Changes in central corneal thickness values after instillation of oxybuprocaine hydrochloride 0.4%.
OBJECTIVE
To assess the variation in central corneal thickness (CCT) following the instillation of oxybuprocaine hydrochloride (0.4%), in normal subjects.


METHODS
This was a randomized, prospective study of CCT measurements (before and after the instillation of topical anaesthesia) obtained with the Topcon SP-3000P noncontact specular microscope, in 60 eyes of thirty subjects. The subjects' mean age was 20±1 years (mean±SD). In each subject, one eye was treated with one drop of oxybuprocaine hydrochloride (HCl) and the fellow eye with one drop of normal saline (control). The SP-3000P CCT readings were first obtained before instillation (baseline) and monitored every 30 s after instillation of each eye drop for a period of 10 min.


RESULTS
The mean baseline CCT for oxybuprocaine was 526±23 μm. Ten minutes after, it was 526±24 μm. In the control, the mean CCT was 526±27 μm, 10 min after it was 526±28 μm. The mean variation in CCT measurement was -0.7±3.1 (5.5 to -6.8 μm, 95% CI) for oxybuprocaine and -0.6±4.1 μm (7.5 and -8.6 μm, 95% CI) for the fellow eyes (P>0.05). There was no significant variation among the 20 CCT columns for either oxybuprocaine or the control group (P>0.05 for both).


CONCLUSIONS
One drop of topical oxybuprocaine 0.4% did not cause a significant change in CCT at up to 10 min following instillation. However, higher differences were observed at 2.30 min and 4.30 min after instillation.
Department of Optometry & Vision Science, College of Applied Medical Sciences, King Saud University, P.O. Box 10219, Riyadh 11433, Saudi Arabia.
Kelechi C
KC
Ogbuehi
John C
JC
Chijuka
Uchechukwu L
UL
Osuagwu
D000328:Adult; D000779:Anesthetics, Local / Q000008:administration & dosage; D003315:Cornea / Q000033:anatomy & histology* / Q000187:drug effects*; D019781:Corneal Topography / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008853:Microscopy / Q000379:methods*; D009887:Ophthalmoscopy / Q000379:methods*; D009929:Organ Size / Q000187:drug effects*; D011343:Procaine / Q000008:administration & dosage / Q000031:analogs & derivatives*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D055815:Young Adult
D000779:Anesthetics, Local; D011343:Procaine; C005298:benoxinate