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EW CATARACT 35 September 2014 rifabutin). However, long-term use of the medication was reported, and the discoloration occurred late postoperatively. 3. Opacification/discoloration of silicone lenses has also been described in relation to deposition of material on the lens surfaces, which is different from the total and homogeneous opacification of the optic component described here. Cases included coating of the lenses with silicone oil in patients with previous vitreoreti- nal procedures and coating with ophthalmic ointment that could penetrate the anterior chamber postoperatively in small incision procedures. 4. There have also been reports on calcification, with formation of calcified deposits on the posterior surface of silicone lenses. How- ever, this has only been observed in eyes with associated asteroid hyalosis. EW References 1. Hilgert CR, Hilgert A, Höfling-Lima AL, Farah ME, Werner L. Early opacification of SI-40NB silicone intraocular lenses. J Cataract Refract Surg 2004;30(10):2225–9. 2. Werner L, Dornelles F, Hilgert CR, Botelho F, Conte PF, Rozot P, Andrenyak DM, Mamalis N, Olson RJ. Early opacification of silicone intraocular lenses: Laboratory analyses of the surface of the silicone IOL, rendering the lens less hydrophobic and increasing the permeability of the lens to water, causing opacifi- cation. Three-piece silicone IOLs with PMMA haptics require ster- ilization by techniques using low temperature and pressure. Therefore, ethylene oxide gas sterilization is used, and the lenses are packaged in semi-permeable packages to allow the gas to enter. One must assume that other chemical vapors may also penetrate the package and contam- inate the lenses. The importance of appropriate conditions for steriliza- tion and storage of IOL packages is critical to maintain the integrity of the lens material. A general measure that should be implemented is to keep all IOLs in a clean, dry envi- ronment at room temperature, and protected from potentially harmful sprays. Differential diagnosis 8 1. In the early 1990s, there were reports of discoloration of silicone lenses linked to the manufactur- ing process and incomplete ex- traction of large residual polymers. However, this generally occurred later postoperatively (weeks to months). 2. There have been cases of brown or rose discoloration of silicone lens- es, associated with use of systemic medications (e.g., amiodarone, This case differs from the previously reported cases of optic opacification in that a homogenous gray opacification was observed on the first postoperative day. Tanaka et al 7 reported a similar case in which a persistent brown opacification was observed 1 day after implantation in a patient who had the same IOL design implanted (SI-40NB). The investigators also concluded that this phenomenon was secondary to influx of water within the lens, though no further analyses of the surface composition was conducted. A thorough review of the his- tory of the silicone IOL described in this case and the other lenses explanted in Brazil was conducted by the manufacturer. According to an internal Abbott Medical Optics (AMO) materials research report (March 26, 2004), the storage lot, which contained the IOLs prior to use in surgery, was sprayed with cleaning and insecticide agents. Exogenous molecules were noted in GC/MS analysis of the explanted IOLs, and some of them are also commonly found in insecticides and cleaning solutions. Given the storage information obtained from AMO and the presence of exoge- nous compounds detected during GC/MS analysis, we hypothesize that chemical contamination of the lens occurred preoperatively. This may have changed the composition Figure 1: Clinical photograph of an eye implanted with a 3-piece silicone lens, exhibiting optic opacification on the first postoperative day. Figure 2: Gross photograph of the explanted silicone IOL from the patient described in this case report. The degree of opacification can be seen in the hydrated state (left half) and compared to the transparency evident in the dry state (right half). Source (all): Liliana Werner, MD, PhD of six explants. J Cataract Refract Surg 2006;32(3):499–509. 3. Watt RH. Discoloration of a silicone intraocular lens 6 weeks after surgery. Arch Ophthalmol 1991;109(11):1494–5. 4. Milauskas AT. Silicone intraocular lens implant discoloration in humans. Arch Ophthalmol 1991;109(7):913–5. 5. Koch DD, Heit LE. Discoloration of silicone intraocular lenses. Arch Ophthalmol 1992;110(3):319–20. 6. Kershner RM. In reply to Milauskas AT. Silicone intraocular lens implant discolor- ation in humans [letter]. Arch Ophthalmol 1991;109(7):913–4. 7. Tanaka T, Saika S, Hashizume N, Ohnishi Y. Brown haze in an Allergan SI-40NB silicone intraocular lens. J Cataract Refract Surg 2004;30(1):250–2. 8. Werner L. Causes of intraocular lens opacification or discoloration. J Cataract Refract Surg 2007;33(4):713–26. Editors' note: Drs. Farukhi, Werner, and Mamalis are affiliated with the John A. Moran Eye Center, University of Utah, Salt Lake City. They have no financial interests related to this article. Contact information Farukhi: aabid.farukhi@hsc.utah.edu Mamalis: nick.mamalis@hsc.utah.edu Werner: liliana.werner@hsc.utah.edu

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