Scanning Laser Ophthalmoscopy (SLO) utilizes the eye’s cornea and lens as the imaging objective. Thus, in a perfect eye the Numerical Aperture (NA) defined by the eye’s fully dilated pupil would limit the resolution that can be achieved. However, the eye’s ocular aberrations “blur the image”, thereby limiting the pupil size and NA for aberrationless SLO imaging. By combining SLO with Adaptive Optics (AO), AO-SLO systems can correct for ocular aberrations even over large pupil sizes and allow diffraction limited resolution in both axial and lateral directions. Here, we evaluate the effects of ocular aberrations on the performance of mouse retinal imaging with SLO and AO-SLO systems. To achieve this we first measured the RMS error of the wavefront aberrations in two populations of mice of different ages. Then, we simulated the imaging PSF and resulting lateral resolution that could be achieved with varied input beam diameter (NA) at the mouse pupil, assuming the presence of ocular aberrations (simulation of SLO imaging) and no aberrations (simulation of perfect AO-SLO imaging). The SLO system performance along with different imaging beam sizes was further assessed by computing the PSF Strehl Ratio. Finally, the advantages and limitations of SLO and AO-SLO retinal imaging in mice are discussed based on presented results.
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