title: Oxidative tissue damage after phacoemulsification: influence of ophthalmic viscosurgical devices.
abstract: OBJECTIVE
  To quantify the oxidative tissue damage after phacoemulsification, correlate the damage to the energy applied, and investigate the influence of ophthalmic viscosurgical devices (OVDs).
  
  
  METHODS
  Department of Ophthalmology, University of Mainz, Mainz, Germany.
  
  
  METHODS
  The study comprised 130 eyes operated on by 1 surgeon using the same phacoemulsification machine. Some eyes received an OVD before phacoemulsification and some did not. Energy values were expressed as phaco time; that is, ultrasound (US) time (seconds) after conversion to 100% phaco power. Patients were grouped as follows: Group 1, phaco time less than 20 seconds and no OVD; Group 2, phaco time 20 to 40 seconds and no OVD; Group 3, phaco time more than 40 seconds and no OVD; Group 4, phaco time 20 to 40 seconds and hydroxypropyl methylcellulose 2% (HPMC); Group 5, phaco time 20 to 40 seconds and sodium hyaluronate 1%. Aqueous humor from pseudophakic eyes served as a control. At the end of surgery, anterior chamber fluid was analyzed for lipid peroxides using the thiobarbituric acid method.
  
  
  RESULTS
  Lipid peroxides were detected in all groups. The values were significantly higher in Group 2 than in Group 1 (P<.01) and in Group 3 than in Groups 1 and 2 (P<.01). The differences in lipid peroxide values between all phaco groups and the control group were statistically significant. Sodium hyaluronate 1% and HPMC 2% produced significantly lower lipid peroxide values than in the respective phaco groups that did not receive an OVD (both P<.01).
  
  
  CONCLUSIONS
  Oxidative tissue damage occurred during phacoemulsification. The damage, which correlated with the US energy applied, can be reduced by the use of OVDs.
authors.affiliation: Department of Ophthalmology, Klinikum Karlsruhe, Germany. 106020.560@compuserve.com
authors.forename: Albert J
authors.initials: AJ
authors.lastname: Augustin
authors.forename: H Burkhard
authors.initials: HB
authors.lastname: Dick
mesh_terms: D000368:Aged; D001082:Aqueous Humor / Q000378:metabolism; D016166:Free Radical Scavengers / Q000627:therapeutic use; D005609:Free Radicals; D006801:Humans; D006820:Hyaluronic Acid / Q000627:therapeutic use; D007785:Lactose / Q000031:analogs & derivatives* / Q000627:therapeutic use; D015227:Lipid Peroxidation; D008054:Lipid Peroxides / Q000378:metabolism; D008747:Methylcellulose / Q000031:analogs & derivatives* / Q000627:therapeutic use; D010078:Oxazines; D018384:Oxidative Stress; D018918:Phacoemulsification / Q000009:adverse effects*; D011183:Postoperative Complications; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism
chemical_list: D016166:Free Radical Scavengers; D005609:Free Radicals; D008054:Lipid Peroxides; D010078:Oxazines; D017392:Thiobarbituric Acid Reactive Substances; D006820:Hyaluronic Acid; D008747:Methylcellulose; C071191:MK 458; D007785:Lactose