Epithelial Thickness Map

Comparison of Two Optical Coherence Tomography Devices in Corneal Epithelial Thickness Maps

In keratoconic eyes, the corneal epithelium shows a localized thinning over the cone that is surrounded by an annulus of epithelial thickening. It has been postulated that epithelial thickness mapping can be a sensitive tool for the keratoconus diagnosis. In keratoconus screening the 5 mm diameter of the corneal centrum may be sufficient while studies have shown that the cone apex is located in this area.

Aim of this study is to assess agreement and repeatability of epithelial thickness measurements using two optical coherence tomography devices in healthy and keratoconus corneas.

Secondary objective is to evaluate the differences between healthy and keratoconus eyes using epithelial thickness map data.

This is a prospective monocentric study that includes patients divided into two groups: patients with keratoconus and a control group formed out of patients without corneal pathologies. For each patient only one eye will be included and corneal measurements will be performed, focused on the corneal epithelium thickness.

Study Overview

• Status: Unknown
• Conditions: Keratoconus
• Intervention / Treatment: Diagnostic test: Corneal epithelial thickness measurements

Detailed Description

In total 50 eyes of 50 patients will be included, divided into two groups: study group comprised of 20 eyes with diagnosed keratoconus and a control group formed out of 30 healthy eyes.

Patients included in the study will be measured with the corneal acquisition mode, also allowing for epithelium thickness data, on each device without pupil dilatation. After each measurement patients will be asked to blink in order to allow adequate tear-film recovery. Each patient will be measured three times with both devices. Only one visit will be necessary.

The order in which the measurements will be performed (Anterion or MS-39) will be randomised using randomised.org.

The corneal epithelial thickness will be measured as the distance between the air-tear and the epithelium-Bowman interfaces.

Main outcome variable:

- Mean differences in central corneal epithelial thickness between the devices investigated (+ limits of agreement (1.96xSD) between the investigated devices)

Secondary outcome variables:

• Repeatability coefficient (within subject standard deviation - SD) and coefficient of variation of the two devices
• Comparison in epithelial thickness between normal and keratoconus eyes
• Sensitivity and specificity of swept-source OCT device in keratoconus diagnosis

• Study Type: Interventional
• Enrollment (Anticipated): 50
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Oliver Findl, Prof., MD; Phone Number: +43 1 91021-84611; Email: hkh.augen.abt@wgkk.at
• Study Contact Backup: Name: Nino Hirnschall, MD, PhD; Phone Number: +43 1 91021 57564; Email: office@viros.at

Study Locations

• Austria
  • Vienna, Austria, 1140
    • Recruiting
    • Hanusch Hospital, Ophthalmology department

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 21 years to 100 years (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Patient with diagnosed keratoconus (diagnosed using tomography and topography map changes and slit-lamp changes) and patients with healthy cornea
• Age 21 and older
• Signed informed consent

Exclusion Criteria:

• Previous ocular surgery
• Associated corneal pathologies (e.g. trauma, edema, scarring)
• In women of childbearing age, a pregnancy test will be performed before inclusion into the study.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: DIAGNOSTIC
• Allocation: NON_RANDOMIZED
• Interventional Model: PARALLEL
• Masking: NONE

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
OTHER: Epithelial thickness map evaluation in keratoconus patients; Patients included in the study will be measured with the corneal acquisition mode, also allowing for epithelium thickness data, on each device without pupil dilatation Each patient will be measured three times with both devices. The corneal epithelial thickness will be measured as the distance between the air-tear and the epithelium-Bowman interfaces.	Diagnostic test: Corneal epithelial thickness measurements; Corneal epithelial thickness measurements using two optical coherence tomography devices in healthy and keratoconus corneas.
OTHER: Epithelial thickness map evaluation in healthy cornea patients; Patients included in the study will be measured with the corneal acquisition mode, also allowing for epithelium thickness data, on each device without pupil dilatation Each patient will be measured three times with both devices. The corneal epithelial thickness will be measured as the distance between the air-tear and the epithelium-Bowman interfaces.	Diagnostic test: Corneal epithelial thickness measurements; Corneal epithelial thickness measurements using two optical coherence tomography devices in healthy and keratoconus corneas.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Agreement between two ss-OCT devices in corneal epithelial thickness measurements (LoA in micrometer)	6 months

Secondary Outcome Measures

Outcome Measure	Time Frame
Repeatability between two ss-OCT devices in corneal epithelial thickness measurements (determination of within-subject standard deviation and Coefficient of variation)	6 months

Collaborators and Investigators

• Sponsor: Vienna Institute for Research in Ocular Surgery
• Investigators: Principal Investigator: Oliver Findl, Prof., MD, Head of Department of Ophthalmology, Professor, Principal Investigator

Study record dates

Study Major Dates

• Study Start (ANTICIPATED): October 15, 2020
• Primary Completion (ANTICIPATED): February 1, 2021
• Study Completion (ANTICIPATED): March 1, 2021

Study Registration Dates

• First Submitted: September 30, 2020
• First Submitted That Met QC Criteria: September 30, 2020
• First Posted (ACTUAL): October 8, 2020

Study Record Updates

• Last Update Posted (ACTUAL): October 12, 2020
• Last Update Submitted That Met QC Criteria: October 7, 2020
• Last Verified: October 1, 2020

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Eye Diseases; Corneal Diseases; Keratoconus
• Other Study ID Numbers: Epithelial thickness map

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No