Corneal endothelial cell loss after Baerveldt glaucoma drainage device implantation in the anterior chamber

PURPOSE To investigate central and peripheral corneal endothelial cell density (ECD) in relation to Baerveldt (BV) glaucoma drainage device (GDD) tube corneal (TC) distance. METHODS Prospective study of all patients scheduled for glaucoma tube surgery with 36 months follow-up. A BV GDD was inserted into the anterior chamber (AC). Anterior segment optical coherence tomography (AS-OCT) scans were made to determine the TC distance. Central and peripheral ECD was measured, preoperatively and at 3, 6, 12, 24 and 36 months postoperatively. RESULTS Fifty-three eyes were included [primary open-angle glaucoma, (n = 13); secondary glaucoma, (n = 30); and primary angle-closure glaucoma, (n = 10)]. Central ECD significantly decreased during follow-up, with a mean decrease of 4.54% per year (p < 0.001), and 6.57% in the peripheral quadrant closest to the BV GDD tube (PQC, p < 0.001). In the PQC, a yearly decrease of 1.57% was shown after transiridial tube placement versus 7.43% after placement 'free' into the AC (p = 0.006). Endothelial cell (EC) loss was related to TC distance (mean 1.69 mm), with a central loss of 6.20% and 7.25% in the PQC per year with shorter TC distances, versus a central loss of 4.11% and 5.77% in the PQC per year with longer TC distances (outside mean ± 2SD, p < 0.001). A difference in EC loss by glaucoma subtype was not identified. CONCLUSION The TC distance is of significant influence on corneal ECD, a shorter TC distance causing more severe EC loss, especially in the PQC. Transiridial placement of the BV GDD tube seems safer than placement 'free' into the AC.