Sometimes I've noticed that there are cosmetic threads left on a view which don't exist anymore also on the odd occasion even lines. I think this could be because in the past in the specific view lines/thread might have been hidden to enhance visability on the view.

I have only notticed this problem in a assembly drawing.

Is there anyway to total refresh these problem views so the cosmetic threads/lines which don't exist anymore disapear?? Ive tried rebuild and model items feature, perhaps there is something really basic I'm missing??