title: Fully automatic detection of salient features in 3-d transesophageal images.
abstract: Most automated segmentation approaches to the mitral valve and left ventricle in 3-D echocardiography require a manual initialization. In this article, we propose a fully automatic scheme to initialize a multicavity segmentation approach in 3-D transesophageal echocardiography by detecting the left ventricle long axis, the mitral valve and the aortic valve location. Our approach uses a probabilistic and structural tissue classification to find structures such as the mitral and aortic valves; the Hough transform for circles to find the center of the left ventricle; and multidimensional dynamic programming to find the best position for the left ventricle long axis. For accuracy and agreement assessment, the proposed method was evaluated in 19 patients with respect to manual landmarks and as initialization of a multicavity segmentation approach for the left ventricle, the right ventricle, the left atrium, the right atrium and the aorta. The segmentation results revealed no statistically significant differences between manual and automated initialization in a paired t-test (p > 0.05). Additionally, small biases between manual and automated initialization were detected in the Bland-Altman analysis (bias, variance) for the left ventricle (-0.04, 0.10); right ventricle (-0.07, 0.18); left atrium (-0.01, 0.03); right atrium (-0.04, 0.13); and aorta (-0.05, 0.14). These results indicate that the proposed approach provides robust and accurate detection to initialize a multicavity segmentation approach without any user interaction.
authors.affiliation: Laboratorio de Procesado de Imagen, ETS Ingenieros de Telecomunicación, Universidad de Valladolid, Valladolid, Spain; Thoraxcenter Biomedical Engineering, Erasmus University Medical Center, Rotterdam, The Netherlands. Electronic address: ariel@lpi.tel.uva.es.
authors.forename: Ariel H
authors.initials: AH
authors.lastname: Curiale
authors.affiliation: Department of Cardiology, Thoraxcenter, Erasmus University Medical Center, Rotterdam, The Netherlands.
authors.forename: Alexander
authors.initials: A
authors.lastname: Haak
authors.affiliation: Laboratorio de Procesado de Imagen, ETS Ingenieros de Telecomunicación, Universidad de Valladolid, Valladolid, Spain.
authors.forename: Gonzalo
authors.initials: G
authors.lastname: Vegas-Sánchez-Ferrero
authors.affiliation: Department of Cardiology, Thoraxcenter, Erasmus University Medical Center, Rotterdam, The Netherlands.
authors.forename: Ben
authors.initials: B
authors.lastname: Ren
authors.affiliation: Laboratorio de Procesado de Imagen, ETS Ingenieros de Telecomunicación, Universidad de Valladolid, Valladolid, Spain.
authors.forename: Santiago
authors.initials: S
authors.lastname: Aja-Fernández
authors.affiliation: Thoraxcenter Biomedical Engineering, Erasmus University Medical Center, Rotterdam, The Netherlands.
authors.forename: Johan G
authors.initials: JG
authors.lastname: Bosch
mesh_terms: D000368:Aged; D000465:Algorithms; D059925:Anatomic Landmarks / Q000000981:diagnostic imaging; D001021:Aortic Valve / Q000000981:diagnostic imaging*; D001185:Artificial Intelligence; D019560:Echocardiography, Three-Dimensional / Q000379:methods*; D017548:Echocardiography, Transesophageal / Q000379:methods*; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D008943:Mitral Valve / Q000000981:diagnostic imaging*; D010363:Pattern Recognition, Automated / Q000379:methods*; D012680:Sensitivity and Specificity
keywords: Active shape models; Gamma mixture model; Hough transform; Initialization; Multidimensional dynamic programming; Segmentation; Transesophageal echocardiography; Ultrasound