Ultrasound measurement of brachial flow-mediated vasodilator response

• Published in: IEEE transactions on medical imaging Vol. 19; no. 6; pp. 621 - 631
• Main Authors: Liexiang Fan, Santago, P., Huai Jiang, Herrington, D.M.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.06.2000; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Adult; Arteries; Automation; Biological and medical sciences; Blood Flow Velocity - physiology; Brachial Artery - diagnostic imaging; Brachial Artery - physiology; Brachytherapy; Cardiovascular system; Computerized monitoring; Deformable models; Female; Humans; Image Processing, Computer-Assisted; Interference; Investigative techniques, diagnostic techniques (general aspects); Male; Medical sciences; Noise robustness; Observer Variation; Reproducibility of Results; Spatiotemporal phenomena; Ultrasonic imaging; Ultrasonic investigative techniques; Ultrasonic variables measurement; Ultrasonography; Vasodilation - physiology; Veins & arteries; Sonography; Human; Deformability; Brachial artery; Transient flow; Geometrical model; Vasodilation; Automatic measurement; Dimensional analysis; Circulatory system; Hemodynamics; Diameter; Monitoring
• ISSN: 0278-0062; 1558-254X
• DOI: 10.1109/42.870669

Brachial artery flow-mediated vasodilation is increasingly used as a measure of endothelial function. High resolution ultrasound provides a noninvasive method to observe this flow-mediated vasodilation by monitoring the diameter of the artery over time following a transient flow stimulus. Since hundreds of ultrasound images are required to continuously monitor brachial diameter for the 2-3 min during which the vasodilator response occurs, an automated diameter estimation is desirable. However, vascular ultrasound images suffer from structural noise caused by the constructive and destructive interference of the backscattered signals, and the true boundaries of interest that define the diameter are frequently obscured by the multiple-layer structure of the vessel wall. These problems make automated diameter estimation strategies based on the detection of the vessel wall boundary difficult. The authors obtain a robust automated measurement of the vasodilator response by automatically locating the artery using a variable window method, which gives both the lumen center and width. The vessel wall boundary is detected by a global constraint deformable model, which is insensitive to the structural noise in the boundary area. The ambiguity between the desired boundary and other undesired boundaries is resolved by a spatiotemporal strategy. The authors' method provides excellent reproducibility both for interreader and intrareader analyzes of percent change in diameter, and has been successfully used in analyzing over 4000 brachial flow-mediated vasodilation scans from several medical centers in the United States.