Preoperative Corneal Measurements Estimate the Corrected Distance Visual Acuity After Corneal Cross-linking

NCT06522789 | Completed

• 1 other identifier: 17-25 10.02.2017
• Study Type: interventional
• Target: 124
• Locations: 1 country
• Sites: 1

Brief Summary

This study aims to determine if objective markers describing corneal optical density (COD), thinnest corneal thickness (TCT), anterior (ARC), and posterior (PRC) surface radii over the 3mm thinnest region of the cornea could provide a model for calculating corrected distance visual acuity (CDVA) after corneal cross-linking (CXL) in keratoconus.

Conditions

Keratoconus

Keywords

Keratoconus; cross-linking; corneal optical density

Outcome Measures

Primary Outcomes (2)

• Association between preoperative corneal characteristics derived by Pentacam and subjective parameter CDVA and postoperative CDVA at the end of the follow-up period

  Associations between Corneal Optical Density, Thinnest Corneal Thickness, Anterior Radius Curvature (ARC), Posterior Radius Curvature (PRC), ARC/PRC ratio, CDVA values at the start of the study and CDVA at postoperative.

  one year

• Associations between predicted and actual CDVA following CXL

  The differences in the mean predicted values measured at six months and one year.

  one year

Secondary Outcomes (3)

• Corrected Distance Visual Acuity (CDVA) changes in all three groups during the follow up

  one year

• Corneal Optical Density (COD) changes in all three groups during the follow up

  one year

• Corneal thickness (TCT) changes in all three groups during the follow up.

  one year

Study Arms (3)

Group 1

ACTIVE COMPARATOR

The total number of patients who underwent CXL was seventy-seven; 23 were females, and 54 were males of the mean (±sd, range) age 24.2 (±7.0, 11-44) years.

Procedure: corneal cross-linking procedure

Group 2

NO INTERVENTION

Twenty-three patients, six females and 17 males of mean age 27.3 (±7.0, 17-44) years, were untreated.

Group 3

NO INTERVENTION

Twenty-four subjects, nine females and 15 males of mean age 24.7 (±7.6, 17-45) years, were recruited as controls.

Interventions

corneal cross-linking procedure PROCEDURE

Standard Dresden protocol corneal cross-linking procedure The CXL procedure adhered to the standard Dresden protocol. All patients received topical anaesthetic (Tetracaine HCL 0.5%, Alcon Forth Worth, Texas) and a miotic (Isopto Carpine 2% HCl, Alcon, Fort Worth, Texas) drops 30 minutes before the procedure. The periocular region and conjunctival sac were washed with 10% povidone-iodine (Betadine 10%, Alcaloid, Skopje). Manual epithelial scraping with a crescent knife followed. Pachymetry was kept over 400 μm during the procedure and measured with an ultrasound hand pachymeter (Pocket II, Quantel Medical, Cournon d'Auvergne, France). Riboflavin (Peschke D, Peschke Trade, Huenenberg, Switzerland) was applied every 3 minutes for 30 minutes. We performed corneal UV-A radiation with a wavelength of 370 nm and energy of 3mW using a UVA CXL lamp (VEGA CBM-X-Linker, Carleton Optical, Chesham, UK) for 30 minutes (6 cycles of 5 minutes each).

Group 1

Eligibility Criteria

• Age: 11 Years - 45 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Child (0-17), Adult (18-64)

You may qualify if:

• Group 1 consisted of cases in which the astigmatism had increased by 1D or more, according to subjective refraction and corneal surface topography, over the previous year.
• Group 2 subjects consisted of confirmed keratoconus without signs of progression who opted to continue with their prescription glasses and tear-enhancing drops where necessary
• Group 3 is a control group of age- and gender-matched individuals without signs of keratoconus.

You may not qualify if:

• prior corneal surgeries, pachymetry less than 400 microns, scars or cloudings of the cornea, chemical injuries, severe dry eye, delayed epithelial healing and any inflammatory eye surface process before the CXL procedure

Sponsors & Collaborators

• Sistina Ophthalmology Hospital: lead

Study Sites (1)

Fanka Gilevska

Skopje, 1000, North Macedonia

Location

Related Publications (1)

• Gilevska F, Biscevic A, Bohac M, Patel S. Could Automated Objective Measurements Acquired at the Preoperative Stage Estimate the Corrected Distance Visual Acuity after Corneal Cross-Linking in Keratoconus? Ophthalmol Ther. 2024 Oct;13(10):2599-2614. doi: 10.1007/s40123-024-00993-0. Epub 2024 Aug 7.

  PMID: 39110318 DERIVED

MeSH Terms

Conditions

Keratoconus

Condition Hierarchy (Ancestors)

Corneal Diseases; Eye Diseases

Study Officials

• Fanka Gilevska, PhD cand

  Sistina Ophthalmology Hospital

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal investigator

Study Record Dates

• First Submitted: July 22, 2024
• First Posted: July 26, 2024
• Study Start: April 1, 2018
• Primary Completion: July 30, 2022
• Study Completion: July 30, 2023
• Last Updated: July 30, 2024

Record last verified: 2024-07

Data Sharing

• IPD Sharing: Will not share

Locations

NO (1)