Early Diagnosis for Ocular Ischemia Syndrome Using Arterial Spin Labeling Magnetic Resonance Imaging Technique

Study Overview
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Brief Summary
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To evaluate ocular blood perfusion status and the possibility of craniocerebral vascular lesions of patients with ocular ischemia syndrome (OIS) using arterial spin labeling (ASL) magnetic resonance imaging technique. To evaluate the specificity, sensitivity and accuracy of arterial spin labeling (ASL) magnetic resonance imaging technique in OIS diagnosis, compared with the traditional routine examination method.

Official Title
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Early Diagnosis for Ocular Ischemia Syndrome Using Arterial Spin Labeling Magnetic Resonance Imaging Technique: a Prospective Multicenter Cohort Study

Conditions
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Ocular Ischemia Syndrome

Intervention / Treatment
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* Diagnostic Test: Arterial spin labeling (ASL) magnetic resonance imaging
* Diagnostic Test: Fundus fluorescein angiography


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Ocular ischemia syndrome group: Patients diagnosed with ocular ischemia syndrome; Age-related macular degeneration group (Control group): Patients diagnosed with age-related macular degeneration; Age: 50-80 years; Sex: all; Patients signed written informed consent. Exclusion Criteria: Fundus fluorescein angiography (FFA) clear images cannot be obtained due to refractive media problems(such as corneal leukoplakia, severe cataract, vitreous hemorrhage, etc.) ; Patients with contraindications for FFA; Patients was unable to perform magnetic resonance rmaging (MRI) test; Patients with history of bleeding and cerebral infarction; Patients with a history of surgery within 3 months; Patients who had participated in other clinical trials within 3 months; Patients who disagree and refuse to participate in the trial.

Ages Eligible for Study
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Minimum Age: 50 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 |
| --- | --- |
| Ocular ischemia syndrome<br>Patients with ocular ischemia syndrome | Diagnostic Test: Arterial spin labeling (ASL) magnetic resonance imaging<br>* Arterial spin labeling (ASL) magnetic resonance imaging test<br>Diagnostic Test: Fundus fluorescein angiography<br>* Fundus fluorescein angiography test<br>|
| Control<br>Patients with age-related macular degeneration | Diagnostic Test: Arterial spin labeling (ASL) magnetic resonance imaging<br>* Arterial spin labeling (ASL) magnetic resonance imaging test<br>Diagnostic Test: Fundus fluorescein angiography<br>* Fundus fluorescein angiography test<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Blood Flow (BF) | Blood Flow (BF)：a parameter measured by arterial spin labeling perfusion MRI to qualify the perfusion in tissue-specific units (ml blood/gram tissue/time) | through study completion, an average of 2 years |