What does gestational sac look like in miscarriage? Is it completely empty? It should at least have veins in it, right?

????????? An empty sac is just that, a sac without a fetus or fetal pole in it , all tissue can have veins, hat does not have anything to do with whether the sac is empty or not, once it is determined the pregnancy is non viable it should be removed either with meds or minor surgery or a combo of both.