Does central descemet’s membrane leak fluid?

Abstract

Based on experience with maximal-depth lamellar keratoplasty with extensive baring of Descemet's membrane, Dr. Teichmann recently stated that Descemet's membrane (with an intact endothelium) does not visibly leak fluid from the interior of the eye.1 He concluded that the tiny Descemet's window that is exposed during viscocanalostomy and related procedures would be insufficient to allow significant amounts of aqueous outflow, unless the peripheral portion of Descemet's, near Schwalbe's line, behaves differently from more central Descemet's. Does central Descemet's membrane leak fluid? Approximately 1 year ago, we tried to answer this question. We performed maximal-depth lameller keratoplasty in patients who were having penetrating keratoplasty. Initially, we observed no leakage. Examination of the remaining layer under light microscopy in these cases revealed that there was still some stromal tissue on Descemet's membrane, and this layer was too thick for leakage. Complete baring of Descemet's membrane was very difficult; most of the efforts resulted in perforation of the membrane. Then we decided to modify our technique. Paracentesis was performed from the limbus to minimize the risk of perforation, and balanced salt solution was injected gently between the remaining stromal fibers and Descemet's membrane to facilitate the peeling. With this technique, complete baring of Descemet's membrane was achieved and aqueous diffusion through central Descemet's membrane was observed. Therefore, we believe that Descemet's window plays an important role in aqueous percolation in the viscocanalostomy procedure. Kaan Unlu MD Fikret Akata MD aDiyarbakir, Turkey bAnkara, Turkey