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Reliability of Measurements of Back Vertex Power for Soft Contact Lenses Using an Auto-Lensmeter  

Kim, Kun-Kyu (Department of Visual Optics, Kyungwoon University)
Lee, Wook-Jin (Department of Visual Optics, Kyungwoon University)
Lee, Sun-Haeng (Department of Ophthalmic Optics, Gimhae College)
Kwak, Ho-Won (Department of Visual Optics, Kyungwoon University)
Yu, Dong-Sik (Department of Visual Optics, Kyungwoon University)
Publication Information
Journal of Korean Ophthalmic Optics Society / v.15, no.1, 2010 , pp. 39-46 More about this Journal
Abstract
Purpose: To assess the reliability for measuring the back vertex power of soft contact lenses by dry blotting and wet cell method using an auto-lensmeter. Methods: The soft contact lenses used for measurement were 5 types that were distributed in Korea, and 4 back vertex powers (-1.50D, -3.00D, -6.00D, -9.00D) were used. and repeatability and reproducibility were evaluated by measuring them with an auto-lensmeter by two examiners. Results: Measured powers by dry blotting method were ranged in mean differences from 0.03D to 0.18D for overall lenses, 0.10D to 0.18D for silicone hydrogel lenses, 0.03D to 0.08D for hydrogel lenses. The mean differences between two examiners were less than 0.10D, and the inter-examiner reproducibility was good for dry blotting method. The mean difference between powers determined by wet cell method were 0.09D to 0.69D, the mean differences between two examiners were 0.02D to 0.59D. The reliability of measurements and inter-examiner reproducibility were less than dry blotting method. Conclusions: The reliability of measurements for all materials was better in dry blotting than wet cell method, the re liability of measurements for silicone hydrogel lenses was low in both methods. In clinical practical which requires quick checking of back vertex power using an auto-lensmeter. dry blotting method is thought to be more efficient than wet cell one.
Keywords
Soft contact lens; Back vertex power; Dry blotting; Wet cell; Reliability; Auto-lensmeter;
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