Comparing the mydriatic effect of tropicamide with respect to iris pigmentation.

It has been believed over the years that mydriatics have had lesser effect on darker pigmented irides. In this study pupillary diameter was measured under 70 foot-candles of illumination before and after 1% tropicamide was instilled for a duration period of 30 minutes. It was concluded that, (a) 1% tropicamide did dilate the pupil, (b) light irides were significantly larger than dark irides before dilation, (c) no significant difference in the change of pupil size between light and dark irides was evidenced.