title: Viscoanaesthesia in cataract surgery: a prospective, randomized clinical trial.
abstract: OBJECTIVE
  We aimed to compare viscoanaesthesia (VisThesia) with intracameral lidocaine in cataract surgery carried out under topical anaesthesia.
  
  
  METHODS
  In this prospective study 98 patients were randomly assigned to receive VisThesia (group 1, n = 49) or 0.5 cc of 1% unpreserved lidocaine (group 2, n = 49). All surgery was carried out by one surgeon using clear corneal technique. Pachymetry, the status of the cornea and anterior chamber, and intraocular pressure (IOP) were checked pre- and postoperatively.
  
  
  RESULTS
  Mean pain scores were 0.12 (maximum: 3) in group 1 and 0.37 in group 2; the difference between the groups was not statistically significant (95% confidence interval [CI] 0.003-0.487; p = 0.05). A total of 48 patients in group 1 (98%) and 49 in group 2 (100%) reported no discomfort or only mild discomfort. No significant differences in flare and cells in the anterior chamber or IOP were found between the two study groups. There was a significantly greater frequency of corneal oedema in group 1 (p = 0.001). Postoperative central corneal thickness values were also significantly higher in group 1 (95% CI 11.64-57.24; p = 0.003).
  
  
  CONCLUSIONS
  Results suggest that viscoanaesthesia provides a level of comfort during cataract surgery under topical anaesthesia similar to that facilitated by intracameral lidocaine. However, patients who are given viscoanaesthesia may have increased risk for postoperative corneal oedema.
authors.affiliation: Department of Ophthalmology, Lahti Central Hospital, Keskussairaalankatu 7, Lahti, Finland. juha.valimaki@phsotey.fi
authors.forename: Juha
authors.initials: J
authors.lastname: Välimäki
authors.forename: Riikka-Maija
authors.initials: RM
authors.lastname: Törnblom
mesh_terms: D000287:Administration, Topical; D000368:Aged; D000369:Aged, 80 and over; D000772:Anesthesia, Local / Q000379:methods*; D000779:Anesthetics, Local / Q000008:administration & dosage*; D002387:Cataract Extraction / Q000009:adverse effects / Q000295:instrumentation; D015715:Corneal Edema / Q000209:etiology; D004338:Drug Combinations; D005123:Eye; D005260:Female; D006801:Humans; D006820:Hyaluronic Acid / Q000008:administration & dosage*; D007267:Injections; D008012:Lidocaine / Q000008:administration & dosage*; D008297:Male; D008875:Middle Aged; D010149:Postoperative Pain / Q000503:physiopathology
chemical_list: D000779:Anesthetics, Local; D004338:Drug Combinations; D006820:Hyaluronic Acid; D008012:Lidocaine