Urate deposition in the iris and anterior chamber.

OBJECTIVE: To report on a patient with clear gelatinoid deposits on the iris and in the anterior chamber (AC). DESIGN: Observational case report. METHODS: Examination of AC aspirate and iris and conjunctival biopsies by light and transmission electron microscopy. MAIN OUTCOME MEASURES: Clinical and histopathological findings. RESULTS: Analysis of the aqueous humor and iris ultrastructure disclosed the presence of urate deposits. CONCLUSIONS: Urate deposition in the iris and anterior chamber rarely occurs.

A technique to harvest Descemet's membrane with viable endothelial cells for selective transplantation.

PURPOSE: To describe a surgical technique using an artificial anterior chamber to facilitate harvest of Descemet's membrane (DM) and endothelium for corneal endothelial cell transplantation. DESIGN: Laboratory investigation. METHODS: Corneoscleral buttons of seven human donor eyes were mounted endothelial side up on an artificial anterior chamber. Keeping the endothelial side with its usual concavity, a manual trephination was made on the posterior surface with a 9.0-mm trephine, inside the Schwalbe line and just past the DM in depth. The chamber was filled with air, causing the endothelial side of the donor cornea to assume a convex configuration. The DM along with its endothelium was separated from the posterior stroma using a blunt cyclodialysis spatula. Drops of trypan blue 0.3% and alizarin red S 0.2% (n = 6) were applied. The stained DMs were examined under a light microscope and photographed to calculate the percentage of endothelial cell damage. Histology was done on the unstained cornea. RESULTS: The DM carrying endothelium was successfully removed from the posterior stroma in all seven eyes. Although the DM appears to be very friable, all samples were removed in toto without rupture. Vital staining showed a mean endothelial cell loss of 8.46% (standard deviation (SD) 6.9). Direct light microscopy demonstrated the preservation of endothelial cell morphology. CONCLUSIONS: This technique appears to be a safe and straightforward method to harvest DM for endothelial cell transplantation. Further studies are underway to determine the optimal method of insertion of the obtained healthy DM with endothelial cells through small corneal incisions.