## Files in this item

FilesDescriptionFormat

application/pdf

9124423.pdf (9MB)
(no description provided)PDF

## Description

 Title: Measurement of volumetric blood flow using ultrasound time-domain correlation Author(s): Hein, Ilmar Arthur Doctoral Committee Chair(s): O'Brien, William D. Department / Program: Electrical and Computer Engineering Discipline: Electrical and Computer Engineering Degree Granting Institution: University of Illinois at Urbana-Champaign Degree: Ph.D. Genre: Dissertation Subject(s): Engineering, Biomedical Engineering, Electronics and Electrical Biophysics, Medical Abstract: The Ultrasound Time Domain Correlation (UTDC) technique can accurately and precisely estimate the volumetric fluid flow through a circular vessel without prior knowledge of the vessel diameter, flow velocity profile, or transducer measurement angle. This technique observes the change in arrival time (instead of frequency, as with Doppler techniques) of ultrasound reflected from scatterers. If a vessel with moving fluid is insonated by two ultrasonic pulses separated by time T, the scatterers within the ultrasonic beam will move some distance D between the first and second pulse. There will be a difference $\tau$ in the arrival times of the two pulses since the scatterer has moved. The scatterer velocity can be calculated from the time difference $\tau$. By sampling the velocity at different positions along the vessel, the transducer measurement angle and the volumetric flow can be calculated.Previous research has shown that this technique can estimate the volumetric flow rate of constant, fully developed laminar flow in a blood flow phantom with an accuracy of 15%. This dissertation represents continuing development of the UTDC technique towards the eventual goal of producing a clinical quantitative blood flowmeter. Blood flow phantom measurements have been made in conditions more closely resembling in vivo conditions, such as pulsatile flow, multiple vessels, different size vessels, and attenuation. A real-time UTDC blood flowmeter system interfaced to a commercial ultrasound imager has been constructed and in vivo measurements have been made in canines and humans. Issue Date: 1991 Type: Text Language: English URI: http://hdl.handle.net/2142/22603 Rights Information: Copyright 1991 Hein, Ilmar Arthur Date Available in IDEALS: 2011-05-07 Identifier in Online Catalog: AAI9124423 OCLC Identifier: (UMI)AAI9124423
﻿