title: A hybrid segmentation approach for geographic atrophy in fundus auto-fluorescence images for diagnosis of age-related macular degeneration.
abstract: Fundus auto-fluorescence (FAF) images with hypo-fluorescence indicate geographic atrophy (GA) of the retinal pigment epithelium (RPE) in age-related macular degeneration (AMD). Manual quantification of GA is time consuming and prone to inter- and intra-observer variability. Automatic quantification is important for determining disease progression and facilitating clinical diagnosis of AMD. In this paper we describe a hybrid segmentation method for GA quantification by identifying hypo-fluorescent GA regions from other interfering retinal vessel structures. First, we employ background illumination correction exploiting a non-linear adaptive smoothing operator. Then, we use the level set framework to perform segmentation of hypo-fluorescent areas. Finally, we present an energy function combining morphological scale-space analysis with a geometric model-based approach to perform segmentation refinement of false positive hypo- fluorescent areas due to interfering retinal structures. The clinically apparent areas of hypo-fluorescence were drawn by an expert grader and compared on a pixel by pixel basis to our segmentation results. The mean sensitivity and specificity of the ROC analysis were 0.89 and 0.98%.
authors.affiliation: Heffner Biomedical Imaging Lab, Department of Biomedical Engineering, Columbia University, CO 80305, USA. nl2168@columbia.edu
authors.forename: Noah
authors.initials: N
authors.lastname: Lee
authors.forename: Andrew F
authors.initials: AF
authors.lastname: Laine
authors.forename: R Theodore
authors.initials: RT
authors.lastname: Smith
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001284:Atrophy; D018450:Disease Progression; D005451:Fluorescein Angiography; D005654:Fundus Oculi; D006801:Humans; D008062:Lipofuscin; D008268:Macular Degeneration / Q000175:diagnosis* / Q000473:pathology; D009887:Ophthalmoscopy / Q000379:methods*; D012372:ROC Curve; D012189:Retrospective Studies; D014792:Visual Acuity
chemical_list: D008062:Lipofuscin