Facial hematoma from a muscular injection. Diagnosed w/fat necrosis. Can facial fat transfer work w/scar tissue present? (Photo)

I think fat transfer would work well for you. Not only will it fill the defect, but it will likely improve the scar tissue and rejuvenate the overlying skin. Please see attached video for details of the procedure.

I would recommend using fillers first. Facial fat transfer is good for diffuse and precise small areas but does not do well in small areas or more volume is needed.  Overd grafting leads to a higher percentage of graft loss. If fillers can regain a normal contour then facial fat transfer could do the same. If fillers failed to restore the contour then scar tissue is pulling the skin down and this may be more difficult to correct. With fat transfer you may need and do better having more than one procedure.  Fillers are in general more predictable and forgiving.  Best, Mats Hagstrom M.D. 

you have a hollow on the face. You want it filled. I have been doing fat for almost 30 years, but I think the quickest cheapest and most reliable thing to do would be to use fillers. You should be able to get 11/2 years out of an HA filler at which point the underlying problem may have improved.