Cerebral blood flow alterations measured by ASL-MRI as a predictor of vascular dementia in small vessel ischemic disease.

BACKGROUND

Cerebral small vessel ischemic disease (SVID) as a common age-related morbidity is the key mechanism of vascular cognitive impairment (VCI). This study uses Cerebral blood flow (CBF) measured by pseudo-continuous ASL MRI in SVID patients with and without cognitive impairment to differentiate VCI from normal aging.

MATERIALS AND METHODS

In this cross-sectional study, 74 SVID patients, including 35 with diagnosed VCI and 39 without cognitive impairment (control) underwent pCASL-MRI in the resting state. ROI-based approach pre-processing, denoising techniques, and correction for partial volume effects were performed. Regional CBF was compared between severe cognitive impairment (SCI), mild cognitive impairment (MCI), and SVID patients without cognitive impairment.

RESULTS

Total and regional CBF values in the thalamus, left cortex, hippocampus, post cingulate cortex, precuneus, insula, putamen, and middle temporal lobe was lower in VCI compared to SVID, also in SCI compared MCI group. There was a linear correlation between the Mini-Mental State Examination (MMSE) z score and CBF in the thalamus region in SVID participants and between the MMSE z score and CBF in the medial temporal region in MCI participants. The medial temporal atrophy )MTA( z score was significantly correlated with CBF values in the hippocampus and medial temporal regions in SCI and MCI also a significant correlation was seen between total CBF and Fazekas score.

CONCLUSION

Due to the growing prevalence of dementia and the role of CBF as a predictive biomarker, ASL-MRI as a non-invasive method can be easily added to diagnostic tools of cognitive impairment in individuals with SVID to recognize the initiation of vascular cognitive impairment.