Wiffen S J, Hodge D O, Bourne W M
Department of Ophthalmology, Mayo Clinic and Mayo Foundation, Rochester, Minnesota 55905, USA.
Cornea. 2000 Jan;19(1):47-51. doi: 10.1097/00003226-200001000-00010.
To compare central and peripheral corneal endothelial cell morphometry in normal subjects and long-term contact lens wearers.
Endothelial cell density (ECD), coefficient of variation of cell area (CV), and percentage of six-sided cells were measured by contact specular microscopy in the corneal center and temporal periphery of both eyes of 43 long-term contact lens wearers and in 84 normal subjects who had never worn contact lenses. The latter group included 43 age- and sex-matched controls for the contact lens wearers. ECDs were corrected for magnification changes due to corneal thickness.
Central ECD (2,723+/-366 cells/mm2, mean +/- SD) was significantly higher than peripheral ECD (2,646+/-394 cells/mm2) for the normal group (p = 0.01) but not for the contact lens wear group (2,855+/-428 cells/mm2 central, 2,844+/-494 cells/mm2 peripheral, p = 0.84). Peripheral CV was significantly higher than central for normal subjects and contact lens wearers and was significantly higher in both center and periphery in contact lens wearers than in controls. Central percentage of six-sided cells was significantly higher than peripheral for normal subjects and contact lens wearers and was lower in both center and periphery in contact lens wearers than in controls.
Central ECD was significantly higher by 3% than peripheral ECD in normal subjects, but not in contact lens wearers. The results suggest that contact lens wear causes a mild redistribution of endothelial cells from the central to the peripheral cornea. A reversal of this redistribution after contact lens wear is discontinued for refractive surgery could mask mild central endothelial damage from the refractive procedure.
比较正常受试者和长期佩戴隐形眼镜者角膜中央和周边内皮细胞形态学特征。
采用接触式镜面显微镜测量43名长期佩戴隐形眼镜者及84名从未佩戴过隐形眼镜的正常受试者双眼角膜中央和颞侧周边的内皮细胞密度（ECD）、细胞面积变异系数（CV）以及六边形细胞百分比。后一组包括43名年龄和性别与隐形眼镜佩戴者匹配的对照者。对ECD进行校正，以消除因角膜厚度导致放大倍数变化的影响。
正常组中央ECD（2723±366个细胞/mm²，平均值±标准差）显著高于周边ECD（2646±394个细胞/mm²）（p = 0.01），但隐形眼镜佩戴组并非如此（中央2855±428个细胞/mm²，周边2844±494个细胞/mm²，p = 0.84）。正常受试者和隐形眼镜佩戴者的周边CV均显著高于中央，且隐形眼镜佩戴者中央和周边的CV均显著高于对照组。正常受试者和隐形眼镜佩戴者中央六边形细胞百分比均显著高于周边，且隐形眼镜佩戴者中央和周边的六边形细胞百分比均低于对照组。
正常受试者中央ECD比周边ECD显著高3%，但隐形眼镜佩戴者并非如此。结果表明，佩戴隐形眼镜会导致内皮细胞从角膜中央向周边轻度重新分布。屈光手术前停止佩戴隐形眼镜后这种重新分布的逆转可能会掩盖屈光手术造成的轻度中央内皮损伤。
