Elevation direction deconvolution in three-dimensional ultrasound imaging

One-dimensional (1-D) linear transducer arrays can be used for three-dimensional (3-D) ultrasound image acquisition. However, the relatively low spatial resolution of these arrays in the elevation direction results in blurry 3-D images. Here, the authors introduce an elevation direction deconvolution (EDD) method that increases the spatial resolution of 3-D ultrasound images in the elevation direction. EDD is based on a deconvolution technique called power spectrum equalization. To evaluate the authors' method, Cartesian volumes were reconstructed with and without EDD from a series of two-dimensional (2-D) images of phantoms. Using these reconstructed volumes, the authors first evaluated the effect of EDD on elevation resolution by computing the full-width-at-quarter-maximum (FWQM) of peaks along lines of constant depth. They then evaluated the effect of EDD on the accuracy of volume calculation by computing the phantom's volumes. EDD decreased the FWQM of the peaks on elevation lines by an average of 17%; however, EDD did not significantly alter the accuracy of volume calculation. It is concluded that EDD can increase the spatial resolution in the elevation direction in 3-D ultrasound images and that EDD may improve the accuracy of volume calculation if a more consistent edge detection method is used.