Pre and Post-arterial Recanalization Imaging of Central Retinal Artery Occlusions (CRAO)

Study Overview
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Brief Summary
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Central retinal artery occlusions (CRAO) are the equivalent of an ischemic stroke at the retinal level. They share the same risk factors and common pathology. The diagnosis of a CRAO is clinically based on the sudden occurrence of a decrease in deep visual acuity with fundamentally signs of reactive ischemia. Small studies have highlighted the value of cerebral MRI (Magnetic Resonance Imaging) in CRAO with almost 25% of ischemic strokes found on diffusion sequences and the demonstration of a correlation between anomalies in diffusion sequence and the probability of a pathology with a high risk of recurrence (carotid stenosis or emboligenic cardiopathy). But there are usually few radiological signs that allow a direct positive diagnosis of CRAO, an etiologic diagnosis or a prognosis. This descriptive study will focus on CRAO at the diagnostic and post-treatment phases in the short and medium term, in order to (i) identify imaging etiologic signs of CRAO with specific sequences from a 3 Tesla MRI, (ii) identify positive diagnostic signs of CRAO with the same specific sequences, (iii) correlate these signs with the visual prognosis one month after the CRAO.

Official Title
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Pre and Post-arterial Recanalization Imaging of Central Retinal Artery Occlusions (CRAO)

Conditions
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Retinal Artery Occlusion, Magnetic Resonance Imaging, Diagnosis, Etiology, Prognosis

Intervention / Treatment
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* Device: Additional MRI sequences


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 18 years of age or older CRAO (onset of symptoms ≤ 48 hours) Consent to participate in the study Exclusion Criteria: - Contraindications to 3 Tesla MRI

Ages Eligible for Study
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Minimum Age: 18 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 |
| --- |
|Device: Additional MRI sequences|Patients will be hospitalized for suspicion of CRAO. An optimized MRI will be performed with specific sequences: 3D T1 MSDE (Motion Sensitized Driven Equilibrium) dark blood; 3D Optimized diffusion centered on the optic nerves; 3D PD T1 after injection. A consultation of ophthalmology and a control MRI will be carried out one month after the CRAO. Again, specific sequences will be added: 3D T1 MSDE (Motion Sensitized Driven Equilibrium) dark blood; 3D Optimized diffusion centered on the optic nerves; DTI (Diffusion Tensor Imaging); 3D PD T1 after injection.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Contrast enhancement of the ophthalmic artery | Binary variable (yes/no) | Baseline | 
| Presence of a thrombus | Binary variable (yes/no) | Baseline | 
| Presence of an arterial stenosis of the supra aortic trunks | Binary variable (yes/no) | Baseline | 
| Hypersignal of the ophthalmic artery in diffusion | Binary variable (yes/no) | Baseline | 
| Restriction of the apparent diffusion coefficient (ADC) at the optic nerve level and at the papilla level | Binary variable (yes/no) | Baseline |