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A Comprehensive Assessment of Anterior Corneal Power by Different Devices

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ClinicalTrials.gov Identifier: NCT01587287
Recruitment Status : Completed
First Posted : April 30, 2012
Last Update Posted : May 1, 2012
Sponsor:
Information provided by (Responsible Party):
Yifan Feng, Wenzhou Medical College

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

Condition or disease Intervention/treatment
Myopia Device: Corneal power measurement

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.

Study Type : Observational
Actual Enrollment : 35 participants
Observational Model: Cohort
Time Perspective: Prospective
Official Title: A Comprehensive Assessment of the Precision and Agreement of Anterior Corneal Power Measurements Obtained Using Different Devices
Study Start Date : April 2011
Primary Completion Date : June 2011
Study Completion Date : July 2011

Group/Cohort Intervention/treatment
Corneal power measurement
All recruited volunteers in present study, that underwent corneal power measurement with 8 different instruments
Device: 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.
Other Name: Tomey RC-5000



Primary Outcome Measures :
  1. Flat corneal power [ Time Frame: 2 weeks ]
    The intrasession repeatability and intersession reproducibility of flat corneal curvature measurements by using the 8 commercially available instruments.

  2. Steep corneal power [ Time Frame: 2 weeks ]
    The intrasession repeatability and intersession reproducibility of Steep corneal curvature measurements by using the 8 commercially available instruments.


Secondary Outcome Measures :
  1. Vector power J0 [ Time Frame: 2 weeks ]
    The intrasession repeatability and intersession reproducibility of vector power J0 measurements by using the 8 commercially available instruments.

  2. Vector power J45 [ Time Frame: 2 weeks ]
    The intrasession repeatability and intersession reproducibility of vector power J45 measurements by using the 8 commercially available instruments.



Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years to 55 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Sampling Method:   Non-Probability Sample
Study Population

The present study's definitions of reproducibility, repeatability and agreement were based on those adopted by the British Standards Institute and the International Organization for Standardization.

Corneal curvature measurement provides crucial information for calculating intraocular lens power,screening and managing corneal refractive surgeries and corneal disease.

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, at almost the same time as the first session, by the same examiner using the same protocol.

Criteria

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.

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): NCT01587287


Locations
China, Zhejiang
Wenzhou Medical College
Wenzhou, Zhejiang, China, 325000
Sponsors and Collaborators
Wenzhou Medical University
Investigators
Principal Investigator: Yifang Feng, MD Eye Hospital, Wenzhou Medical College, China

Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: Yifan Feng, Study Director, Wenzhou Medical College
ClinicalTrials.gov Identifier: NCT01587287     History of Changes
Other Study ID Numbers: YNKT201101
First Posted: April 30, 2012    Key Record Dates
Last Update Posted: May 1, 2012
Last Verified: January 2011

Keywords provided by Yifan Feng, Wenzhou Medical College:
Anterior corneal power
Placido topographer
Scheimpflug
Precision
Agreement