We have developed a compact retinal imager that integrates adaptive optics (AO) into a line scanning laser ophthalmoscope (LSLO). The bench-top AO-LSLO instrument significantly reduces the size, complexity, and cost of research AOSLOs, for the purpose of moving adaptive optics imaging more rapidly into routine clinical use. The AO-LSLO produces high resolution retinal images with only one moving part and a significantly reduced instrument footprint and number of optical components. The AO-LSLO has a moderate field of view (5.5 deg), which allows montages of the macula or other targets to be obtained more quickly and efficiently. In a preliminary human subjects investigation, photoreceptors could be resolved and counted within ~0.5 mm of the fovea. Photoreceptor counts matched closely to previously reported histology. The capillaries surrounding the foveal avascular zone could be resolved, as well as cells flowing within them. Individual nerve fiber bundles could be resolved, especially near the optic nerve head, as well as other structures such as the lamina cribrosa. In addition to instrument design, fabrication, and testing, software algorithms were developed for automated image registration, cone counting, and montage stitching.
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