SEP 2012

EyeWorld is the official news magazine of the American Society of Cataract & Refractive Surgery.

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Page 43 of 103

September 2012 Uveitis continued from page 42 A variety of techniques have www.AcrySofIQTORIC.com CAUTION: Federal (USA) law restricts this device to the sale by or on the order of a physician. INDICATIONS: The AcrySof® IQ Toric posteri- or chamber intraocular lenses are intended for primary implantation in the capsular bag of the eye for visual correction of aphakia and pre-existing corneal astigmatism sec- ondary to removal of a cataractous lens in adult patients with or without presbyopia, who desire improved uncorrected distance vision, reduction of residual refractive cylin- der and increased spectacle independence for distance vision. WARNING/PRECAUTION: Careful preopera- tive evaluation and sound clinical judgment should be used by the surgeon to decide the risk/benefit ratio before implanting a lens in a patient with any of the conditions described in the Directions for Use label- ing. Toric IOLs should not be implanted if the posterior capsule is ruptured, if the zonules are damaged, or if a primary pos- terior capsulotomy is planned. Rotation can reduce astigmatic correction; if necessary lens repositioning should occur as early as possible prior to lens encapsulation. All viscoelastics should be removed from both the anterior and posterior sides of the lens; residual viscoelastics may allow the lens to rotate. Optical theory suggests that high astigmatic patients (i.e. > 2.5 D) may experience spa- tial distortions. Possible toric IOL related factors may include residual cylindrical er- ror or axis misalignments. Prior to surgery, physicians should provide prospective pa- tients with a copy of the Patient Informa- tion Brochure available from Alcon for this product informing them of possible risks and benefits associated with the AcrySof® IQ Toric Cylinder Power IOLs. Studies have shown that color vision dis- crimination is not adversely affected in in- dividuals with the AcrySof® Natural IOL and normal color vision. The effect on vision of the AcrySof® Natural IOL in subjects with hereditary color vision defects and acquired color vision defects secondary to ocular disease (e.g., glaucoma, diabetic retinopa- thy, chronic uveitis, and other retinal or op- tic nerve diseases) has not been studied. Do not resterilize; do not store over 45° C; use only sterile irrigating solutions such as BSS® or BSS PLUS® gating Solutions. ATTENTION: Reference the Directions for Use labeling for a complete listing of indica- tions, warnings and precautions. Sterile Intraocular Irri- been described for dealing with small pupils and posterior synechiae, including viscodissection, iris hooks, and pupil maintainers. Remember that trypan blue, which is often invaluable in dealing with uveitic cataracts, will only stain the exposed anterior capsule, so adequate dilation must be obtained prior to staining, whether it is done as a straight injection, under air, or under viscoelastic. Once this step has been achieved and a continuous capsulorhexis performed, the cataract can be removed using what- ever technique the surgeon prefers. Complete hydrodissection is essen- tial. Although uveitic cataracts can be quite dense, more often they are relatively soft (because they are more common in younger patients) and are removed with small amounts of phacoemulsification energy. Glaucoma is common in patients with uveitis and cataracts for a variety of reasons: the use of corticosteroids, outflow compromise from peripheral anterior synechiae, lens-induced mechanisms (phaco- morphic glaucoma from tumescent crystalline lenses, IOL chafing, and pupillary block), or retained lens fragments. Progressive iridocapsular adhesions ("zippering up" of the pupil) are a sign of incomplete uveitis control, and cycloplegic therapy should be added. However, laser peripheral iridotomy (LPI) is usually unnecessary and may actu- ally worsen posterior synechiae for- mation. Flow of aqueous through the pupil is diminished once the LPI has been performed, and the altered flow dynamics cause progressive pupillary block. If the LPI subse- quently closes, as is common in eyes with uveitis, acute pupillary block glaucoma can then occur. Focal edema of the peripheral cornea may indicate a