Freehand 3D ultrasound (US) consists in acquiring a US volume by moving a tracked conventional 2D probe over an
area of interest. To maintain good acoustic coupling between the probe and the skin, the operator applies pressure on the
skin with the probe. This pressure deforms the underlying tissues in a variable way across the excursion of the probe,
which, in turn, leads to inconsistencies in the volume. To address this problem, this paper proposes a method to estimate
the deformation field sustained by each image with respect to a reference deformation free image. The method is based
on a 2D biomechanical model that takes into account the mechanical parameters of the tissues depicted in the image to
predict a realistic deformation field. These parameters are estimated along with the deformation field such as to
maximize the mutual information between the reference and the corrected images. The image is then corrected by
applying the inverse deformation field. Preliminary validation was conducted with synthetic US images generated using
a 3D biomechanical model. Results show that the proposed method improves image correction compared to a purely
image-based method.
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