Objective To compare the corneal parameters of the two eyes in a myopia population and to establish the normal range of interocular differences for clinical examination and diagnosis. Methods In this cross-sectional study, 210 patients (420 eyes) whose mean age was 24.8±0.4 years, average spherical equivalents were -4.96±0.14 D in right eyes and -4.94±0.14 D in left eyes, were measured by Pentacam. Corneal parameters, including mean keratometry Km, central corneal thickness (CCT), thinnest corneal thickness (TCT), the location of the thinnest points (X, Y) and the distance from the thinnest to central corneal points (√(x²+y²)) and the interocular differences were recorded. A paired t test was used to assess the differences between the two eyes′ corneal parameters and a Pearson correlation was used to describe their linear relationship. The normal range of interocular differences was described by the 95th percentile or mean+2 standard deviation (SD). Results No statistically significant binocular differences were found in Km (t=-1.38,P>0.05), CCT (t=1.44, P>0.05), TCT (t=1.25, P>0.05), √(x²+y²) (t=1.87, P>0.05) except X (t=-33.92, P<0.01) and Y (t=8.95, P<0.01). Less than 5% of the sample had differences greater than 0.5 D in Km, 13.67 μm in CCT, 12.83 μm in TCT, 1.52 mm in the vertical location of the thinnest points, 0.32 mm in the horizontal location of the thinnest points, or 0.30 mm in the distance from the thinnest to central corneal points between eyes. Conclusion Binocular corneal parameters have some differences. The normal range of binocular differences can provide a guide for intraocular lens power calculation, clinical diagnosis and screening of glaucoma and corneal ectasia disease.
谭维娜,华焱军,潘超,陈佳,王勤美. 近视人群双眼角膜参数的差异[J]. 中华眼视光学与视觉科学杂志, 2013, 15(4): 222-225.
TAN Wei-na,HUA Yan-jun,PAN Chao,CHEN Jia,WANG Qin-mei. Interocular asymmetry of corneal parameters in a population of myopes. Chinese Journal of Optometry Ophthalmology and Visual Science, 2013, 15(4): 222-225. DOI: 10.3760/cma.j.issn.1674-845X.2013.04.008
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