Avitabile T, Marano F, Castiglione F, Reibaldi A
Institute of Ophthalmology, University of Catania, Catania, Italy.
Ophthalmologica. 1998;212 Suppl 1:10-2. doi: 10.1159/000055412.
The diagnosis of keratoconus is based on slip-lamp and keratometric findings, and its classification includes 4 different stages. In this study, we compare the ultrasound biomicroscopy (UBM) findings and the keratoconus index (KI) determined using UBM with the severity of the disease. By means of UBM (Humphrey Instruments system model 840) using a 50-MHz probe, we studied 49 eyes affected with different forms of keratoconus. Using a method previously described, we calculated the KI and compared these data with the findings obtained using videokeratography. The mean thickness at the corneal apex in keratoconic eyes was 0.369 mm, while the mean peripheral corneal thickness was 0.568 mm. The mean KI was 1.449 in keratoconic eyes. The KI increased according to the severity of the disease. The mean central keratometry power was 56.95, while the mean amount of steepening of the inferior cornea compared with that of the superior cornea was 8.16. UBM can be considered a useful tool in the study of keratoconus. Using high-frequency ultrasound, it is also possible to obtain reliable measurements of corneal thickness related to the severity of the disease determined by videokeratography.
圆锥角膜的诊断基于裂隙灯和角膜曲率计检查结果，其分级包括4个不同阶段。在本研究中，我们将超声生物显微镜（UBM）检查结果以及使用UBM测定的圆锥角膜指数（KI）与疾病严重程度进行比较。通过使用50-MHz探头的UBM（Humphrey Instruments系统型号840），我们研究了49只患有不同形式圆锥角膜的眼睛。使用先前描述的方法，我们计算了KI，并将这些数据与使用角膜地形图获得的结果进行比较。圆锥角膜眼的角膜顶点平均厚度为0.369 mm，而周边角膜平均厚度为0.568 mm。圆锥角膜眼的平均KI为1.449。KI随着疾病严重程度增加。中央角膜曲率平均度数为56.95，而下角膜相较于上角膜的平均陡峭度为8.16。UBM可被视为研究圆锥角膜的有用工具。使用高频超声，还能够获得与角膜地形图确定的疾病严重程度相关的可靠角膜厚度测量值。
