Experts disagree on who needs it and when. Here’s what the evidence suggests. By Michelle Crouch Perhaps the most unpleasant part of an eye exam is when the doctor squeezes in the dreaded drops to ...

Many factors can influence pupil size. Typically, the pupils open up in low light situations to let in more light. However, some research suggests that attraction and mood might also cause pupil ...

When pupils are dilated, it means that they grow larger in size. This can happen for a number of different reasons, including drug use and arousal.

On the other hand, Dr. William Barlow of the University of Utah's Moran Eye Center notes, "Dilation isn't always required. In fact, if you are seeing your eye doctor solely to get a prescription, ...

If you have your pupils dilated for an eye exam, they may stay dilated for several hours. Your eye health provider dilates your pupils so they can get a clear view of the internal structures of your ...

Pupils are the black circles located in the center of your iris, or the colored part of your eye. The pupil allows light to enter your eye and often changes in size. When your pupils appear larger, ...

Amanda Meyer is affiliated with the Australian and New Zealand Association of Clinical Anatomists, the American Association for Anatomy, and the Global Neuroanatomy Network. Monika Zimanyi is ...