Abstract
Purpose: To provide an overview of current approaches for assessing neurodegenerative disorders such as Multiple Sclerosis, Traumatic Brain Injury (TBI), and Parkinson Disease by using structural features of the retina as biological markers for severity and progression of disease. Methods: Spectral Domain Optical Coherence Tomography (SD-OCT) was used to acquire volume scans of the macula and optic nerve in humans with multiple sclerosis and TBI and in mouse models of TBI (blast injury) and Parkinson Disease. Segmentation of the retinal layers provided a means for assessing the thickness of retinal layers containing the retinal ganglion cell complex and the axons within the retinal nerve fiber layer (RNFL) to correlate this with retinal function. Retinal outcome measures are correlated with measures of structure and function of the brain. Results: For each neurodegenerative disorder, there is a statistically significant correlation between inner retinal structure and central nervous system outcome measures. With current SD-OCT eye tracking and reference scan capabilities, the repeat measurement variability is less than 1 micron, allowing the ability to detect very small changes over time to monitor progression. Conclusions: There is evidence that the thickness of the retinal ganglion cell layer and nerve fiber layer may provide surrogate measures for severity of disorders associated with central nervous system degeneration and may also provide a means for monitoring progression. Current studies are under way to correlate retinal structure with quantitative MRI findings in patients with MS every six months to determine the clinical utility of using this approach for making treatment decisions over time.
Meeting abstract presented at OSA Fall Vision 2012