2 vertical lines at top left of screen on high detail

[J unit Jedi Master]

after dying in the game on High detail, 2 vertical lines appeared at the top left of the screen that don't go away (even tried reinstalling). moving issac over to the line would cover isaac with the line, he doesnt cover it up. changing the detail to medium gets rid of the lines, or changing the resolution down to 800x600, or running in "small" window. I have played this game many many times, and have never seen this before, and it doesnt go away no matter what I try. could dying in a funky way cause this? Is it fixable?

[Reyn]

The two lines showed up after I installed the dlc, they weren't there before...

[J unit Jedi Master]

odd, at least there is a lead to fixing the problem now thanks to you