Endothelial cell loss 5 years after Preserflo MicroShunt implantation: About two cases

PURPOSE: Preserflo MicroShunt is a minimally-invasive glaucoma drainage micro-tube used to shunt aqueous humor from the anterior chamber to the subtenon space. The safety of the procedure was considered satisfactory with a majority of minor side effects. OBSERVATION: We describe the 5 year endothelial cell loss after Preserflo implantation in 2 primary open angle glaucoma patients. The case 1 presented a device-cornea touch after a backward migration of the device. The case 2 presented a modified aspect of the device compatible with an inflammatory reaction. Both cases were explanted. CONCLUSION: As described in Ahmed glaucoma valve, Xen gel stent and Cypass, Preserflo MicroShunt can lead to endothelial cell loss in some cases. A long-term prospective study with pre and postoperative endothelial cell count and AS-OCT or UBM evaluation of the device positioning would be of great interest to assess the real impact of Preserflo MicroShunt and risk factors for endothelial cell loss.