Is it an infection or a reaction to the local anesthetic?
If the discoloration is not just limited to the area treated by VASER, then it may be a systemic reaction to a medication; however, if it is limited then it is likely due to the heat generated by the VASER probe especially if it was left on high continuous setting for a long duration too close under the skin. If you have a sensitive skin or history of dermatographism, your skin will likely react to any trauma. You may also have had a localized reaction to the content of the anesthetic solution used in wet or tumescent liposuction techniques common with VASER liposelection. You will need to stay in touch with your surgeon and possibly start on anti-inflammatory medications or topical hydroquinone to help fade the discoloration.