What is a Granuloma and What Causes It?

A granuloma is a mass or nodule (a lump or bump) usually associated with an infectious (bacterial or fungal for example) process that produces inflamation (swelling, redness and pain). A granuloma may resmble a foreign body reaction as with a splinter or, more to the point, from an injection of a substance, such as with dermal fillers used for cosmetic purposes to improve facial lines and enhance contour.
True granulomas with any filler are quite rare. More commonly, too much material can settle in one small area causing a bump that is palpable (can be felt) and may be visible. This is common and can often be improved with massage, but extraction of the excess may be indicated and occasionally a needle can be utilized to simply remove the excess (especially with hyaluronic acid products such as Restylane and Juvederm).

Granulomas form in response to a foreign body. Our body has various defense mechanisms and if it encounters something it doesn't like, it will try to surround it and block it from being exposed. In other words build a wall of protection around it so it doesn't irritate our body any more. When that protective wall is formed, it's made from inflammatory cells and they create this ball like structure, called granuloma. Tiny ball or nodule you feel when you press n the skin.   Dermal fillers made from Hyaluronic acid are very safe and have been used for over 20 years and the chance of them causing granulomas is extremely rare but not completely impossible. Even if they did cause them, they can be immediately treated in the hands of a professional and skilled physician. Hope this helps, Dr. Avaliani

Thanks for your question -
A granuloma is your body's immune response to a foreign body. There are substances that are more likely to cause granuloma formation and substances that are less likely to form granulomas.
Most modern injectables (especially the HA injectables) typically do not form granulomas as they are minimally stimulating to your immune system. It is not impossible though.
Discuss the lumps with your injector. They will likely recommend observation and time.
The lumps will likely resolve.
I hope this helps.