Toris Carol B, Koepsell Scott A, Yablonski Michael E, Camras Carl B
Department of Ophthalmology, University of Nebraska Medical Center, Omaha, Nebraska 68198-5540, USA.
J Glaucoma. 2002 Jun;11(3):253-8. doi: 10.1097/00061198-200206000-00015.
To evaluate the mechanism of the intraocular pressure (IOP) elevation in ocular hypertension (OHT), aqueous humor dynamics were compared in patients with OHT versus age-matched ocular normotensive (NT) volunteers.
In this retrospective study, one group included patients diagnosed with OHT (IOPs > 21 mm Hg, n = 55) for at least six months. All eye medications were discontinued for at least three weeks before the study visit. A second group included age-matched NT subjects (n = 55) with no eye diseases. The study visit included measurements of IOP by pneumatonometry, aqueous flow and outflow facility by fluorophotometry, anterior chamber depth and corneal thickness by pachymetry and episcleral venous pressure by venomanometry. Uveoscleral outflow and anterior chamber volume were calculated mathematically.
Significant differences in the OHT versus the NT groups were as follows: increased IOP (21.4 +/- 0.6 versus 14.9 +/- 0.3 mm Hg, respectively; P < 0.0001), reduced uveoscleral outflow (0.66 +/- 0.11 versus 1.09 +/- 0.11 microL/min; P = 0.005) and reduced fluorophotometric outflow facility (0.17 +/- 0.01 versus 0.27 +/- 0.02 microL/min/mm Hg; P < 0.0001). With respect to age, anterior chamber volume decreased in both groups at a rate of 2.4 +/- 0.3 microL/year (r(2) = 0.5, P <.001) and aqueous flow decreased at a rate of 0.013 +/- 0.005 microL/min/year (r(2) = 0.07, P = 0.005).
The increased IOP in ocular hypertensive patients is caused by a reduction in trabecular outflow facility and uveoscleral outflow. Aqueous flow remains normal. When both ocular normotensive and hypertensive groups are combined, aqueous flow and anterior chamber volume decrease slightly with age.
为评估高眼压症（OHT）患者眼压（IOP）升高的机制，比较了高眼压症患者与年龄匹配的眼压正常（NT）志愿者的房水动力学。
在这项回顾性研究中，一组纳入了诊断为高眼压症（眼压>21 mmHg，n = 55）至少6个月的患者。在研究访视前，所有眼部药物至少停用3周。另一组纳入年龄匹配且无眼部疾病的眼压正常受试者（n = 55）。研究访视包括通过眼压计测量眼压、通过荧光光度法测量房水流量和流出易度、通过测厚仪测量前房深度和角膜厚度以及通过静脉压测量法测量巩膜静脉压。通过数学计算得出葡萄膜巩膜流出量和前房容积。
高眼压症组与眼压正常组的显著差异如下：眼压升高（分别为21.4±0.6与14.9±0.3 mmHg；P<0.0001）、葡萄膜巩膜流出量减少（0.66±0.11与1.09±0.11 μL/min；P = 0.005）以及荧光光度法流出易度降低（0.17±0.01与0.27±0.02 μL/min/mm Hg；P<0.0001）。关于年龄，两组的前房容积均以2.4±0.3 μL/年的速率下降（r² = 0.5，P<0.001），房水流量以0.013±0.005 μL/min/年的速率下降（r² = 0.07，P = 0.005）。
高眼压症患者眼压升高是由小梁网流出易度和葡萄膜巩膜流出量减少所致。房水流量保持正常。当眼压正常组和高眼压组合并时，房水流量和前房容积随年龄略有下降。
