Corneal Epithelial Autograft With Middle Lamellar Keratoplasty for Severe Ocular Burns

A Clinical Trial of Corneal Epithelial Autograft Combined With Allogeneic Middle Lamellar Keratoplasty for Patients With Severe Ocular Burns

The purpose of this pilot study is to explore whether corneal epithelial autograft (EA) combined with allogeneic middle lamellar keratoplasty (AMLK) is more effective than limbal autograft (LA) with AMLK for ocular surface reconstruction in patients with severe ocular burns.

Inclusion Criteria:

1. Unilateral severe ocular burns with more than half limbal stem cells deficiency (LSCD). The history of the disease is at least 12 months at the time of screening visit.
2. Presence of superficial neo-vascularization affecting at least 2 cornea quadrants and involving central cornea.
3. Informed consent signed by a patient or legal guardian, or having the ability to comply with study assessments for the full duration of the study.

Exclusion Criteria:

1. LSCD of mild degree, with less than 2 quadrants of neo-vessel invasion and without central cornea involvement.
2. LSCD by ocular surface disorders other than ocular burns.
3. Eyelids malposition.
4. The center corneal thickness<450µm, the depth of corneal opacity<150µm or the full corneal lamellar opacity.
5. High myopia with a spherical equivalent of -15.0 D or less.
6. Corneal or ocular surface infection within 30 days prior to study entry.
7. Ocular surface malignancy.
8. Uncontrolled diabetes with most recent HgA1c greater than 8.5%.
9. Renal failure with creatinine clearance ≤ 25mL/min per 1.73 m2.
10. Alanine aminotransferase > 40IU/L, or aspartate aminotransferase > 40IU/L.
11. Platelet levels < 150,000 or > 450,000 per microliter.
12. Hemoglobin < 12.0 g/dL (male) or < 11.0 g/dL (female);
13. 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.
14. Pregnancy (positive test) or lactation.
15. Participation in another simultaneous medical investigation or clinical trial.
16. Severe cicatricial eye disease; Conjunctival scarring with fornix shortening.
17. Ocular comorbidities that affect the prognosis of transplantation, such as advanced glaucoma or retinal diseases.
18. Severe dry eye disease as determined by Schirmer's test < 2mm at least in one eye.
19. Any medical or social condition that in the judgment of the investigator would interfere with or serve as a contraindication to adherence to the study protocol or ability to give informed consent.
20. Signs of current infection, including fever and treatment with antibiotics.
21. Active immunological diseases.
22. History of anti-glaucoma surgeries.