不同仪器测量角膜直径和角膜曲率的一致性评价

目的比较验光曲率仪、OrbscanⅡz眼前节分析系统和光学相干生物测量仪IOLMaster测量角膜直径和角膜曲率的差异,并评价三种测量结果的一致性。方法对70例(140眼)屈光不正患者,采用三种仪器分别测量双眼角膜水平直径和角膜前表面曲率,对这些参数进行统计学分析,应用Bland-Altman分析对三种测量结果进行一致性评价。结果验光曲率仪和OrbscanⅡz测得的角膜直径分别为(11.51±0.32)mm和(11.52±0.33)mm,差异无统计学意义(P>0.05),一致性较好;IOLMaster测得值为(12.10±0.34)mm,与另外两种仪器所测结果比较差异均有统计学意义(均为P<0.05),一致性较差。三种仪器测得的平均角膜曲率分别为(43.46±1.32)D、(43.36±1.32)D和(43.65±1.35)D,差异均无统计学意义(均为P>0.05),一致性较好。结论三种仪器在临床应用中,验光曲率仪和OrbscanⅡz测得的角膜直径值可相互替代使用,而IOLMaster测得的角膜直径偏大,不宜作为大小角膜的诊断依据。三者测得的角膜曲率值可相互替代使用,但各有优缺点,临床应互相参照、比较,确保眼球生物学参数的可靠性。

Agreement between different instruments for assessing corneal diameter and curvature

Objective To compare the difference of corneal diameter and curvature measured by Ref-keratometer,OrbscanⅡz and IOL Master,and evaluate the agreement of three instruments.Methods Seventy cases(140 eyes) with ametropia used three instruments to measure corneal level diameter and curvature on both eyes,and then analyzed statistically,the Bland-Altman method was used to evaluate the agreement of three instruments.Results The corneal diameter was(11.51±0.32)mm by Ref-keratometer and(11.52±0.33)mm by OrbscanⅡz,there was no statistical difference(P>0.05),and that was(12.10±0.34)mm by IOL Master,there was statistical difference compared with other two instruments(both P<0.05).The corneal curvature was(43.46±1.32)D by Ref-keratometer,(43.36±1.32)D by OrbscanⅡz and(43.65±1.35)D by IOL Master,there was no statistical difference(all P>0.05),and the agreement of three instruments was well.Conclusions Ref-keratometer and OrbscanⅡz can be interchanged for corneal diameter,but the corneal diameter measured by IOL Master is longer,and can not as a diagnosis for macrocornea and microcornea.Three instruments can be interchanged for corneal curvature with advantages and disadvantages,and they should be cross-referenced and compared with each other to ensure the reliability of biological parameters.