title: The filtering operations--past, present, and future.
mesh_terms: D002425:Cautery; D013502:General Surgery / Q000266:history*; D005901:Glaucoma / Q000266:history* / Q000601:surgery; D049672:History, 19th Century; D049673:History, 20th Century; D006801:Humans; D007498:Iris / Q000601:surgery; D012590:Sclera / Q000601:surgery; D014129:Trabecular Meshwork / Q000601:surgery