Hairbrush? If you haven't seen it, the line won't make any sense.
I am almost convinced that the last several episodes have been a dream sequence. I'll bet ten bucks that they resolve everything next season by saying that Cuddy actually died of cancer (since Lisa Edelstein isn't coming back next year), and that House has been hallucinating all along. It would be lame, but I'll bet they do it. It would explain many of the inconsistencies in last night's episode.