Standard Versus Transepithelial Corneal Crosslinking

Nienke Soeters

Status: Completed

Conditions: Keratoconus

Treatments: Drug: Isotonic riboflavin; Drug: Ricrolin TE; Procedure: Transepithelial versus epithelium-off CXL

Study type: Interventional

Funder types: Other

Identifiers

NCT02349165

NL29961

10-374 (Registry Identifier)

Details and patient eligibility

About

The gold standard corneal crosslinking (CXL) technique involves the initial step of epithelial removal, in order to achieve a sufficient treatment effect (meaning: stabilisation of progressive keratoconus (KC). Our aim is to evaluate the effects of transepithelial CXL (TE-CXL), whereby the epithelium is left intact and the cornea is instead treated by a solution composed of 0.1% riboflavin, combined with enhancers, after which standard CXL is performed. This solution seems to facilitate riboflavin penetration into the corneal stroma through the intact epithelium. The investigators expect to achieve a similar effect of TE-CXL with the advantage of a faster healing time and less risk of infections.

Enrollment: 61 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Documented progressive KC (by Pentacam and/or corneal topography imaging).
• A clear central cornea.
• A minimal corneal thickness of ≥ 400 µm at the thinnest corneal location (Pentacam imaging).
• Minimal Snellen corrected distance visual acuity of ≥ 0.4.
• Patient age of ≥ 18 years.

For this research study, the inclusion parameters will be the same as mentioned above, with the following additional inclusion criteria:

• Documented progression of KC, as demonstrated by anterior segment imaging and/or corneal topography:

  o Defined an increase in maximal keratometry, steepest keratometry, mean keratometry or topographic cylinder value by ≥ 0.5 D over the previous 6 months and/or a decrease in thinnest pachymetry

• Documented progression of KC defined by increase in refractive cylinder of ≥ 0.5 D over the previous 6 months

Exclusion criteria

• Presence of corneal scars.
• History of epithelial healing problems.
• Presence of previous ocular infection (such as herpes keratitis).
• Patients who are pregnant and/or breastfeeding.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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61 participants in 2 patient groups

epithelium off CXL

Active Comparator group

Description:

epithelium removal + 30 minute isotonic riboflavin eye drops (3 minute interval) + 30 minutes ultraviolet-A irradiation (riboflavin every 5 minutes)

Treatment:

Procedure: Transepithelial versus epithelium-off CXL

Drug: Isotonic riboflavin

Ricrolin TE CXL

Experimental group

Description:

Ricrolin-TE eye drops for 15 minutes (2 minute interval) and 15 minute Ricrolin TE pooled on the cornea using a silicone ring + 30 minutes ultraviolet-A irradiation (Ricrolin TE every 5 minutes).

Treatment:

Drug: Ricrolin TE

Procedure: Transepithelial versus epithelium-off CXL