title: Semi-automated identification of cones in the human retina using circle Hough transform.
abstract: A large number of human retinal diseases are characterized by a progressive loss of cones, the photoreceptors critical for visual acuity and color perception. Adaptive Optics (AO) imaging presents a potential method to study these cells in vivo. However, AO imaging in ophthalmology is a relatively new phenomenon and quantitative analysis of these images remains difficult and tedious using manual methods. This paper illustrates a novel semi-automated quantitative technique enabling registration of AO images to macular landmarks, cone counting and its radius quantification at specified distances from the foveal center. The new cone counting approach employs the circle Hough transform (cHT) and is compared to automated counting methods, as well as arbitrated manual cone identification. We explore the impact of varying the circle detection parameter on the validity of cHT cone counting and discuss the potential role of using this algorithm in detecting both cones and rods separately.
authors.affiliation: Centre for Ophthalmology and Visual Science, The University of Western Australia, 35 Stirling Highway Crawley WA 6009 Perth, Australia ; Lions Eye Institute, 2 Verdun Street, Nedlands WA 6009, Perth, Australia.
authors.forename: Danuta M
authors.initials: DM
authors.lastname: Bukowska
authors.affiliation: Centre for Ophthalmology and Visual Science, The University of Western Australia, 35 Stirling Highway Crawley WA 6009 Perth, Australia ; Lions Eye Institute, 2 Verdun Street, Nedlands WA 6009, Perth, Australia.
authors.forename: Avenell L
authors.initials: AL
authors.lastname: Chew
authors.affiliation: Lions Eye Institute, 2 Verdun Street, Nedlands WA 6009, Perth, Australia.
authors.forename: Emily
authors.initials: E
authors.lastname: Huynh
authors.affiliation: Centre for Ophthalmology and Visual Science, The University of Western Australia, 35 Stirling Highway Crawley WA 6009 Perth, Australia.
authors.forename: Irwin
authors.initials: I
authors.lastname: Kashani
authors.affiliation: Centre for Ophthalmology and Visual Science, The University of Western Australia, 35 Stirling Highway Crawley WA 6009 Perth, Australia ; Lions Eye Institute, 2 Verdun Street, Nedlands WA 6009, Perth, Australia.
authors.forename: Sue Ling
authors.initials: SL
authors.lastname: Wan
authors.affiliation: Centre for Ophthalmology and Visual Science, The University of Western Australia, 35 Stirling Highway Crawley WA 6009 Perth, Australia.
authors.forename: Pak Ming
authors.initials: PM
authors.lastname: Wan
authors.affiliation: Centre for Ophthalmology and Visual Science, The University of Western Australia, 35 Stirling Highway Crawley WA 6009 Perth, Australia ; Lions Eye Institute, 2 Verdun Street, Nedlands WA 6009, Perth, Australia ; Department of Ophthalmology, Royal Perth Hospital, 197 Wellington St, WA 6000, Perth, Australia.
authors.forename: Fred K
authors.initials: FK
authors.lastname: Chen
keywords: (100.0100) Image processing; (110.1080) Active or adaptive optics; (170.3880) Medical and biological imaging; (170.4470) Ophthalmology