Temporal and Spatial Variances in Arterial Spin-Labeling Are Inversely Related to Large-Artery Blood Velocity

AJNR Am J Neuroradiol. 2017 Aug;38(8):1555-1561. doi: 10.3174/ajnr.A5257. Epub 2017 Jun 15.


Background and purpose: The relationship between extracranial large-artery characteristics and arterial spin-labeling MR imaging may influence the quality of arterial spin-labeling-CBF images for older adults with and without vascular pathology. We hypothesized that extracranial arterial blood velocity can explain between-person differences in arterial spin-labeling data systematically across clinical populations.

Materials and methods: We performed consecutive pseudocontinuous arterial spin-labeling and phase-contrast MR imaging on 82 individuals (20-88 years of age, 50% women), including healthy young adults, healthy older adults, and older adults with cerebral small vessel disease or chronic stroke infarcts. We examined associations between extracranial phase-contrast hemodynamics and intracranial arterial spin-labeling characteristics, which were defined by labeling efficiency, temporal signal-to-noise ratio, and spatial coefficient of variation.

Results: Large-artery blood velocity was inversely associated with labeling efficiency (P = .007), temporal SNR (P < .001), and spatial coefficient of variation (P = .05) of arterial spin-labeling, after accounting for age, sex, and group. Correction for labeling efficiency on an individual basis led to additional group differences in GM-CBF compared to correction using a constant labeling efficiency.

Conclusions: Between-subject arterial spin-labeling variance was partially explained by extracranial velocity but not cross-sectional area. Choosing arterial spin-labeling timing parameters with on-line knowledge of blood velocity may improve CBF quantification.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Aging / physiology
  • Anatomy, Cross-Sectional
  • Blood Flow Velocity / physiology*
  • Cerebral Arteries / diagnostic imaging*
  • Cerebral Arteries / physiology*
  • Cerebrovascular Circulation / physiology*
  • Female
  • Healthy Volunteers
  • Hemodynamics
  • Humans
  • Image Processing, Computer-Assisted
  • Magnetic Resonance Imaging
  • Male
  • Middle Aged
  • Signal-To-Noise Ratio
  • Spin Labels*
  • Stroke / diagnostic imaging
  • Stroke / physiopathology
  • White Matter / diagnostic imaging
  • Young Adult


  • Spin Labels