Would a pelvic ultrasound show when a dermoid ovarian cyst has ruptured? what would it show?

Rupture is serious: Dermoids can have hair and teeth in them, so are complex on U/S,. The black stuff in the picture is hair. They often grow slowly but rarely rupture. If so, it's like appendicitis and needs immediate surgery. U/S is a good screen for ovarian masses, but with a "surgical pelvis" CT is done. An early sign of impending rupture on U/S might be fluid in the pelvis, but this is not diagnostic.