Cerebral blood flow by using pulsed arterial spin-labeling in elderly subjects with white matter hyperintensities
A J Bastos-Leite1, J P A Kuijer, S A R B Rombouts
1Image Analysis Center, VU University Medical Center, Amsterdam, the Netherlands. abastosleite@med.up.pt
Background And Purpose:
On MR imaging, white matter hyperintensities (WMH) on T2-weighted images are generally considered as a surrogate marker of ischemic small vessel disease in elderly subjects. Pulsed arterial spin-labeling (PASL) is a noninvasive MR perfusion-weighted technique. We hypothesized that elderly subjects with diffuse confluent WMH should have lower cerebral blood flow (CBF) measurements than subjects with punctiform or beginning confluent WMH.
Materials And Methods:
MR images of 21 subjects (13 women; mean age, 76 years; SD, 5), stratified for the degree of WMH, from a single center within the multinational Leukoaraiosis and Disability (LADIS) study, were investigated. CBF images were obtained by means of quantitative imaging of perfusion by using a single-subtraction second version, with thin-section TI periodic saturation PASL. Values of cortical gray matter, subcortical (including white matter and deep gray matter), and global CBF were calculated. CBF measurements of subjects with diffuse confluent WMH (n = 7) were compared with those of subjects with punctiform or beginning confluent WMH (n = 14).
Results:
Subjects with diffuse confluent WMH were found to have approximately 20% lower mean global CBF (43.5 mL/100 mL/min; SD, 6.3) than subjects with punctiform or beginning confluent WMH (57.9 mL/100 mL/min; SD, 8.6; P < .01), as well as approximately 20% lower mean subcortical (P < .01) and cortical gray matter CBF (P < .05).
Conclusion:
PASL revealed a significant reduction of CBF measurements in elderly subjects with diffuse confluent WMH.
Insights
Elderly individuals with extensive white matter hyperintensities show significantly reduced cerebral blood flow (CBF). Pulsed arterial spin-labeling (PASL) MRI confirms lower CBF in those with diffuse confluent WMH, indicating impaired brain perfusion.
Area of Science:
- Neurology
- Radiology
- Medical Imaging
Background:
- White matter hyperintensities (WMH) on MRI are markers of small vessel disease in the elderly.
- Pulsed arterial spin-labeling (PASL) is a noninvasive MRI technique for measuring perfusion.
Purpose of the Study:
- To investigate the relationship between the severity of white matter hyperintensities (WMH) and cerebral blood flow (CBF) in elderly subjects.
- To determine if diffuse confluent WMH is associated with lower CBF compared to punctiform or beginning confluent WMH.
Main Methods:
- 21 elderly subjects from the LADIS study were stratified by WMH severity.
- Quantitative cerebral blood flow (CBF) images were acquired using a specific PASL technique.
- Cortical, subcortical, and global CBF values were calculated and compared between groups.
Main Results:
- Subjects with diffuse confluent WMH exhibited approximately 20% lower mean global CBF compared to those with less severe WMH (P < .01).
- Significant reductions in subcortical (P < .01) and cortical gray matter CBF (P < .05) were also observed in the diffuse confluent WMH group.
Conclusions:
- PASL MRI demonstrated a significant reduction in cerebral blood flow (CBF) in elderly individuals with diffuse confluent white matter hyperintensities.
- This finding suggests impaired brain perfusion associated with more advanced stages of small vessel disease.
