title: Automated septum thickness measurement--a Kalman filter approach.
abstract: Interventricular septum thickness in end-diastole (IVSd) is one of the key parameters in cardiology. This paper presents a fast algorithm, suitable for pocket-sized ultrasound devices, for measurement of IVSd using 2D B-mode parasternal long axis images. The algorithm is based on a deformable model of the septum and the mitral valve. The model shape is estimated using an extended Kalman filter. A feasibility study using 32 unselected recordings is presented. The recordings originate from a database consisting of subjects from a normal healthy population. Five patients with suspected hypertrophy were included in the study. Reference B-mode measurements were made by two cardiologists. A paired t-test revealed a non-significant mean difference, compared to the B-mode reference, of (mean±SD) 0.14±1.36 mm (p=0.532). Pearson's correlation coefficient was 0.79 (p<0.001). The results are comparable to the variability between the two cardiologists, which was found to be 1.29±1.23 mm (p<0.001). The results indicate that the method has potential as a tool for rapid assessment of IVSd.
authors.affiliation: Department of Circulation and Medical Imaging, Norwegian University of Science and Technology (NTNU), and Department of Cardiology, St. Olavs University Hospital, Trondheim, Norway. sten.r.snare@ntnu.no
authors.forename: Sten Roar
authors.initials: SR
authors.lastname: Snare
authors.forename: Ole Christian
authors.initials: OC
authors.lastname: Mjølstad
authors.forename: Fredrik
authors.initials: F
authors.lastname: Orderud
authors.forename: Håvard
authors.initials: H
authors.lastname: Dalen
authors.forename: Hans
authors.initials: H
authors.lastname: Torp
mesh_terms: D000465:Algorithms; D001331:Automation; D006332:Cardiomegaly / Q000000981:diagnostic imaging* / Q000473:pathology; D016022:Case-Control Studies; D003971:Diastole; D005240:Feasibility Studies; D006346:Heart Septum / Q000033:anatomy & histology / Q000000981:diagnostic imaging* / Q000473:pathology; D006801:Humans; D008954:Models, Biological; D014463:Ultrasonography / Q000379:methods