Reduced Cerebral Blood Flow in Mild Cognitive Impairment Assessed Using Phase-Contrast MRI

Abstract

There is increasing evidence of a vascular contribution to Alzheimer's disease (AD). In some cases, prior work suggests that chronic brain hypoperfusion could play a prime pathogenic role contributing to the accumulation of amyloid-β,while other studies favor the hypothesis that vascular dysfunction and amyloid pathology are independent, although synergistic, mechanisms contributing to cognitive impairment. Vascular dysfunction can be evaluated by assessing cerebral blood flow impairment. Phase contrast velocity mapping by MRI offers a non-invasive means of quantifying the total inflow of blood to the brain. This quantitative parameter could be a sensitive indicator of vascular disease at early stages of AD. In this work, phase contrast MRI was used to evaluate cerebral hemodynamics in patients with subjective memory complaints, amnestic mild cognitive impairment, and mild to moderate AD, and compare them with control subjects. Results showed that blood flow and velocity were decreased in the patients with cognitive dysfunction and the decrease correlated with the degree of cognitive impairment as assessed by means of neuropsychological tests. Total cerebral blood flow measurements were clearly reduced in AD patients, but more importantly appeared to be sensitive enough to distinguish between healthy subjects and those with mild cognitive impairment. A quantitative measurement of total brain blood flow could potentially predict vascular dysfunction and compromised brain perfusion in early stages of AD.

Effects of food supplementation on cognitive function, cerebral blood flow, and nutritional status in young children at risk of undernutrition: randomized controlled trial

“…Cerebral blood flow is also important for maintaining proper brain perfusion. Chronically low cerebral blood flow has been reported to contribute to cognitive decline and dementia in older adults,52116117118 and has been associated with autism in children 119. The increases in cerebral blood flow and oxygen metabolism in children consuming NEWSUP, especially those consuming at least 75% of their supplement, suggest changes in brain health that could be either a cause or a consequence of improved cognitive function 22120121122123124.…”

Neuroimaging advances regarding subjective cognitive decline in preclinical Alzheimer’s disease

“…To the best of our knowledge, only two studies have explored the differences in CBF between individuals with SCD and HCs. According to Hays et al, patients with SCD exhibited lower CBF in the medial orbitofrontal cortex and higher CBF in the right putamen than HCs [ 162 ], while de Eulate et al did not observe any differences in total blood flow between individuals with SCD and HCs [ 163 ].…”

“… Viviano et al, (2019) [ 115 ] 2 binary questions rs-fMRI Cross-sectional NC: n = 48 (66.96 ± 8.79) SCD: n = 35 (68.51 ± 7.66) SCD showed lower average FC. Eulate el al., (2017) [ 163 ] Memory clinic consultation ASL Cross-sectional NC: n = 32 (72.3 ± 5.6) SCD: n = 28 (67.3 ± 7.8) MCI: n = 34 (73.7 ± 7.5) AD: n = 21 (75.8 ± 6.2) No differences in CBF between SCD and HC. Hays et al, (2018) [ 162 ] Memory clinic consultation ASL Cross-sectional NC: n = 35 (73 ± 6.25) SCD: n = 35 (72.54 ± 5.07) SCD showed negative associations between verbal memory and CBF.…”

Lower cerebral blood flow in subjects with Alzheimer's dementia, mild cognitive impairment, and subjective cognitive decline using two‐dimensional phase‐contrast magnetic resonance imaging

“…A strength of our study is the relatively large sample size in each diagnostic group. An additional strength of our study is that we normalized whole-brain CBF for brain volume, a significant potential confounder in some previous studies [6] , [11] , [12] .…”

“…Furthermore, 2D PC imaging is an accurate and reproducible method to assess whole-brain CBF [10] . Two small studies and one larger study showed that 2D PC imaging is capable of measuring whole-brain CBF, which can be used to differentiate between subjects with SCD and with AD [6] , [11] , [12] . However, those studies did not adjust for brain volume.…”