Ultrasound saline infused sonohysterography based in-vivo strain imaging for the evaluation of uterine abnormalities

We demonstrate the feasibility of ultrasound saline infused sonohysterography based strain imaging, for the determination of variations in the stiffness of uterine masses in-vivo. Strain images are estimated using a two-dimensional multilevel hybrid algorithm developed for ultrasound sector array transducers. Coarse displacements are initially estimated using envelope data, followed by guided finer displacement estimation using window lengths on the order of 4 wavelengths and 5A-lines on RF data. Strain images are obtained by estimating displacement slopes using least squares estimation. The strain images provide additional new information that may supplement current clinical B-mode imaging, used for diagnosis of uterine abnormalities. Stiffer masses such as fibroids are clearly differentiated on the strain images, which appear to be darker on the strain images with the characteristic decorrelation "halo" when compared to the normal uterine tissue. In addition, uterine polyps are visualized with a lighter grayscale when compared to the background myometrium, indicating the presence of a softer mass. Our results demonstrate the feasibility of improving clinical diagnosis based on strain imaging.