The Use of MMC During PRK and Its Effect on Postoperative Topical Steroid Requirements

April 14, 2022 updated by: John Cason, United States Naval Medical Center, San Diego

The Use of Intraoperative Mitomycin-C During Photorefractive Keratectomy and Its Effect on Postoperative Topical Steroid Requirements

  1. Purpose To evaluate the use of mitomycin-C (MMC) as an intraoperative adjunct during photorefractive keratectomy (PRK), its effect on postoperative healing and its ability to reduce the postoperative topical steroid course after the surgery.
  2. Research Design This is a single-center, prospective, comparative cohort study.
  3. Hypothesis There will not be a significant difference in the refractive corrections amongst the treatment groups, 12 months after surgery.
  4. Objectives The primary study objective is to compare the effect of intraoperative MMC and a postoperative short topical steroid taper of 3 weeks, intraoperative MMC and a rapid topical steroid taper of 1 week, and a more commonly accepted postoperative regimen of a 2 month long topical steroid taper without any intraoperative MMC. The primary endpoint evaluated will be objective estimates of refractive error (WaveScan WaveFront™ System) at 12 months post-surgery. Secondarily, the extent of haze formation will be evaluated objectively using densitometry maps generated by automated Scheimpflug imaging of the cornea (Pentacam®). Furthermore, the subjective vision from the patients' perspective will be evaluated by questionnaires.

Study Overview

Status

Active, not recruiting

Conditions

Intervention / Treatment

Detailed Description

  1. Purpose To evaluate the use of mitomycin-C (MMC) as an intraoperative adjunct during photorefractive keratectomy (PRK), its effect on postoperative healing and its ability to reduce the postoperative topical steroid course after the surgery.
  2. Research Design This is a single-center, prospective, comparative cohort study.
  3. Hypothesis There will not be a significant difference in the refractive corrections amongst the treatment groups, 12 months after surgery.
  4. Objectives The primary study objective is to compare the effect of intraoperative MMC and a postoperative short topical steroid taper of 3 weeks, intraoperative MMC and a rapid topical steroid taper of 1 week, and a more commonly accepted postoperative regimen of a 2 month long topical steroid taper without any intraoperative MMC. The primary endpoint evaluated will be objective estimates of refractive error (WaveScan WaveFront™ System) at 12 months post-surgery. Secondarily, the extent of haze formation will be evaluated objectively using densitometry maps generated by automated Scheimpflug imaging of the cornea (Pentacam®). Furthermore, the subjective vision from the patients' perspective will be evaluated by questionnaire.
  5. Methodology At the Navy Refractive Surgery Center San Diego (NRSC SD), a total of 300 patients will be enrolled and randomly assigned to three cohorts. PRK will be performed in a standard fashion for all treatment groups. In the first two groups, intraoperative MMC 0.01% for a contact time of 15 seconds will be utilized. During the postoperative period, the first cohort will use the short steroid taper and the second cohort will use the rapid steroid taper. The third cohort will not receive any intraoperative MMC and will self-administer postoperative steroids, tapering for two months. All cohorts will be followed at 1 week, 1 month, 3 months, 6 months and 12 months after the procedure. Standard clinical measures of visual performance will be recorded. Since visually significant corneal haze is relatively rare, corneal densitometry will be used as an objective measure to detect subclinical corneal haze in addition to our usual subjective haze evaluation done by the clinical optometrists.

The patients will complete a voluntary questionnaire that evaluates their subjective impression of the refractive surgery, their recovery and their outcomes. Specifically, the patient will report the use of refractive correction, usefulness of the surgery at work, dry eye complaints, and subjective appraisal of their vision.

Study Type

Interventional

Enrollment (Anticipated)

300

Phase

  • Phase 2
  • Phase 3

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • California
      • San Diego, California, United States, 92134
        • Navy Warfighter Refractive Surgery Center

