title: Effect of Healon and Viscoat on outflow facility in human cadaver eyes.
abstract: OBJECTIVE
  To compare the acute effects of Healon (sodium hyaluronate) and Viscoat (sodium chondroitin sulfate-sodium hyaluronate) on outflow facility in human cadaver eyes and determine which viscoelastic agent is least likely to cause an intraocular pressure (IOP) spike after cataract surgery.
  
  
  METHODS
  The Glaucoma Research Lab, University of Toronto, Ontario, Canada.
  
  
  METHODS
  In this prospective paired study, 15 pairs of human cadaver eyes were used. Following the construction of a 3.0 mm scleral tunnel, 0.25 cc of Healon was injected into the anterior chamber of 1 eye and 0.25 cc of Viscoat was injected into the contralateral eye. The viscoelastic agents were removed from both eyes in a standardized fashion and the scleral tunnels closed. The eyes were then perfused at a constant IOP of 8.0 mm Hg, corresponding to 16.0 mm Hg in vivo. Outflow facility (microL/minute [min]/mm Hg) was recorded every 15 minutes for 24 hours using standard methods.
  
  
  RESULTS
  Outflow facility in the Viscoat-treated eyes decreased appreciably for the first 3 hours, then recovered somewhat after 12 hours; facility in the Healon-treated eyes showed less of an overall decrease. Over the 24 hour perfusion period, mean outflow facility was 0.037 microL/min/mm Hg +/- 0.015 (SD) in the Viscoat-treated eyes and 0.060 +/- 0.012 microL/min/mm Hg in the Healon-treated eyes. Healon reduced outflow facility significantly less than Viscoat between 3.25 and 10.50 hours postoperatively (P < .05, 2-tailed t test).
  
  
  CONCLUSIONS
  Healon reduced outflow facility less than Viscoat between 3.25 and 10.50 hours postoperatively.
authors.affiliation: Department of Ophthalmology, University of Toronto, Canada.
authors.forename: D
authors.initials: D
authors.lastname: Lane
authors.forename: M
authors.initials: M
authors.lastname: Motolko
authors.forename: D B
authors.initials: DB
authors.lastname: Yan
authors.forename: C R
authors.initials: CR
authors.lastname: Ethier
mesh_terms: D000867:Anterior Chamber / Q000187:drug effects* / Q000378:metabolism; D001082:Aqueous Humor / Q000378:metabolism*; D002102:Cadaver; D002807:Chondroitin / Q000494:pharmacology*; D002809:Chondroitin Sulfates; D004338:Drug Combinations; D005260:Female; D006801:Humans; D006820:Hyaluronic Acid / Q000494:pharmacology*; D066298:In Vitro Techniques; D007267:Injections; D007429:Intraocular Pressure / Q000187:drug effects*; D008297:Male; D011446:Prospective Studies; D013997:Time Factors; D014129:Trabecular Meshwork / Q000187:drug effects* / Q000378:metabolism
chemical_list: D004338:Drug Combinations; C501944:chondroitin sulfate, sodium hyaluronate drug combination; D006820:Hyaluronic Acid; D002807:Chondroitin; D002809:Chondroitin Sulfates