title: Influence of non-penetrating glaucoma surgery on aqueous outflow facility in isolated porcine eyes.
abstract: OBJECTIVE
  To investigate, in vitro, the influence of non-penetrating glaucoma surgery (NPGS) and the influence of tightly suturing the superficial scleral flap on the aqueous outflow facility of isolated porcine eyes.
  
  
  METHODS
  The anterior chambers of 12 enucleated porcine cadaver eyes were cannulated and perfused. NPGS was performed by the same surgeon. The overall ocular aqueous outflow facilities were assessed before and after the surgical interventions of NPGS, as well as after scleral flap closure.
  
  
  RESULTS
  The mean (SD) aqueous outflow facility, which was 0.164 (0.014) microl/min/mm Hg before surgery, increased significantly after NPGS to 1.584 (0.217) microl/min/mm Hg, p<0.001. When the superficial flap was closed, the aqueous outflow facility significantly decreased (0.754 (0.107) microl/min/mm Hg, p<0.001) but remained significantly higher than preoperatively (p<0.01). After suturing the superficial flap, the overall resistance increased to 1.625 (0.210) microl/min/mm Hg. The difference in the resistance to outflow before and after flap closure was 0.848 (0.169) microl/min/mm Hg.
  
  
  CONCLUSIONS
  After NPGS suturing the scleral flap can modulate aqueous outflow resistance. The experimental set up described might provide an efficient model for the technical training of glaucoma surgeries.
authors.affiliation: University Eye Hospital, Basel, Switzerland. shaarawy@glaucoma-surgery.com
authors.forename: T
authors.initials: T
authors.lastname: Shaarawy
authors.forename: R
authors.initials: R
authors.lastname: Wu
authors.forename: A
authors.initials: A
authors.lastname: Mermoud
authors.forename: J
authors.initials: J
authors.lastname: Flammer
authors.forename: I O
authors.initials: IO
authors.lastname: Haefliger
mesh_terms: D000818:Animals; D000867:Anterior Chamber / Q000601:surgery; D001082:Aqueous Humor / Q000502:physiology*; D015353:Eye Enucleation / Q000379:methods; D005901:Glaucoma / Q000503:physiopathology / Q000601:surgery*; D012590:Sclera / Q000601:surgery; D013524:Surgical Flaps; D013537:Sutures; D013552:Swine