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

NCT ID: NCT00838422

Last Updated: 2009-02-06

Basic Information

• Recruitment Status: UNKNOWN
• Total Enrollment: 100 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2008-06-30
• Study Completion Date: 2009-06-30

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).

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.

Conditions

Keratitis

Study Design

• Observational Model Type: COHORT
• Study Time Perspective: PROSPECTIVE

Study Groups

FD-OCT, ORA, USP

No interventions assigned to this group

Eligibility Criteria

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.

• Minimum Eligible Age: 20 Years
• Maximum Eligible Age: 70 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Far Eastern Memorial Hospital

OTHER

Sponsor Role: lead

Responsible Party

Far Eastern Memorial Hospital

Principal Investigators

Shu-Wen Chang, MD

Role: PRINCIPAL_INVESTIGATOR

Far Eastern Memorial Hospital

Locations

Far Eastern Memorial Hospital

Banqiao District, Taipei, Taiwan

Site Status: RECRUITING

Countries

Taiwan

Central Contacts

Shu-Wen Lo, MD

Role: CONTACT

swchang2007@ntu.edu.tw

02-89667000 ext. 4271

Other Identifiers

FEMH97010

Identifier Type: -

Identifier Source: org_study_id