Evaluation of the layered structure of aortic valve cusps using high-frequency ultrasound [bioprosthetic heart valve applications]

High-frequency ultrasound techniques are described for estimating the dimensions of the fibrosa, spongiosa, and ventricularis layers in aortic valve cusp specimens. Top flat and bottom hat transformations are applied to enhance the contrast of the layers in B-mode images. A modified discrete dynamic contour deformable model is implemented to detect the layer boundaries. The algorithm is demonstrated via measurements of osmotic swelling of the valve cusp layers produced by submerging the specimens in distilled water.