the Application of Diffusion Tensor Imaging in the Evaluation of Peripheral Neuropathy in ANCA Associated Vasculitis

Study Overview
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Brief Summary
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Include qualified 50 ANCA-associated vasculitis(AAV) patients; and the first 27 patients will be divided into 3 groups with different diffused tension image (DTI) parameters and to choose the best strategy； On baseline, 6 months after treatment and 24 months after treatment, the AAV patients will accomplish the Birming-ham vasculitis activity score(BVAS) besides DTI； The new serum biomarkers of AAV associated peripheral neuropathy will be measured by ELISA； (4) Another cohort with 50 patients with AAV associated peripheral neuropathy who were evaluated by traditional methods (electromyogram) and compared to the patients cohort that evaluated using DTI by cost-benefit analysis

Official Title
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the Application of Diffusion Tensor Imaging(DTI) in the Evaluation of Peripheral Neuropathy in Anti-neutrophil Cytoplasmic Antibodies Associated Vasculitis(AAV)

Conditions
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ANCA Associated Vasculitis

Intervention / Treatment
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* Other: diffusion tensor imaging(DTI) evaluation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age between 18-80 years old； must fulfill 2012 criteria of ANCA associated vasculitis presented with peripheral neuropathy diagnosed by specialists Exclusion Criteria: the ANCA associated vasculitis is already in the stable stage after treatments any vital organ dysfunction active infection or cancer can not finish DTI scan

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

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| DTI group<br>the patient in this group will receive DTI evaluation | Other: diffusion tensor imaging(DTI) evaluation<br>* DTI is a new kind of MRI technique to evaluate peripheral neuropathy<br>|
| routine group<br>the patient in this group will receive routine evaluation | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| To assess the optimal b-value (a key parameter) for DTI in AAV associated peripheral neuropathy | b-value is a key technique parameter for DTI, which will decide the quality of DTI image | 2 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the association between normative diffusion value of DTI (FA and ADC value) and disease activity activity score of AAV (BVAS). | Birmingham Vasculitis Activity Score (BVAS) is a index of vasculitis disease activity, with the score range 0-63. Fractional anisotropy(FA) and apparent diffusion coefficient(ADC) are two parameters that can be read through DTI image . | 2 years | 
| the association between normative diffusion value of DTI (FA and ADC value) and serum biomarkers of AAV associated neuropathy | sCD163, Nfl（neurofilament light polypeptide）and OPN（osteopontin）are new biomarkers of peripheral neuropathy | 2 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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peripheral neuropathy