There was no difference in surgical success between patients with high and those with low ET-1 concentrations in aqueous humor (p = 0.715 for absolute success and p = 0.953 for relative success, log-rank (Mantel-Cox) test; Figure 4) nor between POAG and PEX glaucoma (8% versus 9.1% failure rate, data not shown). Here, EDN1 is linked to glaucoma.