Longitudinal Imaging in Patients With Large Vessel Vasculitis to Predict Further Disease Course

Study Overview
=================
Brief Summary
-----------------
Longitudinal imaging in patients with large vessel vasculitis to predict further disease course

Detailed Description
-----------------
This explorative longitudinal prospective observational study is to explore different aspects of vessel wall characteristics as detected by magnet resonance imaging (MRI) techniques and positron emission tomography/computer tomography (PET/CT) in patients with large vessel giant cell Arteriitis (LV-GCA) for their usefulness as predictive factor for future giant cell arteritis (GCA) relapse. It analyses parameters in PET/CT and MRI in patients with GCA at treatment stop which correlate with GCA relapse within the first 6 months after treatment stop. Patients included in the established local GCA database (BARK) will be screened for eligibility. Aortal imaging is performed during routine care according to established guidelines at diagnosis and during Follow Up at least every two years and before treatment stop.

Official Title
-----------------
Longitudinal Imaging in Patients With Large Vessel Vasculitis to Predict Further Disease Course

Conditions
-----------------
Giant Cell Arteritis, Large Vessel Giant Cell Arteriitis

Intervention / Treatment
-----------------
* Diagnostic Test: Magnet Resonance Imaging (MRI)
* Diagnostic Test: PET/CT analysis


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Confirmed diagnosis of GCA and having a diagnosis of LV-GCA confirmed by imaging (PET/CT) Informed consent to the local GCA cohort BARK Followed for GCA treatment in the outpatient department. Exclusion Criteria: Known hypersensitivity or allergy to Gadolinium (Gd)-based MRI contrast agents. Patients with cardiac pacemakers, intra cranial clips, metallic foreign bodies or other not MR-compatible implants (e.g. pumps etc.). Renal failure or severely impaired kidney function (eGFR < 30 ml/min /1,73 m2) Epilepsy.

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| patients with GCA<br>All patients presenting with a new diagnosis of LV-GCA and all patients already treated for LV-GCA and planned for treatment termination | Diagnostic Test: Magnet Resonance Imaging (MRI)<br>* MRI with and without Gadolinium contrast agent for the following vessels: thoracic aorta (ascending, arch, descending arch, left and right common carotic, subclavian, and vertebral artery)<br>Diagnostic Test: PET/CT analysis<br>* Standard value uptake measurement (SUV) based on quantitative score normalized to liver (SUV vessel max/liver mean) at the following vessel regions: Carotid artery: common, internal, external; Subclavian artery; Axillary artery; Vertebral artery; Thoracic Aorta; Abdominal Aorta; Common femoral artery; Deep femoral artery; Popliteal artery<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in mural thickening at MRI analysis | 0 = no mural thickening (maximal vessel wall thickness <2 mm for aorta, <1mm for its branches) = mural thickening (2-3 mm for aorta, 1-2 mm for its branches); = strong thickening (>3 mm for aorta, >2mm for its branches) | at time of diagnosis of GCA and before treatment stop (in order 52 weeks after treatment start) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in late mural enhancement (subjective grading) at MRI analysis | 0= no mural enhancement; slight mural enhancement; strong mural enhancement and/or perivascular enhancement | at time of diagnosis of GCA and before treatment stop (in order 52 weeks after treatment start) | 
| Change in mural edema (subjective grading) at MRI analysis | 0= no mural edema; slight mural edema; strong mural edema | at time of diagnosis of GCA and before treatment stop (in order 52 weeks after treatment start) | 
| Change in dynamic contrast agent uptake in Golden Angle Radial Sparse Parallel MRI (GRASP MRI) | Dynamic contrast agent uptake in GRASP will be assessed in areas with wall thickening (grade 1 or 2 as defined above) | at time of diagnosis of GCA and before treatment stop (in order 52 weeks after treatment start) | 
| Change in Apparent Diffusion Coefficient (ADC) as assessed with DW-MRI in absolute numbers (in mm2/s) | Apparent Diffusion Coefficient (ADC) as assessed with DW-MRI in absolute numbers (in mm2/s) | at time of diagnosis of GCA and before treatment stop (in order 52 weeks after treatment start) | 
| Change in Standard value uptake measurement (SUV) based on quantitative score normalized to liver (SUV vessel max/liver mean) at PET/CT analysis | Standard value uptake measurement (SUV) based on quantitative score normalized to liver (SUV vessel max/liver mean) | at time of diagnosis of GCA and before treatment stop (in order 52 weeks after treatment start) | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
magnet resonance imaging (MRI), Positron emission tomography/computer tomography (PET/CT), GCA relapse