Biomechanical characterization of blood vessel and plaque from intravascular ultrasound images

摘要

The elastic properties of arteries and plaque are difficult to assess due to the technical problems associated with obtaining the required dimensional and stress parameters in vivo. This paper describes a method to determine the biomechanical properties of blood vessels and plaque based on dimensional information obtained from the analysis of intravascular ultrasound images. As a pilot study, two models of a stenotic artery were made that included an eccentric, flexible plaque of known size. These models were submerged in water and imaged at up to 15 axial locations over a static pressure range from 0 to 200 mmHg. Plaque and wall borders were automatically detected using a heuristic graph searching technique. Cross-sectional area changes, dimensional parameters and elastic properties were determined for each location and intraluminal pressure. The incremental elastic modulus of the tube wall was within 8% of the value determined from micrometer measurements. Plaque stiffness was close to that of a fibrous arterial plaque. Cross-sectional changes indicated a radial expansion of the compliant plaque with pressure.