title: Rolling ball sifting algorithm for the augmented visual inspection of carotid bruit auscultation.
abstract: Carotid bruits are systolic sounds associated with turbulent blood flow through atherosclerotic stenosis in the neck. They are audible intermittent high-frequency (above 200 Hz) sounds mixed with background noise and transmitted low-frequency (below 100 Hz) heart sounds that wax and wane periodically. It is a nontrivial task to extract both bruits and heart sounds with high fidelity for further computer-aided auscultation and diagnosis. In this paper we propose a rolling ball sifting algorithm that is capable to filter signals with a sharper frequency selectivity mechanism in the time domain. By rolling two balls (one above and one below the signal) of a suitable radius, the balls are large enough to roll over bruits and yet small enough to ride on heart sound waveforms. The high-frequency bruits can then be extracted according to a tangibility criterion by using the local extrema touched by the balls. Similarly, the low-frequency heart sounds can be acquired by a larger radius. By visualizing the periodicity information of both the extracted heart sounds and bruits, the proposed visual inspection method can potentially improve carotid bruit diagnosis accuracy.
authors.affiliation: Research Center for Adaptive Data Analysis, National Central University, Jhongli, 32001, Taiwan.
authors.forename: Adam
authors.initials: A
authors.lastname: Huang
authors.affiliation: Department of Medical Imaging, National Taiwan University Hospital, Taipei, 100, Taiwan.
authors.forename: Chung-Wei
authors.initials: CW
authors.lastname: Lee
authors.affiliation: Department of Medical Imaging, National Taiwan University Hospital, Taipei, 100, Taiwan.|Department of Radiology, College of Medicine, National Taiwan University, Taipei, 100, Taiwan.
authors.forename: Hon-Man
authors.initials: HM
authors.lastname: Liu
mesh_terms: D000465:Algorithms; D050197:Atherosclerosis / Q000503:physiopathology; D002339:Carotid Arteries / Q000502:physiology*; D003251:Constriction, Pathologic / Q000503:physiopathology; D006321:Heart / Q000502:physiology*; D006326:Heart Auscultation / Q000379:methods; D006801:Humans; D012039:Regional Blood Flow / Q000502:physiology; D013016:Sound