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

This study has been completed.
ClinicalTrials.gov Identifier:
First Posted: August 23, 2013
Last Update Posted: July 18, 2014
The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
Wenzhou Medical University
Information provided by (Responsible Party):
Yifan Feng, Wenzhou Medical University
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.

Condition Intervention
Parkinson Disease Device: Optical coherence tomography

Study Type: Observational
Study Design: Observational Model: Case Control
Time Perspective: Retrospective
Official Title: Retinal Nerve Fiber Layer Thickness Changes in Parkinson Disease: A Meta-analysis

Resource links provided by NLM:

Further study details as provided by Yifan Feng, Wenzhou Medical University:

Primary Outcome Measures:
  • Retinal Nerve Fiber Layer Thickness [ Time Frame: Baseline ]
    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.

Enrollment: 500
Study Start Date: August 2013
Study Completion Date: May 2014
Primary Completion Date: January 2014 (Final data collection date for primary outcome measure)
Groups/Cohorts Assigned Interventions
healthy control
Sex- and agematched healthy subjects
Device: Optical coherence tomography
Parkinson group
Patients with Parkinson's disease
Device: Optical coherence tomography


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Ages Eligible for Study:   18 Years to 80 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Sampling Method:   Probability Sample
Study Population
PD patients and healthy subjects were included and underwent OCT examinations

Inclusion Criteria:

  1. case-control studies;
  2. patients with PD were compared with healthy controls;
  3. all subjects underwent RNFL thickness measurement by OCT;
  4. studies should provide the data of peripapillary RNFL thickness;
  5. sample size ≥10 in each group.

Exclusion Criteria:

  1. authors did not make RNFL measurements;
  2. study without healthy control group;
  3. the outcome values can not be used for meta-analysis;
  4. duplicated articles.
  Contacts and Locations
Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01928212

China, Zhejiang
Wenzhou Medical College
Wenzhou, Zhejiang, China, 325000
Sponsors and Collaborators
Yifan Feng
Wenzhou Medical University
Principal Investigator: Yifan Feng, PhD Wenzhou Medical University
  More Information

Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: Yifan Feng, Eye Hospital, Wenzhou Medical College, China, Wenzhou Medical University
ClinicalTrials.gov Identifier: NCT01928212     History of Changes
Other Study ID Numbers: FYF20130820
First Submitted: August 20, 2013
First Posted: August 23, 2013
Last Update Posted: July 18, 2014
Last Verified: July 2014

Keywords provided by Yifan Feng, Wenzhou Medical University:
retinal nerve fiber layer thickness
optical coherence tomography
Parkinson disease

Additional relevant MeSH terms:
Parkinson Disease
Parkinsonian Disorders
Basal Ganglia Diseases
Brain Diseases
Central Nervous System Diseases
Nervous System Diseases
Movement Disorders
Neurodegenerative Diseases