A Novel Suture-Guided Posterior Lamellar Keratoplasty Technique for Insertion of Thin Posterior Lamellar Grafts

Abstract

Purpose:: To develop a new posterior lamellar keratoplasty technique, reducing the risk of graft dislocation and utilizing suture-guidance, for insertion and stabilization of thin posterior lamellar grafts.

Methods:: The study is a laboratory investigation.

Results:: Donor human corneas were obtained from the Medical Eye Bank of Maryland, Central Florida Lions Eye Bank, and the Donor Network of Arizona. Corneoscleral buttons were placed endothelial side down on an artificial anterior chamber (ALTK System, Moria, Antony, France), and a novel technique (outlined below) for the optimal insertion of Descemet’s membrane with endothelial cells through small corneal incisions was developed.Initially, Descemet’s membrane was removed for preparation of a recipient stromal bed. Once the recipient stromal bed had been prepared, a double-armed 10.0 prolene or nylon suture on a long CTC needle was placed through 2 peripheral points at the leading edge of a thin corneal endothelium graft with Descemet’s membrane plus minimal stromal carrier tissue. Each arm of the suture was then passed through a 3mm clear corneal incision into a human cornea, previously stripped of Descemet’s and endothelium in a central 9mm zone, mounted onto an artificial anterior chamber and out through clear cornea near the ideal posterior graft placement site 180 degrees opposite to the incision. The 2 needles were separated by a width greater than the distance of separation of the sutures in the graft to avoid wrinkling upon graft insertion. The respective grafts were then folded and placed through the small corneal incision into the anterior chamber by gently pulling on the guiding sutures. After the endothelial grafts were in good position and buoyed up against the posterior stroma over an air bubble, the guiding suture was cut and removed. The corneal incision was sutured closed.Outcome Measures: The major outcome measured was endothelial viability assessed by trypan blue and alizarin red staining. Endothelial cell loss was assessed and samples were evaluated under a light microscope (200× magnification).

Conclusions:: Descemet's stripping with endothelial keratoplasty is a promising new corneal transplant procedure that provides rapid visual recovery and predictable refractive outcomes. We have developed an improved surgical technique for the optimal insertion of endothelial cells through small corneal incisions.

Keywords: cornea: basic science • cornea: endothelium • transplantation