XEN45 location parameters and association with endothelial cell count change
endothelial cell loss
ADVERSE EVENTS, CORNEA
The distance of the Ahmed tube tip to the cornea has a significant association with endothelial cell loss in the quadrant of implantation [Surprisingly, the placement of the XEN45 implant in the anterior chamber angle (e.g., more anterior near the Schwalbe line, more posterior near the scleral spur) and the distance of inner ostium to cornea had no statistically significant influence on the course of central endothelial cell count after XEN45 implantation.Further to this, after Ahmed valve implantation, the lowest endothelial cell count was recorded at the site of implantation, suggesting that the silicone tube of the Ahmed valve locally reduces endothelial cell counts [Therefore, the tolerance zone of implantation seems to be large with regard to central endothelial cell loss, possibly giving the surgeon more freedom in terms of positioning the implant at the chamber angle. Despite these findings, we recommend being cautious when choosing the site of implantation, i.e., not implanting too anterior or posterior, as placement could influence other factors (e.g., efficacy and safety: IOP outcome, revision rates, re-surgery rates, needling rates, and the rate of adverse events).