title: High-resolution ultrasound speckle tracking may detect vascular mechanical wall changes in peripheral artery bypass vein grafts.
abstract: We report the use of high-resolution, phase-sensitive ultrasound speckle tracking to measure the local vessel-wall strain in two subjects with artery-vein bypass grafts. In addition, we combined this technique with a free-hand pressure equalization procedure to elucidate the nonlinear effects of blood pressure on vessel wall compliance. While conventional ultrasound imaging can be used to elucidate the mechanical properties of tissues within the body, it is constrained by comparatively lower resolution and inferential, rather than direct, measurements of strain and by the small strain normally produced under physiological pressure in highly nonlinear structures such as arteries. One of our subjects was examined both before and after developing stenosis 3 months postsurgery. The strain values for this individual were found to be significantly lower, indicating a stiffer vessel wall at the stenotic region than at a nonstenotic region under both physiological and equalized pressure. These results suggest the possibility of noninvasive detection of neointimal hyperplasia preceding anastomotic stenosis.
authors.affiliation: Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109-5725, USA. weitzel@umich.edu
authors.forename: William F
authors.initials: WF
authors.lastname: Weitzel
authors.forename: Kang
authors.initials: K
authors.lastname: Kim
authors.forename: Peter K
authors.initials: PK
authors.lastname: Henke
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Rubin
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001794:Blood Pressure; D003187:Compliance; D003251:Constriction, Pathologic; D054459:Elasticity Imaging Techniques; D005240:Feasibility Studies; D005263:Femoral Artery / Q000000981:diagnostic imaging* / Q000601:surgery; D006083:Graft Occlusion, Vascular / Q000000981:diagnostic imaging* / Q000209:etiology / Q000503:physiopathology; D006801:Humans; D008297:Male; D016491:Peripheral Vascular Diseases / Q000000981:diagnostic imaging / Q000601:surgery*; D011150:Popliteal Artery / Q000000981:diagnostic imaging* / Q000601:surgery; D011237:Predictive Value of Tests; D013314:Stress, Mechanical; D014656:Vascular Surgical Procedures / Q000009:adverse effects*; D014680:Veins / Q000000981:diagnostic imaging* / Q000601:surgery