressure. A 10-0 nylon suture is used to close the main corneal wound. The wounds are tested for leaks. This technique permits the sur- geon to properly treat patients who develop loss of capsule sup port at the time of cataract surgery and fa- cili tates the management of IOL problems after surgery that require IOL exchange. It also allows second- December 2011 by Yassine Daoud, M.D., and Walter J. Stark, M.D. Iris-fixated surgical technique of an acrylic intraocular lens in the absence of capsule support A phakia can be corrected with the use of anterior chamber lenses and iris fixation or scleral fixation of posterior chamber lenses. I still per- form all three modes of secondary IOL implantation and have found that each has its own inherent advantages and disadvantages. Iris fixation is especially useful in the clinical scenario of symp- tomatic subluxed three-piece posterior chamber IOLs. Whether fixated with a modified McCannel suture or a Siepser slipknot, the fixation process is rela- tively quick without the extensive tissue dissection of scleral fixation and main- tains the advantages of a posterior chamber IOL. In this month's column, Drs. Daoud and Stark describe their technique for iris fixation of secondary foldable posterior chamber IOLs. The figures for their article are beautiful and the description of their technique clear and concise. As is the case for most of the articles in this column, the pages should be torn out and saved for future reference. Richard Hoffman, M.D., tools and techniques editor Or view the video at www.eyeworld.org/ replay.php. Watch this video on your smartphone or iPad using your QR code reader. (Scanner available for free at your app store.) Tools and techniques Figures 1a and 1b Figure 1c Figures 1d, 1e, and 1f continued on page 16

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