title: Prior topical anesthesia reduces time to full cycloplegia in Chinese.
abstract: OBJECTIVE
  To investigate the effect of prior anesthesia on the time to full cycloplegia in young Chinese subjects.
  
  
  METHODS
  The amplitude of accommodation was monitored over a 50-minute interval after the application of 1% cyclopentolate hydrochloride with a pretreatment of 0.4% benoxinate (oxybuprocaine) or 0.9% saline solution (control). Using a nonlinear mathematical model, the rate of accommodative loss (k) and the time required for 95% of total cycloplegia (T95%) were determined.
  
  
  RESULTS
  Statistical analysis revealed a significantly faster rate of accommodative loss (P < .0001) after prior anesthesia (0.129 +/- 0.05) compared with the controls (0.103 +/- 0.04). T95% was noted at 26.43 +/- 10.22 minutes after prior anesthesia, which was significantly shorter (P < .0001) than that after the saline treatment (35.28 +/- 16.51 minutes).
  
  
  CONCLUSIONS
  Prior application of topical anesthetic can shorten the time to full cycloplegia for people, such as the Chinese, with dark irides.
authors.affiliation: Department of Optometry and Radiography, Faculty of Health and Social Studies, The Hong Kong Polytechnic University, Hung Hom, Kowloon.
authors.forename: A W
authors.initials: AW
authors.lastname: Siu
authors.forename: A C
authors.initials: AC
authors.lastname: Sum
authors.forename: D T
authors.initials: DT
authors.lastname: Lee
authors.forename: K W
authors.initials: KW
authors.lastname: Tam
authors.forename: S W
authors.initials: SW
authors.lastname: Chan
mesh_terms: D000065:Accommodation, Ocular / Q000187:drug effects* / Q000235:genetics; D000328:Adult; D000772:Anesthesia, Local; D000779:Anesthetics, Local / Q000008:administration & dosage; D044466:Asian People; D003519:Cyclopentolate / Q000008:administration & dosage*; D005127:Eye Color / Q000235:genetics; D006801:Humans; D018727:Muscarinic Antagonists / Q000008:administration & dosage*; D009883:Ophthalmic Solutions; D011343:Procaine / Q000008:administration & dosage / Q000031:analogs & derivatives; D011680:Pupil / Q000187:drug effects*; D013997:Time Factors
chemical_list: D000779:Anesthetics, Local; D018727:Muscarinic Antagonists; D009883:Ophthalmic Solutions; D011343:Procaine; C005298:benoxinate; D003519:Cyclopentolate