Liposuction. Image 8 of 11. Surgeon using a cannula (tube) to remove fat from a patient's buttock during a liposuction operation. This cosmetic surgery procedure removes unwanted fat from areas such as the hips, upper thighs and buttocks. Markings drawn on the skin act as guidelines for the cosmetic surgeon. A small incision is made, near the area to be treated, into which the cannula is inserted. The cannula is used to break up fatty deposits, which are then sucked out down the plastic tube by a powerful vacuum. For a sequence showing a liposuction procedure, see images M590/260 to M590/270.