Document Detail

A rotating torus phantom for assessing color Doppler accuracy.
MedLine Citation:
PMID:  10576268     Owner:  NLM     Status:  MEDLINE    
A rotating torus phantom was designed to assess the accuracy of color Doppler ultrasound. A thin rubber tube was filled with blood analog fluid and joined at the ends to form a torus, then mounted on a disk submerged in water and rotated at constant speeds by a motor. Flow visualization experiments and finite element analyses demonstrated that the fluid accelerates quickly to the speed of the torus and spins as a solid body. The actual fluid velocity was found to be dependent only on the motor speed and location of the sample volume. The phantom was used to assess the accuracy of Doppler-derived velocities during two-dimensional (2-D) color imaging using a commercial ultrasound system. The Doppler-derived velocities averaged 0.81 +/- 0.11 of the imposed velocity, with the variations significantly dependent on velocity, pulse-repetition frequency and wall filter frequency (p < 0.001). The torus phantom was found to have certain advantages over currently available Doppler accuracy phantoms: 1. It has a high maximum velocity; 2. it has low velocity gradients, simplifying the calibration of 2-D color Doppler; and 3. it uses a real moving fluid that gives a realistic backscatter signal.
S F Stewart
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Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Ultrasound in medicine & biology     Volume:  25     ISSN:  0301-5629     ISO Abbreviation:  Ultrasound Med Biol     Publication Date:  1999 Oct 
Date Detail:
Created Date:  1999-12-07     Completed Date:  1999-12-07     Revised Date:  2000-12-18    
Medline Journal Info:
Nlm Unique ID:  0410553     Medline TA:  Ultrasound Med Biol     Country:  ENGLAND    
Other Details:
Languages:  eng     Pagination:  1251-64     Citation Subset:  IM    
Hydrodynamics and Acoustics Branch, Center for Devices and Radiological Health, Food and Drug Administration, Rockville, MD 20850, USA.
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MeSH Terms
Blood Flow Velocity*
Image Processing, Computer-Assisted
Phantoms, Imaging*
Reproducibility of Results
Ultrasonography, Doppler, Color*

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

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