Collagen Cross-linking in Keratoconus

NCT ID: NCT03760432

Last Updated: 2025-09-09

Basic Information

• Recruitment Status: RECRUITING
• Clinical Phase: NA
• Total Enrollment: 100 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2018-06-20
• Study Completion Date: 2027-12-31

Brief Summary

Optical Coherence Tomography (OCT) devices are non-contact instruments that can measure the depth of scars, other causes of cloudiness of the cornea, and degree of corneal thinning in patients with keratoconus. Laser Custom Corneal Collagen Cross-linking (CXL) significantly decreases corneal aberrations and improves vision. This study will use OCT-guided setting for the lasers used in the corneal smoothing portion of the laser custom CXL procedure to assess the affect on visual outcomes.

Detailed Description

In the U.S., CXL and topography-guided laser ablation were approved independently, but not together. Another variation in technique involves the use of mitomycin-C (MMC), which is effective in reducing corneal haze after the laser surface ablation. Use of MMC during the laser custom CXL was associated with better outcomes, but in separate trials that could not be directly compared. This study will use OCT measurements to evaluate the magnitudes of direct and indirect laser actions after the procedure.

Conditions

Keratoconus

Study Design

• Allocation Method: NA
• Intervention Model: SINGLE_GROUP
• Primary Study Purpose: TREATMENT
• Blinding Strategy: NONE

Study Groups

Surgery

OCT-guided custom laser CXL

Group Type: EXPERIMENTAL

Laser Custom Corneal Collagen Cross-Linking

Intervention Type: PROCEDURE

Preoperative measurements from the OCT are used to assist the calculation in deciding the laser depth settings for smoothing the anterior corneal surface and removing any present opacities. The surgeon uses the OCT data to plan treatment parameters while preserving at least 360 microns of residual corneal stroma using a phototherapeutic keratectomy procedure. After the laser procedure, adjunctive MMC or saline solution will be applied to the cornea in accordance with the group to which the treated eye is randomized. The CXL procedure is then performed following the FDA-approved CXL regimen by Avedro, Inc.

Interventions

Laser Custom Corneal Collagen Cross-Linking

Preoperative measurements from the OCT are used to assist the calculation in deciding the laser depth settings for smoothing the anterior corneal surface and removing any present opacities. The surgeon uses the OCT data to plan treatment parameters while preserving at least 360 microns of residual corneal stroma using a phototherapeutic keratectomy procedure. After the laser procedure, adjunctive MMC or saline solution will be applied to the cornea in accordance with the group to which the treated eye is randomized. The CXL procedure is then performed following the FDA-approved CXL regimen by Avedro, Inc.

Intervention Type: PROCEDURE

Eligibility Criteria

Inclusion Criteria

• Diagnosis of keratoconus
• Minimum corneal thickness of 410 microns

Exclusion Criteria

• Inability to maintain fixation for OCT imaging
• Inability to commit to required study visits
• Inability to give informed consent
• Eyes with concurrent retinal diseases, glaucoma, or other eye conditions that may limit the visual outcome after surgery
• Mature cataracts if found to limit visual potential to worse than 20/40

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

Sponsors

National Eye Institute (NEI)

NIH

Sponsor Role: collaborator

Oregon Health and Science University

OTHER

Sponsor Role: lead

Responsible Party

David Huang

Peterson Professor of Ophthalmology & Professor of Biomedical Engineering

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

David Huang, MD, PhD

Role: PRINCIPAL_INVESTIGATOR

Oregon Health and Science University

Locations

Oregon Health & Science University

Portland, Oregon, United States

Site Status: RECRUITING

Countries

United States

Central Contacts

Denzil Romfh, OD

Role: CONTACT

romfhd@ohsu.edu

503-494-4351

Humberto Martinez, COT

Role: CONTACT

martinhu@ohsu.edu

503-494-7712

Facility Contacts

Denzil Romfh, OD

Role: primary

romfhd@ohsu.edu

503-494-4351

Humberto Martinez, COT

Role: backup

martinhu@ohsu.edu

503-494-7712

Other Identifiers

R01EY028755

Identifier Type: NIH

Identifier Source: secondary_id

View Link

6612-CXL

Identifier Type: -

Identifier Source: org_study_id