MRI Study of Blood-brain Barrier Function in CADASIL

Study Overview
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Brief Summary
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Diffusion prepared pseudo-continuous ASL (DP-pCASL) is a newly proposed MRI method to noninvasively measure the function of blood-brain barrier (BBB). The investigators aim to investigate whether the water exchange rate across the BBB, estimated with DP-pCASL, is changed in patients with CADASIL, and to analyze the association between BBB water exchange rate and MRI/clinical features in these patients.

Detailed Description
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Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), caused by NOTCH3 gene mutations, is the most frequent monogenic type of hereditary cerebral small vessel disease (CSVD). The unique pathophysiological mechanisms that small vessel disorders in CADASIL are caused by genetic mutations and that the majority of patients do not combine cerebrovascular disease risk factors make CADASIL an ideal model for studying CSVD, and the imaging findings on CADASIL can be used to diagnose and investigate the etiology of CSVD. While abnormalities in the cerebrovascular structure and hemodynamics have been well demonstrated in CADASIL, the abnormality of the BBB remains controversial. One DCE-MRI study suggested an increase in BBB permeability to gadolinium contrast in CADASIL, whereas no abnormality of BBB was found in subsequent studies in mouse models and patients. The aim of this study was to assess whether BBB function is abnormal in patients with CADASIL using DP-pCASL, which is more sensitive to subtle changes in the BBB compared to DCE-MRI. The investigators hypothesized that the BBB water exchange rate (kw) is reduced in patients with CADASIL compared to controls as assessed by DP-pCASL and that the degree of reduction in BBB water exchange rate correlates with the severity of disease in patients with CADASIL.

Official Title
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MRI Study of Blood-brain Barrier Function in CADASIL

Conditions
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Cadasil, Blood Brain Barrier Defect

Intervention / Treatment
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* Other: MRI


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with CADASIL confirmed by gene or/and skin biopsy. The age range is 20-70 years old. There is no contraindication to MRI examination, and the informed consent is signed. Exclusion Criteria: Combined with definite cerebrovascular disease, or combined with brain tumor, brain trauma and other causes of brain diseases. CADASIL is not confirmed. There are contraindications to examination or refusal to sign the informed consent.

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| CADASIL patients<br>Inclusion Criteria: Patients with CADASIL confirmed by gene or/and skin biopsy. The age range is 20-70 years old. There is no contraindication to MRI examination, and the informed consent is signed. exclusion criteria： Combined with definite cerebrovascular disease, or combined with brain tumor, brain trauma and other causes of brain diseases. CADASIL is not confirmed. There are contraindications to examination or refusal to sign the informed consent. | Other: MRI<br>* All participants underwent an MR examination on a 3T whole-body Prisma MRI system (Siemens, Erlangen, Germany) with a 64-channel head coil, and a 7T whole-body MAGNETOM MR system (Siemens, Erlangen, Germany) using a 32-channel receive/birdcage transmit head coil (NOVA medical). DP-pCASL, Multi-delay pCASL (MD-pCASL) was acquired to evaluate BBB function and cerebral perfusion. T1-weighted magnetization-prepared rapid gradient echo (T1w-MPRAGE) was scanned at both 3T and 7T for registration in the post-processing workflow. T2-weighted fluid-attenuated inversion recovery (T2w-FLAIR) and T2*-weighted gradient echo (T2*w-GRE) were acquired at 7T for high-resolution structural images and evaluation of lesions.<br>* Other names: Cognitive Scale and Clinical Scale Evaluation;|
| Healthy controls<br>Inclusion Criteria: The age range is 20-70 years old. There is no contraindication to MRI examination, and the informed consent is signed. exclusion criteria： Combined with definite cerebrovascular disease, or combined with brain tumor, brain trauma and other causes of brain diseases. There are contraindications to examination or refusal to sign the informed consent. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| kw | Post-processing of DP-pCASL data was performed offline using LOFT BBB Toolbox. Head motion was corrected using SPM12 and the temporal fluctuations were minimized by using principal component analysis. DP-pCASL data with the b value of 50 s/mm2 were used to obtain the ASL signal from the tissue and capillary compartments respectively, and kw was quantified by using a single-pass approximation model with total generalized variation regularization. | 30 Minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| CBF | Post-processing of MD-pCASL data was performed offline using the BASIL toolkit of FSL. Cerebral blood flow (CBF) were calculated by a custom script using the BASIL toolkit of FSL. | 30 Minutes | 
| ATT | Post-processing of MD-pCASL data was performed offline using the BASIL toolkit of FSL. Arterial transit time (ATT) were calculated by a custom script using the BASIL toolkit of FSL. | 30 Minutes | 
| QSM | QSM image reconstruction, including phase pre-processing and estimation of susceptibility maps, followed the default QSMbox (https:// gitlab. com/ acostaj/ QSMbox) pipeline for single-echo, coil-combined data. | 30 Minutes |