J Korean Radiol Soc.
1995 Aug;33(2):189-195.
Experimental Study on Representation of Flow on the Bifurcated Carotid Arterial Phantoms Using Magnetic Resonance Angiography
Abstract
- PURPOSE
A common finding of carotid artery on magnetic resonance angiograms(MRAs) is a signal dropout
along the posterior wall of carotid bulb due to reverse flow. The purpose of this study is to evaluate variable
flow patterns on bifurcated carotid arterial phantoms using steady-state flow.
MATERIALS AND METHODS
We designed phantoms of a bifurcated carotid artery with acrylic materials. Flow
patterns were evaluated with axial and coronal imaging of MRA(2D-TOF, 3D-TOF), color Doppler imaging, and
computational fluid dynamics (CFD) within the phantoms constructed of an automated closed-type circulatory
system filled with 4% sugar solution. These findings were compared with findings obtained from normal volunteers.
RESULTS
Axial 3D-TOF MRA images exhibited closer resemblance to the contour of the inner wall of
phantoms when compared to coronal 2D-TOF MRA imaging. However, 2D-TOF MRA showed good contrast difference
of signal intensities between forward flow area and reverse flow area. Dark zones with reduced signal
intensities due to reversed flow were separated from the outer wall of the internal and external carotid arteries
by a thin layer of forward flow along the wall on the source slice image of MRA. The general hemodynamics of
the phantoms on MRA were identical to hemodynamics on color Doppler imaging and CFD. The results
obtained with the phantoms matched the findings on normal volunteers.
CONCLUSION
Although representations of bifurcated carotid arterial phantoms on axial 3D-TOF MRA were
excellent if ideally desinged, the zone of reversed flow could be a significant factor in creating distorted image
when the zone of reversed flow contacted directly with curved or deformed arterial wall.