Retinal Nerve Fiber Layer Thickness Changes in Migraine: A Meta-Analysis of Case-control Studies

Study Overview
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Brief Summary
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Optical coherence tomography (OCT) is a non-invasive retinal imaging technology that can provide high-resolution cross-sectional images of the peripapillary retinal nerve fiber layer (RNFL) and measure its thickness. A reduction of the RNFL thickness has been detected in several neurodegenerative diseases, such as multiple sclerosis, CADASIL and Alzheimer's disease. Different studies have reported RNFL changes also in migraine, is a common hereditary chronic neurovascular disorder, characterized by dysfunction of the autonomic nervous system. The pathophysiology of migraine has not been fully clarified, but there is increasing evidence that episodes of migraine with aura are initiated by a focal reduction in cerebral blood flow, which occurs most commonly in the posterior region of one hemisphere. Although vasoconstriction of cerebral and retinal blood vessels is a transient phenomenon, the chronic nature of the migraine might cause permanent structural abnormalities of the brain and also of the retina, which may correlate with RNFL thinning. Previous studies on this subject, however, reported contradicting results. Some investigations reported reductions of the RNFL thickness while others did not. In the present study, in order to determine whether RNFL thickness is reduced in migraine patients, the investigators performed a meta-analysis and systematically evaluated RNFL thickness measurements with OCT in a series of migraine patients and in the healthy control groups.

Official Title
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Retinal Nerve Fiber Layer Thickness Changes in Migraine: A Meta-Analysis of Case-control Studies

Conditions
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Migraine

Intervention / Treatment
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* Device: Device: Optical coherence tomography


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: case-control studies; patients with Migraine were compared with healthy controls; all subjects underwent RNFL thickness measurement by OCT; studies should provide the data of peripapillary RNFL thickness; sample size ≥10 in each group. Exclusion Criteria: authors did not make RNFL measurements; study without healthy control group; the outcome values can not be used for meta-analysis; duplicated articles.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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 |
| --- | --- |
| migraine group<br>Patients with migraine | Device: Device: Optical coherence tomography<br> <br> |
| healthy control<br>Sex- and agematched healthy subjects | Device: Device: Optical coherence tomography<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Retinal Nerve Fiber Layer Thickness | Retinal nerve fiber layer thickness included average thickness (360° measurement), temporal quadrant thickness (316-45°), superior quadrant thickness (46-135°), nasal quadrant thickness (136-225°) and inferior quadrant thickness (226-315°)was measured by OCT. | Baseline | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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retinal nerve fiber layer thickness, optical coherence tomography, migraine