Sedaghat Mohamad Reza, Ostadi-Moghadam Hadi, Jabbarvand Mahmoud, Askarizadeh Farshad, Momeni-Moghaddam Hamed, Narooie-Noori Foroozan
Cornea Research Center, Khatam-Al-Anbia Hospital, Mashhad University of Medical Sciences, Mashhad, Iran.
Department of Optometry, School of Paramedical Sciences, Mashhad University of Medical Sciences, Mashhad, Iran.
J Curr Ophthalmol. 2017 Aug 18;30(1):42-47. doi: 10.1016/j.joco.2017.08.002. eCollection 2018 Mar.
To evaluate and compare corneal hysteresis (CH) and corneal resistance factor (CRF) in pellucid marginal degeneration (PMD), keratoconus (KCN), and normal eyes using the Ocular Response Analyzer (ORA).
In this retrospective study, corneal biomechanical parameters were measured in patients with PMD ( = 102) and KCN ( = 202) and normal subjects ( = 208) using the ORA. Data, including full patient history as well as the results of refraction, slit-lamp biomicroscopy, Pentacam HR (Oculus), and ORA (Reichert; Buffalo, New York, USA), were collected from medical records. Also, the data of only one eye per individual were selected for the analysis. The inclusion criteria for PMD and KCN groups were a reliable diagnosis of these ectatic disorders based on the clinical and corneal tomographic findings. CH, CRF, CH-CRF, intraocular pressure (IOP) measurements were assessed for each subject. Data were analyzed with SPSS and MedCalc using the ANOVA, Pearson Correlation, and receiver operating characteristic (ROC) curve analysis.
The mean CH was 8.91 mmHg ± 1.05 [standard deviation (SD)], 8.43 ± 0.78, and 10.89 ± 1.08 in the PMD, KCN, and normal group, respectively. Also, the mean CRF was 8.21 ± 1.35, 7.19 ± 1.11, and 10.69 ± 1.41 in the PMD, KCN, and normal group, respectively. ANOVA showed differences in the mean CH, CRF, and CH-CRF between three groups ( < 0.001). Also, ROC curve analysis showed the cut-off points ≤9.5, ≤9.5, and >1.3 mmHg for CH, CRF, and CH-CRF in the PMD group, respectively. For biomechanical parameters in PMD eyes, CRF had the highest sensitivity (75.49%) while the greatest area under the ROC curve (AUC) was seen for CH (0.903). Moreover, central corneal thickness (CCT) showed no correlation with CH ( = 0.30, = -0.104) or CRF ( = 0.75, = 0.033) in the PMD group.
This study presented the values of corneal biomechanics for PMD using the ORA. The results of the ORA were markedly different between PMD, KCN, and normal eyes.
使用眼反应分析仪（ORA）评估并比较透明边缘变性（PMD）、圆锥角膜（KCN）和正常眼的角膜滞后（CH）和角膜阻力因子（CRF）。
在这项回顾性研究中，使用ORA测量了PMD患者（n = 102）、KCN患者（n = 202）和正常受试者（n = 208）的角膜生物力学参数。从病历中收集了包括完整患者病史以及验光、裂隙灯生物显微镜检查、Pentacam HR（Oculus）和ORA（Reichert；美国纽约州布法罗）结果的数据。此外，分析时选取每个个体仅一只眼的数据。PMD和KCN组的纳入标准是基于临床和角膜断层扫描结果对这些扩张性疾病的可靠诊断。评估了每个受试者的CH、CRF、CH-CRF、眼压（IOP）测量值。使用SPSS和MedCalc通过方差分析、Pearson相关性分析和受试者工作特征（ROC）曲线分析对数据进行分析。
PMD组、KCN组和正常组的平均CH分别为8.91 mmHg±1.05 [标准差（SD）]、8.43±0.78和10.89±1.08。同样，PMD组、KCN组和正常组的平均CRF分别为8.21±1.35、7.19±1.11和10.69±1.41。方差分析显示三组之间的平均CH、CRF和CH-CRF存在差异（P < 0.001）。此外，ROC曲线分析显示PMD组中CH、CRF和CH-CRF的截断点分别≤9.5、≤9.5和>1.3 mmHg。对于PMD眼的生物力学参数，CRF具有最高的敏感性（75.49%），而CH的ROC曲线下面积（AUC）最大（0.903）。此外，PMD组中中央角膜厚度（CCT）与CH（r = 0.30，P = -0.104）或CRF（r = 0.75，P = 0.033）均无相关性。
本研究使用ORA给出了PMD的角膜生物力学值。ORA在PMD、KCN和正常眼之间的结果明显不同。