retained lens fragment; goniosocopy is essential for detection. Surgical removal is usually simple and curative. Combined phacoemulsification and either trabeculectomy or tube shunt surgery should be considered in pa- tients with uveitic cataracts and un- controlled glaucoma. If secondary glaucoma occurs after cataract surgery, corticosteroids should be tapered to the lowest effective dose or discontinued altogether if possi- ble; steroid-sparing immunomodula- tory therapy such as methotrexate, mycophenolate, or tumor necrosis factor antagonists may be necessary, particularly in children. Medical management should start with topical beta blockers or carbonic anhydrase inhibitors because of the potential risk of CME from adrener- gic agents or worsening of uveitis from prostaglandin analogs. How- ever, these risks are small, and at least a trial of adding such drugs may be preferable to surgical inter- vention in some patients. Glaucoma surgery has a higher failure rate in patients with uveitis. As with cataract surgery, filtration surgery should be undertaken only after the uveitis has been completely con- trolled, if possible. Remember that computerized visual field tests may be difficult to interpret in these pa- tients because of CME or epiretinal membrane. Small pigmented deposits on the IOL surface are not necessarily worrisome, but larger deposits re- sembling giant cells (Figure 1) are usually a sign of persistent uveitis, even if no inflammatory cells in the aqueous are detected. The deposits have been histopathologically to comprise fibroblast-like and foreign body giant cells.3 Sometimes such deposits will coalesce into a fine anterior pupil- lary membrane that compromises vision and requires low-power YAG membranotomy. However, it remains necessary to control the uveitis and eliminate reversible causes of the uveitis. If the IOL is in the sulcus or has asymmetric capsu- lar bag/sulcus fixation and the uveitis cannot be controlled easily, consideration should be given to removal of the IOL, allowing the eye to recover, and then consider a secondary IOL at a later date. Obvi- ously, the status of the other eye is critical in determining the best approach in any given situation. Case 1 A 32-year-old Caucasian woman with unilateral, recurrent granulo- matous uveitis of the left eye with a negative workup developed CME that responded to repeated periocu- lar injections of triamcinolone acetonide (Figure 2). However, she developed cataract and steroid-in- duced glaucoma with IOP as high as 46 mm Hg that responded to med- ical management. When her cataract became visually significant, she un- derwent combined phacoemulsifica- tion/PC IOL and anti-metabolite trabeculectomy. She recovered 20/20 vision and excellent IOP control without medication. She continued to have intermittent attacks of unilateral uveitis and CME, but tolerated periocular corticosteroid injections without pressure spikes. During follow-up, she developed mild, asymptomatic uveitis in the right eye with peripheral mutton-fat keratic precipitates. On further ques- tioning, she described the recent onset of a skin lesion on her finger that had been biopsied, revealing noncaseating granulomata consis- tent with sarcoidosis. Case 2 A 36-year-old man with acute, recurrent HLA B27-associated anterior uveitis in both eyes devel- oped iris bombe from extensive posterior synechiae in the left eye (Figure 3A). There were extensive pigment deposits on the anterior lens surface (Figure 3B). Aggressive control of the uveitis followed by synechiolysis with phacoemulsifica- tion and PC IOL placement resulted in resolution of the iris bombe and excellent vision (Figure 3C). EW References 1. Foster CS, Fong LP, Singh G. Cataract surgery and intraocular lens implantation in patients with uveitis. Ophthalmology 1989;96:281-88. 2. Sheppard JD, Nguyen GD, Usner DW, Comstock TL. Clin Ophthalmol 2012;6:79-85. 3. Ohara K. Biomicroscopy of surface deposits resembling foreign-body giant cells on implanted intraocular lenses. Am J Ophthalmol 1985;99:304-11. Editors' note: Dr. Dunn is associate professor of ophthalmology, Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore. He has no financial interests related to this article. Contact information Dunn: 410-955-1966, jpdunn@jhmi.edu © 2011 Novartis 12/11 TOR12421PI

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