Publication:

A quasi-experimental study to assess the effect of a local anesthetic proparacaine on tropicamide-induced pupillary dilation

Background Dilating the pupil is one of the most commonly practiced methods among ophthalmologists to examine the eye especially the posterior segment of the eye. Here we conducted a study to know the clinical effect of proparacaine, a local anesthetic, on tropicamide-induced pupillary dilation.

Methods A Quasi-experimental study was conducted on 57 subjects aged between 20 and 70 years. Study was done over a period of 3 months (February 14 - April 14) at a tertiary health care center in Bagalkot after obtaining institutional ethical committee clearance. Proparacaine was instilled in one eye (right eye) before instilling tropicamide and the other eye with a placebo (normal saline). Pupil diameter was measured using a pupillary gauge at 0, 15, and 30 mins. Results were analyzed using unpaired Student’s t-test.

Results The mean clinically efficient pupillary diameter at the end of 15 mins in proparacaine instilled eye was 5.56±0.5 and in control eye was 5.25±0.45 mm with t value 8.13 (p<0.001) which was statistically significant. And at the end of 30 mins pupillary diameter in the study group was 7.96±0.43 mm and in the control group was 7.83±0.43 mm with t value of 4.115 (p<0.001) which was also statistically significant.

Conclusions Therefore, we do recommend the use of proparacaine before instilling tropicamide for faster pupillary dilation.