Optical Coherence Tomography Angiography Examinations in Chronic Retinal Artery Occlusion

Study Overview
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Brief Summary
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Purpose of the study is to examine the retinal blood flow in chronic cases of retinal artery occlusion with non-invasive, non-contact optical coherence tomography angiography.

Detailed Description
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Occlusion of the retinal arteries is an emergency which causes sudden, painless unilateral vision loss. Loss of blood flow causes ischemic damage to the retina. The extent of damage depends on the area affected. Following the acute phase of the disease re-canalization occurs and lesser blood flow can be detected usually without functional recovery. Purpose of the study is to examine the retinal blood flow in chronic cases of retinal artery occlusion. Standard procedures to examine this disease include retinoscopy following pupil dilation, fluorescein angiography and more recently, optical coherence tomography (OCT). The latest direction in OCT development was OCT angiography (OCTA) which is a software upgrade that allows detection of blood flow based on motion contrast. Similar to previous OCT machines OCTA is also non-invasive and non-contact and does not require any intravenous agents. OCT machines are approved in the EU and the US and are not experimental devices. The device used in this study is the commercially available Zeiss Cirrus HD OCT Angioplex 5000 that operates with spectral-domain technology.

Official Title
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Optical Coherence Tomography Angiography Examinations in Chronic Retinal Artery Occlusion

Conditions
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Retinal Artery Occlusion

Intervention / Treatment
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* Device: Optical coherence tomography angiography


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: central or branch retinal artery occlusion at least 6 months of onset signed informed consent Exclusion Criteria: known epilepsy incapacity presence of optical media opacities that would disturb the imaging presence of other retinal diseases that would disturb the evaluation of images

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 99 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| CRA<br>Patients with chronic retinal artery occlusion | Device: Optical coherence tomography angiography<br>* OCTA scans per built-in device protocol<br>|
| Control<br>Healthy | Device: Optical coherence tomography angiography<br>* OCTA scans per built-in device protocol<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Capillary density in relation to healthy subjects |  | Through study completion, 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlation of capillary density and retinal thickness |  | Through study completion, 1 year |