Corrected Measurement of the Retinal Nerve Fiber Layer Thickness by Optic Disc Configuration With the Cirrus HD OCT

Study Overview
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Brief Summary
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Because the measurement of the retinal nerve fiber layer thickness is very sensitive to the position of measurement, it may be incorrect in patients with the tilted disc. In the present study, the corrected RNFL thickness by the optic nerve head configuration using the Cirrus HD OCT will be evaluated. If the corrected RNFL thickness is more sensitive to detect the localized RNFL defect, the present software should be upgrade to reflect the optic nerve head configuration.

Detailed Description
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Finding the localized retinal nerve fiber layer (RNFL) defect and measuring the RNFL thickness are two main issues for early glaucoma detection. A recently developed imaging device, the Cirrus HD OCT, offers more detailed informations about retina architecture including optic nerve head. To calculate the RNFL thickness, the software of the Cirrus HD OCT supposes an ideal optic nerve head. However, in the cases with not ideal optic disc configuration, the measurement of the RNFL thickness is not correct. Because the measurement of the RNFL thickness is extremely sensitive to the position of measurement, patients with the tilted disc are in danger of misdiagnosis. In the present study, we want to correct the RNFL thickness measurement according to the optic nerve head configuration using the Cirrus HD OCT. If the corrected RNFL thickness is more sensitive to detect the localized RNFL defect, the present software should be upgrade to reflect the optic nerve head configuration.

Official Title
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Corrected Measurement of the Retinal Nerve Fiber Layer Thickness by Optic Disc Configuration With the Cirrus HD OCT

Conditions
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Glaucoma, Myopia

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: normal controls or glaucoma patients signal intensity of the OCT image > 8 cooperative subjects Exclusion Criteria: spherical equivalent refractive errors > +4 diopters or < -4 diopters significant media opacity previous intraocular surgery

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 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 |
| --- | --- |
| C<br>normal volunteers | |
| G<br>glaucoma patients | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the Cirrus HD OCT |  | when the OCT images are taking | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| automated visual field |  | when the OCT images are taking | 
| red-free fundus photo |  | when the OCT images are taking | 
| refractive errors |  | when the OCT images are taking | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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retinal nerve fiber layer, optic nerve head, Cirrus OCT