Text Size

A Comprehensive Assessment of Anterior Corneal Power by Different Devices (No)

This study has been completed.
Sponsor:
Information provided by (Responsible Party):
Yifan Feng, Wenzhou Medical College
ClinicalTrials.gov Identifier:
NCT01587287
First received: April 23, 2012
Last updated: April 28, 2012
Last verified: January 2011
History of Changes
  Purpose

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


Condition Intervention
Myopia
 Device: Corneal power measurement

Study Type: Observational
Study Design: 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

Further study details as provided by Wenzhou Medical College:

Primary Outcome Measures:
  • Flat corneal power [ Time Frame: 2 weeks ] [ Designated as safety issue: No ]
    The intrasession repeatability and intersession reproducibility of flat corneal curvature measurements by using the 8 commercially available instruments.

  • Steep corneal power [ Time Frame: 2 weeks ] [ Designated as safety issue: No ]
    The intrasession repeatability and intersession reproducibility of Steep corneal curvature measurements by using the 8 commercially available instruments.


Secondary Outcome Measures:
  • Vector power J0 [ Time Frame: 2 weeks ] [ Designated as safety issue: No ]
    The intrasession repeatability and intersession reproducibility of vector power J0 measurements by using the 8 commercially available instruments.

  • Vector power J45 [ Time Frame: 2 weeks ] [ Designated as safety issue: No ]
    The intrasession repeatability and intersession reproducibility of vector power J45 measurements by using the 8 commercially available instruments.


Enrollment: 35
Study Start Date: April 2011
Study Completion Date: July 2011
Primary Completion Date: June 2011 (Final data collection date for primary outcome measure)
Groups/Cohorts Assigned Interventions
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

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

Ages Eligible for Study:   18 Years to 55 Years
Genders Eligible for Study:   Both
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.
  Contacts and Locations
Please refer to this study by its ClinicalTrials.gov identifier: NCT01587287

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

No publications provided by Wenzhou Medical College

Additional 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
Study First Received: April 23, 2012
Last Updated: April 28, 2012
Health Authority: China: Food and Drug Administration

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

Additional relevant MeSH terms:
Myopia
Refractive Errors
Eye Diseases

ClinicalTrials.gov processed this record on May 22, 2013