Frankly, this is something which many doctors debate about. Some insist that there is significant volume loss of fillers after Ultherapy, while some deny such an occurrence.
There have been figures thrown around like 10-15% reduction (IF it happens) of filler volume post Ultherapy.
In my practice however I prefer to take the safe route and do HIFU first and then about 1-2 weeks later to follow up with the filler placement (if indicated). Why take the risk?
Winston