For the past month or so I've noticed a flash of light when I open my eyes in the dark. It is crescent shaped and in the inside corner of my right eye. I had Lasik surgery about 8 years ago with great results but for the past year and a half my vision has been getting worse, I need glasses to drive and see at distances. I'm 41 so I know I should theoretically need reading glasses soon, but I have no problems with that. Is this flash something I should be concerned about?