title: Rapid and accurate left ventricular surface generation from three-dimensional echocardiography by a catalog based method. Rapid LV surface generation by three-dimensional echo.
abstract: BACKGROUND
  Quantitative analysis from three-dimensional (3D) echocardiography requires accurate reconstruction of left ventricular (LV) surfaces. This currently requires time-consuming manual image tracing. We describe and validate an alternative rapid method of generating LV surfaces.
  
  
  METHODS
  A 3D-image set is acquired using transthoracic scanning. Images from five standard echo views are displayed and border points selected where anatomic landmarks are well defined. A LV surface is reconstructed as a convex weighted sum of LVs from a catalog of 80 LVs. The intersections of the surface with the five views are presented on these images. The routine may be rerun until the LV surface matches the images. One LV surface is generated in 3 min +/- 27 s. In 41 studies (19 normal, 15 previous infarction, seven cardiomyopathy) the volumes of the catalog-fit endocardial and epicardial surfaces were compared with volumes from surfaces reconstructed from full manual tracing.
  
  
  RESULTS
  Over a wide range of LV volumes and ejection fraction (EF), the catalog-fit results correlated closely to those from manual tracing: end-diastolic volume (194 +/- 99 vs. 204 +/- 110 ml, y = 0.93x, R2 = 0.99, SEE = 19 ml, p < 0.001), end-systolic volume (122 +/- 95 vs. 131 +/- 106 ml, y = 0.92x, R2 = 0.99, SEE = 13 ml, p < 0.001), EF (42 +/- 16 vs. 42 +/- 15%, y = x, R2 = 0.99, SEE = 4%, p < 0.001) and mass (220 +/- 88 vs. 204 +/- 86 g, y = 1.1x, R2 = 0.99, SEE = 24 g, p < 0.001). The endocardial catalog surface was generated from an average of 20 points and three computational runs for both end-diastole and end-systole.
  
  
  CONCLUSIONS
  The catalog method of LV reconstruction from 3D-echo provides accurate measurement of volume, EF and mass. The speed of the method is a major advantage.
authors.affiliation: Cardiac Imaging Laboratory, University of Washington, Seattle, WA, USA. spwong@middlemore.co.nz
authors.forename: Selwyn P
authors.initials: SP
authors.lastname: Wong
authors.forename: Richard K
authors.initials: RK
authors.lastname: Johnson
authors.forename: Florence H
authors.initials: FH
authors.lastname: Sheehan
mesh_terms: D019560:Echocardiography, Three-Dimensional; D006331:Heart Diseases / Q000000981:diagnostic imaging; D006352:Heart Ventricles / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D016277:Ventricular Function, Left / Q000502:physiology