Multiresolution Cube Propagation for 3-D Ultrasound Image Reconstruction

Three-dimensional (3-D) ultrasound provides physicians with volume rendering of patient ultrasound data. This medical ultrasound technique carries important clinical value in image-guided surgery. However, 3-D ultrasound is not widely used because obtaining 3-D ultrasound images is difficult and costly, and the technology used is incapable of scanning large-volume organs. This paper proposes a novel method for 3-D freehand ultrasound reconstruction, which can accurately restore 3-D volumes from 2-D B-scans through cube propagation. The 3-D multi-resolution method creates a 3-D volume pyramid and a 3-D texture pyramid to preserve the structural and textural details of the imaged volume. Computation efficiency is improved with the 3-D approximate nearest neighbors (ANN) search technique, which is proposed to accelerate the nearest-neighbor search through the whole 3-D ultrasound volume. Texture information in the texture pyramid is added to the cube distance in the nearest-neighbors searching step to identify suitable nearest neighbors. Experiments performed on clinical and synthetic datasets demonstrate that the proposed algorithm is robust and can achieve quality results in a short execution time relative to current reconstruction techniques.