Corneal Epithelial Autograft for Limbal Dermoid

Study Overview
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Brief Summary
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The purpose of the study is to explore whether femtosecond laser-assisted corneal epithelial autograft is more effective than femtosecond laser-assisted limbal autograft for ocular surface reconstruction after excision of limbal dermoid.

Official Title
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A Non-randomized Controlled Clinical Trial of Corneal Epithelial Autograft for Limbal Dermoid

Conditions
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Corneal Dermoid

Intervention / Treatment
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* Procedure: CorneaL epithelial autograft
* Device: Femtosecond laser
* Procedure: Limbal autograft
* Device: Femtosecond laser


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age between 1 to 30 years old; Patients with limbal dermoid, scheduled for elective surgical excision; Superficial lesion ranging from 5 to 9mm, without encroaching the deep stroma layer, as indicated by anterior segment optical coherence tomography images; Informed consent signed by a parent or legal guardian, or having the capability of understanding and signing the informed consent; Being able to comply with study assessments for the full duration of the study. Exclusion Criteria: Keratoconus; Ocular and facial active inflammation such as keratitis, trachoma, dacryocystitis, blepharitis, meibomian gland dysfunction, Sjogren's syndrome, cicatricial pemphigoid etc; High myopia with a spherical equivalent of -15.0 D or less; Corneal or ocular surface infection within 30 days prior to study entry; Ocular surface malignancy; Uncontrolled diabetes with most recent Hemoglobin A1c greater than 8.5%; Renal failure with creatinine clearance< 25ml/min; Alanine aminotransferase > 40IU/L, or aspartate aminotransferase > 40IU/L; Platelet levels < 150,000 or > 450,000 per microliter; Hemoglobin < 12.0 g/dL (male) or < 11.0 g/dL (female); Prothrombin time > 16s and activated partial thrombin time > 35s in patients not accepting anticoagulant therapy; An international normalized ratio greater than 3 in patients accepting anticoagulant therapy; Pregnancy (positive test) or lactation; Participation in another simultaneous medical investigation or clinical trial; Severe cicatricial eye disease; Ocular comorbidities that affect the prognosis of transplantation, such as advanced glaucoma or retinal diseases; Severe dry eye disease as determined by Schirmer's test < 2mm at least in one eye; Any medical or social condition that in the judgement of the investigator would interfere with or serve as a contraindication to adherence to the study protocol or ability to give informed consent; Signs of current infection, including fever and treatment with antibiotics; Active immunological diseases; History of allo-limbal transplantation, penetrating keratoplasty or anti-glaucoma filtering surgeries.

Ages Eligible for Study
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Minimum Age: 1 Year
Maximum Age: 30 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Corneal epithelial autograft<br>Corneal dermoid tumor resection combined with femtosecond laser assisted corneal epithelial autograft | Procedure: CorneaL epithelial autograft<br>* After removal of the recipient's diseased dermoid, a size-match donor epithelial tissue will be obtained from the healthy area of the same eye (corneal epithelial autograft) using femtosecond laser technology, with the goal of closure of bare stromal area by sutured corneal epithelial tissue to ensure the integrity of ocular surface. This closure may also create a microenvironment that stimulates stromal cells' regenerative capacity and regulates their epithelial-mesenchymal transition process.<br>Device: Femtosecond laser<br>* A commercial femtosecond laser to create a particular shaped graft for transplantation<br>|
| Active Comparator: Limbal autograft<br>Corneal dermoid tumor resection combined with femtosecond laser assisted limbal autograft | Procedure: Limbal autograft<br>* Simple dermoid excision will be performed, followed by closure of the bare sclera by sutured femtosecond laser-assisted limbal autograft.<br>Device: Femtosecond laser<br>* A commercial femtosecond laser to create a particular shaped graft for transplantation<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Restoration of corneal surface | Restoration of a completely epithelized, stable, and avascular corneal surface. | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cosmetic improvement | A grading system from 0 to 4 with slit-lamp photographs will be used to determine cosmetic result of each graft. | 1 year | 
| Corneal Thickness | To measure corneal thickness using anterior segment optical coherence tomography. | 1 year | 
| Best corrected visual acuity | To measure best corrected visual acuity using ETDRS chart or Teller Acuity Cards. | 1 year | 
| Corneal power, astigmatism and aberration | To measure the changes of corneal power, astigmatism and aberration using autorefractor keratometer and wavefront aberrometer respectively. | 1 year | 
| Density of stromal nerve and stromal keratocytes | To assess the stromal nerve and stromal keratocytes using in vivo confocal microscopy. | 1 year | 
| Corneal haze | To assess corneal haze using in vivo confocal microscopy. | 1 year |