Epi-on CuRV and Epi-off aCXL Protocols in the Management of Keratoconus

NCT ID: NCT07173907

Last Updated: 2025-09-15

Basic Information

• Recruitment Status: COMPLETED
• Total Enrollment: 135 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2016-01-01
• Study Completion Date: 2024-03-30

Brief Summary

This study investigates the effectiveness and safety of two different corneal cross-linking (CXL) protocols for the management of progressive keratoconus: the accelerated epithelium-off technique (aCXL) and the topography-guided epithelium-on Customized Remodeled Vision (CuRV) protocol. These methods differ in their mode of ultraviolet-A (UVA) energy delivery and their approach to corneal surface preservation, with potential implications for both structural stabilization and patient comfort. The primary aim was to evaluate changes in corrected distance visual acuity (CDVA) and maximum keratometry (Kmax) over a 24-month follow-up period, allowing for a direct comparison of visual and topographic outcomes between the two approaches.

By assessing these endpoints, the study seeks to address whether epithelium-on, customized cross-linking can achieve similar or improved results compared with conventional accelerated epithelium-off treatment. The findings are intended to provide insights into the relative benefits of standardized versus individualized cross-linking techniques, with the broader goal of optimizing treatment strategies for patients with keratoconus.

Conditions

Keratoconus

Study Design

• Observational Model Type: COHORT
• Study Time Perspective: PROSPECTIVE

Study Groups

CuRV CXL protocol cohort

The subjects underwent the procedure of CuRV method that was performed as an outpatient procedure under topical anesthesia (tetracaine 1%). A two-part transepithelial isotonic riboflavin system (ParaCel™ Part 1 and Part 2) was used. Part 1 was applied with a surgical spear and repeated drops, followed by Part 2 instillation for 6 minutes. After rinsing with balanced salt solution, UVA irradiation was performed using the Mosaic® device with Boost Goggles™ delivering supplemental oxygen. Pulsed UVA (365 nm, 30 mW/cm²) was applied in a personalized, three-zone pattern (15 J/cm² to the cone apex, 10 J/cm² to an intermediate annulus, and 7.2 J/cm² to the periphery), guided by Pentacam tomography. A bandage contact lens was placed at the end of the procedure.

CuRV CXL

Intervention Type: PROCEDURE

A two-part transepithelial isotonic riboflavin system (ParaCel™ Part 1 and Part 2) was used. Part 1 was applied with a surgical spear and repeated drops, followed by Part 2 instillation for 6 minutes. After rinsing with balanced salt solution, UVA irradiation was performed using the Mosaic® device with Boost Goggles™ delivering supplemental oxygen. Pulsed UVA (365 nm, 30 mW/cm²) was applied in a personalized, three-zone pattern (15 J/cm² to the cone apex, 10 J/cm² to an intermediate annulus, and 7.2 J/cm² to the periphery), guided by Pentacam tomography. A bandage contact lens was placed at the end of the procedure.

Accelerated CXL Procedure (aCXL)

The subjects underwent the aCXL procedure was performed under topical anesthesia after tailored epithelial removal, leaving a small island over the thinnest corneal area. Riboflavin-dextran solution was applied for 30 minutes, followed by UVA irradiation (9 mW/cm², total 5.4 J/cm²) using the KXL device. The cornea was rinsed with Ringer's solution during treatment, and a bandage contact lens was placed afterward.

Accelerated CXL Procedure (aCXL)

Intervention Type: PROCEDURE

The subjects underwent the aCXL procedure was performed under topical anesthesia after tailored epithelial removal, leaving a small island over the thinnest corneal area. Riboflavin-dextran solution was applied for 30 minutes, followed by UVA irradiation (9 mW/cm², total 5.4 J/cm²) using the KXL device. The cornea was rinsed with Ringer's solution during treatment, and a bandage contact lens was placed afterward.

Interventions

CuRV CXL

A two-part transepithelial isotonic riboflavin system (ParaCel™ Part 1 and Part 2) was used. Part 1 was applied with a surgical spear and repeated drops, followed by Part 2 instillation for 6 minutes. After rinsing with balanced salt solution, UVA irradiation was performed using the Mosaic® device with Boost Goggles™ delivering supplemental oxygen. Pulsed UVA (365 nm, 30 mW/cm²) was applied in a personalized, three-zone pattern (15 J/cm² to the cone apex, 10 J/cm² to an intermediate annulus, and 7.2 J/cm² to the periphery), guided by Pentacam tomography. A bandage contact lens was placed at the end of the procedure.

Intervention Type: PROCEDURE

Accelerated CXL Procedure (aCXL)

The subjects underwent the aCXL procedure was performed under topical anesthesia after tailored epithelial removal, leaving a small island over the thinnest corneal area. Riboflavin-dextran solution was applied for 30 minutes, followed by UVA irradiation (9 mW/cm², total 5.4 J/cm²) using the KXL device. The cornea was rinsed with Ringer's solution during treatment, and a bandage contact lens was placed afterward.

Intervention Type: PROCEDURE

Eligibility Criteria

Inclusion Criteria

• adult eyes
• progressive keratoconus (grades 1 to 3-4, Krumeich-Amsler classification)
• corneal thickness ≥400 μm
• endothelial cell density ≥1500 cells/mm²

Exclusion Criteria

• prior corneal surgeries
• corneal scars
• dystrophies
• marginal pellucid degeneration
• systemic connective tissue disorders
• uncontrolled diabetes
• pregnancy, or breastfeeding.

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Gemini Eye Clinic

INDUSTRY

Sponsor Role: lead

Responsible Party

Dr. Pavel Stodulka

Principal Investigator

Responsibility Role: PRINCIPAL_INVESTIGATOR

Other Identifiers

2019-18

Identifier Type: OTHER

Identifier Source: secondary_id

CXL2025

Identifier Type: -

Identifier Source: org_study_id