Is it possible to inject HA filler directly into the facial fat pads in order to re-inflate them?

Yes, appropriately placed fillers can look natural and prevent aging and decent of fat pads etc.  I would suggest finding someone experienced, specifically in treating younger patients and doing "age prevention" treatments that look natural.  Best, Dr. Emer.

Hi Brunette. Without seeing at least a picture it is very difficult to determine what your needs are and which treatment would be best for you. I would recommend an in-person consultation with an experienced physician injector in your area who can make a personalized assessment based on your needs. Best of luck.

Yes, HA's can be used to fill the cheek fat pads.  There are several different kinds that can be used. Best to seek an evaluation in person.

Absolutely. HA fillers in the facial fat pads are the key re-flating the face in a natural way. Any HA filler is fine, although the thicker HAs are ideal (Voluma, Perlane).

My filler of choice for re inflation of facial (malar) pads  is fat injections combined with PRP (platelet rich plasma)

Voluma has been available in the US for about a year now. It is an HA filler specifically made to volumize cheeks. the best thing for you to do is go for a consult and see if you are a candidate for this treatment and if not what your other options are.

Facial contours can be enhanced by use of fillers or fat.  They are usually put under the fat pad directly on the bone to elevate it but can be placed within the soft tissue. They can reelevate deflated areas or, in people like you, accentuate congenitally underfilled areas. The most common fillers used for this are Juvederm Voluma, a hyaluronic acid, and Radiesse, a calcium hydroxyapitite.