Department of Ophthalmology, Cerrahpasa School of Medicine, Istanbul University, Istanbul, Turkey.
J Glaucoma. 2013 Dec;22(9):740-5. doi: 10.1097/IJG.0000000000000036.
The aims of this study were to assess the biomechanical properties of corneas with pseudoexfoliative glaucoma (PEXG) and to compare them with those of patients with primary open-angle glaucoma (POAG).
This prospective, comparative case series consisted of 73 eyes of 73 patients, 35 eyes with PEXG (PEXG group) and 38 eyes with POAG (POAG group). Corneal hysteresis (CH), corneal resistance factor (CRF), corneal-compensated intraocular pressure (IOPCC), and Goldmann-correlated intraocular pressure (IOPG) were determined by using ocular response analyzer (ORA). IOP using Goldmann applanation tonometer (GAT) and ultrasonic central corneal thickness (CCT) were also measured for each eye. Exclusion criteria included refractive error/astigmatism of >3.00 D, history of intraocular surgery, corneal disease, angle-closure glaucoma, and secondary glaucoma other than PEXG. In cases where both eyes were eligible, the right eye was preferred for analysis. The main outcome measures were CH, CRF, IOPCC, IOPG, and GAT. The results were statistically analyzed by using t test, general linear model, and the Pearson correlation test.
The mean CH was found to be significantly lower in patients with PEXG (8.8 ± 1.4 mm Hg) than those with primary open-angle glaucoma (9.9 ± 1.2 mm Hg; P=0.0007). The mean CRF was found to be significantly lower in patients with PEXG (9.5 ± 1.8 mm Hg) than those with POAG (11.1 ± 1.3 mm Hg; P<0.0001). IOPCC was not significantly different between the groups (PEXG, 16.7 ± 2.5 mm Hg; POAG, 16.9 ± 2.4 mm Hg; P=0.72). IOPG was significantly lower in PEXG group (14.7 ± 2.7 mm Hg) compared with the POAG group (16.5 ± 2.5 mm Hg; P=0.004). GAT was significantly lower in the PEXG group (14.6 ± 2.7 mm Hg) compared with the POAG group (16.4 ± 2.8 mm Hg; P=0.007). There was no significant difference between the groups regarding mean CCT (PEXG, 546.1 ± 34.9 μ; POAG, 549.1 ± 25 μ; P=0.66) and mean age (PEXG, 70.3 ± 8.2; POAG, 67.6 ± 8.8; P=0.17). The difference between the IOPCC and the GAT was 2.1 and 0.5 mm Hg in both PEXG and POAG groups, respectively.
Patients with PEXG had lower CH and CRF values than those with POAG. These findings require further investigation to assess the role of differing corneal biomechanical properties between the 2 groups and its association with poor prognosis among patients with PEXG.
本研究旨在评估假性剥脱性青光眼（PEXG）患者的角膜生物力学特性，并与原发性开角型青光眼（POAG）患者进行比较。
这是一项前瞻性、对照病例系列研究，共纳入 73 例 73 只眼患者，其中 35 只眼为 PEXG（PEXG 组），38 只眼为 POAG（POAG 组）。使用眼反应分析仪（ORA）测量角膜滞后（CH）、角膜阻力因子（CRF）、角膜补偿眼压（IOPCC）和 Goldmann 相关眼压（IOPG）。每个眼还测量了 Goldmann 压平眼压计（GAT）和超声中央角膜厚度（CCT）的眼压。排除标准包括屈光不正/散光>3.00 D、眼内手术史、角膜疾病、闭角型青光眼和除 PEXG 以外的继发性青光眼。如果双眼都符合条件，则首选右眼进行分析。主要观察指标为 CH、CRF、IOPCC、IOPG 和 GAT。使用 t 检验、一般线性模型和 Pearson 相关检验对结果进行统计学分析。
发现 PEXG 患者的平均 CH（8.8±1.4mmHg）明显低于 POAG 患者（9.9±1.2mmHg；P=0.0007）。发现 PEXG 患者的平均 CRF（9.5±1.8mmHg）明显低于 POAG 患者（11.1±1.3mmHg；P<0.0001）。两组间 IOPCC 无显著差异（PEXG 组，16.7±2.5mmHg；POAG 组，16.9±2.4mmHg；P=0.72）。与 POAG 组相比，PEXG 组的 IOPG 明显较低（14.7±2.7mmHg；P=0.004）。与 POAG 组相比，PEXG 组的 GAT 明显较低（14.6±2.7mmHg；P=0.007）。两组间平均 CCT（PEXG 组，546.1±34.9μm；POAG 组，549.1±25μm；P=0.66）和平均年龄（PEXG 组，70.3±8.2 岁；POAG 组，67.6±8.8 岁；P=0.17）无显著差异。在 PEXG 和 POAG 组中，IOPCC 和 GAT 之间的差值分别为 2.1mmHg 和 0.5mmHg。
与 POAG 患者相比，PEXG 患者的 CH 和 CRF 值较低。这些发现需要进一步研究，以评估两组之间不同角膜生物力学特性的作用及其与 PEXG 患者预后不良的关系。
