He's going through a bad/difficult/rough 'patch' [='spell'] right now.
The chair's original paint is still visible 'in patches'. [=in spots]
The doctor 'patched' him 'up', so he's going to be as good as new.
(..) I saw you do it. - Okay, then why the hell are you calling me? - Because you need to fix it. You need to patch it up, upgrade it, Whatever it is you do. How exactly? - You go back into his mind and erase his memory again. (..)2009 TvShow: Heroes Title: Chapter One 'Orientation/Jump, Push, Fall' Season: 4 Episode 1