Global left ventricular function in cardiac CT. Evaluation of an automated 3D region-growing segmentation algorithm.
The purpose was to evaluate a new semi-automated 3D region-growing segmentation algorithm for functional analysis of the left ventricle in multislice CT (MSCT) of the heart. Twenty patients underwent contrast-enhanced MSCT of the heart (collimation 16 x 0.75 mm; 120 kV; 550 mAseff). Multiphase image reconstructions with 1-mm axial slices and 8-mm short-axis slices were performed. Left ventricular volume measurements (end-diastolic volume, end-systolic volume, ejection fraction and stroke volume) from manually drawn endocardial contours in the short axis slices were compared to semi-automated region-growing segmentation of the left ventricle from the 1-mm axial slices. The post-processing-time for both methods was recorded. Applying the new region-growing algorithm in 13/20 patients (65%), proper segmentation of the left ventricle was feasible. In these patients, the signal-to-noise ratio was higher than in the remaining patients (3.2+/-1.0 vs. 2.6+/-0.6). Volume measurements of both segmentation algorithms showed an excellent correlation (all P<or=0.0001); the limits of agreement for the ejection fraction were 2.3+/-8.3 ml. In the patients with proper segmentation the mean post-processing time using the region-growing algorithm was diminished by 44.2%. On the basis of a good contrast-enhanced data set, a left ventricular volume analysis using the new semi-automated region-growing segmentation algorithm is technically feasible, accurate and more time-effective.
Mühlenbruch
Georg
G
Department of Diagnostic Radiology, University Hospital RWTH Aachen, Pauwelsstrasse 30, 52057 Aachen, Germany. gmuehlen@rad.rwth-aachen.de
Das
Marco
M
Hohl
Christian
C
Wildberger
Joachim E
JE
Rinck
Daniel
D
Flohr
Thomas G
TG
Koos
Ralf
R
Knackstedt
Christian
C
Günther
Rolf W
RW
Mahnken
Andreas H
AH
D000368:Aged; D000465:Algorithms; D002306:Cardiac Volume; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging / Q000503:physiopathology; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000503:physiopathology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D010363:Pattern Recognition, Automated; D013318:Stroke Volume; D014057:Tomography, X-Ray Computed; D016277:Ventricular Function, Left