Water Excitation: A Possible Pitfall in Cerebral Time-of-Flight Angiography
Elke R. Gizewskia,
Mark E. Ladda,
Andrena Paula,
Isabel Wankea,
Sophie Görickea and
Michael Forstinga
a From the Departments of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
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FIG 1. Example of an MIP reconstruction of TOF images obtained without fat saturation or water excitation, demonstrating interference from bone marrow fat. No special postprocessing was used.
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FIG 2. Setup of the flow phantom. The curved path of the tubing with flow was intended to be similar to that of intracranial vessel anatomy. The flow was adjusted to 2 mL/s (20 cm/s).
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FIG 3. MIP reconstructions of two TOF images acquired in the same subject.
A, Normal intracranial arteries acquired with a TOF sequence without water excitation.
B, Carotid artery occlusion is revealed by using a TOF sequence with water excitation.
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FIG 4. MIP reconstructions of two TOF images acquired in the flow phantom.
A, Continuous flow signal intensity acquired with a standard TOF sequence.
B, Pitfall with partially missing flow signal intensity acquired with a TOF sequence by using water excitation.
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AJNR - American Journal of Neuroradiology