An important aspect <strong>of</strong> the light adjustable lens is the need to wear UV protective spectacles until lock-in is performed. This is because the photoreactive silicone macromer undergoes photopolymerization when exposed to UV light. The light adjustable lens has approximately one hour <strong>of</strong> built in UV protection in the absence <strong>of</strong> sunglasses (Chang SH, unpublished data, 2006), but after that, there is a risk for photopolymerization and optical changes. Therefore, patients are instructed to wear the UV blocking sunglasses until lock-in is completed. <strong>After</strong> lockin, no UV protection is necessary. While this study demonstrates precise adjustment <strong>of</strong> hyperopia between 0.25 to 2.0 D, the eye would require a second adjustment to correct more than 2.0 D before lock-in. Chemical analysis <strong>of</strong> light adjustable lenses reveals that photoreactive macromer is available to undergo multiple photo-polymerization leading to additional refractive change as long as the lens is not locked-in. In vitro studies have achieved a 3.5 D power change with secondary adjustments <strong>of</strong> light adjustable lenses. The light adjustable lens and digital light device provide surgeons a means to fine tune refractive power in the postoperative period. In this small pilot series <strong>of</strong> patients treated for residual hyperopia, adjustments were precise and stable for up to six months follow-up. This technology may provide greater confidence in final refractive outcome as increasing numbers <strong>of</strong> corneal refractive surgery patients age and develop cataracts. THIS STUDY WAS SUPPORTED BY SMALL BUSINESS INNOVATIVE RESEARCH GRANT NO. EY12181-02. DRS SANDSTEDT, CHANG, Rhee, and Tsuchiyama are Calhoun Vision employees. Dr Chayet is a clinical investigator for Calhoun Vision. Dr Schwartz is the founder <strong>of</strong> Calhoun Vision with financial interest. Involved in design <strong>of</strong> study (A.C., C.S., S.C., B.T., P.R., D.S.); conduct <strong>of</strong> study (A.C.); collection, management, analysis and interpretation <strong>of</strong> the data (A.C., C.S., S.C., P.R., B.T., D.S.); preparation <strong>of</strong> the manuscript (A.C., S.C., D.S.); and review or approval <strong>of</strong> the manuscript (A.C., C.S., S.C., B.T., P.R., D.S.). The clinical trial was approved and registered with Ministry <strong>of</strong> Health, the Secretaria de Salud, No. 204/004209, in Mexico City, Mexico. The studies were approved by Codet Vision Institute Institutional Review Board, Comite De Investigacion y Etica, in Tijuan, Mexico. The study was performed in accordance with the Declaration <strong>of</strong> Helsinki and all patients gave written informed consent for research. REFERENCES 1. 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Olson R, Mamalis N, Hauge B. A light adjustable lens with injectable optics. Ophthalmol Clin North Am 2006;19:135– 142. 18. Hayashi K, Hayashi H. Comparison <strong>of</strong> the stability <strong>of</strong> 1-piece and 3-piece acrylic intraocular lenses in the lens capsule. J <strong>Cataract</strong> Refract Surg 2005;31:337–342. 19. ANSI Z80.11-2007, American National Standard for Ophthalmics – Laser Systems for Corneal Reshaping. VOL. 147, NO. 3 PSEUDOPHAKIC HYPEROPIA CORRECTION 397
Biosketch Artura Chayet, MD, is the Director <strong>of</strong> Codet Vision Institute, in Tijuana, Mexico and a Past-President <strong>of</strong> the Mexican Society <strong>of</strong> Refractive <strong>Surgery</strong>. He received his degree in Cornea and Refractive <strong>Surgery</strong> at the University <strong>of</strong> California, San Diego, California. Dr Chayet has become one <strong>of</strong> the world’s leading refractive surgeons. He has been recognized worldwide for contributing to the development <strong>of</strong> instruments, techniques, and s<strong>of</strong>tware used in refractive surgery today. 397.e1 AMERICAN JOURNAL OF OPHTHALMOLOGY MARCH 2009
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