What causes off centered pupils?

The pupils in my eyes are not centered like most people. In the colored part, they are slightly higher than center and closer to my nose. I had an eye doctor tell me she wanted to take a picture because she had heard of but never seen my "disorder". However, she could not remember the name. Does anyone know the name of my abnormal pupils and what causes them? Does anyone else out there have the same abnormality? I have been this way all my life and am unaware of any vision problems compared to "normal people". As I get older though, and my vision gets worse, I wonder if there is something I should become more educated about.