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Changes of Corrective Astigmatism Values Depending on Position of Circle of Least Confusion in Astigmatic Refining Test Using Cross Cylinder
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 Title & Authors
Changes of Corrective Astigmatism Values Depending on Position of Circle of Least Confusion in Astigmatic Refining Test Using Cross Cylinder
Kim, Sang-Yeob; Lee, Min Jae; Lee, Kang Cheon; Lee, Tae Hui; Moon, Byeong-Yeon; Cho, Hyun Gug;
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 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 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;
 Language
Korean
 Cited by
1.
근시성 난시안에서 난시축 변화가 시력에 미치는 영향,최준규;김보연;이은희;

디지털융복합연구, 2015. vol.13. 12, pp.285-290 crossref(new window)
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