眼前节全景仪与超声波测量角膜厚度的比较

Comparison of anterior segment panoramic instrument and ultrasonic in measurement of central corneal thickness

目的探讨并比较眼前节全景仪与A型超声测厚仪在角膜厚度测量方面的相关性。方法对进行准分子激光手术术前900例(1800眼)近视散光患者,均先后应用德国产鹰视Oculyzer眼前节全景仪常规检查角膜。在显示角膜曲率等信息同时,显示角膜中央厚度,在局部麻醉下用角膜A型超声测厚仪进行角膜中央厚度测量,将两种测量方法所测得的角膜中央厚度进行比较。结果 1800眼患者两种方法测量角膜中央厚度误差在±3.0μm之内吻合900眼(50.0%),±(3.1～6.0)μm吻合500眼(27.8%),±10.0μm范围内吻合1680眼(93.3%),两种测量方法差异无统计学意义。且两种测量方法±10.0μm内吻合率在500～600μm范围内与自然分布几率吻合,不因角膜厚度改变而改变。两种测量方法的误差分布不因曲率的高低变化而不同。结论眼前节全景仪与A超测量角膜中央厚度具有很高吻合性,A超做为金标准的测量方法简单、实用,被普遍应用,但为接触式检查,存在人为误差等缺憾。而眼前节全景仪因非接触性、厚度测量更全面、更方便等特点而显示出更明显的优势。

Objective To investigate and compare the correlation of anterior segment panoramic instrument and A-type ultrasonic in measurement of central corneal thickness.Methods Before excimer laser surgery,900 cases（1 800 eyes） with myopic astigmatism were successively applied common corneal measurement by Germany Oculyzer eagle eye segment panoramic analyzer.At the same time of showing corneal curvature,central corneal thickness was displayed too.Under local anesthesia,A-type ultrasonic thickness instrument was used to detect central corneal thickness.These two kinds of data were compared.Results Of 1800 eyes,fitness of central corneal thickness by the two measurements within ±3.0 μm was 900 eyes（50.0%）,±3.1 μm to ±6.0 μm was 500 eyes（27.8%）,and within ±10.0 μm was 1 680 eyes（93.4%）.The difference was not statistically significant,and error distribution had no difference due to the cornea was too thin or too thick.The error distribution of two measurements did not change with the level of different curvature.Conclusion There is high consistency of anterior segment panoramic instrument with A-type ultrasonic thickness instrument.A-type ultrasony is simple,reliable and commonly used as golden standard,but for its contact examination,there is personal error.While anterior segment panoramic instrument has prominent advantage for its non-contact,more comprehensive and convenient characters.