Please don't list this on a work's page as a trope. Examples can go on the work's YMMV tab.
Nightmare Fuel: The Howling
Pretty much all of them feature this in some way (though the third one is perhaps the most divisive). New Moon Rising features a lot of horrifying stuff as well... just not the stuff that the director actually intended to be horrific.
"I'm gonna give you a piece of my mind." Right before Eddie's transformation, he pulls part of his brain out through a bullet hole in his head.