Working…
ClinicalTrials.gov
ClinicalTrials.gov Menu

Treatment of Keratoconus With Advanced CXL-II

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
 
ClinicalTrials.gov Identifier: NCT02514200
Recruitment Status : Unknown
Verified December 2017 by Umeå University.
Recruitment status was:  Active, not recruiting
First Posted : August 3, 2015
Last Update Posted : May 16, 2018
Sponsor:
Information provided by (Responsible Party):
Umeå University

Brief Summary:
The purpose of this study is to determine whether individualized, topography-based corneal crosslinking for keratoconus can improve the optical outcomes of the treatment.

Condition or disease Intervention/treatment Phase
Keratoconus Procedure: Topography-based CXL (KXL2) Procedure: Conventional pulsed CXL (pCXL) Drug: Riboflavin Device: Avedro KXL II Phase 2

Detailed Description:

The study is designed as a prospective, open label, randomized controlled trial involving patients aged 12 years or older of both genders with uni‐ or bilateral keratoconus planned for routine corneal crosslinking (CXL) at the Department of Clinical Sciences / Ophthalmology, Umeå University Hospital, Umeå, Sweden. The study involves 25+25 eyes with keratoconus, which are randomized to receive either conventional pulsed crosslinking with a uniform, universal 8 mm treatment pattern of 5.4 J/cm2 (pCXL; n=25), or a modified treatment ‐ individualized topography-based corneal crosslinking (KXL2; n=25). In the latter treatment zone has an individualized arcuate shape and spares a 2 mm central optical zone. The size of the treatment zone is based on Pentacam HR® corneal tomography, and is determined by the transition zone where the corneal curvature drops off by ≥2D. The energy distribution is based on the maximum corneal steepness (Kmax) value retrieved from the Pentacam HR® tomography: ≤47.0D - 7.2 J/cm2; 47.1-52.0D - 10 J/cm2; ≥52.1D - 15 J/cm2. Thus, the thin protruding areas of the cornea are crosslinked, whereas the parts with a more normal shape are not. The aim is to potentially improve the optical outcome after the treatment.

Patients are randomized to either of the two treatment arms utilizing a computer list of unique random numbers between 1 and 50; an even number will be treated with KXL2 and an uneven number with pCXL. Bilateral inclusion is allowed, and the second eye to be treated will be assigned to the other group, i.e. eye number two will not get the same treatment as eye number 1.

All patients are informed about the procedures and provide oral and written consent before inclusion in the study.

At baseline, before treatment, each eye is evaluated with autorefractometer measurement (Oculus Parc-1®), uncorrected and best spectacle‐corrected LogMAR visual acuity, Oculus Pentacam HR® Scheimpflug photography, Oculus CorVis® high-speed Scheimpflug photography, corneal endothelial photography with a specular microscope camera, Goldmann applanation tonometry and biomicroscopy.

For the Pentacam HR® rotating Scheimpflug camera, each eye is photographed using the "25 pictures" program under standardized, mesopic light conditions. Multiple variables will be analyzed, and individual photographs also will be analyzed manually for light backscatter and for the occurrence of a demarcation line, by a masked observer. The corneal biomechanical characteristics are assessed with data from the Oculus CorVis®, and corneal endothelial morphometry, including endothelial cell density is assessed manually and automatically from specular microscopy photographs taken with the Topcon SP-2000 endothelial camera. All investigations are repeated at 1 month, 3 months, 6 months and 12 months after the treatment.


Layout table for study information
Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 50 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: Treatment of Keratoconus With Advanced Corneal Crosslinking-II
Study Start Date : March 2014
Estimated Primary Completion Date : October 2019
Estimated Study Completion Date : October 2019

Resource links provided by the National Library of Medicine

Drug Information available for: Riboflavin

Arm Intervention/treatment
Experimental: Topography-based CXL (KXL2)
Individualized pulsed topography-based corneal crosslinking; 1 second on, 1 second off; 7.2J/cm2 - 15.0J/cm2; arcuate treatment zone. The Avedro KXL II™ System is used for the crosslinking after epithelial debridement in topical anesthesia and application of topical riboflavin every 3 minutes for 10 minutes.
Procedure: Topography-based CXL (KXL2)
The keratoconus cornea is treated with epithelial debridement in local anesthesia, and then soaked in Riboflavin by repeated topical application every 3 minutes during 10 minutes. The cornea is then irradiated with pulsed ultraviolet light (1s on/1s off) in a topography-based arcuate shape with the Avedro KXL2® with an energy from 7.2-15.0 J/cm2 depending on the severity of the keratoconus.

