Prior topical anesthesia reduces time to full cycloplegia in Chinese.
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.
Siu
A W
AW
Department of Optometry and Radiography, Faculty of Health and Social Studies, The Hong Kong Polytechnic University, Hung Hom, Kowloon.
Sum
A C
AC
Lee
D T
DT
Tam
K W
KW
Chan
S W
SW
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
D000779:Anesthetics, Local; D018727:Muscarinic Antagonists; D009883:Ophthalmic Solutions; D011343:Procaine; C005298:benoxinate; D003519:Cyclopentolate