Annie Delouche

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BACKGROUND To evaluate hemodynamic and functional changes of the failed left ventricle by Velocity Vector Imaging (VVI) and tissue Doppler, 22 patients with cardiogenic shock supported by extracorporeal life support (ECLS) were imaged during ECLS output variations inducing severe load manipulations. METHODS The following data were acquired: (1) mean(More)
BACKGROUND Factor analysis of the left ventricle in echography was developed to study the regional wall motion. Two factors and associated factor images were estimated using specific constraints: one "constant" factor and another "contraction-relaxation" factor. The constant factor was encoded in green, the positive component of the contraction in red and(More)
Acceleration mapping can be conducted by replacing the bipolar gradient pulse of a velocity mapping sequence by a tripolar pulse. However, since the acceleration encoding pulse is longer, the image quality is altered by the requirement of a long echo time. Since Fourier encoding velocity imaging has been shown to be robust, this velocity mapping method was(More)
The computerized study of the regional contraction of the left ventricle has undergone numerous developments, particularly in relation to echocardiography. A new method, parametric analysis of main motion (PAMM), is proposed in order to synthesize the information contained in a cine loop of images in parametric images. PAMM determines, for the intensity(More)
A class of adapted mean frequency estimators is proposed for color flow mapping. These estimators can be fitted to the specific characteristics of a given Doppler signal to optimize the compromise between the range of analysable frequencies and the variance of mean frequency estimation. A sub-optimal estimator is derived for real-time applications, and an(More)
BACKGROUND Color Doppler and magnetic resonance imaging give pictures of abnormal jets within which the respective contribution of fluid mechanics and image artifacts are difficult to establish because of current technical limitations of these modalities. We conducted the present study to provide numerical descriptions of the velocity fields within(More)
This study has tested solutions to optimize the ability of factor analysis of the left ventricle in echocardiography (FALVE) to detect segmental wall motion abnormalities automatically. On four- and two-chamber views of 38 patients, two factors (one flat curve and one curve describing the contraction-relaxation sequence) were extracted and associated factor(More)
Aortic insufficiency induces the development of a jet within the left ventricular outflow tract. The diameter of a laminar jet is a well-defined hydraulic parameter. This study was designed to evaluate, both experimentally and in patients, the accuracy of its measurement using a Doppler imaging performed with a multigate pulsed Doppler velocimeter. The(More)
The automatic detection of end diastole and end systole is the first step of any software developed for a fully automatic calculation of the ejection fraction. In this study, methods of image processing were applied to black and white echocardiographic image sequences corresponding to a cardiac cycle and the end systolic image number was automatically(More)