Rapid Hybrid Ultrasound Volume Registration

This work is concerned with registration of ultrasound volumes acquired using a mechanicallyswept 3D probe to produce extended-field-of-view images. While the registration can be achieved by attaching a position sensor to the probe, this can be an inconvenience in a clinical setting and aligns the volumes incorrectly if there is tissue motion due to subject movement or respiratory motion. The objective of this work is to replace the 6 degree of freedom (DOF) sensor with a combination of 3 DOF image registration and an unobtrusively integrated inertial sensor for measuring orientation. We aim to produce a highly reliable system that is able to register a pair of volumes very quickly, making it suitable for clinical use. As such, this is an extension of our previous work [1] and provides further results for a fast implementation of the Nelder-Mead simplex algorithm using reslices. Additionally, we provide some results for a voxel-array based multiresolution search algorithm. The multiresolution approach has a more complete coverage of the search space at the expense of speed and is more exhaustive in comparison to the Nelder-Mead Simplex algorithm. With similar reliability statistics for the two algorithms, both are possible candidates for a clinical system.