University of Houston College of Optometry, Houston, Texas.
Optom Vis Sci. 2020 Sep;97(9):661-668. doi: 10.1097/OPX.0000000000001567.
Scleral lenses (SLs) are increasing in scope, and understanding their ocular health impact is imperative. The unique fit of an SL raises concern that the landing zone causes compression of conjunctival tissue that can lead to resistance of aqueous humor outflow and increased intraocular pressure (IOP).
This study aimed to assess changes in optic nerve head morphology as an indirect assessment of IOP and evaluate other IOP assessment methods during SL wear.
Twenty-six healthy adults wore SL on one randomly selected eye for 6 hours, whereas the fellow eye served as a control. Global minimum rim width (optical coherence tomography) and IOP (Icare, Diaton) were measured at baseline, 2 and 6 hours after SL application, and again after SL removal. Central corneal thickness, anterior chamber depth, and fluid reservoir depth were monitored.
Minimum rim width thinning was observed in the test (-8 μm; 95% confidence interval [CI], -11 to -6 μm) and control (-6 μm; 95% CI, -9 to -3 μm) eyes after 6 hours of SL wear (P < .01), although the magnitude of thinning was not significantly greater in the lens-wearing eyes (P = .09). Mean IOP (Icare) significantly increased +2 mmHg (95% CI, +1 to +3 mmHg) in the test eyes (P = .002), with no change in the control eyes. Mean IOP changes with Diaton were +0.3 mmHg (95% CI, -0.9 to +3.2 mmHg) in the test eyes and +0.4 mmHg (95% CI, -0.8 to +1.7 mmHg) in the control eyes. However, Diaton tonometry showed poor within-subject variation and poor correlation with Icare. No clinically significant changes were observed in central corneal thickness or anterior chamber depth.
This study suggests that SLs have a minimal effect on IOP homeostasis in the normal eye during SL wear and an insignificant impact on the optic nerve head morphology in healthy adult eyes.
巩膜镜片（SL）的应用范围越来越广，了解其对眼部健康的影响至关重要。SL 的独特贴合方式引起了人们的关注，即镜片的着陆区会导致结膜组织受压，从而导致房水流出阻力增加，眼内压（IOP）升高。
本研究旨在评估视神经头形态的变化，作为 IOP 的间接评估，并评估 SL 佩戴期间其他 IOP 评估方法。
26 名健康成年人随机选择一只眼佩戴 SL 6 小时，对侧眼作为对照。在基线、SL 应用后 2 小时和 6 小时以及 SL 去除后再次测量全局最小边缘宽度（光学相干断层扫描）和 IOP（Icare、Diaton）。监测中央角膜厚度、前房深度和液体储层深度。
佩戴 SL 6 小时后，试验眼（-8μm；95%置信区间[CI]，-11 至-6μm）和对照眼（-6μm；95%CI，-9 至-3μm）的最小边缘宽度均出现变薄（P<0.01），但镜片眼的变薄程度无显著差异（P=0.09）。试验眼的平均 IOP（Icare）显著升高+2mmHg（95%CI，+1 至+3mmHg）（P=0.002），对照眼无变化。Diaton 测量的平均 IOP 变化为试验眼+0.3mmHg（95%CI，-0.9 至+3.2mmHg）和对照眼+0.4mmHg（95%CI，-0.8 至+1.7mmHg）。然而，Diaton 眼压计的个体内变异性较差，与 Icare 的相关性也较差。中央角膜厚度或前房深度无临床意义的变化。
本研究表明，在正常眼中，SL 在佩戴期间对 IOP 稳态的影响很小，对健康成年人眼睛的视神经头形态也没有明显影响。
