Accurate, localized quantification of white matter perfusion with single-voxel ASL.
Quantification of perfusion in white matter is still difficult due to its low level, causing an often insufficiently low signal-to-noise ratio, and its long and inhomogeneous transit delays. Here, a technique is presented that accurately measures white matter perfusion by combining a spectroscopic single-voxel localization technique (point-resolved spectroscopy) with a pulsed arterial spin labeling encoding scheme (flow-sensitive alternating inversion recovery) to specifically address the properties of white matter. The transit delay was measured by shifting the position of a slice-selective saturation pulse between inversion and acquisition. Perfusion measurements resulted in values of 15.6 ± 3.2 mL/100 g/min in the left and 15.2 ± 4.8 mL/100 g/min in the right hemispheric white matter and 83.2 ± 15.2 mL/100 g/min in cortical gray matter. Taking dispersion of the transit times into account does not cause a significant change in the measured values.
Magnetic Resonance Center, Max Planck Institute for Biological Cybernetics, Tübingen, Germany. rolf.pohmann@tuebingen.mpg.de
Rolf
R
Pohmann
D000465:Algorithms; D001783:Blood Flow Velocity / Q000502:physiology; D001921:Brain / Q000098:blood supply / Q000166:cytology / Q000502:physiology*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D009413:Nerve Fibers, Myelinated / Q000502:physiology* / Q000648:ultrastructure; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity