Correction of Residual Hyperopia After Cataract Surgery ... - Iogen

An important aspect of 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 of built in UV protection in the absence of
sunglasses (Chang SH, unpublished data, 2006), but after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. After lockin,
no UV protection is necessary.
While this study demonstrates precise adjustment of
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 of 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 of 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 of 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 of 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 of Calhoun
Vision with financial interest. Involved in design of study (A.C., C.S., S.C., B.T., P.R., D.S.); conduct of study (A.C.); collection, management, analysis
and interpretation of the data (A.C., C.S., S.C., P.R., B.T., D.S.); preparation of the manuscript (A.C., S.C., D.S.); and review or approval of the
manuscript (A.C., C.S., S.C., B.T., P.R., D.S.). The clinical trial was approved and registered with Ministry of 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 of Helsinki and all patients gave written informed consent for research.
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