Abstract FR:

The work of this thesis deals with tissue elasticity imaging with ultrasound, also called elastography. The principle of the method is to estimate, by signal and image processing, the displacement or strain that appears in a tissue when it is mechanically compressed. This work proposes a displacement vector estimation method between two ultrasound images based on the search of the zero crossing of the complex correlation between signals taken in the ultrasound image. The image formation is adapted to the requirements of the estimator and an impulse response showing oscillations in both directions of the image is synthesized. The quality of the estimated displacement maps is highly increased thanks to the use of this impulse response. Simulation and experimental results acquired with a Danish research ultrasound scanner illustrate the work.