Wierd problem with Optio S50 screeen - Help !

I've got an odd problem with my Optio S50 screen. A couple of days ago, I noticed a few pixels in the screen had stopped working. There were a couple of black spots on the screen. The camera still works fine. The spots are firmly fixed relative to the sreeen, but uploaded photos just taken don't show ant problem when displayed on my PC. Today, when I switched it on, there were quite a few more failed pixels, but in a sort of wiggle - not a spot or straight line - almost as though something's munching it's way through the screen in a random sort of walk ! Anyone have any idea what it might be ? Is it stopable or repairable ?