A超角膜测厚仪和Pentacam系统测量散瞳前后角膜中央厚度的比较

  目的  比较应用A超角膜测厚仪和Pentacam三维眼前节分析系统测量的散瞳前后角膜中央厚度的差异。  方法  2011年8月至11月北京协和医院成人屈光不正患者65例(130眼), 均先后应用Pentacam三维眼前节分析系统和A超角膜测厚仪进行散瞳前后角膜中央厚度的测量, 散瞳剂采用复方托吡卡胺滴眼液。  结果  A超角膜测厚仪测量的散瞳前后角膜中央厚度值分别为(536.70±39.60)和(548.31±39.22)μm, 散瞳后的测量值明显高于散瞳前(P=0.000);Pentacam三维眼前节分析系统测量的散瞳前后角膜中央厚度值分别为(539.57±39.73)和(545.99±39.47)μm, 散瞳后的测量值亦明显高于散瞳前(P=0.000)。两种方法散瞳前角膜中央厚度的测量值比较, Pentacam三维眼前节分析系统测量值明显高于A超角膜测厚仪(P=0.000);而两种方法散瞳后的测量值比较, 差异无统计学意义(P=0.081)。  结论  散瞳后角膜中央厚度测量值较散瞳前略有增加, 故散瞳前测量值更能准确、真实地反映角膜中央厚度, 有助于为角膜屈光手术方式的选择和手术安全性评价提供参考。

Comparison of Central Corneal Thickness Before and After Mydriasis Measured with A-ultrasound Pachymetry and Pentacam Scheimpflug System

Objective To compare the difference of central corneal thickness （CCT） before and after my- driasis measured with A-ultrasound pachymetry and Pentacam three-dimensional anterior segment analysis system. Methods From August 2011 to November 2011, the CCT of 130 eyes from 65 adult patients with myopia in Pe- king Union Medical College Hospital were measured with A-ultrasound pachymetry and Pentacam Scheimpflug system before and after mydriasis using compound tropicamide eye drops. Results The CCT values obtained with A-ultrasound pachymetry before and after mydriasis were （536. 70 ± 39.60） μm and （548.31± 39.22） μm, respectively. The value after mydriasis was significantly higher than that before mydriasis （P = 0. 000）. The CCT values obtained with Pentacam three-dimensional anterior segment analysis system before and after mydriasis were （539.57± 39.73） μm and （545.99± 39.47） μm, respectively. The value after mydriasis was also significant- ly higher than that before mydriasis （P = 0. 000）. CCT value obtained with Pentacam three-dimensional anterior segment analysis system was significantly higher than A-ultrasound pachymetry before mydriasis （ P = 0. 000 ） ;however, there was no significant difference in CCT between the two methods after mydriasis （P =0. 081 ）. Con- clusions Values of CCT measured after mydriasis are higher than before mydriasis. Therefore, the values of CCT measured before mydriasis may be more accurate, which can help to provide a better option for choosing operative methods and evaluating the safety of refractive surgery.