3 months post Cellulaze on backs of thighs and butt I have discoloration. How can I get rid of it?

CelluLaze can cause discoloration of the skin in several ways.  Bruising can cause hemosiderin (iron) deposits in the skin which stains it. Inflammation can also cause pigment deposition. Bleaching cream helps the hyperpigmentation. Time and light treatments. help the hemosiderin deposits. Best wishes.

Dark spots (post-inflammatory hyperpigmentation) may occur following Cellulaze treatment.  If the dark spots have not resolved after 6 months following treatment, Nd:Yag laser treatment may be used to target hemosiderin, the substance in the skin which causes the discoloration.  Nd:Yag laser treatment will initially result in temporary worsening/darkening of the pigmentation (which may last a few weeks to a few months depending on skin color), but will target the cause of the pigmentation and will result in lightening of the dark pigment.  

The discoloration is likely due to hypervascularity.   Rememeber it can take at least 3-6 months to see your final results and results continue to evolve and improve up to 12 months.  The theory is that the hypervascularity (increase blood flow to skin) is bringing new cells to build/thicken your collagen to improve the appearance of your skin - making it more resilient to show the effects of cellulite.  Hope this helps.