Vascular Research
Accurate assessment of vascular health is critical for detecting and treating many conditions including stroke, vascular disease, diabetes, cardiovascular disease, peripheral vascular occlusive disease, and renal failure. Epsilon Imaging's technology using ultrasound and RF-based speckle tracking may be useful for directly measuring artery stiffness, or compliance, which has been shown to be a sensitive indicator of developing vascular pathologies. Motion and deformation measures of vessel tissues may provide quantification of artery mechanical properties non-invasively. In addition, Epsilon Imaging is investigating novel vessel pressure equalization techniques to provide enhanced sensitivity and allow for complete characterization of the non-linear elastic modulus.
Two examples of arterial ultrasound imaging and tissue motion measurements from Epsilon's research are shown below.
(Click on the four arrows in the lower right corner for full screen)
Figure presents an example of blood vessel motion and deformation measurements derived from RF-based speckle tracking.
Left panel: B-mode image loop of healthy brachial artery and surrounding tissue. With the image plane orthogonal to the vessel axis. The vessel was pressure equalized to enhance blood pulse induced motion and to provide measurement of the non-linear elastic properties. Coloring of the vessel wall represents regional circumferential strain, with brighter green corresponding to increased strain.
Right panel: Quantification of vessel wall circumferential strain through cardiac cycle. Peak of curve describes time and degree of maximum expansion. The technology provides clear visualization and quantification of vessel wall stretching.
Figure shows an example of measuring the regional mechanical properties of a brachial artery wall.
Left panel: Tissue velocity image (red/blue colors) superimposed on B-mode image near state of maximum expansion. Vessel wall is colored (green/brown shades) to indicate regional circumferential strain (wall stretching).
Right panel: Color M-mode display of circumferential strain along the vessel wall throughout the cardiac cycle, describing the spatial variation in wall expansion/contraction.