ASL Perfusion MRI Predicts Cognitive Decline and Conversion From MCI to Dementia

Abstract

We compared the predictive value of cerebral perfusion as measured by arterial-spin labeling magnetic resonance imaging (ASL-MRI) with MRI-derived hippocampal volume for determining future cognitive and functional decline and subsequent conversion from mild cognitive impairment to dementia. Forty-eight mild cognitive impairment subjects received structural and ASL-MRI scans at baseline and clinical and neuropsychologic assessments annually. Thirteen subjects became demented during the period of longitudinal observation (2.7 ± 1.0 y). Cox regression analyses suggest that baseline hippocampal volume [relative risk (RR) = 0.99, P = 0.004], baseline right inferior parietal (RR = 0.64, P = 0.01) and right middle frontal (RR = 0.73, P = 0.01) perfusion were associated with conversion to dementia. Results from linear mixed effects modeling suggest that baseline perfusion from the right precuneus predicted subsequent declines in Clinical Dementia Rating Sum of Boxes (P = 0.002), Functional Activates Questionnaire (P = 0.01), and selective attention (ie, Stroop switching, P = 0.009) whereas baseline perfusion from the right middle frontal cortex predicted subsequent episodic memory decline (ie, total recognition discriminability score from the California Verbal Learning Test, P = 0.03). These results suggest that hypoperfusion as detected by ASL-MRI can predict subsequent clinical, functional, and cognitive decline and may be useful for identifying candidates for future Alzheimer disease treatment trials. Keywordsmild cognitive impairment; dementia; cognitive and functional decline; ASL perfusion MRI; hippocampal volume Mild cognitive impairment (MCI) is considered to be the transition between normal aging and Alzheimer disease (AD), the most prevalent dementing disorder in older adults. Studies with fluorodeoxyglucose (FDG) positron emission tomography (PET), which measures glucose metabolism, and technetium-99m hexamethylpropyleneamineoxime single photon emission NIH Public Access Author ManuscriptAlzheimer Dis Assoc Disord. Author manuscript; available in PMC 2010 May 6. Published in final edited form as:Alzheimer 7 ,8 and hippocampus, 6,9-11 are sensitive early markers of progression to AD. Using principal component analysis, Borroni et al 12 described a specific pattern of hypoperfusion in converters that involved the parietal and temporal lobes, precuneus and posterior cingulate cortex. Caroli et al 13 recently reported that compared with control subjects, amnestic MCI who converted to AD had hypoperfusion in the parahippocampal and inferior temporal cortices whereas amnestic MCI patients who did not convert to dementia had hypoperfusion in the retrosplenial cortex.To the extent that regional metabolism and perfusion are coupled, arterial spin-labeling magnetic resonance imaging (ASL-MRI), which labels arterial blood water as an endogenous diffusible tracer for perfusion, may be able to detect functional deficiencies in a way similar to FDG PET and SPECT. 14 In support of this, ASL-MRI studies of AD and...

Framingham Cardiovascular Risk Profile Correlates with Impaired Hippocampal and Cortical Vasoreactivity to Hypercapnia

“…Furthermore, both CBF reduction (Hirao et al, 2005;Caroli et al, 2007;Hansson et al, 2009;Johnson et al, 1998;Kitagawa et al, 2009;Chao et al, 2010) and deficits in the reactivity of cerebral vessels to hypercapnia (vasoreactivity to hypercapnia (VR h )) forecast cognitive decline (Silvestrini et al, 2006). It has been thus proposed that preexisting vascular risk factors mechanistically contribute to cognitive deterioration by directly compromising cerebral blood supply, especially in the states of increased demand.…”

Cerebral perfusion alterations and cerebral amyloid in autosomal dominant Alzheimer disease

“…7,[22][23][24] However, we are unaware of any existing studies in ADAD exploring CBF. The few studies using FDG-PET in ADAD have demonstrated decreased areas of metabolism, mostly in the temporal and parietal heteromodal cortices in asymptomatic to mildly symptomatic subjects.…”

Complexity across scales: a walkthrough to linking neuro-imaging readouts to molecular processes

“…Abnormal cerebral perfusion are clear indicators of diagnostic transition from MCI to AD [65,66]. Borroni and Chao et al, has demonstrated patterns of hypoperfusion in parietal, temporal and posterior cingulate cortex in all those patients who are progressing from MCI to AD [67,68]. Another study performed by Caroli et al, compared three diagnostic groups namely CN, MCI and AD.…”