Hydrogel Butt Injections are not approved by the FDA. Due to the fact that Hydrogel is a foreign material, it carries a higher risk of infection than fat transfer in a Brazilian Butt Lift, both at the time of the procedure and even several years after the procedure has been performed. Although it is possible to preform a BBL following Hydrogel injections, a repeat procedure in this same arae would carry a higher risk of infection which may be difficult to treat and could result in significant complications and scarring. I would think carefully about these risks before proceeding with further surgery. Consult with a board certified plastic surgeon, who has extensive experience in the BBL procedure. Best wishes.