EDN1 and open-angle glaucoma: Second, the destruction of the blood-aqueous barrier in PXG eyes after trabeculectomy is more serious than that in POAG, the levels of transforming growth factor beta (TGF-β) and endothelin-1 in aqueous humor increase, and iris angiopathy and systemic angiopathy are also involved, all of which will have an influence on the postoperative effects of trabeculectomy [18].