title: Ultrasonic anisotropy measured in 2-dimensional echocardiograms in vitro and verified by histology.
abstract: This study aims to validate ultrasonic anisotropy in 2-dimensional echocardiograms by one-to-one histological correlation. Thirteen echograms were obtained in vitro from 9 specimens of 2 left ventricles of healthy adult beagle dogs and were correlated with corresponding histology in regard to ultrasound orientation relative to the local fiber direction. Median value of pixel echogenicity (255-rank) was lower in areas with parallel (n = 9, 18 ± 13) than in those with oblique (n = 7, 41 ± 14, P < 0.05) and perpendicular (n = 13, 57 ± 21, P < 0.01) ultrasound orientations. Echogenicity in the proximal part within 0.5 cm from an edge was relatively high (n = 9, 33 ± 15; n = 5, 66 ± 27; n = 8, 65 ± 32, respectively) and was different between parallel and perpendicular orientations (P < 0.05). The ratio of the distal adjacent 0.5-cm part to the proximal part echogenicity was lower for either parallel or oblique orientation (0.35 ± 0.25, 0.51 ± 0.16) than for perpendicular orientation (0.95 ± 0.16, P < 0.01, respectively). Acoustic dropouts appeared beyond myocardial areas with parallel or oblique ultrasound orientation. These results disclosed precise acoustic anisotropy in the 2-dimensional echocardiograms.
authors.affiliation: Department of Biofunctional Informatics, Graduate School of Health Care Sciences, Tokyo Medical and Dental University.
authors.forename: Junko
authors.initials: J
authors.lastname: Komata
authors.forename: Tokuhiro
authors.initials: T
authors.lastname: Kawara
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Tanaka
authors.forename: Sera
authors.initials: S
authors.lastname: Hirota
authors.forename: Sayaka
authors.initials: S
authors.lastname: Nishi
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Cho
authors.forename: Kenji
authors.initials: K
authors.lastname: Sato
authors.forename: Masato
authors.initials: M
authors.lastname: Matsuura
authors.forename: Itsuro
authors.initials: I
authors.lastname: Miyazato
mesh_terms: D000818:Animals; D016880:Anisotropy; D004285:Dogs; D004452:Echocardiography / Q000379:methods*; D006346:Heart Septum / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D006352:Heart Ventricles / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D007091:Image Processing, Computer-Assisted / Q000379:methods; D009206:Myocardium / Q000166:cytology; D009210:Myofibrils / Q000000981:diagnostic imaging; D010210:Papillary Muscles / Q000033:anatomy & histology / Q000000981:diagnostic imaging