Drug: Riboflavin
Riboflavin is added topically immediately before the treatment every 3 minutes during 10 minutes in the eye to be treated

Device: Avedro KXL II
The KXL II™ System crosslinking device from Avedro, Inc. is used for ultraviolet irradiation of the cornea after riboflavin application in both treatment arms.

Active Comparator: Conventional pulsed CXL (pCXL)
Conventional pulsed corneal crosslinking; 1 second on, 1 second off; 5.4 J/cm2; 8 mm central treatment zone. The Avedro KXL II™ System is used for the crosslinking after epithelial debridement in topical anesthesia and application of topical riboflavin every 3 minutes for 10 minutes.
Procedure: Conventional pulsed CXL (pCXL)
The keratoconus cornea is treated with epithelial debridement in local anesthesia, and then soaked in Riboflavin by repeated topical application every 3 minutes during 10 minutes. The cornea is then irradiated with pulsed ultraviolet light (1s on/1s off) in a central round 8mm zone with the Avedro KXL2® with an energy of 5.4 J/cm2.

Drug: Riboflavin
Riboflavin is added topically immediately before the treatment every 3 minutes during 10 minutes in the eye to be treated

Device: Avedro KXL II
The KXL II™ System crosslinking device from Avedro, Inc. is used for ultraviolet irradiation of the cornea after riboflavin application in both treatment arms.




Primary Outcome Measures :
  1. Change from baseline in refraction [ Time Frame: 1, 3, 6 and 12 months after the treatment ]
    Change from baseline in refractive errors, including lower and higher order aberrations in the cornea.


Secondary Outcome Measures :
  1. Change from baseline in ETDRS LogMAR visual acuity [ Time Frame: 1, 3, 6 and 12 months after the treatment ]
    Changes from baseline in uncorrected and best spectacle corrected visual acuity assessed with the Early Treatment Diabetic Retinopathy Study (ETDRS) protocol, graded in logarithmic values of the minimal angle of resolution.

  2. Change from baseline in corneal densitometry [ Time Frame: 1, 3, 6 and 12 months after the treatment ]

    Change from baseline in corneal densitometry (corneal light backscatter), assessed with the Oculus Pentacam HR® rotating Scheimpflug camera.

    assessed with the Early Treatment Diabetic Retinopathy Study (ETDRS) protocol, graded in logarithmic values of the minimal angle of resolution.


  3. Change from baseline in corneal biomechanical stability measured with GAT [ Time Frame: 1, 3, 6 and 12 months after the treatment ]
    Change from baseline in biomechanical stability assessed with the Goldmann applanation tonometer (GAT).

  4. Change from baseline in corneal biomechanical stability measured with CorVis® [ Time Frame: 1, 3, 6 and 12 months after the treatment ]
    Change from baseline in biomechanical stability assessed with the Oculus CorVis high-speed Scheimpflug camera.

  5. Change from baseline in corneal endothelial morphometry [ Time Frame: 1, 3, 6 and 12 months after the treatment ]
    Change from baseline in corneal endothelial morphometry, including cell density.



Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.


Layout table for eligibility information
Ages Eligible for Study:   12 Years and older   (Child, Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  1. Patients planned for corneal crosslinking.
  2. Uni-or bilateral keratoconus diagnosis based on the Amsler‐Krumeich grading and the "Total Deviation" keratoconus quantification value from the "Belin‐Ambrosio enhanced ectasia" measurements of the Pentacam HR® Scheimpflug camera, and an altered red reflex and/or an irregular cornea seen as distortion of the keratometric mires.
  3. Progression of the keratoconus in the eye in question, documented with Scheimpflug photography using the Oculus Pentacam HR® Scheimpflug camera and/or repeated subjective refraction and keratometry.
  4. Minimum corneal thickness of 400 μm at the thinnest point after epithelial removal.
  5. ≥12 years of age
  6. No ocular abnormalities except keratoconus
  7. No previous ocular surgery
  8. No cognitive insufficiency interfering with the informed consent.

Exclusion Criteria:

  1. Age under 12
  2. Any corneal abnormalities except keratoconus
  3. Previous ocular surgery
  4. Cognitive insufficiency

Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Layout table for additonal information
Responsible Party: Umeå University
ClinicalTrials.gov Identifier: NCT02514200     History of Changes
Other Study ID Numbers: KXL2
First Posted: August 3, 2015    Key Record Dates
Last Update Posted: May 16, 2018
Last Verified: December 2017
Additional relevant MeSH terms:
Layout table for MeSH terms
Keratoconus
Corneal Diseases
Eye Diseases
Riboflavin
Anesthetics
Central Nervous System Depressants
Physiological Effects of Drugs
Vitamin B Complex
Vitamins
Micronutrients
Nutrients
Growth Substances
Photosensitizing Agents
Dermatologic Agents