title: Improved tracking performance of Lagrangian block-matching methodologies using block expansion in the time domain: in silico, phantom and in vivo evaluations.
abstract: The aim of this study was to evaluate tracking performance when an extra reference block is added to a basic block-matching method, where the two reference blocks originate from two consecutive ultrasound frames. The use of an extra reference block was evaluated for two putative benefits: (i) an increase in tracking performance while maintaining the size of the reference blocks, evaluated using in silico and phantom cine loops; (ii) a reduction in the size of the reference blocks while maintaining the tracking performance, evaluated using in vivo cine loops of the common carotid artery where the longitudinal movement of the wall was estimated. The results indicated that tracking accuracy improved (mean = 48%, p < 0.005 [in silico]; mean = 43%, p < 0.01 [phantom]), and there was a reduction in size of the reference blocks while maintaining tracking performance (mean = 19%, p < 0.01 [in vivo]). This novel method will facilitate further exploration of the longitudinal movement of the arterial wall.
authors.affiliation: Department of Biomedical Engineering, Lund University, Lund, Sweden. Electronic address: john.albinsson@bme.lth.se.
authors.forename: John
authors.initials: J
authors.lastname: Albinsson
authors.affiliation: School of Business and Engineering, PRODEA Research Group, Halmstad University, Halmstad, Sweden; Health and Welfare, Dala Sports Academy, Dalarna University, Falun, Sweden.
authors.forename: Sofia
authors.initials: S
authors.lastname: Brorsson
authors.affiliation: Clinical Physiology and Nuclear Medicine Unit, Department of Clinical Sciences, Lund University, Malmo, Sweden.
authors.forename: Asa Rydén
authors.initials: AR
authors.lastname: Ahlgren
authors.affiliation: Department of Biomedical Engineering, Lund University, Lund, Sweden.
authors.forename: Magnus
authors.initials: M
authors.lastname: Cinthio
mesh_terms: D000465:Algorithms; D017536:Carotid Artery, Common / Q000000981:diagnostic imaging* / Q000502:physiology; D003198:Computer Simulation; D007091:Image Processing, Computer-Assisted / Q000379:methods; D009068:Movement / Q000502:physiology; D019047:Phantoms, Imaging; D014463:Ultrasonography / Q000379:methods*
keywords: Arterial wall movement; Longitudinal movement; Motion estimation; Speckle tracking; Ultrasound