Objective To observe the orientation of dynamically stabilized toric soft contact lenses (TCL) in Chinese subjects and discuss the effect of myopic refractive error, the amount of astigmatism and its axis. Methods This was a prospective clinical study. One hundred and ninety one subjects were fitted with dynamically stabilized TCLs. Subjects were classified into different groups based on the amount of sphere, cylinder and cylinder axis. The amount of rotation and stability of the lenses in the right eye was recorded and their relationship with myopic refractive error, astigmatic amount and axis were analyzed. Data were analyzed with ANOVA, Fisher′s exact test and Wilcoxon signed-rank test. Results There was no difference between corrected visual acuity of the dynamically stabilized TCLs and that of spectacles (Z=-1.061, P>0.05). The lenses had good centralized positioning and mobility. Lenses on eyes with non-oblique and greater amounts of astigmatism became relatively stable within a shorter time. Lenses in the high myopia group had better stability compared with the moderate myopia group (χ2=5.371, P<0.05). The amount of rotation was higher in the oblique astigmatism group than in with-the-rule and against-the-rule astigmatism groups (χ2=7.046, P<0.05; χ2=6.462, P<0.05). The higher the astigmatism, the better the stability and the less amount of lens rotation. Conclusion Spherical refractive error, amount of astigmatism and axis affect the orientation of dynamically stabilized TCLs to some extent. People with high myopia and against-the-rule astigmatism were the ideal subjects for fitting dynamically stabilized TCLs.
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