Prep for anatomy scan?

When I was pregnant with my 2 year old, I was given fluid intake instructions to follow the day of the anatomy scan. It called for an absurd amount of water over a short period of time and they seemed to take it pretty seriously! I am still at the same hospital, and when I made the appointment, radiology just simply said for me to come with a full bladder. Is this the new normal? I'll call in the morning, just curious to see others' recent experiences.