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http://dx.doi.org/10.14479/jkoos.2015.20.3.349

Changes of Corrective Astigmatism Values Depending on Position of Circle of Least Confusion in Astigmatic Refining Test Using Cross Cylinder  

Kim, Sang-Yeob (Dept. of Optometry, Kangwon National University)
Lee, Min Jae (Dept. of Optometry, Kangwon National University)
Lee, Kang Cheon (Dept. of Optometry, Kangwon National University)
Lee, Tae Hui (Dept. of Medical Health Science, Graduate School, Kangwon National University)
Moon, Byeong-Yeon (Dept. of Optometry, Kangwon National University)
Cho, Hyun Gug (Dept. of Optometry, Kangwon National University)
Publication Information
Journal of Korean Ophthalmic Optics Society / v.20, no.3, 2015 , pp. 349-354 More about this Journal
Abstract
Purpose: To investigate the changes of corrective values of astigmatism caused by the position of circle of least confusion on retina in refining astigmatic test using cross cylinder. Methods: 62 subjects (115 eyes) aged $22.24{\pm}2.48$ years participated for this study. After astigmatic test using a radial chart, refining test was performed using a cross cylinder in a condition of maximum plus to maximum visual acuity (MPMVA). Astigmatic refining test was repeatedly performed in each condition of which S+0.75 D, S+0.50 D, S+0.25 D, S-0.25 D, S-0.50 D, and S-0.75 D are added to spherical lenses of MPMVA. The measured values were compared with the values in MPMVA condition. Results: As compared with values in condition of MPMVA, change of astigmatic axis was increased with add the power of (+) spherical lenses and (-) spherical lenses. In same spherical condition, change of astigmatic axis was decreased with increment of astigmatic power (p<0.05). The corrective power of astigmatism was reduced with increment of (+) spherical lenses (p<0.05), and was raised with increment of (-) spherical lenses compared with the power in MPMVA condition. In case of adding (+) spherical lenses, difference of astigmatic power increased with increment of corrective astigmatism power in same test condition. Conclusions: In order to obtain a proper values for corrective astigmatism, position of circle of least confusion should be accurately adjusted before the performing an astigmatism's refining test.
Keywords
Cross cylinder; Refining test for astigmatism; Position of circle of least confusion; Corrective astigmatism axis; Corrective astigmatism power;
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Times Cited By KSCI : 1  (Citation Analysis)
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