Pupil dilation using a standard cataract surgery regimen alone or with atropine 1.0% pretreatment: Prospective comparative evaluation

METHODS: In this prospective unmasked study, the baseline pupil size in eyes of volunteers was measured. Pupil size was then measured 30 minutes after instillation of the institution’s standard dilation regimen for cataract surgery, which included phenylephrine 2.5%, tropicamide 1.0%, and cyclopentolate 1.0%. Several days later, the subjects returned for repeat measurements after pretreating the study eye(s) with atropine 1.0% 3 times a day the day previously and once on the morning of repeat dilation and measurements. Pupil size was again measured after administration of the standard regimen. RESULTS:Thestudyincluded 72eyesof54patients. Apairedttestshowedastatisticallysignificant difference in mean pupil dilation between the standardregimen alone and thestandard regimen with atropine 1.0% pretreatment. The mean pupil dilation was 7.3 mm G 1.2 (SD) with the standard regimen alone and 6.9 G 1.2 mm with the standard regimen with atropine pretreatment; the difference was statistically significant (P<.001). CONCLUSION:The addition of atropine 1.0% 1 day before administration of astandard preoperative dilating regimen for cataract surgery resulted in a smaller dilated pupil diameter than administration of the standard set of preoperative mydriatic agents alone.