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