Topical Anesthesia for Closed PKP vs Retrobulbar Anesthesia for Open-sky PKP

Study Overview
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Brief Summary
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Penetrating keratoplasty (PKP) is an open-sky surgery that fundamentally has not changed for more than 100 years. Because conventional PKP is associated with the potential for the development of devastating complications such as expulsive suprachoroidal hemorrhage and endophthalmitis, we modified the technique to one that is a closed surgery under topical anesthesia with the anterior chamber maintained to achieve favorable results. Topical anesthesia is an attractive alternative to traditional injection local anesthesia since the potentially serious complications associated with retrobulbar and peribulbar anesthesia can be avoided. The closed PKP procedure with the stable anterior chamber essentially changes the open nature of conventional PKP. The advantages, i.e., decreased surgical risks, postoperative complications, and surgical difficulties, make PKP viable in most complicated cases.

Conditions
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Corneal Opacity, Keratitis, Herpetic, Corneal Ulcer, Corneal Dystrophies, Hereditary

Intervention / Treatment
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* Procedure: closed PKP under topical anesthesia
* Procedure: open-sky PKP under retrobulbar anesthesia
* Drug: Anti-Rejection Agents
* Drug: Anti-Inflammatory Agents


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: active bacterial keratitis, for which ulceration progressed despite maximum antibacterial medication; refractory fungal keratitis that did not respond to antifungal agents; nonactive HSK, for which corneal opacities with or without new vessels involved the optical zone; ocular acid burn and thermal burn with partial limbal deficiency (50% or less) that, after more than half a year of preoperative treatment, showed reepithelialization and less than 2 quadrants limbal neovascularization. Exclusion Criteria: Patients with keratolimbal allograft transplantation, total limbal stem cell deficiency secondary to ocular burns, and other ocular diseases (ie, amblyopia, age-related cataract, glaucoma, macular edema, and mac ular degeneration) were excluded.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 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: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: closed PKP under topical anesthesia<br>a closed corneal transplantation under topical anesthesia with the anterior chamber maintained | Procedure: closed PKP under topical anesthesia<br>* a closed corneal transplantation under topical anesthesia with the anterior chamber maintained<br>Drug: Anti-Rejection Agents<br>* Anti-Rejection Agents for both groups<br>Drug: Anti-Inflammatory Agents<br>* Anti-Inflammatory Agents for both groups<br>|
| Active Comparator: open-sky PKP under retrobulbar anesthesia<br>an open-sky corneal transplantation under retrobulbar anesthesia | Procedure: open-sky PKP under retrobulbar anesthesia<br>* an open-sky corneal transplantation under retrobulbar anesthesia<br>Drug: Anti-Rejection Agents<br>* Anti-Rejection Agents for both groups<br>Drug: Anti-Inflammatory Agents<br>* Anti-Inflammatory Agents for both groups<br>|
| Other: Anti-Rejection Agents<br>Anti-Rejection Agents for both groups | Procedure: closed PKP under topical anesthesia<br>* a closed corneal transplantation under topical anesthesia with the anterior chamber maintained<br>Procedure: open-sky PKP under retrobulbar anesthesia<br>* an open-sky corneal transplantation under retrobulbar anesthesia<br>|
| Other: Anti-Inflammatory Agents<br>Anti-Inflammatory Agents for both groups | Procedure: closed PKP under topical anesthesia<br>* a closed corneal transplantation under topical anesthesia with the anterior chamber maintained<br>Procedure: open-sky PKP under retrobulbar anesthesia<br>* an open-sky corneal transplantation under retrobulbar anesthesia<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| best corrected visual acuity |  | preoperative | 
| best corrected visual acuity |  | 1 week after PKP | 
| best corrected visual acuity |  | 2 weeks after PKP | 
| best corrected visual acuity |  | 1 month after PKP | 
| best corrected visual acuity |  | 3 months after PKP | 
| best corrected visual acuity |  | 6 months after PKP | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Endothelial cell density |  | 1 week after PKP | 
| Endothelial cell density |  | 2 weeks after PKP | 
| Endothelial cell density |  | 1 month after PKP | 
| Endothelial cell density |  | 3 months after PKP | 
| Endothelial cell density |  | 6 months after PKP |