| The potential of intravascular ultrasound imaging for characterizing regional arterial elasticity was examined in an experimental tissue equivalent vessel model. The feasibility of differential intra-wall displacement measurement, the first step in regional elasticity determination, was investigated using a cross-correlation tracking algorithm. Displacement was tracked in serial intravascular images of vessels acquired during static, stepwise pressurization experiments from 0-250 mmHg. Two-dimensional grey scale maps of intra-wall displacement components over the full pressurization range were generated. Displacement profiles demonstrated successful detection of differential radial displacement and good correlation with theoretical profiles (root mean square difference 3%). The corresponding experimental strain profiles were significantly noisier (root mean square difference 76%) due to small fluctuations in the displacement data. This work demonstrates that, with further refinement, regional strain mapping in vessel walls with intravascular ultrasound imaging is feasible. Mechanical characterization of arteries may provide a new tool to aid in assessing and treating of atherosclerotic lesions. |
