There are a variety of different ways. Sometimes it is very difficult to tell reliably and the only way to know for sure is the surgical procedure itself.
The difference is actually of concern only to the surgeon anyhow as everything from our point of view is essentially the same.
The same emotional impact etc.
In most cases, there are both glandular and fatty tissue rather than one and not the other.
Knowing these things; I think it would be unwise to commit the surgeon, in advance, to a particular method or procedure. Far better would be to leave the methods employed up to the conditions found as the surgery proceeds.