The Effect of Brimonidine on Intraocular Pressure When Dilating Routine Patients

Twenty healthy participants will be separated into two groups of 10 volunteers each. In both groups, the participant's right eye will serve as a control with only Tropicamide/phenylephrine given. In one group of 10 participants the left eyes will receive Alphagan prior to Tropicamide/phenylephrine. In the other group of 10 eyes, the left eyes will have Tropicamide/phenylephrine administered prior to Alphagan. The investigator will observe the intraocular benefits of the addition of Alphagan over the Tropicamide/phenylephrine alone and determine if pre-treating is any better than post-treating. In addition, the investigator will monitor pupil response, as it is known that Alphagan may have some effect on the pupil dilation.