2018 JRNL PP Morten Smedsrud Wigen - 1.pdf?
Terbatas  Irwan Sofiyan
» Gedung UPT Perpustakaan
Terbatas  Irwan Sofiyan
» Gedung UPT Perpustakaan
In vivo characterization of intracardiac blood
velocity vector fields may provide new clinical information
but is currently not available for bedside evaluation. In this
paper, 4-D vector flow imaging for intracardiac flow assessment
is demonstrated using a clinical ultrasound (US)
system and a matrix array transducer, without the use of
contrast agent. Two acquisition schemes were developed,
one for full volumetric coverage of the left ventricle (LA) at
50 vps and a 3-D thick-slice setup with continuous frame
acquisition (4000 vps), both utilizing ECG-gating. The
3-D vector velocity estimates were obtained using a novel
method combining phase and envelope information. In vitro
validation in a rotating tissue-mimicking phantom revealed
velocity estimates in compliance with the ground truth,
with a linear regression slope of 0.80, 0.77, and 1.03 for the
x, y, and z velocity components, and with standard
deviations of 2.53, 3.19, and 0.95 cm/s, respectively. In vivo
measurements in a healthy LV showed good agreement
with PC-MRI. Quantitative analysis of energy loss (EL) and
kinetic energy (KE) further showed similar trends, with
peak KE at 1.5 and 2.4 mJ during systole and 3.6 and 3.1 mJ
for diastole for US and PC-MRI. Similar for EL, 0.15–0.2 and
0.7 mW was found during systole and 0.6 and 0.7 mW
during diastole, for US and PC-MRI, respectively. Overall,
a potential for US as a future modality for 4D cardiac vector
flow imaging was demonstrated, which will be further
evaluated in clinical studies.