title: Identification and localization of fovea on colour fundus images using blur scales.
abstract: Identification of retinal landmarks is an important step in the extraction of anomalies in retinal fundus images. In the current study, we propose a technique to identify and localize the position of macula and hence the fovea avascular zone, in colour fundus images. The proposed method, based on varying blur scales in images, is independent of the location of other anatomical landmarks present in the fundus images. Experimental results have been provided using the open database MESSIDOR by validating our segmented regions using the dice coefficient, with ground truth segmentation provided by a human expert. Apart from testing the images on the entire MESSIDOR database, the proposed technique was also validated using 50 normal and 50 diabetic retinopathy chosen digital fundus images from the same database. A maximum overlap accuracy of 89.6%-93.8% and locational accuracy of 94.7%-98.9% was obtained for identification and localization of the fovea.
authors.affiliation: Department of Electronic and Computer Engineering (ECE), Ngee Ann Polytechnic, Singapore g.karthikeya@gmail.com.
authors.forename: Karthikeyan
authors.initials: K
authors.lastname: Ganesan
authors.affiliation: Department of Electronic and Computer Engineering (ECE), Ngee Ann Polytechnic, Singapore Department of Biomedical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Rajendra U
authors.initials: RU
authors.lastname: Acharya
authors.affiliation: Department of Electronic and Computer Engineering (ECE), Ngee Ann Polytechnic, Singapore.
authors.forename: Chua Kuang
authors.initials: CK
authors.lastname: Chua
authors.affiliation: National Healthcare Group Eye Institute, Tan Tock Seng Hospital, Singapore.
authors.forename: Augustinus
authors.initials: A
authors.lastname: Laude
mesh_terms: D016208:Databases, Factual; D003930:Diabetic Retinopathy / Q000473:pathology; D005584:Fovea Centralis / Q000033:anatomy & histology / Q000473:pathology*; D005654:Fundus Oculi; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D010781:Photography
keywords: Fovea avascular zone detection; blur scales; diabetic retinopathy; fovea localization; fundus images