A method for registration and model-based segmentation of Doppler ultrasound images

Morphological changes of Doppler ultrasound images are an important source of information for diagnosis of cardiovascular diseases. Quantification of these flow profiles requires segmentation of the ultrasound images. In this article, we propose a new model-based method for segmentation of (aortic outflow) velocity profiles. The method is based on a procedure for registration using a geometric transformation specifically designed for matching Doppler ultrasound profiles. Mutual information is used as an image similarity measure, while optimization is performed by a genetic algorithm. The registration method is experimentally validated using an in-silico image phantom. The model based segmentation is evaluated in a series of aortic outflow Doppler ultrasound images from 30 normal volunteers, comparing the automated method to the manual delineation by an expert cardiologist. The experimental results confirm the accuracy of the approach and shows that the method can be used for the segmentation of clinically obtained aortic outflow velocity profiles.