Arterial Spin Labeling MRI for Assessing Blood Perfusion in the Human Eye Repeatability Study and Clinical Application

Study Overview
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Brief Summary
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The MRI perfusion imaging using arterial spin labeling (ASL)'s non-invasive technique (i.e. without injection of contrast medium) allows, thanks to recent technological improvement of the spatial resolution, measuring several perfusion parameter of the retinal tissue such as the regional Blood Flow (rBF) or the cerebral blood flow (cBF) expressed in ml/100g/min. Reliable application of ASL thus requires the precision and specificity of the MRI protocol to be tested.

Official Title
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Arterial Spin Labeling MRI for Assessing Blood Perfusion in the Human Eye Repeatability Study and Clinical Application

Conditions
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Retinal Diseases

Intervention / Treatment
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* Diagnostic Test: MRI perfusion imaging using ASL's non-invasive technique


Participation Criteria
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Eligibility Criteria
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Carrier of target pathologies: TAO optic neuropathy, inflammatory optic neuropathy, ischemic optic neuropathy. no cardiovascular risk factors or other ophthalmological pathology adhere to the study protocol after reading the patient information document signe the informed consent form to participate in the study do not have any contraindications to an MRI examination

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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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Healthy Volunteers<br>N = 10, who do not use contact lenses or eye glasses and have a recent evaluation of vision 10/10 ta participate in the repeatability study. | Diagnostic Test: MRI perfusion imaging using ASL's non-invasive technique<br>* Patients will undergo through an MRI-scan using the ASL MRI sequence, as described per protocol.<br>|
| Experimental: Chronic<br>N = 30 (10 patients with thyroid associated orbitopathy (TAO), 10 patients with inflammatory optic neuropathy (ION), 10 patients with ischemic neuropathy), all chronic patients followed in ophthalmology consultation, enlightened volunteers ta participate in the study, and presenting a decrease in residual visual acuity entering the TAO, inflammatory or ischemic frameworks. | Diagnostic Test: MRI perfusion imaging using ASL's non-invasive technique<br>* Patients will undergo through an MRI-scan using the ASL MRI sequence, as described per protocol.<br>|
| Experimental: Acute<br>N = 30 (10 patients with TAO, 10 patients with ION, 10 patients with ischemic neuropathy) all patients seen in the acute phase in ophthalmology consultation who will accept participation in the study, knowing the constraint of repeating the examination in the chronic phase. | Diagnostic Test: MRI perfusion imaging using ASL's non-invasive technique<br>* Patients will undergo through an MRI-scan using the ASL MRI sequence, as described per protocol.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Repeatability measurement on volunteers | implementing a protocol based on 2 imaging sessions : 1st session with 2 ASL sequences and a 2nd session scheduled 5-7 days later in similar conditions including 1 ASL in volunteers will be applied. This protocol allows assessing the intra-day and the inter-day variability of the measurements using Intra-Class Correlation Coefficient and metric derived from Bland-Altman plots. A total of 20 MRI examinations are planned for this phase of the study. | 2 month | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mesurement of the retinal perfusion by MRI ASL in patient in acute phase | Analysing the retinal perfusion by ASL to be able to figure out if the decreased visual acuity has an ischemic etiology. | 4 years | 
| Mesurement of the retinal perfusion by MRI ASLin patient in a chronic phase | Following up the disease process (stability, progression or reversal of the decrease in visual acuity). | 4 years |