This poster is published under an
open license. Please read the
disclaimer for further details.
Keywords:
Haemodynamics / Flow dynamics, Instrumentation, Ultrasound, Vascular
Authors:
M. Laganà1, M. Di Rienzo2, F. Rizzo2, L. Forzoni3, S. D'Onofrio3, P. Cecconi4; 1Milan/IT, 2Milano/IT, 3Firenze/IT, 4Como (CO)/IT
DOI:
10.1594/ecr2014/C-0223
Results
The average exam length for each subject was 25 minutes (including 5 minutes of subject’s rest before starting the US scanning).
The respiratory sensor was placed on the thorax left side in 2 subjects,
on the abdomen left side in 7 subjects and on the abdomen right side in 2 subjects.
Clear changes in the IJV and VV blood flow velocities were observed with the PW measures.
In particular,
the venous dynamics were synchronous with the breathing phases: in all the examined subjects,
blood flow velocities were higher during inspiration and lower during expiration (Fig.
2).
Conversely,
heart pulsation contributed to IJV velocity in 6 subjects and VV velocity in 6 subjects.
Fig.
2 shows two examples of PW trace with respiratory signal.
B-Mode and CD were used for PW SV positioning.
It is evident how the respiratory activity influences and it is perfectly synchronous with the blood flow in both cases,
while the heart pulsation evidenced by ECG seems to have a significant contribution only on the case on the right side.
In the two subjects where both ECG and respiratory sensors were placed,
the two signals were well detected,
without interference between them (Fig.
3).
Either in the B-Ref plus QDP visualization and in the QDP plus PW visualization,
the respiratory signal was displayed and it provided a tool for monitoring the PW SV position.
In the case shown in Fig.
4,
related to VV and Vertebral Artery (VA) examination,
QDP confirmed that the SV was in the correct position and the respiratory signal showed that the venous flow was synchronous with breathing.
Regarding the cerebral vein analysis,
no relevant differences related to the respiratory activity were detected on the BVR PW Doppler trace (Fig.
5).
The examination of the IJV valve with M-Mode and the simultaneous acquisition of the respiratory signal allowed an easier observation of the valve movements relative to the IJV vessel walls.
The valve moved exactly with the IJV vessel walls,
following the respiratory activity,
when it was fixed or with abnormal motility (Fig.
6),
while it moved independently in case of normal motility [18].
The Valsalva maneuver was well identified in images as a plateau of the respiratory signal,
in correspondence of which it was observed an increment of IJV area (Fig.
7) and a flow with constant and decreased velocity (Fig.
8).
The same was observed for VV flow,
while VV area did not change.