Relationship between intraocular pressure and retinal nerve fibre thickness loss in a monkey model of chronic ocular hypertension

Eye (Lond). 2019 Dec;33(12):1833-1841. doi: 10.1038/s41433-019-0484-1. Epub 2019 Jun 21.

Abstract

Chronic ocular hypertension (COHT) monkey models were established by destroying the trabecular meshwork, for investigating the relationship between intraocular pressure (IOP) and retinal nerve fibre layer (RNFL) thickness loss. IOP and RNFL thickness were measured before laser injury and weekly thereafter for 27 weeks using Tono Vet and Stratus optical coherence tomography (OCT). The quantitative relationship was as follows: (1) at 32-47 mmHg, the average damage rate was -3.08 ± 0.28 μm/week; (2) at 25-30 mmHg, it was -1.45 ± 0.19 μm/week. The inferior RNFL and superior RNFL turned out to be the most IOP-sensitive quadrants with the rate of RNFL change almost in parallel with IOP levels. The superior sector seemed to be resistant to high IOP conditions until a RNFL loss of ~20 μm was detected in the inferior sector. The rate of RNFL thickness loss was slowed with obvious turning points at RNFL thicknesses of ~75 μm, 65 μm, and 50 μm. The experimental results have achieved research significance. The COHT Monkey was an ideal animal model that can be used for evaluating the relationship between IOP and RNFL damage. Higher IOP was associated with faster RNFL thickness loss. The level of IOP was a vital factor for RNFL damage rate, and baseline/residual RNFL thickness was also important for subsequent RNFL damage. OCT was suitable for measuring RNFL thickness change in COHT monkey models.

目的: 观察恒河猴慢性高眼压模型眼压与视神经纤维损伤的关系。方法: 实验研究。方法: 实验研究。采用眼科多波长激光仪光凝恒河猴的小梁网以破坏小梁网功能使眼压升高, 建立恒河猴慢性高眼压模型。术前和术后每周行眼压和视神经纤维厚度检测。结果: 平均视神经纤维厚度损伤速率与高眼压关系: (1)32–47 mmHg, 损伤速率−3.08 ± 0.28 μm/周;(2)25–30 mmHg, 损伤速率为−1.45 ± 0.19 μm/周。上下方视神经纤维是最容易被高眼压影响的区域, 其损伤速率与高眼压程度呈正比关系, 上方视神经纤维厚度在下方视神经纤维厚度损失20 μm后开始变薄。 随着视神经纤维厚度变薄 其损伤速率会逐渐减慢,节点分别为75 μm, 65 μm和50 μm。结论: 视神经纤维损伤速率与高眼压程度明显相关。眼压越高, 损伤越快。高眼压是视神经纤维厚度损伤最关键因素, 除此之外, 视神经纤维基线厚度和损伤后残余厚度均影响其损伤速率。恒河猴高眼压模型被证明是研究眼压与视神经纤维损伤的理想模型, OCT适合监测该模型的视神经纤维厚度改变变。

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Chronic Disease
  • Disease Models, Animal
  • Glaucoma / pathology
  • Glaucoma / physiopathology*
  • Haplorhini
  • Intraocular Pressure / physiology*
  • Nerve Fibers / pathology*
  • Retinal Ganglion Cells / pathology*
  • Tomography, Optical Coherence / methods*