Are Descemet Membrane Ruptures the Root Cause of Corneal Hydrops in Keratoconic Eyes?

To challenge the current consensus on the mechanism causing corneal hydrops in eyes with keratoconus (KC).Retrospective, interventional case series.Sixteen eyes of 10 patients with comorbid KC and Fuchs endothelial corneal dystrophy (FECD) underwent uncomplicated Descemet membrane endothelial keratoplasty (DMEK), and 5 eyes of 5 patients with KC alone underwent Bowman layer (BL) transplantation complicated by inadvertent perforation of the posterior corneal stroma and Descemet membrane (DM). The presence or absence of hydrops was assessed by intra- and postoperative optical coherence tomography and by slit-lamp biomicroscopy.None of the 16 DMEK eyes manifested a hydrops at any time during or after surgery. By contrast, all 5 eyes undergoing BL transplantation complicated by posterior corneal perforation demonstrated a corneal hydrops, evident both intra- and postoperatively.In eyes with KC, even the complete removal of DM did not produce a hydrops, whereas a combined defect in DM and the posterior corneal stroma seemed to consistently elicit a typical corneal hydrops.