Eye Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.
Health Promotion Research Center, Zahedan University of Medical Sciences, Zahedan, Iran.
Eye (Lond). 2023 Jun;37(8):1665-1672. doi: 10.1038/s41433-022-02218-9. Epub 2022 Aug 29.
To assess the detection ability of corneal biomechanical parameters for early diagnosis of ectasia.
This retrospective descriptive-analytical study included 134 normal eyes (control group) from 134 healthy subjects and 128 eyes with asymmetric contralateral corneal ectasia with normal topography (ACE-NT, study group) from 128 subjects with definite keratoconus in the opposite eye. Placido-disk-based corneal topography with TMS-4, Scheimpflug corneal tomography with Pentacam HR, and corneal biomechanical assessment with Corvis ST and ocular response analyzer (ORA) were performed. A general linear model was used to compare Corvis ST and ORA biomechanical parameters between groups, while central corneal thickness (CCT) and biomechanically corrected intraocular pressure (bIOP) were considered covariates. Receiving operator sensitivity curve (ROC) analysis was used to determine the cut-off point with the highest sensitivity and specificity along with the area under the curve (AUC) for each parameter.
All parameters of Corvis ST and ORA showed a statistically significant difference between the two groups except for the first (P = 0.865) and second (P = 0.226) applanation lengths, and deformation amplitude (P = 0.936). The discriminative analysis of corneal biomechanical showed that the highest accuracy for the classic, new, and combined parameters of Corvis ST was related to HCR (AUC: 0.766), IR & DAR (0.846), and TBI (0.966), respectively. Using ORA, the corneal resistance factor (0.866) had a higher detection ability than corneal hysteresis (0.826).
TBI has the best accuracy and the highest effect size for differential diagnosis of normal from ACE-NT eyes with a cut-off point of 0.24.
评估角膜生物力学参数对早期诊断扩张症的检测能力。
本回顾性描述性分析研究纳入了 134 名正常眼（对照组）和 128 名对侧角膜扩张伴正常地形图的不对称性对侧角膜扩张眼（ACE-NT 组）的 134 名健康受试者和 128 名受试者。使用 TMS-4 进行基于 Placido 盘的角膜地形图检查、Pentacam HR 进行 Scheimpflug 角膜断层扫描、Corvis ST 和 ORA 进行角膜生物力学评估。采用一般线性模型比较两组间 Corvis ST 和 ORA 生物力学参数，同时考虑中央角膜厚度（CCT）和生物力学校正眼压（bIOP）作为协变量。采用接收者操作特征曲线（ROC）分析确定每个参数的最高敏感性和特异性以及曲线下面积（AUC）的最佳截断点。
除了第一（P=0.865）和第二（P=0.226）压平长度和变形幅度（P=0.936）外，Corvis ST 和 ORA 的所有参数在两组间均有统计学差异。角膜生物力学的判别分析显示，Corvis ST 的经典、新和联合参数中，HCR（AUC：0.766）、IR&DAR（0.846）和 TBI（0.966）的准确性最高。使用 ORA，角膜阻力因子（0.866）的检测能力高于角膜滞后（0.826）。
TBI 对正常 ACE-NT 眼的鉴别诊断具有最佳的准确性和最高的效应量，截断点为 0.24。
