Treatment of perforated cornea with an autologous lamellar scleral graft: histologic findings / Tratamento de córnea perfurada com enxerto autônomo de esclera lamelar: achados histológicos

ABSTRACT We report a case of central corneal perforation treated with an autologous lamellar scleral graft and histologic findings obtained after a subsequent penetrating keratoplasty. A corneal perforation within a large Pseudomonas ulcer in a 55-year-old male rigid gas permeable contact lens wearer was sealed by a lamellar scleral graft from the same eye, followed by an uneventful penetrating keratoplasty 6 months later. Histology of the excised button revealed that the well-apposed graft, which maintained the irregular arrangement of the scleral collagen fibers, was embedded in the corneal stroma over the deep blood vessels and a rupture in Descemet's membrane. The clinical and histologic findings showed that autologous lamellar scleral grafts can be successfully used for the emergency treatment of corneal perforation when a corneal transplant is not available. The distinctive scleral structure revealed by histology and the inadequate graft transparency indicate that visual rehabilitation of eyes with a central corneal perforation can be achieved only by a subsequent optic penetrating keratoplasty.

RESUMO Relatamos um caso de perfuração corneana central tratada com enxerto autólogo lamelar de esclera e os achados histológicos obtidos após ceratoplastia penetrante (CP) subsequente. Uma perfuração da córnea devido a uma grande úlcera por Pseudomonas em um usuário de lentes de contato rígidas gás permeável de 55 anos de idade foi selada por um enxerto escleral lamelar do mesmo olho, seguida de ceratoplastia penetrante, sem intercorrências, seis meses depois. A histologia do botão excisado revelou que um enxerto bem posicionado, que manteve o arranjo irregular das fibras de colágeno escleral, foi incorporado no estroma corneano sobre os vasos sanguíneos profundos e uma ruptura na membrana de Descemet. Os achados clínicos e histológicos demonstraram que o enxerto autônomo de esclerose lamelar pode ser usado com sucesso como tratamento de emergência da perfuração da córnea, quando o transplante de córnea não é possível. A estrutura escleral característica revelada pela histologia e a transparência inadequada do enxerto indicam que a reabilitação visual dos olhos com uma perfuração corneana central só pode ser alcançada através de uma ceratoplastia penetrante óptica subsequente.

Tectonic Lamellar Keratoplasty Using Cryopreserved Cornea in a Large Descemetocele

We describe herein a case of an impending corneal perforation with a large descemetocele in a patient with previous penetrating keratoplasty (PKP) that subsequently was treated with an emergent lamellar keratoplasty using frozen preserved cornea. A 76-year-old male patient, who had a PKP, presented with a completely whitish and edematous graft accompanied by large epithelial defects. Although antibiotics and antiviral agents were tried for three days, the corneal stroma abruptly melted, except for the Descemet's membrane and endothelium. Cryopreserved corneal tissue that was kept at -80degrees C was thawed and sutured on top of the remaining Descemet's membrane and endothelium. Pathological and microbiological tests were conducted using the remaining donor and recipient corneal tissues. After tectonic corneal transplantation on top of a large descemetocele, a healthy graft and relatively clear interfaces between graft-host junctions were maintained without serious adverse reactions throughout 6 month follow-up period. Microbiological evaluations of donor tissue at the time of thawing and tissue preparation were done, and the results were all negative. Tissue that was taken intraoperatively from the recipient cornea also showed negative microbiological results. In conclusion, tectonic lamellar keratoplasty, using cryopreserved corneal tissue, only onto the remaining Descemet's membrane and endothelium in an emergent condition, was a safe and effective treatment.

Tectonic Deep Anterior Lamellar Keratoplasty in Impending Corneal Perforation Using Cryopreserved Cornea

We report a case of tectonic corneal transplantation for impending corneal perforation to preserve anatomic integrity using cryopreserved donor tissue. An 82-year-old woman exhibiting impending corneal perforation suffered from moderate ocular pain in the left eye for one week. After abnormal tissues around the impending perforation area were carefully peeled away using a Crescent blade and Vannas scissors, the patient received tectonic deep anterior lamellar keratoplasty using a cryopreserved cornea stored in Optisol GS(R) solution at -70degrees C for four weeks. At six months after surgery, the cornea remained transparent and restored the normal corneal thickness. There were no complications such as corneal haze or scars, graft rejection, recurrent corneal ulcer, and postoperative rise of intraocular pressure. Cryopreserved donor lamellar tissue is an effective substitute in emergency tectonic lamellar keratoplasty, such as impending corneal perforation and severe necrotic corneal keratitis.