长期配戴硬性透气性角膜接触镜对不同程度圆锥角膜的矫正效果及安全性评价

Efficacy and safety of long-term wearing rigid gas permeable contact lens in different degrees of keratoconus eyes

目的观察不同程度原发性圆锥角膜患者配戴硬性透气性角膜接触镜（RGPCL）5年以上的矫正效果、角膜曲率进展以及长期配戴的安全性。 方法采用回顾性病例观察研究方法，对2000—2010年在北京同仁医院配戴RGPCL超过5年的原发性圆锥角膜患者126例217眼的病例资料进行分析，依据角膜曲率Ks将圆锥角膜患者分为轻度、中度和重度组，角膜曲率Ks≤45.0 D者为轻度圆锥角膜组，Ks≥52.0 D者为重度圆锥角膜组，Ks介于二者之间者为中度圆锥角膜组。患者在初次就诊（戴镜前）及每次复查时均行LogMAR视力、自动验光仪/角膜曲率仪、裂隙灯显微镜及角膜地形图检查。评估RGPCL镜片配适状态，比较各组患者配戴框架眼镜矫正视力（SCVA）及RGP矫正视力（RGPVA），以及RGPCL配戴前后角膜表面参数变化和并发症情况。 结果轻度圆锥角膜组、中度圆锥角膜组和重度圆锥角膜组患者戴镜后末次随访的RGPVA分别为0.09±0.17、0.05±0.07和0.07±0.07，差异有统计学意义（F＝0.522，P＝0.594）；3个组患眼戴镜后末次随访时ΔKs分别为（2.25±5.42）、（0.26±3.44）和（－4.52±3.44）D，ΔKf分别为（2.06±4.98）、（1.02±3.41）和（－2.03±5.05）D，角膜散光变化值分别为（0.19±2.87）、（－0.78±2.84）和（－2.44±3.77）D，重度圆锥角膜组患者戴镜后末次随访时角膜曲率和角膜散光值的进展最小，差异均有统计学意义（均P〈0.05）。轻度圆锥角膜组、中度圆锥角膜组和重度圆锥角膜组患眼不同区域指数变化值（ΔDSI）分别为－0.33±1.64、0.14±3.01和－2.11±4.28，中央/周围指数变化值（ΔCSI）分别为－0.41±1.07、0.03±2.22和－2.49±4.15，角膜屈折力标准偏差变化值（ΔSDP）分别为－0.43±0.64、－0.02±0.89和－1.67±1.68，圆锥角膜预测指数变化值（ΔKPI）分别为0.00±0.07、0.03±0.09和－0.05±0.11，重度圆锥角膜组患者戴镜后末次随访时角膜表面参数值降低幅度均大于轻度圆锥角膜组和中度圆锥角膜组，差异均有统计学意义（均P〈0.01）。随访期间12眼出现轻度的结膜炎症状和点状角膜上皮荧光素染色，占5.5%。 结论RGPCL长期配戴可改善圆锥角膜患者视力并延缓角膜曲率的增加，且不增加角膜感染的风险，对于不同程度圆锥角膜的矫正是安全有效的。

ObjectiveTo evaluate the efficacy, safety of rigid gas permeable contact lens （RGPCL） wearing for over 5 years in different degrees of keratoconus eyes.MethodsA retrospective case study was performed.The clinical data of 217 eyes with different degree of keratoconus from 126 keratoconus patients who fitted with RGPCL in Beijing Tongren Hospital from 2000—2010 over 5 years were analyzed.The eyes were divided into mild keratoconus group （Ks≤45.0 D）, moderate keratoconus group （45.0 D〈 Ks 〈 52.0 D） and severe keratoconus group （Ks≥52.0 D） according to the severity.Uncorrected visual acuity （UCVA, LogMAR）, spectacle corrected visual acuity （SCVA） and RGP corrected visual acuity （RGPVA） was examined before RGPCL wearing and the end of following-up after RGPCL wearing.The refraction, corneal curvature, corneal astigmatism were measured with auto-refractomer/ keratometer and keratoconus screening analysis system of computer-assisted corneal topography.Comparisons of the changes of corrected visual acuity and corneal parameters were assessed.ResultsThe RGPVA was 0.09±0.17, 0.05±0.07 and 0.07±0.07 in the mild, moderate and severe keratoconus group, respectively, showing a significant difference among the three groups （F=0.522, P=0.594）; The ΔKs was （2.25±5.42）, （0.26±3.44） and （-4.52±3.44）D, and ΔKf was （2.06±4.98）, （1.02±3.41） and （-2.03±5.05）D, and the change value of corneal astigmatism was （0.19±2.87）, （-0.78±2.84） and （-2.44±3.77）D in the mild, moderate and severe keratoconus group（all at P〈0.05）, respectively, with the minimum amount of change in the severe keratoconus group.The variation of differential sector index （ΔDSI） was -0.33±1.64, 0.14±3.01 and -2.11±4.28; the variation of center/surround index （ΔCSI） was -0.41±1.07, 0.03±2.22 and -2.49±4.15; the variation of standard deviation of power （ΔSDP） was -0.43±0.64, -0.02±0.89 and -1.67±1.68; the variation of keratoconus prediction index （ΔKPI） was 0.00±0.07, 0.03±0.09 and -0.05±0.11 in the mild, moderate and severe keratoconus group, respectively, and the reduced amount in above parameters was much more in the severe keratoconus group than that in the mild and moderate keratoconus group （all at P〈0.01）. Mild conjunctivitis and corneal affection occurred in 12 eyes （5.5%） during the follow-up.ConclusionsLong-term wearing RGPCL can improve the visual acuity and slow the tendency of corneal curvature increase in keratoconus eyes, and this procedure is safe and effective for the correction of different degree of keratoconus.