Efficacy of topical tropicamide 1% versus a combination of tropicamide 0.8% and phenylephrine 5% for cycloplegia

Background: In ophthalmic practice, cycloplegia were required on a regular basis for refraction and fundus evaluation. A well dilated pupil helps the refraction to be carried out more easily and accurately, and also allows a thorough examination of the lens and fundus. Objective: To compare 1% tropicamide solution with a combination of 0.8% tropicamide and 5% phenylephrine for the degree of cycloplegia and the amount of residual accommodation at 20 minutes after instillation of the drop. Methods: In this prospective, randomized study, 150 patients who presented to the department of Ophthalmology were evaluated for cycloplegia. They received 1 deop of Tropicamide 1% in one eye and the combination drop in the other eye. The cyclopleiga and residual accommodation were assessed at 20 minutes using the autorefractometer. Results: In the eyes that received Tropicamide 1%, the mean cycloplegia measured at 20 minutes was 1.12 D and the mean residual accommodation was 1.20 D. In the eyes that received the combination drop, the mean cycloplegia was 1.05 D and the mean residual accommodation was 1.26 D. Though the cyclopegic effect of tropicamide 1% was marginally better than the combination drop, the difference in the two groups was not statistically significant for cycloplegia (p=0.07) or residual accommodation (p=0.15). Conclusion: A single drop of a combination of 0.8% Tropicamide and 5% Phenylephrine achieves adequate cycloplegia in patients between 11-40 years of age. Keywords: Cycloplegia, Troplicamide, Phenylephrine, Eye, Residual accommodation