Accelerating progress in biomedical engineering1 and the ability to live image and understand delicate outflow structures2 have produced an abundance of new surgical options in the last few years for an ancient disease that stubbornly defies the best hands and minds. Glaucoma, first described by Hippocrates 400 BC as vision loss in the elderly that is different from cataract,3 is now a leading cause of irreversible blindness with increasing prevalence in an aging population.4 Despite the many new arrivals, the concepts behind recent names like Trabectome,5 iStent,6 Hydrus,7 Xen,8 Solx,9 Cypass,10 Canaloplasty,11 ECP12 are not entirely new: open angle glaucoma has been surgically treated for 150–100 years by either increasing external filtration,13 internal filtration (angle surgery;14 suprachoroidal drainage15) or ciliodestruction.16

Development of new devices and technologies was spurred by the realisation that the standard surgeries performed today for glaucoma—trabeculectomy and epibulbar glaucoma drainage device surgery—have unacceptably high failure and complication rates even when performed as primary surgeries.17 While not as rudimentary and unsuccessful as at the time of their inception in the form of guarded external filtration by Sugar in 1962,18 or the gold wire shunt by De Wecker in 1876,19 both present iterations seem almost as primitive given that urgent postoperative interventions have to be performed in astonishing 74% of trabeculectomies and 27% of tube shunts.20 Serious, vision-threatening early postoperative complications occur in 39% of trabeculectomy and 22% of tube shunt patients, while additional serious complications during 5-year follow-up occur in 38% …