Title 
Estimation of blood velocities with ultrasound 
Author

Lacasa, Isobel Rodíguez

Supervisor

Jensen, Jørgen Arendt (Biomedical Engineering, Department of Electrical Engineering, Technical University of Denmark, DTU, DK2800 Kgs. Lyngby, Denmark)

Institution 
Technical University of Denmark, DTU, DK2800 Kgs. Lyngby, Denmark 
Thesis level 
Master's thesis 
Year 
1999 
Abstract 
The measurement of blood flow is essential in the diagnosis of most vascular diseases.
Modern ultrasound scanners find only the axial velocity of blood i.e. the velocity component
parallel to the ultrasound beam. Therefore, when estimating the blood flow rate, physicians need
to emit hypothesis. They have to estimate the angle, between the vessel studied and the ultrasound
beam, and to estimate whether the flow is steady or disturbed. This proves that the measurement
of the complete velocity vector will be of great interest since flow reconstruction will become an
objective measure.
The work developed in this thesis was focussed on finding a scanning method which allows the
estimation of the transverse component of blood velocity. The point of departure was a work
developed by Bonnefus [1] ten years ago. This work suggests the use of multiple parallel beams
in reception for each pulse emission, and a crosscorrelation estimation method for finding the
transverse velocity component. A new approach was then developed. This was the calculation
of a transverse beam that track the transverse motion of blood flow. Simulations were made that
gave satisfactory results in the case of a blunt velocity profile. The idea of a lateral beam was then
extended to several beams in the direction of blood flow. Satisfactory results were then obtained
for parabolic profiles. The angle is again to be set by physicians, but the result is the complete
velocity vector estimation. 
Pages 
105 
Admin 
Creation date: 20090625
Update date: 20090625
Source: dtu
ID: 245554
Original MXD
