title: Variable background active contour model for computer-aided delineation of nodules in thyroid ultrasound images.
abstract: This paper presents a computer-aided approach for nodule delineation in thyroid ultrasound (US) images. The developed algorithm is based on a novel active contour model, named variable background active contour (VBAC), and incorporates the advantages of the level set region-based active contour without edges (ACWE) model, offering noise robustness and the ability to delineate multiple nodules. Unlike the classic active contour models that are sensitive in the presence of intensity inhomogeneities, the proposed VBAC model considers information of variable background regions. VBAC has been evaluated on synthetic images, as well as on real thyroid US images. From the quantification of the results, two major impacts have been derived: 1) higher average accuracy in the delineation of hypoechoic thyroid nodules, which exceeds 91%; and 2) faster convergence when compared with the ACWE model.
authors.affiliation: Realtime Systems and Image Analysis Group, Department of Informatics and Telecommunications, University of Athens, Athens 15784, Greece. rtsimage@di.uoa.gr
authors.forename: Dimitris E
authors.initials: DE
authors.lastname: Maroulis
authors.forename: Michalis A
authors.initials: MA
authors.lastname: Savelonas
authors.forename: Dimitris K
authors.initials: DK
authors.lastname: Iakovidis
authors.forename: Stavros A
authors.initials: SA
authors.lastname: Karkanis
authors.forename: Nikos
authors.initials: N
authors.lastname: Dimitropoulos
mesh_terms: D001185:Artificial Intelligence; D003198:Computer Simulation; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008954:Models, Biological; D010363:Pattern Recognition, Automated / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016606:Thyroid Nodule / Q000000981:diagnostic imaging*; D014463:Ultrasonography / Q000379:methods*