Insulin Eye Drops and Epithelial Healing After Corneal Cross-linking

Cairo University24 enrolled

Overview

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.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Enrollment

Conditions

Corneal Epithelial Wound Healing Post Operative Pain

Interventions

Insulin eye dropsDRUG

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 dropsDRUG

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.

Eligibility

Sex: ALLMin age: 18 Years

Medical Language ↔ Plain English

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.

Outcomes

Primary Outcomes

Corneal epithelial wound 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.

Time frame: 7 days or until complete epithelial healing

Secondary Outcomes

Post-operative pain

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.