Quantification of blood velocity from time-resolved CT angiography on a 256-slice CT
Host Publication: ECR 2018 - BOOK OF ABSTRACTS
Authors: P. Boonen, N. Buls, J. Vandemeulebroucke, G. Van Gompel, D. Aerden and J. De Mey
Publication Date: Feb. 2018
Purpose: To quantify the blood velocity in the arteries of the lower extremities
and to investigate the correlation with peripheral arterial disease (PAD).
Methods and Materials: 7 Patients with suspicion of PAD underwent timeresolved
Computed Tomography Angiography (CTA) in addition to their
standard run-off CTA, consisting of 18 repeated axial acquisitions at 2s
interphase delay at the level of the calves with 16cm collimation (Revolution
CT, GE Healthcare). Image data was processed using in-house developed
processing tools. Motion during the acquisitions was compensated by applying
registration, after which the anterior tibial artery, posterior tibial artery and
peroneal artery were automatically segmented by identifying large intensity
changes over time. Subsequently, blood velocity was quantified in the arteries
by creating time attenuation curves (TAC) of the arterial cross-sections in every
slice and determining the time to peak (TTP).
Results: The described method led to plausible velocity estimations in all
arteries (n=18) for patients that were considered healthy (n=3). For
pathological patients (n=4), only 12 out of 22 arteries could be quantified due to
suboptimal bolus arrival, severe calcification or occlusions. For arteries of
healthy patients, blood velocity was normally distributed (p=0.282) with a
median value of 82.3 mm/s (95% CI= 55.5- 89.9 mm/s). Blood velocity in
arteries of pathological patients was observed to be significantly lower, 30.7
mm/s (95% CI= 27.4ᇁ.7 mm/s), p<0.01.
Conclusion: Time-resolved CT data allows to quantify blood velocity in the
arteries of the lower extremities. In heavily occluded arteries, the contrast was
insufficient in order to quantify velocity.