PP it takes long enough to get through on the phone at the best of times, without hanging on to ask, thats why I am hoping the knowledgeable ab folks may know
i had an ultrasound two weeks ago, adsomen and pelvic exam, they didn't tell me not to eat, just to drink plenty of water before the abdom exam so i had a full bladder. i'd had lunch maybe 2/3 hours beforehand
The reason for fasting is to ensure there is no food or fluid covering the area that is to be examined, and to reduce bowel gas - ultrasound cannot penetrate this.
Fasting also allows the gall bladder to be seen, as it contracts after eating and may not be seen if the stomach is full.