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

19 years to 63 years (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  1. Active duty male or female, of any race, and at least 21 years old at the time of the pre-operative examination, and have signed an informed consent. The lower age limit of 21 is intended to ensure documentation of refractive stability.
  2. Manifest spherical equivalent (MSE) from +3.00 D to -11.0D with refractive cylinder of up to 3.00 D.
  3. Best spectacle corrected visual acuity of 20/25 or better in both eyes.
  4. Stable spectacle refraction, confirmed by clinical records. Neither the spherical nor the cylindrical portion of the refraction may have changed more than 0.50 D during the six-month period immediately preceding the baseline examination for myopic patients and 0.75 for hyperopic patients.
  5. Contact lens use: Soft contact lenses must have been removed at least two (2) weeks prior to baseline measurements. Hard contact lens users (PMMA or rigid gas permeable lenses) must have removed their lenses at least four (4) weeks prior to baseline measurements.
  6. Strong motivation for attending the follow-up visits and orders to remain in the area for the duration of at least twelve months of follow up.
  7. Consent of the subject's command to participate in the study.
  8. Access to transportation to meet follow up requirements.

Exclusion Criteria:

  1. Aviators.
  2. Female subjects who are pregnant, breast-feeding, or intend to become pregnant during the course of the study.
  3. Concurrent topical or systemic medications which may impair healing, including corticosteroids, antimetabolites, isotretinoin, (Accutane™), amiodarone hydrochloride (Cordarone™), and/or sumatriptan (Imitrex™).
  4. Medical conditions which, in the judgment of the investigator, may impair healing, including but not limited to thyroid disorders and diabetes.
  5. Active ophthalmic disease, neovascularization of the cornea within 1 mm of the intended ablation zone, or lens opacity.
  6. Evidence of glaucoma or an intraocular pressure greater than 22 mm Hg at baseline.
  7. Evidence of keratoconus, corneal irregularity, or abnormal videokeratography in either eye.
  8. Patients with known sensitivity or inappropriate responsiveness to any of the medications used in the post-operative course.
  9. Any physical or mental impairment which would preclude participation in any of the examinations, such as inability to give verbal responses to eye charts.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Prevention
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Single

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Mitomycin-C; 3 week FML steroid taper
Mitomycin-C 0.01% will be administered intraoperatively during PRK for 15 seconds. The patient will take a 3 week fluorometholone 1% topical steroid taper.
Drug: Mitomycin-C
0.01% applied to cornea with a sponge during PRK
Other Names:
  • MMC
Drug: Fluorometholone 1% topical ocular steroid
topical steroid drops applied to the cornea after PRK
Other Names:
  • FML
Experimental: Mitomycin-C; 1 week FML steroid taper
Mitomycin-C 0.01% will be administered intraoperatively during PRK for 15 seconds. The patient will take a 1 week of fluorometholone 1% topical steroid.
Drug: Mitomycin-C
0.01% applied to cornea with a sponge during PRK
Other Names:
  • MMC
Drug: Fluorometholone 1% topical ocular steroid
topical steroid drops applied to the cornea after PRK
Other Names:
  • FML
Active Comparator: No mitomycin-C; 8 week FML steroid taper
No mitomycin-C will be administered during the procedure. Instead a sham application of salt solution will be given for 15 seconds. The patient will take 8 weeks of topical fluorometholone 1% topical steroid drop taper.
Drug: Fluorometholone 1% topical ocular steroid
topical steroid drops applied to the cornea after PRK
Other Names:
  • FML

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Refractive Error
Time Frame: 12 months
Objective refractive error with Wavescan Aberrometry
12 months

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Refractive Error
Time Frame: 12 months
Manifest refraction by patient subjective report
12 months
Corneal haze
Time Frame: 12 months
Subjective grading by slit lamp examiner
12 months
Corneal haze
Time Frame: 12 months
Subclinical objective measurement of corneal haze by Pentacam densitometry
12 months

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

United States Naval Medical Center, San Diego

Investigators

  • Principal Investigator: John B Cason, M.D., United States Naval Medical Center, San Diego
  • Study Director: Donna Murdoch, Ph.D., Navy Warfighter Refractive Surgery San Diego

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

August 1, 2014

Primary Completion (Anticipated)

January 1, 2023

Study Completion (Anticipated)

July 1, 2023

Study Registration Dates

First Submitted

December 20, 2013

First Submitted That Met QC Criteria

January 8, 2014

First Posted (Estimate)

January 9, 2014

Study Record Updates

Last Update Posted (Actual)

April 15, 2022

Last Update Submitted That Met QC Criteria

April 14, 2022

Last Verified

April 1, 2022

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • NMCSD.2014.0032

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Corneal Opacity

Clinical Trials on Mitomycin-C

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Papua New Guinea

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

3
Subscribe