Retinal Nerve Fiber Layer Thickness Changes in Parkinson Disease: A Meta-analysis

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 Parkinson's disease (PD),a common neurodegenerative disease characterized by motor dysfunctions, originally described by James Parkinson in 1817. PD is characterized by selective dopaminergic neuronal cells loss, 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 PD patients, we performed a meta-analysis and systematically evaluated RNFL thickness measurements with OCT in a series of PD patients and in the healthy control groups.

Official Title
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Retinal Nerve Fiber Layer Thickness Changes in Parkinson Disease: A Meta-analysis

Conditions
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Parkinson Disease

Intervention / Treatment
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* Device: Optical coherence tomography


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: case-control studies; patients with PD 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 |
| --- | --- |
| healthy control<br>Sex- and agematched healthy subjects | Device: Optical coherence tomography<br> <br> |
| Parkinson group<br>Patients with Parkinson's disease | 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, Parkinson disease