In-vivo ultrasound data
The data was obtained from a healthy 33 years old male. The audio data
was sampled for both the reverse and forward flow. The data for the measurements
are given below:
| Ultrasound scanner: |
B-K Medical A/S type 3535 |
| Scan mode: |
Duplex |
| Transducer: |
B-K 8556, 3.2 MHz linear array probe |
| B-mode gain: |
38% |
| Range gate: |
2 mm |
| Duration: |
10.26 s or 10.52 s |
| Sampling frequency: |
8 kHz |
| Resolution: |
16 bits samples |
| Range: |
2^15 corresponds to 1 volt |
| Sampled: |
Forward and reverse flow signals |
The audio data can be obtained from the web-server from the directory:
https://courses.healthtech.dtu.dk/22485/files/ult_data/in-vivo/audio/
The following measurements were made:
| Place |
File name |
PRF |
Depth |
Angle |
Wall filter |
| Carotis, transverse scan |
car_tran2 (wav)
(mat) |
5 kHz |
2.1 cm |
52° |
4.2 cm/s |
| Carotis, transverse scan |
car_tran3 (wav)
(mat) |
5 kHz |
2.1 cm |
52° |
4.2 cm/s |
| Carotis, longitudinal scan |
car_long1 (wav)
(mat) |
6 kHz |
2.1 cm |
60° |
5.2 cm/s |
| Hepatic vein, longitudinal scan |
hepa_long1 (wav)
(mat) |
2.5 kHz |
4.6 cm |
12° |
2.6 cm/s |
| Portal vein, longitudinal scan |
porta_long1 (wav)
(mat) |
2.5 kHz |
6.2 cm |
66° |
6.5 cm/s |
| Aorta, longitudinal scan |
aorta_long1 (wav)
(mat) |
5 kHz |
5.5 cm |
67° |
6.3 cm/s |
| Aorta, transverse scan |
aorta_tran1 (wav)
(mat) |
5 kHz |
6.1 cm |
66° |
6.5 cm/s |
Both the raw audio data as a wave file can be found (under the (wav)
field in the table), along with the complex audio data in a Matlab file
(under the (mat) field in the table). The last file can be directly read
and manipulate with Matlab. The variable complex_data contains the
complex data, forward is the forward flow signal, and reverse
is the reverse flow signal. The wave file can be read by the command wavread
in Matlab 5.1 and higher. Note that this does not work in Matlab 5.0, due to a bug
in wavread.
PRF is short hand for pulse repetition frequency, Depth is the distance
from the transducer to the range gate center, and Angle indicates the angle
between the ultrasound beam and the vessel. Wall filter is the cut-off
used by the scanner for removing the clutter signal.
Note that the sampling frequency of the digital data is different from
the pulse repetition frequency PRF. This is because the digital data was
sampled from the scanner's analog output. The velocity range is only determined
by PRF.
| 
Print Version