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

Keratitis Clinical Trial

Official title:

Repeatability and Reproducibility of Pachymetric Mapping With Fourier Domain Optical Coherence Tomography, Ocular Response Analyzer, Confoscan 4 and Ultrasound

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT00838422
• Other study ID #: FEMH97010
• Status: Recruiting
• Phase: N/A
• First received: February 4, 2009
• Last updated: February 5, 2009
• Start date: June 2008
• Est. completion date: June 2009

Study information

• Verified date: February 2009
• Source: Far Eastern Memorial Hospital
• Contact: Shu-Wen Lo, MD
• Phone: 02-89667000
• Email: swchang2007[@]ntu.edu.tw
• Is FDA regulated: No
• Health authority: Taiwan: Institutional Review Board
• Study type: Observational

Clinical Trial 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).

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.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 100
• Est. completion date: June 2009
• Est. primary completion date: January 2009
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Both
• Age group: 20 Years to 70 Years

Eligibility

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.

Study Design

Observational Model: Cohort, Time Perspective: Prospective

Related Conditions & MeSH terms

• Keratitis

Locations

Country	Name	City	State
Taiwan	Far Eastern Memorial Hospital	Pan-Chiao	Taipei County

Sponsors (1)

Lead Sponsor	Collaborator
Far Eastern Memorial Hospital

Country where clinical trial is conducted

Taiwan, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Repeatability and reproducibility of corneal thickness measurement		3 months	No
Secondary	Comparing central corneal thickness measurement among FD-OCT, ORA, and USP		3 months	No