Collagen Cross-linking in Keratoconus

Sponsor

Oregon Health and Science University (Other)

Overall Status

Recruiting

CT.gov ID

NCT03760432

Collaborator

National Eye Institute (NEI) (NIH)

100

Enrollment

Location

Arm

65.4

Anticipated Duration (Months)

1.5

Patients Per Site Per Month

Study Details

Study Description

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.

Condition or Disease	Intervention/Treatment	Phase
Keratoconus	Procedure: Laser Custom Corneal Collagen Cross-Linking	N/A

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.

Study Design

Study Type:

Interventional

Anticipated Enrollment :

100 participants

Allocation:

N/A

Intervention Model:

Single Group Assignment

Masking:

None (Open Label)

Primary Purpose:

Treatment

Official Title:

Clinical Trial of Laser Custom Corneal Collagen Cross-Linking in Keratoconus

Actual Study Start Date :

Jun 20, 2018

Anticipated Primary Completion Date :

Dec 1, 2023

Anticipated Study Completion Date :

Dec 1, 2023

Arms and Interventions

Arm	Intervention/Treatment
Experimental: Surgery OCT-guided custom laser CXL	Procedure: 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.

Arm

Intervention/Treatment

Experimental: Surgery

OCT-guided custom laser CXL

Procedure: 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.

Outcome Measures

Primary Outcome Measures

Improvement in best spectacle-corrected visual acuity after laser custom CXL [6 months after the CXL procedure]
The primary goal of the trial is to determine the extent of visual improvement after laser custom CXL compared to preoperative measurements. Vision will be checked at various time points, but the primary time point will be 6-months post-procedure.

Secondary Outcome Measures

Determine CXL demarcation line depth [1 month after the CXL procedure]
The study will use OCT imaging to measure the CXL demarcation line inside the entire optical zone. The demarcation line indicates the portion of corneal stroma being cross-linked. This helps determine to what extent the cornea is being strengthened.

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years and Older

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

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

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Oregon Health & Science University	Portland	Oregon	United States	97239

Sponsors and Collaborators

Oregon Health and Science University
National Eye Institute (NEI)

Investigators

Principal Investigator: David Huang, MD, PhD, Oregon Health and Science University

Study Documents (Full-Text)

None provided.

More Information

Publications

None provided.

Responsible Party:

David Huang, Peterson Professor of Ophthalmology & Professor of Biomedical Engineering, Oregon Health and Science University

ClinicalTrials.gov Identifier:

NCT03760432

Other Study ID Numbers:

6612-CXL
R01EY028755

First Posted:

Nov 30, 2018

Last Update Posted:

Mar 26, 2021

Last Verified:

Mar 1, 2021

Studies a U.S. FDA-regulated Drug Product:

Studies a U.S. FDA-regulated Device Product:

Keywords provided by David Huang, Peterson Professor of Ophthalmology & Professor of Biomedical Engineering, Oregon Health and Science University

Keratoconus (KCN)

Optical Coherence Tomography (OCT)

Collagen Cross-linking (CXL)

Additional relevant MeSH terms:

Keratoconus

Study Results

No Results Posted as of Mar 26, 2021