PURPOSE: Quantitative assessment of nerve fiber layer (NFL) thinning over time in the glaucomatous monkey model using Optical Coherence Tomography (OCT). METHODS: Glaucoma was induced in one eye of seven cynomolgus monkeys using argon laser to the trabecular meshwork; the contralateral eye was maintained as a control. Six of the seven monkeys developed elevated intraocular pressure (IOP) following laser treatment. The monkeys were followed for 3-4 months with weekly examinations, including stereoscopic biomicroscopy, pneumatonometry, NFL photography, stereoscopic disc photography and OCT. RESULTS: Glaucomatous cupping occurred in eyes with elevated IOP, but not in control eyes. NFL thinning could be tracked over time using OCT, and was apparent prior to evidence of NFL loss by conventional means. In eyes with elevated IOP, mean monthly change in NFL thickness varied from -24.4 μm (inferior quadrant) to - 11.7 μm (temporal quadrant), while in control eyes, NFL thinning varied from -4.3 μm (superior quadrant) to +0.6 μm (nasal quadrant). There was a significant difference (p≤0.0001) between the control and glaucomatous eye in every quadrant except temporal. CONCLUSIONS: OCT can track changes in NFL thickness over time. The glaucomatous monkey model demonstrates that changes in NFL thickness shown by OCT are manifest prior to detection by conventional techniques, such as clinical examination and NFL photography.
|Original language||English (US)|
|Journal||Investigative Ophthalmology and Visual Science|
|State||Published - Feb 15 1996|
ASJC Scopus subject areas
- Sensory Systems
- Cellular and Molecular Neuroscience