Preserved corneal lamellar transplantation for infectious and noninfectious scleral defects

Abstract

Rationale : Reinforcement of thinned or necrotizing sclera has been conducted using various materials, including allogeneic sclera, allogenic cornea, amniotic membrane, fascia lata, pericardium, periosteum, and perichondrium. Among them, good outcomes have traditionally been obtained using preserved scleral grafts. However, scleral patch grafts have complications such as graft retraction, thinning, dehiscence, and necrosis. Furthermore, to promote epithelial healing, scleral patch grafting must be accompanied by procedures such as amniotic membrane transplantation (AMT) or grafting using conjunctival flaps or autografts. Recently, acellular preserved human corneas have been used in various ophthalmic surgeries, with emerging evidence supporting its use for treating scleral defects as an option that does not require AMT or conjunctival autografting. We investigated whether corneal patch grafting would show wound healing and tectonic success rate outcomes comparable to those of existing techniques.Patient presentation : Three patients presented with intractable ocular pain. Slit-lamp examination showed marked scleral thinning at the nasal side.Diagnosis : Scleral thinning progressed with conservative treatment; microbial staining and culturing were performed. Infectious or non-infectious scleritis was diagnosed according to slit-lamp examination and microbial culture results.Interventions : A preserved corneal lamellar patch was grafted at the scleral thinning area.Outcomes All patients achieved tectonic success with reduction of inflammation following corneal patch grafting. Two patients achieved complete re-epithelialization within 7 days, while 25 days were required for the third patient. No patients experienced graft thinning, rejection, or infection.Lessons : Our report suggests the feasibility of using acellular preserved human cornea patch grafts to reinforce inflammatory scleral defects and obtain successful outcomes in terms of wound healing. This technique shows a comparable tectonic success rate and superior effect on scleral defect healing without the need for adjunctive AMT or conjunctival autografting.

Application of Decellularized Porcine Sclera in Repairing Corneal Perforations and Lamellar Injuries

“…Previous research has indicated that the average time for re-epithelialization to occur is 3−4 weeks. 16 In our study, the corneal epithelium on the scleral implants gradually proliferated and differentiated into a composite epithelium within 28 days, which also confirmed the histocompatibility and repair properties of DPS. The NPS retained its cell structure.…”

“…Although DPSs do not have a basement membrane, regular preserved collagen fibers are beneficial in promoting graft survival and wound healing. Previous research has indicated that the average time for re-epithelialization to occur is 3–4 weeks . In our study, the corneal epithelium on the scleral implants gradually proliferated and differentiated into a composite epithelium within 28 days, which also confirmed the histocompatibility and repair properties of DPS.…”

“…In previous studies, preserved human corneas were applied to lamellar grafts in a rabbit model of scleral defects, and their surgical practicability was demonstrated. 15,16 With this study, we aimed to evaluate a simple decellularization process and identify whether DPS can be used to treat penetrating and lamellar corneal injuries. The main biological characteristics of DPSs, including biomechanical features and microscopic structures, were analyzed using native porcine sclera (NPS).…”

“…Regarding organizational structure, the sclera and cornea originate from the mesoderm tissues, and both are derived from neural crest cells. In previous studies, preserved human corneas were applied to lamellar grafts in a rabbit model of scleral defects, and their surgical practicability was demonstrated. , …”