A Comprehensive Assessment of Anterior Corneal Power by Different Devices

Condition(s): Myopia
NCTId: NCT01587287

Official Title

A Comprehensive Assessment of the Precision and Agreement of Anterior Corneal Power Measurements Obtained Using Different Devices

Summary

To comprehensively assess the precision and agreement of anterior corneal power measurements using 8 different devices.

Detailed Description

Volunteers with healthy corneas will be measured by different instruments to detect their anterior corneal power. Only the right eye of each subject was selected. Measurements were repeated in the second session scheduled 1 to 2 weeks later.

Eligibility

Eligibility Criteria

Gender Minimum Age Maximum Age Healthy Volunteers?
Both 18 Years 55 Years True

Inclusion Criteria:

- healthy cornea,

- best corrected distance visual acuity (BCVA) equal to or better than 20/25,

- willing and able to comply with scheduled visits and other study procedures.

Exclusion Criteria:

- History of refractive surgery or any keratoplasty procedure,

- use of contact lenses,

- history of corneal dystrophies or degenerative diseases,

- history of glaucoma or ocular hypertension,

- significant subjective dry eye symptoms, Schirmer I test results of less than 5.0 mm, tear film break-up time shorter than 5 seconds and corneal fluorescein staining positive.

Interventions & Outcomes

Study Interventions & Types

Device Intervention(s)

Corneal power measurement - All subjects will be underwent a full ophthalmic examination including vision, auto- and subjective refraction, slit-lamp examination, non-contact tonometry, corneal power measurements with the 8 devices and fundus examination.

Study Outcomes

Primary Outcome(s)

Timeframe: 2 weeks
Measure: Flat corneal power
Description: The intrasession repeatability and intersession reproducibility of flat corneal curvature measurements by using the 8 commercially available instruments.
Safety Issue? No

Timeframe: 2 weeks
Measure: Steep corneal power
Description: The intrasession repeatability and intersession reproducibility of Steep corneal curvature measurements by using the 8 commercially available instruments.
Safety Issue? No

Secondary Outcome(s)

Measure: Vector power J0
Timeframe: 2 weeks
Description: The intrasession repeatability and intersession reproducibility of vector power J0 measurements by using the 8 commercially available instruments.
Safety Issue? No

Measure: Vector power J45
Timeframe: 2 weeks
Description: The intrasession repeatability and intersession reproducibility of vector power J45 measurements by using the 8 commercially available instruments.
Safety Issue? No

Facility Locations

Research Study Facility Map

Map of facility locations for this research study.

Facility is recruiting
Facility is not yet recruiting
Unknown status

Clinical Research Study Facility Locations

Wenzhou Medical College
Wenzhou, Zhejiang 325000 China

Related Keywords & Studies

Conditions and Diseases with Related Research Studies

  1. Myopia

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