Clinical Applicability of pCASL as a Substitute for FDG-PET in MCI and SCD Patients

Study Overview
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Brief Summary
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The goal of this observational study is to compare cerebral perfusion patterns with pseudo-continuous arterial spin labeling (pCASL) and brain metabolism patterns with fluorodeoxyglucose-position emission tomography (FDG-PET) in patients with mild cognitive impairment (MCI) and subjective cognitive decline (SCD). The main questions it aims to answer are: Do pCASL sequences identify hypoperfusion patterns that correlate well with FDG-PET hypometabolic patterns? Are there differences in this correlation in terms of cerebrospinal fluid (CSF) profiles? Can hypoperfusion patterns in pCASL predict conversion to dementia? Participants will undergo brain 3 Tesla magnetic resonance imaging (MRI), FDG-PET, lumbal puncture and blood collection to analyze amyloid beta and tau, yearly detailed neuropsychological tests for three years.

Official Title
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Clinical Applicability of Pseudo-continuous Arterial Spin Labeling as a Substitute for FDG-position Emission Tomography in MCI and SCD Patients

Conditions
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Mild Cognitive Impairment, Subjective Cognitive Decline

Intervention / Treatment
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* Diagnostic Test: pCASL


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with mild cognitive impairment or subjective cognitive decline according to established criteria Clinical Dementia Rating scale of 0 or 0.5 Signed informed consent before study entry Exclusion Criteria: Contraindication to brain MRI, FDG-PET or lumbar puncture Secondary causes of cognitive decline Known major neurological or psychiatric comorbidities History of substance or alcohol abuse Known causes of cerebral brain perfusion alterations Enrollment in anti-amyloid or anti-tau drugs trials

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Diagnostic Test: pCASL|Brain 3 Tesla MRI with pCASL sequence|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlation between brain hypoperfusion and brain hypometabolism at baseline | The investigators will correlate cerebral perfusion indices and standardized uptake value ratios (SUVr) ratios for each pre-specified region of interest (ROI) within statistical parametric mapping (SPM) Automatic Anatomic Labeling (AAL), after coregistration on T1 sequences | Baseline | 
| Correlation between brain hypoperfusion and brain hypometabolism at baseline according to CSF profile | The investigators will correlate cerebral perfusion indices and SUVr for each pre-specified ROI (region of interest) within SPM Automatic Anatomic Labeling (AAL), after coregistration on T1 sequences. This analysis will be done within subgroups according to CSF status according to amyloid beta, phosphorylated tau and total tau. | Baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Differences among brain hypoperfusion patterns according to amyloid and tau status | The investigators will analyze differences in brain perfusion indices for each ROI among patients wit amyloid positive status, amyloid and tau negative status, and amyloid negative - tau positive status | Baseline | 
| Correlations between brain hypoperfusion and neuropsychological tests | The investigators will perform correlations between brain hypoperfusion indices for each ROI and various neuropsychological (NPS) test scores | Baseline, 1 year, 2 years | 
| Predictive properties of brain hypoperfusion and brain hypometabolism for conversion to dementia | The investigators will analyze correlations between each ROI hypoperfusion and conversion to dementia rates within the prespecified time frame. In case of significant associations, a receiver operating characteristic curve (ROC) analysis will be carried out to individuate optimal cut-offs for cerebral blood flow indices and SUVr to predict conversion of dementia | 1 year, 2 years | 
| Correlations between brain hypoperfusion and CSF and blood biomarkers | The investigators will perform correlations between brain hypoperfusion indices for each ROI and values of CSF and blood amyloid beta, phosphorylated tau and total tau | Baseline | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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pseudo-continuous arterial spin labeling, fluorodeoxyglucose positron emission tomography, mild cognitive impairment, biomarkers, subjective cognitive decline