Normal pupil:

The pupils of an individual are usually very symmetrical in appearance. In certain instances the pupils may vary in size. Occasionally, differing pupil size is inherited and there is no underlying disorder. Varying pupil size may also be due to infection, tumors, disease or trauma.
- Reviewed last on: 6/24/2009
- David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; Daniel B. Hoch, PhD, MD, Assistant Professor of Neurology, Harvard Medical School, Department of Neurology, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.