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http://dx.doi.org/10.14479/jkoos.2016.21.3.259

Cause Analysis in Decrease of Body Stability According to The Induced Astigmatic Blur  

Kim, Sang-Yeob (Dept. of Optometry, Kangwon National University)
Yu, Dong-Sik (Dept. of Optometry, 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.21, no.3, 2016 , pp. 259-264 More about this Journal
Abstract
Purpose: To establish the cause of decrease in body stability and to analyze the effects on sensory organs maintaining static balance according to the induced astigmatic blur. Methods: Twenty subjects (10 males, 10 females; mean age, $23.40{\pm}2.70years$) were participated in this study. To induce myopic simple astigmatism, the axis directions of cylindrical lenses were placed $180^{\circ}$ on both eyes (with-the-rule), $90^{\circ}$ on both eyes (against-the-rule), and $45^{\circ}$ on both eyes (oblique). Cylindrical lenses of +0.50, +1.00, +1.50, +2.00, +3.00, +4.00, and +5.00 D were used to increase astigmatic blur in each astigmatism types. General stability (ST) and sway power (SP) in frequencies by each sensory organs were analyzed using the TETRAX biofeedback system. Results: ST in the all astigmatism types were raised with increase of astigmatic blur compared to full corrected condition, but a significant difference only showed in the induced oblique astigmatism. According to the results of correlation analysis between ST and SP in the each frequencies with increase of astigmatic blur, the causes of increased ST in the induced oblique astigmatism showed to have a high correlation in order of somatosensory system (high-medium frequency), central nervous system (high frequency), peripheral vestibular system (low-medium frequency), and visual system (low frequency). Conclusions: The visual information by uncorrected oblique astigmatism may disturb the normal functions of all sensory organs maintaining body balance, consequently, the body stability can be reduced. Therefore, optimal correction of astigmatism can play an important role for reducing the instability of body balance.
Keywords
Astigmatic blur; Oblique astigmatism; Sensory organs; Body stability; General stability; Sway power;
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Times Cited By KSCI : 3  (Citation Analysis)
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