Skip to main content
OpenTrials
Completed

NCT Number: NCT07812129

Insulin Eye Drops and Epithelial Healing After Corneal Cross-linking

The goal of this clinical trial was to learn if topical insulin eye drops affected corneal epithelial wound healing after corneal collagen cross-linking. The main questions it aimed to answer were:

Does topical insulin accelerate corneal epithelial healing after corneal collagen cross-linking? Does it affect post-operative pain?

Participants were all diagnosed as having bilateral progressive Keratoconus and were already scheduled for bilateral cross-linking:

Post-operatively, they were asked to apply insulin eye drops in one eye only (4 times daily) in addition to the prescribed routine post-operative treatment which was applied to both eyes.

They were also asked to come for follow-up visits on post-operative day 1,2,3,5 and 7 or until complete corneal wound healing.

The epithelial defect was measured in each eye and the participants were asked to report the degree of pain they felt in each eye at each visit until complete epithelial healing.

Completed

Looking for future studies?

Notify Me

Key information

Conditions

Corneal Epithelial Wound Healing Corneal Diseases Eye Diseases Neurologic Manifestations Pain Pain, Postoperative Pathologic Processes Pathological Conditions, Signs and Symptoms Post Operative Pain Postoperative Complications Signs and Symptoms

Age range

18 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 2 / Phase 3

Primary location

Cairo University Faculty of Medicine (Kasr Al Ainy)

Cairo, Al-Manial, 11956, Egypt

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Patients above 18 years old diagnosed with bilateral progressive Keratoconus with central corneal thickness more than 400 microns at thinnest location.

Exclusion criteria

  • Patients with signs of infectious keratitis (bacterial, fungal, protozoal or mixed poly-microbial).
  • Patients with a history of herpetic keratitis or having diminished corneal sensation.
  • Patients with severe dry eye, apical corneal scarring, hydrops, a history of corneal surgery, or ophthalmic disease other than keratoconus.
  • Single eyed patients.
  • Patients on systemic treatment involving steroids or immune-compromised patients.
  • Patients who cannot be monitored with frequent visits as required in the study protocol.
  • Pregnant and nursing females.

Treatment and study plan

insulin eye drops

Drug

A paired-eye interventional study exploring the effect of insulin eye drops on corneal epithelial wound healing after corneal collagen cross-linking in Keratoconus patients. Each patient served as their own control, where on eye received insulin eye drops post-operatively while the fellow eye (control) didn't.

standard post-operative topical drops

Drug

The standard post-operative treatment prescribed to both eyes included Moxifloxacin 0.5% (Fortymox; Orchidia, Egypt), Tobramycin 0.3% + Dexamethasone 0.1% (Tobradex; Novartis, Switzerland), and a sodium hyaluronate/hydroxypropyl guar tear substitute (Systane Hydration; Alcon, USA), each four times daily.

Primary outcomes

  1. Corneal epithelial wound healing

    Time frame: 7 days or until complete epithelial healing

    Patients were examined on post-operative days 1, 2, 3, 5, and 7, or until complete epithelization in both eyes. During these visits, the bandage contact lens were removed and the size of the epithelial defect was measured (guided by fluorescein staining) at its greatest dimension, along two perpendicular axes with a slit lamp micrometer. The healing rate, which is the speed at which the corneal epithelium heals, was assessed. It involved measuring the epithelial defect size changes over time by calculating the percentage of epithelial defect closure: (Original epithelial defect area - Current epithelial defect area)/(Current epithelial defect area) x 100. The percentage was calculated at each visit by the same examiner.

    New bandage contact lenses were applied after each examination until complete epithelial healing was achieved.

Secondary outcomes

  1. Post-operative pain

    Time frame: 7 days or until complete epithelial healing

    At each visit, assessment of patient comfort was evaluated for each eye separately by using the Verbal Rating Scale (VRS), which consists of a series of words commonly used to describe pain (0: no pain, 1: mild pain, 2: moderate pain, 3: severe pain, 4: very severe pain, 5: the worst pain ever), the patient was asked to describe the pain in each eye using these words.

Sponsors and collaborators

Lead sponsor

Cairo University

Other

Registry information

Official study title

The Effect of Topical Insulin Eye Drops On Corneal Epithelial Wound Healing After Corneal Collagen Cross-linking in Keratoconus Management: A Paired-Eye Study

Important dates

Study start
2023
Primary completion
2025
Study completion
2025
First posted
Sep 10, 2026
Registry last updated
Sep 10, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.