title: Comparison of viscoelastic substances used in phacoemulsification.
abstract: OBJECTIVE
  To evaluate the usefulness of four viscoelastic agents during phacoemulsification: 2% hydroxypropylmethylcellulose (HPMC) (Methocel), 3% sodium hyaluronate with 4% chondroitin sulfate (Viscoat), 1% sodium hyaluronate (Healon), 1.4% sodium hyaluronate (Healon GV).
  
  
  METHODS
  Eye Clinic, Kreiskrankenhaus Bad Hersfeld, Germany.
  
  
  METHODS
  Two hundred patients, divided into four groups of 50 patients, received one of the viscoelastic substances during phacoemulsification and posterior chamber intraocular lens implantation. Patients were followed for 1 month. Visual acuity and intraocular pressure (IOP) were measured. The following were subjectively evaluated for each viscoelastic: corneal findings, anterior chamber reaction, visibility of intraocular structures and retention time during phacoemulsification, space maintaining ability, and removability and ease of injection.
  
  
  RESULTS
  Postoperative IOP and visual acuity were comparable among the four groups. Viscoat tended to trap nuclear fragments and air bubbles during the phacoemulsification procedure, which decreased visibility during surgery. Space maintenance and injection ease were significantly better with Healon and Healon GV.
  
  
  CONCLUSIONS
  The high molecular weight viscoelastics (Healon and Healon GV) performed better as viscosurgical tool during cataract surgery using phacoemulsification.
authors.affiliation: Eye Clinic Kreiskrankenhaus Bad Hersfeld, Germany.
authors.forename: W W
authors.initials: WW
authors.lastname: Hütz
authors.forename: H B
authors.initials: HB
authors.lastname: Eckhardt
authors.forename: T
authors.initials: T
authors.lastname: Kohnen
mesh_terms: D002809:Chondroitin Sulfates / Q000008:administration & dosage* / Q000009:adverse effects; D005500:Follow-Up Studies; D006801:Humans; D006820:Hyaluronic Acid / Q000008:administration & dosage* / Q000009:adverse effects; D065347:Hypromellose Derivatives; D007429:Intraocular Pressure; D007910:Lenses, Intraocular; D008747:Methylcellulose / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives*; D018918:Phacoemulsification / Q000379:methods*; D011183:Postoperative Complications; D014792:Visual Acuity
chemical_list: D065347:Hypromellose Derivatives; D006820:Hyaluronic Acid; D008747:Methylcellulose; D002809:Chondroitin Sulfates