Department of Ophthalmology, Kangwon National University School of Medicine, Chuncheon, South Korea.
Department of Ophthalmology, Nowon Eulji Medical Center, Eulji University College of Medicine, Seoul, South Korea.
Invest Ophthalmol Vis Sci. 2022 Feb 1;63(2):23. doi: 10.1167/iovs.63.2.23.
The purpose of this study was to investigate whether the lamina cribrosa (LC) curve changes in response to intraocular pressure (IOP) reduction following administration of topical ocular hypotensive eye drops in eyes with normal tension glaucoma (NTG).
Ninety-three eyes of 93 patients with treatment naïve NTG at initial examination and with ≥20% reduction from baseline IOP following administration of topical ocular hypotensive eye drops were included. Serial horizontal B-scan images of the optic nerve head (ONH) were obtained from each eye using enhanced depth imaging spectral domain optical coherence tomography (OCT) before and 1 year after IOP-lowering treatment. The LC curvature in each eye was assessed by measuring the LC curvature index (LCCI) in horizontal OCT B-scan images obtained at three (superior, central, and inferior) locations spaced equidistantly across the vertical optic disc diameter before and after IOP-lowering treatment. We evaluated the OCT detectible change in the LC curvature based on the interval change of LCCI to exceed the intersession standard deviation of 1.96 times and factors associated with the magnitude of the LCCI change in the eyes showing significant LC change.
IOP decreased from 15.7 ± 2.5 mm Hg at baseline to 11.2 ± 1.7 mm Hg after topical glaucoma medication. Among the 93 subjects, 62 (66.7%) eyes showed the significant reduction of the LCCI (interssetional change over 1.5) after the treatment; greater interssessional change of the LCCI after IOP reduction was associated with younger age (P = 0.020) and larger baseline LCCI (P < 0.001).
The OCT detectible changes in LC curvature occurred in response to a modest decrease in the IOP in the naïve NTG eyes. The therapeutic benefit of these changes need to be assessed in longitudinal studies.
本研究旨在探讨正常眼压性青光眼（NTG）患者在使用局部降眼压眼药水治疗后，眼压（IOP）降低时，是否会引起视盘筛板（LC）曲线发生变化。
本研究纳入了 93 名 NTG 患者的 93 只眼，这些患者在初次检查时眼压正常，在使用局部降眼压眼药水治疗后，IOP 较基线水平降低了≥20%。所有患者在治疗前和治疗后 1 年均使用增强深度成像谱域光学相干断层扫描（OCT）对每只眼的视神经头（ONH）进行了水平位 B 扫描。在治疗前和治疗后，在水平 OCT B 扫描图像上测量 3 个（上方、中央和下方）等距分布在垂直视盘直径上的 LC 曲率指数（LCCI），以评估 LC 曲率。我们评估了 OCT 检测到的 LC 曲率变化，基于 LCCI 的间隔变化超过 1.96 倍的组内标准差，并评估了与治疗后 LC 变化显著的眼的 LCCI 变化幅度相关的因素。
IOP 从基线时的 15.7 ± 2.5mmHg 降至局部降眼压药物治疗后的 11.2 ± 1.7mmHg。在 93 名受试者中，62 只眼（66.7%）在治疗后 LCCI 显著降低（间隔变化超过 1.5）；IOP 降低后 LCCI 的间隔变化越大，年龄越小（P = 0.020），基线 LCCI 越大（P < 0.001）。
在未经治疗的 NTG 眼中，LC 曲率的 OCT 可检测到的变化发生在 IOP 适度降低时。这些变化的治疗效果需要在纵向研究中进行评估。
