Automated cone photoreceptor cell identication in confocal adaptive optics scanning laser ophthalmoscope images based on object detection

Cone photoreceptor cell identication is important for the early diagnosis of retinopathy.In this study,an object detection algorithm is used for cone cell identication in confocal adaptive optics scanning laser ophthalmoscope(AOSLO)images.An effectiveness evaluation of identication using the proposed method reveals precision,recall,and F_(1)-score of 95.8%,96.5%,and 96.1%,respectively,considering manual identication as the ground truth.Various object detection and identication results from images with different cone photoreceptor cell distributions further demonstrate the performance of the proposed method.Overall,the proposed method can accurately identify cone photoreceptor cells on confocal adaptive optics scanning laser ophthalmoscope images,being comparable to manual identication.

Automated superpixels-based identification and mosaicking of cone photoreceptor cells for adaptive optics scanning laser ophthalmoscope

An automated superpixels identification/mosaicking method is presented for the analysis of cone photoreceptor cells with the use of adaptive optics scanning laser ophthalmoscope(AO-SLO) images. This is an image oversegmentation method used for the identification and mosaicking of cone photoreceptor cells in AO-SLO images.It includes image denoising, estimation of the cone photoreceptor cell number, superpixels segmentation, merging of superpixels, and final identification and mosaicking processing steps. The effectiveness of the presented method was confirmed based on its comparison with a manual method in terms of precision, recall, and F1-score of 77.3%, 95.2%, and 85.3%, respectively.

Bimorph deformable mirror based adaptive optics scanning laser ophthalmoscope for retina imaging in vivo

A bimorph deformable mirror （DM） with a large stroke of more than 30 μm using 35 actuators is presented and characterized for an adaptive optics （AO） confocal scanning laser ophthalmoscope application. Facilitated with a Shack-Hartmann wavefront sensor, the bimorph DM-based AO operates closed-loop AO corrections for hu- man eyes and reduces wavefront aberrations in most eyes to below 0.1 μm rms. Results from living eyes, including one exhibiting ~5D of myopia and ~2D of astigmatism along with notable high-order aberrations, reveal a prac- tical efficient aberration correction and demonstrate a great benefit for retina imaging, including improving resolution, increasing brightness, and enhancing the contrast of images.

AB105.Database of retinal images in visually impaired individuals:drusen and age-related macular degeneration(AMD)

Background:With a large portion of older adults living longer,the number of individuals diagnosed with low vision is increasing.The use of optical coherence tomography/scanning laser ophthalmoscope(OCT/SLO)to diagnose retinal disease has become common place in the last 10 years,yet currently there are no OCT/SLO databases for pathological vision.Our aim is to develop a clinical database of individuals who have drusen(i.e.,lipid deposits found under the retina),or have been diagnosed with age-related macular degeneration(AMD),with information as to how the structure of the diseased retina changes over time,as well as measures of visual and cognitive functional performance.Methods:Fundus photographs and retinal scans will be taken using the same model of optos OCT/SLO located in three test sites(MAB-Mackay Rehabilitation Centre,School of Optometry Clinic at the University of Montreal,and the Lighthouse Institute,New York,USA).For each individual entry in the database,demographic and diagnosis information will be available.All OCT/SLO images will be graded according to the Age-related Eye Disease Study standard,in addition to number and size of drusen,severity of geographic atrophy,severity of pigment mottling and presence of choroidal neovascularization.Retinal topography and Raster scans from the OCT/SLO will provide a cross-sectional look at affected retinas.Fixation stability will be recorded using the SLO function,and present four different tasks that are designed to reproduce typical tasks of daily vision,with each task lasting for 10 seconds.The tasks are cross fixation,face recognition,visual search,and reading.These tasks in addition to the retinal scans will be used to determine the eccentricity of a preferred retinal locus from the anatomical fovea,and can be used as an outcome measure for clinical interventions in visually impaired patients.Results:The database will be available to professors training eye-care practitioners and rehabilitation specialists as a teaching tool.Students will be able to familiarize themselves with the retina and a variety of AMD-related pathologies before they start working with patients.The database will also be accessible by researchers interested in studying AMD from basic science to epidemiology,to investigate how drusen and AMD impact visual and cognitive functional performance.Conclusions:The common infrastructure is easily accessible to all VHRN members on request.The database will also be accessible online in 2018(see http://cvl.concordia.ca for more information).