Transepithelial Corneal Collagen Cross-linking (CXL) in Treatment of Keratoconus

Phase 2

Completed

• Conditions: Keratoconus
• Interventions: Procedure: CXL without epithelial removal; Procedure: CXL with epithelial removal

• Registration Number: NCT01181219
• Lead Sponsor: University Hospital of North Norway

Brief Summary

Transepithelial CXL (performed without epithelial removal) seem to have similar clinical effect on keratoconic eyes compared to the standard CXL (which includes epithelial removal). The current study attempts to prove that hypothesis.

A prospective, controlled, randomized, contralateral trial, will involve one eye of the patient to be treated with transepithelial CXL, while the control eye will be treated with the standard CXL. Totally 20 patients (age \>18 and \<40 years) referred by an ophthalmologist to the eye department of the University Hospital North Norway for CXL treatment of bilateral progressive keratoconus, will be recruited.

Detailed Description

CXL appears to hinder the development of keratoconus by strengthening the cross-bindings in the corneal stroma with a resultant increase in corneal biomechanical strength of up to 300%. The method was introduced in the mid-nineties and has been approved for use in the EU countries since 2007. Standard treatment protocol, involving the removal of the corneal epithelium before the Riboflavin application, has been used. In order to avoid potential complications following removal of the epithelium (infection, delayed healing, scar formation, as well as discomfort and pain), a modified procedure where the epithelium is kept intact, so called transepithelial CXL, has been suggested. According to the preliminary results of the published retrospective studies, no significant difference in the clinical effect between the standard CXL with epithelial removal and the transepithelial CXL was found.

Study Timeline

• Study Start: 2010-07
• Study First Submitted: 2010-08-12
• Study First Submitted QC: 2010-08-12
• Study First Posted: 2010-08-13
• Status Verified: 2012-05
• Primary Completion: 2014-12
• Study Completion: 2014-12
• Last Update Submitted: 2014-12-11
• Last Update Posted: 2014-12-12

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 20

Inclusion Criteria

• Documented keratoconus progression in both eyes during the last 12 months before the treatment - decrease in best spectacle-corrected visual acuity (BSCVA) and/or increase in cornea curvature or asymmetry
• Corneal thickness ≥400μm at the thinnest point
• Age range from 18 to 40
• Amsler-Krumeich classification graded stage I to III

Exclusion Criteria

• Corneal thickness <400μm at the thinnest point
• History of viral keratitis
• Severe dry eye
• Concurrent corneal infections
• Previous ocular surgery
• Hard contact lens wear for ≤4 weeks before baseline examination

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
CXL without epithelial removal	CXL without epithelial removal	Application of Riboflavin and the consequent UV-irradiation with intact corneal epithelium
CXL with epithelial removal	CXL with epithelial removal	Corneal epithelial removal prior to Riboflavin and the consequent UV-irradiation

Primary Outcome Measures

Name	Time	Method
Best corrected distant visual acuity (BCDVA)	One year

Secondary Outcome Measures

Name	Time	Method
Corneal topographic keratoconus features	One year	Corneal topographic features (and indices) showing keratectatic development will be followed (K-values, optical asymmetry, posterior surface protrusion and thickness).

Trial Locations

Locations (1)

University Hospital North Norway; 🇳🇴 Tromsoe, Troms, Norway