Seeing dark ring at bright places

[aixxia]

Hi, my mum has been seeing a dark ring when looking out at bright places, the ring will be gone when she close her eyes and when she's at dark area. This has been going on for a week. May I know what causes this problem and how can it be help? Is this dangerous? Thanks a million.

[Ray T Oyakawa, MD]

There many causes, some serious.  Please see an EyeMD, an ophthalmologist.

Dr. O.