Prospective Study of Deep Anterior Lamellar Keratoplasty Using Acellular Porcine Cornea

Study Overview
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Brief Summary
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The performance of keratoplasty is hampered by the limited availability of donor cornea in many countries, especially in Asia. For this reason, attempts have been made to fabricate artificial substitutes for natural human cornea. So far, all polymeric biomaterials, such as collagen configurations and plastic compression, could mimic the functional optically transparent but failed to replicate the complicate three-dimension microstructure of natural cornea. Therefore, despite some favorable results yielded by polymeric biomaterials, they cannot be suited for long-term use. To overcome these disadvantages, in recent years, porcine cornea appeared specifically attractive for xenotransplantation, because of its accessibility and similarities to natural human cornea. However, xenotransplantation using fresh porcine cornea can occurs hyperacute immune rejection, resulting in graft failure. Such transplant rejection can be substantially lessened by using acellular porcine cornea (APC), which preserves the constructure of natural cornea, whilst having well biocompatibility and low antigenicity. These properties feature APC particularly suitable for high-risk keratoplasty, such as corneal grafting in infectious keratitis. Use of APC in LK has been shown promise in many preclinical animal studies and initially in human clinic trail. However, to optimize APC biological and biomechanical properties, the strategies for its preparation has evolved extensively over recent years, like various decellularization approaches (e.g. detergents, enzymes, human sera, hypertonic solutions and et al) and additional procedures (e.g. collagen re-crosslinking and repeated frozen-dry). Therefore, in the current study, the investigators analyzed the early surgical outcomes of deep anterior lamellar keratoplasty (DALK) using the APC that was very recently approved by the National Institutes for Food and Drug Control (NIFDC) of China for clinic practice, for management of infective keratitis, including fungal, viral and acanthamoeba keratitis. Here major concern of this study was to clarify the behavior of APC after implantation in participants.

Official Title
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Prospective Study of Deep Anterior Lamellar Keratoplasty Using Acellular Porcine Cornea

Conditions
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Corneal Transplantation

Intervention / Treatment
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* Procedure: Deep anterior lamellar keratoplasty
* Device: Acellular Porcine Cornea
* Drug: Tacrolimus eye drops
* Drug: Tobradex eyedrops


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: corneal diseases not involving the endothelial layer Exclusion Criteria: corneal diseases involving the endothelial layer allergic to pig tissue do not accept xenotransplantation
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
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Acellular porcine cornea group<br>Participants with corneal diseases not involving the endothelial layer undergo deep anterior lamellar keratoplasty using acellular porcine cornea | Procedure: Deep anterior lamellar keratoplasty<br>* Deep anterior lamellar keratoplasty using acellular porcine cornea; 0.05%Tacrolimus eye drops, four times a day for at least one year; 0.3% Tobradex eyedrops, four times-one times a day for one year.<br>Device: Acellular Porcine Cornea<br> <br> Drug: Tacrolimus eye drops<br> <br> Drug: Tobradex eyedrops<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the changes of Best corrected visual acuity |  | Before surgery, 1-week, 1-month, 3-month, 6-month, 1-year, 2-year, 3-year, 4-year after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the changes of visual contrast sensitivity |  | Before surgery, 3-month, 6-month, 1-year, 2-year, 3-year, 4-year after surgery | 
| the changes in the transparency of graft | using Slit lamp microscopic evaluation | 1-week, 1-month, 3-month, 6-month, 1-year, 2-year, 3-year, 4-year after surgery | 
| The changes in corneal thickness depth | using anterior segmental OCT | 1-week, 1-month, 3-month, 6-month, 1-year, 2-year, 3-year, 4-year after surgery | 
| The changes in corneal nerve regeneration | using Confocal microscopy | 1-month, 3-month, 6-month, 1-year, 2-year, 3-year, 4-year after surgery | 
| The changes of depression and anxiety status | Using Self-Rating Depression Scale (SDS) and Self-Rating Anxiaty Scale (SAS) | Before surgery, 1-month, 3-month, 6-month, 1-year, 2-year, 3-year, 4-year after surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Bioegineered cornea, Corneal Transplantation, Xenotransplantation