Reliability of Pachymetry Measurement With FD-oCT, ORA, Confoscan 4 and Ultrasound

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. Identifier: NCT00838422
Recruitment Status : Unknown
Verified February 2009 by Far Eastern Memorial Hospital.
Recruitment status was:  Recruiting
First Posted : February 6, 2009
Last Update Posted : February 6, 2009
Information provided by:
Far Eastern Memorial Hospital

Brief Summary:
The purpose of this study is to assess the repeatability, reproducibility, and agreement of central corneal thickness measured by Fourier Domain Optical Coherence tomography (FD-OCT, OptoVue, USA) with anterior corneal module, 20MHz ultrasound pachymetry equipped with Ocular response analyzer (ORA, Reichert Ophthalmic Instruments, USA) and 10MHz Ultrasound Pachymetry (USP).

Condition or disease

Detailed Description:
Corneal thickness measurements are clinically important. Variation in corneal thickness affects the accuracy of applanation tonometry. A meta-analysis by Doughty and Zaman showed that a 10% change in central corneal thickness may result in an approximately 3.4-mmHg change in intraocular pressure.1 Accuracy of corneal thickness measurement is also important in considering eligibility for refractive surgery, and the amount of correction that can safely be performed. Underestimation of corneal thickness may lead to eligible patients being excluded for primary or enhancement refractive procedures. Overestimation may lead to over-ablation and inadvertent thinning of the stroma, thereby increasing the risk of iatrogenic keratectasia. Hence, studies assessing corneal thickness measurements by various instruments are of high clinical relevance.2-9 Fourier domain optical coherence tomography (FD-OCT, OptoVue, U.S.A), Confoscan 4 (CS-4, Nidek, USA) and ocular response analyzer (ORA, Reichert, USA) are non-invasive medical devices that have recently received FDA approval for measurement of the cornea thickness. However, the repeatability and reproducibility of these instruments remains unproven in the clinical settings. To our knowledge, this is the first study to describe agreement, repeatability and reproducibility in corneal pachymetric mapping between FD-OCT, ORA, CS-4 and conventional ultrasound (US), which has been the current reference corneal pachymetric mapping system for the majority of refractive surgeons.

Study Type : Observational
Estimated Enrollment : 100 participants
Observational Model: Cohort
Time Perspective: Prospective
Official Title: Repeatability and Reproducibility of Pachymetric Mapping With Fourier Domain Optical Coherence Tomography, Ocular Response Analyzer, Confoscan 4 and Ultrasound
Study Start Date : June 2008
Estimated Primary Completion Date : January 2009
Estimated Study Completion Date : June 2009

Resource links provided by the National Library of Medicine


Primary Outcome Measures :
  1. Repeatability and reproducibility of corneal thickness measurement [ Time Frame: 3 months ]

Secondary Outcome Measures :
  1. Comparing central corneal thickness measurement among FD-OCT, ORA, and USP [ Time Frame: 3 months ]

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Ages Eligible for Study:   20 Years to 70 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Sampling Method:   Non-Probability Sample
Study Population
Healthy volunteer who has no prior ocular disease history and prior intraocular surgical history

Inclusion Criteria:

  • Healthy Volunteers

Exclusion Criteria:

  • Patients who had history of prior ocular surgery, ocular abnormalities other than cataract or refractive error or were unable to cooperate in the examination were excluded.

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 identifier (NCT number): NCT00838422

Contact: Shu-Wen Lo, MD 02-89667000 ext 4271

Far Eastern Memorial Hospital Recruiting
Pan-Chiao, Taipei County, Taiwan, 220
Principal Investigator: Shu-Wen Chang, MD         
Sponsors and Collaborators
Far Eastern Memorial Hospital
Principal Investigator: Shu-Wen Chang, MD Far Eastern Memorial Hospital

Responsible Party: Shu-Wen Chang, Far Eastern Memorial Hospital Identifier: NCT00838422     History of Changes
Other Study ID Numbers: FEMH97010
First Posted: February 6, 2009    Key Record Dates
Last Update Posted: February 6, 2009
Last Verified: February 2009

Additional relevant MeSH terms:
Corneal Diseases
Eye Diseases