Corneal graft failure following Nd:YAG laser membranotomy for inadvertent retained descemet's membrane after penetrating keratoplasty.

Retained Descemet's membrane (DM) following penetrating keratoplasty (PKP) is a rare finding that may reduce visual acuity following opacification or endanger the graft endothelium. The association between Nd:YAG laser membranotomy and corneal graft failure is reported. Five of 1,350 patients (0.37%) undergoing PKP for pseudophakic bullous keratopathy or graft failure between 1986 and 2008 presented with inadvertent retained DM located close to the graft endothelium. The membrane opacified within 3 to 4 months, reducing the patients' vision. Nd:YAG laser membranotomy was performed using low energy and few pulses. Patients' visual acuity improved from 6/40 to 6/90 before treatment to 6/15(-) to 6/20 at 2 weeks following membranotomy. However, the corneal graft decompensated within 6 to 8 weeks following this procedure, necessitating repeat PKP, with removal of the retained DM. Nd:YAG laser membranotomy may lead to corneal graft failure due to shockwave damage created by the laser pulses, focused near the endothelial surface.