Higher Irradiance in Keratoconus Ectasia

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. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details. Identifier: NCT01789333
Recruitment Status : Recruiting
First Posted : February 12, 2013
Last Update Posted : September 29, 2017
Information provided by (Responsible Party):
Stephen Trokel, Columbia University

Brief Summary:
The purpose of the study is to see if brighter lights will allow for shortening of the treatment time required to stabilize the eyes of patients with keratoconus or a bulging cornea. The investigators will be comparing the therapeutic effects of two different higher brightnesses of ultra violet light on a riboflavin treated eye. One light will be twice as bright as the other and the exposure time of these brighter lights to deliver equivalent energy to the cornea will be reduced from the standard 30 minutes to 10 and 5 minutes. Riboflavin is vitamin B2 and the investigators are trying to determine if an identical clinical effect can be achieved the brighter treatment lights are used for shorter times. The investigators will also monitor the clinical effect and the status of the cornea to see if additional risks are associated with the brighter light.

Condition or disease Intervention/treatment Phase
Keratoconus Ectasia Device: UVA Light with irradiance exposure of 9 mW/cm2 Drug: Riboflavin 0.1% ophthalmic solution Not Applicable

Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 30 participants
Intervention Model: Single Group Assignment
Intervention Model Description: 30 patients will be treated at 9 mw/cm2.
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: Study of the Safety and Effectiveness of Photochemically Induced Collagen Cross- Linking at Higher Irradiances in Patients With Keratoconus or Ectasia
Study Start Date : August 2010
Estimated Primary Completion Date : December 30, 2018
Estimated Study Completion Date : December 30, 2018

Resource links provided by the National Library of Medicine

Drug Information available for: Riboflavin

Arm Intervention/treatment
Experimental: 9 mw/cm2 at 10 minutes group
30 patients will be treated with UVA light source at 9 mw/cm2 at 10 minutes. Drug: Riboflavin Dose:1 drop every 2 to 3 minutes for 15 to 20 minutes
Device: UVA Light with irradiance exposure of 9 mW/cm2

The device's light emitting diode (LED) is used to deliver a metered dose of UV-A light to a targeted treatment area for illuminating the cornea during corneal collagen cross-linking.

The aperture setting will be set at 10 mm, and the eye will be irradiated for 10 minutes for the high irradiance exposure of 9 mW/cm2. During the exposure, instillation of riboflavin will continue (1 drop every 3 minutes).

Drug: Riboflavin 0.1% ophthalmic solution

The speculum is removed and one (1) drop of Riboflavin 0.1% ophthalmic solution will be instilled topically in the eye every 3 minutes for 30 minutes. At the end of the 30 minute riboflavin pre-treatment period, the eye will be examined to assure the presence of a yellow flare in the anterior chamber, indicating riboflavin saturation of the corneal tissue. If the yellow flare is not detected, riboflavin will continue to be instilled until the presence of the yellow flare in the anterior chamber is confirmed.

During UVA irradiation, instillation of riboflavin will be continued every 3 minutes. For a 30-minute pre-treatment and 30-minute irradiation, the total dose of riboflavin solution is approximately 32 drops, or 1.6 ml (1 drop = 0.05 ml; 1.6 mL = 1.6 mg riboflavin).

Other Name: Riboflavin

Primary Outcome Measures :
  1. Change in Total Optical Aberrations of the Cornea following Cross-Linking [ Time Frame: Baseline to 6 months ]
    Assessment of changes in corneal curvature, as analyzed using a Pentacam Scheimpflug Analyzer will be used in all patients. This allows measurement of corneal thickness, maximum and minimum curvatures and aberration analysis of the cornea as an optical element. The most significant objective measure of change is the total Higher Order Aberrations of the cornea and the Kmax, or steepest curvature of the cornea. Analysis of corneal curvature is directly related to improvement in the corneal shape which is directly related to visual function.

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.

Ages Eligible for Study:   16 Years and older   (Child, Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

Subjects who have one or both eyes that meet two of the following criteria will be considered candidates for this study:

  1. 16 years of age or older
  2. Having a diagnosis of progressive keratoconus or pellucid marginal degeneration.

    1. Characteristic pattern of deformity as analyzed by the Pentacam map.
    2. Minimal thickness of 350 microns
  3. The ability to sign a written informed consent
  4. States a willingness and ability to comply with schedule for follow-up visits
  5. Subject willing to remove contact lenses prior to evaluation and treatment

Inclusion criteria for ectasia

  1. History of having undergone a keratorefractive procedure and show:

    1. Steepening by Pentacam study
    2. Thinning of cornea
    3. Shift in the position of thinnest portion of cornea
    4. Unstable refraction with increasing myopia and astigmatism
    5. Development of irregular astigmatism
  2. At least two of the above criteria must be present.

Exclusion Criteria:

Subjects meeting any of the following criteria will be excluded from this study:

Subjects meeting any of the following criteria will be excluded from this protocol:

  1. Eyes classified as either normal or atypical normal,
  2. Corneal pachymetry ≤ 350 microns at the thinnest point in treatment zone measured by Pentacam.
  3. A history of delayed epithelial healing.
  4. Pregnancy (including plan to become pregnant) or lactation during the course of the study
  5. A known sensitivity to study medications
  6. Patients with nystagmus or any other condition that is severe enough to prevent steady gaze during the treatment
  7. Inability to cooperate with diagnostic tests.
  8. Patients with a current condition that, in the investigator's opinion, would interfere with or prolong epithelial healing.
  9. Patients who are unable to remain supine and tolerate a lid speculum.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT01789333

Contact: MaEdylin Bautista 212-305-5922

United States, New York
Edward Harkness Eye Institute-Columbia University Medical Center Recruiting
New York, New York, United States, 10032
Contact: MaEdylin Bautista    212-305-5922   
Principal Investigator: Stephen Trokel, MD         
Sponsors and Collaborators
Stephen Trokel
Principal Investigator: Stephen Trokel, MD Columbia University

Responsible Party: Stephen Trokel, Professor of Clinical Ophthalmology, Columbia University Identifier: NCT01789333     History of Changes
Other Study ID Numbers: AAAF4157
First Posted: February 12, 2013    Key Record Dates
Last Update Posted: September 29, 2017
Last Verified: September 2017
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: Undecided

Keywords provided by Stephen Trokel, Columbia University:
UVA light
irregular astigmatism

Additional relevant MeSH terms:
Dilatation, Pathologic
Corneal Diseases
Eye Diseases
Pathological Conditions, Anatomical
Ophthalmic Solutions
Pharmaceutical Solutions
Vitamin B Complex
Growth Substances
Physiological Effects of Drugs
Photosensitizing Agents
Dermatologic Agents