Abstract
PURPOSE. Elastic light backscattering spectroscopy (ELBS) has exquisite sensitivity to the ultrastructural properties of tissue and thus has been applied to detect various diseases associated with ultrastructural alterations in their early stages. This study aims to test whether ELBS can detect early damage in retinal ganglion cells (RGCs). METHODS. We used a mouse model of partial optic nerve crush (pONC) to induce rapid RGC death. We confirmed RGC loss by axon counting and characterized the changes in retinal morphology by optical coherence tomography (OCT) and in retinal function by full-field electroretinogram (ERG), respectively. To quantify the ultrastructural properties, elastic backscattering spectroscopic analysis was implemented in the wavelength-dependent images recorded by reflectance confocal microscopy. RESULTS. At 3 days post-pONC injury, no significant change was found in the thickness of the RGC layer or in the mean amplitude of the oscillatory potentials measured by OCT and ERG, respectively; however, we did observe a significantly decreased number of axons compared with the controls. At 3 days post-pONC, we used ELBS to calculate the ultrastructural marker (D), the shape factor quantifying the shape of the local mass density correlation functions. It was significantly reduced in the crushed eyes compared with the controls, indicating the ultrastructural fragmentation in the crushed eyes. CONCLUSIONS. Elastic light backscattering spectroscopy detected ultrastructural neuronal damage in RGCs following the pONC injury when OCT and ERG tests appeared normal. Our study suggests a potential clinical method for detecting early neuronal damage prior to anatomical alterations in the nerve fiber and ganglion cell layers.
Original language | English (US) |
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Pages (from-to) | 5665-5671 |
Number of pages | 7 |
Journal | Investigative Ophthalmology and Visual Science |
Volume | 57 |
Issue number | 13 |
DOIs | |
State | Published - Oct 2016 |
Funding
The authors thank the Northwestern University Atomic and Nanoscale Characterization Experimental Center (NUANCE) for preparation of optic nerve sections. Supported by National Institutes of Health Grants R01EY026286 (XL); DP3DK108248 (HFZ); and R01CA183101 (VB); the National Science Foundation CBET-1055379 (HFZ); a National Natural Science Foundation of China Grant No. 31471054 (PL); and a Program of Introducing Talents of Discipline to Universities Grant No. B08020 (PL).
Keywords
- Axonal degeneration
- Electroretinography
- Ganglion cells
- Optical coherence tomography
- Spectroscopy
ASJC Scopus subject areas
- Sensory Systems
- Cellular and Molecular Neuroscience
- Ophthalmology