The goal of this proposal is to develop, analyze, and test an innovative technique for measuring volume blood flow ultrasonically. The quantification of volumetric flow is useful for a number of clinical applications including estimation of cardiac output, monitoring of cerebrovascular diseases, and evaluation of intrauterine growth restriction (IUGR) during pregnancy. Current techniques for measuring volumetric flow are either invasive (i.e. insertion of a Swan-Ganz catheter) or have limited accuracy (i.e. calculations based on Doppler measurements). The long term goal of this project is to defme a real-time, angle-independent volumetric flow measurement technique that can be implemented with current clinical scanner architecture. The proposed algorithm incorporates steered Doppler with the decorrelation of the raw ultrasound RF signals to compute the 3-D vector velocity profile of a vessel using a single transducer. Integration of the normal flow component over a cross-section of the vessel provides the total volume flow. This study will test implementation using modified pulsing sequences and digital correlators currently used in standard Doppler ultrasound machines. The algorithm will initially be verified on steady flow of blood-mimicking fluids in phantoms. A permutation test will be used to determine optimal parameter settings and ifitering schemes. Pulsatile waveforms and velocities in physiological ranges will be examined for accuracy and temporal resolution. Validation of the technique in vivo will be done by measuring flow in canine arteries and comparing with electromagnetic flow cuff results. Final evaluation of the technique will involve a pilot study quantifying flow in grafts of human subjects undergoing dialysis.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
5R01HL067921-02
Application #
6527770
Study Section
Diagnostic Imaging Study Section (DMG)
Program Officer
Buxton, Denis B
Project Start
2001-09-20
Project End
2004-07-31
Budget Start
2002-08-01
Budget End
2003-07-31
Support Year
2
Fiscal Year
2002
Total Cost
$255,483
Indirect Cost
Name
University of Michigan Ann Arbor
Department
Radiation-Diagnostic/Oncology
Type
Schools of Medicine
DUNS #
791277940
City
Ann Arbor
State
MI
Country
United States
Zip Code
48109
Pinter, Stephen Z; Rubin, Jonathan M; Kripfgans, Oliver D et al. (2012) Three-dimensional sonographic measurement of blood volume flow in the umbilical cord. J Ultrasound Med 31:1927-34
Richards, Michael S; Kripfgans, Oliver D; Rubin, Jonathan M et al. (2009) Mean volume flow estimation in pulsatile flow conditions. Ultrasound Med Biol 35:1880-91
Kripfgans, Oliver D; Rubin, Jonathan M; Hall, Anne L et al. (2006) Measurement of volumetric flow. J Ultrasound Med 25:1305-11
Kripfgans, Oliver D; Rubin, Jonathan M; Hall, Anne L et al. (2006) Vector Doppler imaging of a spinning disc ultrasound Doppler phantom. Ultrasound Med Biol 32:1037-46