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Abstract. In this paper we propose a blind deconvolution approach for reconstruction of Adaptive Optics (AO) high-resolution retinal images. The framework employs Random Forest to learn the mapping of retinal images onto the space of blur kernels expressed in terms of Zernike coefficients. A specially designed feature extraction technique allows inference of blur kernels for retinal images of various quality, taken at different locations of the retina. This model is validated on synthetically generated images as well as real AO highresolution retinal images. The obtained results on the synthetic data showed an average root-mean-square error of 0.0051 for the predicted blur kernels and 0.0464 for the reconstructed images, compared to the ground truth (GT). The assessment of the reconstructed AO retinal images demonstrated that the contrast, sharpness and visual quality of the images have been significantly improved.

Automated analysis of retinal images plays a vital role in the examination, diagnosis, and prognosis of healthy and pathological retinas. Retinal disorders and the associated visual loss can be interpreted via quantitative correlations, based on measurements of photoreceptor loss. Therefore, it is important to develop reliable tools for identification of photoreceptor cells. In this paper, an automated algorithm is proposed, based on the use of the Hessian-Laplacian of Gaussian filter, which allows enhancement and detection of photoreceptor cells. The performance of the proposed technique is evaluated on both synthetic and high-resolution retinal images, in terms of packing density. The results on the synthetic data were compared against ground truth as well as cone counts obtained by the Li and Roorda algorithm. For the synthetic datasets, our method showed an average detection accuracy of 98.8%, compared to 93.9% for the Li and Roorda approach. The packing density estimates calculated on the retinal datasets were validated against manual counts and the results obtained by a proprietary software from Imagine Eyes and the Li and Roorda algorithm. Among the tested methods, the proposed approach showed the closest agreement with manual counting.

An automated image processing system for the detection of photoreceptor cells in adaptive optics retinal images. (Unpublished Doctoral thesis, City,