Corneal Collagen Crosslinking and Intacs for Keratoconus and Ectasia (CXL)

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. Identifier: NCT01112072
Recruitment Status : Active, not recruiting
First Posted : April 28, 2010
Last Update Posted : January 25, 2018
Information provided by (Responsible Party):
Cornea and Laser Eye Institute

April 26, 2010
April 28, 2010
January 25, 2018
April 2010
December 2018   (Final data collection date for primary outcome measure)
Maximum keratometry [ Time Frame: 1 year ]
Same as current
Complete list of historical versions of study NCT01112072 on Archive Site
Best Corrected Visual Acuity [ Time Frame: 1 year ]
Same as current
Not Provided
Not Provided
Corneal Collagen Crosslinking and Intacs for Keratoconus and Ectasia
Randomized Study of Safety and Effectiveness of Corneal Collagen Crosslinking and Intacs for Treatment of Keratoconus and Corneal Ectasia
This study will determine the efficacy of corneal collagen crosslinking (CXL) combined with Intacs for the treatment of keratoconus and corneal ectasia. The goal of CXL is to decrease the progression of keratoconus, while Intacs has been shown to decrease corneal steepness in keratoconus. This study will attempt to determine the relative efficacy of the two procedures either performed at the same session versus CXL performed 3 months after Intacs.
The purpose of this is to ascertain the possible additive effect of the two treatments to both improve the quality of the corneal optics (i.e. improve corneal topography regularity) and to stabilize the cornea. Previous investigations have shown that Intacs surgery, indeed, does improve corneal topography and improve contact lens tolerance and spectacle corrected visual acuity, as well as uncorrected visual acuity in some patients. Investigations of CXL have shown the procedure not only to decrease keratoconus progression, but also to decrease the steepness of the cone and improve uncorrected and best corrected visual acuity in some cases. Since the mechanism of improvement differs between the procedures, this suggests a potential additive effect of the two on the patient's ultimate visual outcome. Thus, the patient would be afforded two potential benefits: (1) the potential of a more robust visual outcome and (2) stabilization of the keratoconic cornea on the longer term.
Phase 3
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
  • Keratoconus
  • Corneal Ectasia
Drug: Riboflavin
Corneal epithelium removed followed by riboflavin drop administration every 2 minutes for 30 minutes followed by UV light exposure with additional riboflavin administration every 2 minutes for 30 minutes. Subjects will be randomized to receive Intacs placement either immediately before CXL or 3 months before CXL.
Other Names:
  • Intracorneal Ring Segments
  • Cornea Collagen Crosslinking
  • Active Comparator: Intacs combined with CXL
    Intacs placement followed by collagen crosslinking with UV light and riboflavin
    Intervention: Drug: Riboflavin
  • Active Comparator: Intacs followed by CXL
    Intacs placement, to be followed by corneal collagen crosslinking with UV light and riboflavin 3 months later
    Intervention: Drug: Riboflavin
Not Provided

*   Includes publications given by the data provider as well as publications identified by Identifier (NCT Number) in Medline.
Active, not recruiting
Same as current
December 2018
December 2018   (Final data collection date for primary outcome measure)

Inclusion Criteria:

  • 21 years of age or older
  • Having a diagnosis of keratoconus or corneal ectasia after corneal refractive surgery (e.g., LASIK, photorefractive keratectomy [PRK], or epi-LASIK)
  • Subjects who meet the manufacturer's nomogram recommendations for Intacs segments
  • Topography consistent with keratoconus or post-surgical corneal ectasia.
  • BSCVA worse than 20/20 (<55 letters on ETDRS chart)

Exclusion Criteria:

  • Eyes classified as either normal, atypical normal, or keratoconus suspect on the severity grading scheme.
  • Corneal pachymetry ≤ 400 microns at the thinnest point measured by Pentacam in the eye(s) to be treated when the isotonic riboflavin solution is used or ≤ 300 microns when the hypotonic riboflavin us used, provided that the corneal thickness after treatment with the hypotonic riboflavin solution is > 400 microns. Corneal pachymetry ≤ 450 microns at the proposed insertion site for the Intacs
  • Previous ocular condition (other than refractive error) in the eye(s) to be treated that may predispose the eye for future complications
  • History of corneal disease
  • History of chemical injury or delayed epithelial healing in the eye(s) to be treated.
  • Pregnancy (including plan to become pregnant) or lactation during the course of the study
  • A known sensitivity to study medications
  • Subjects with nystagmus or any other condition that would prevent a steady gaze during the CXL and Intacs treatment or other diagnostic tests.
  • Subjects with a current condition that, in the investigator's opinion, would interfere with or prolong epithelial healing.
Sexes Eligible for Study: All
21 Years and older   (Adult, Older Adult)
Contact information is only displayed when the study is recruiting subjects
United States
Not Provided
Not Provided
Cornea and Laser Eye Institute
Cornea and Laser Eye Institute
Not Provided
Principal Investigator: Peter Hersh, M.D. Cornea and Laser Eye Institute
Cornea and Laser Eye Institute
January 2018

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP