Time-of-Flight MR Angiography of Carotid Artery Stenosis: Does a Flow Void Represent Severe Stenosis?
Paul J. Nederkoorna,
Yolanda van der Graafa,
Bert C. Eikelboomb,
Aad van der Lugtc,
Lambertus W. Bartelsd and
Willem P.T.M. Malic
a Julius Center for Patient Oriented Research, University Medical Center Utrecht, the Netherlands
b Department of Vascular Surgery, University Medical Center Utrecht, the Netherlands
c Department of Radiology, University Medical Center Utrecht, the Netherlands
d Image Sciences Institute, University Medical Center Utrecht, the Netherlands
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FIG 1. Images in a 70-year-old man with a minor stroke of the right hemisphere.
A, MRA image shows a long flow-void artifact (arrow).
B, DSA image clearly shows a severe (70–99%) stenosis in the internal carotid artery (arrow).
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FIG 2. Images in a 64-year-old man with a TIA of the right hemisphere.
A, MRA image shows a short flow-void artifact distal to a visible irregular plaque in the internal carotid artery (arrow). All other available projections of the 3D TOF MRA images (except for two directions with over-projection that made the internal carotid artery invisible, 12 total) showed an interruption in the blood-flow signal intensity. The flow void was confirmed on the transversal 2D TOF MRA images.
B, DSA image also shows the irregular stenosis with an ulcerated plaque in the internal carotid artery. The measurement of the most severe stenosis with DSA, however, revealed a moderate (50–69%) stenosis (arrow).
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