Liposuction is a procedure where excess fat is removed from under the skin. There is a superficial fat layer and a deep fat layer. The superficial layer is what makes the skin look smooth. We generally leave that layer intact. If you look at the back of the hand you will notice that it's easy to see the veins and tendons because there is almost no fat present. If you pinch that skin and compare with say the arm you will notice how thin the hand skin is. When we do liposuction we try to take mostly the deep fat layer.
Once the fat is removed it does not come back. We are all born with a genetically determined fixed number of fat cells. When we consume more calories than we burn, the excess calories are stored in these fat cells. The cells fill up and expand when we gain weight and they shrink when we lose weight. We do not make any new fat cells. That explains why some people can gain up to 500 lbs and some people can't....not enough fat cells to store all that weight. Once the fat is gone there are no cells to store fat where it was removed from BUT excess fat can be stored elsewhere, where fat was not removed...thighs, buttocks, arms, breast....anywhere there is a larger complement of fat cells. Remember, not all the fat is removed during liposuction. A small layer is always left behind to help the skin look smooth and not wrinkled. That small amount left behind can grow if you gain weight but usually not significantly.
Liposuction removes the fat only. It leaves the skin and the muscle intact. When the fat is gone the skin will generally shrink. It may shrink a little or a lot depending on several factors. Age, skin elasticity, genetics, number of pregnancies etc. One of the things we do during the physical exam is to determine if the skin has a good chance of shrinking after the fat is removed. If yes then liposuction will work. If no, then perhaps that patient needs a tummy tuck to remove the excess skin along with the fat. In liposuction the fat is removed through small holes about the size of the tip of a pen. There is no cut or long incision.
There are several types of liposuction. They all have four steps. Three steps are for the most part the similar in all the liposuctions, one step is different in each one (step 2).
Manual. The old school way, youtube videos of back and forth thrusting to physically break up the fat come to mind. Lots of swelling and bruising. Rarely done these days.
Ultrasound: A machine uses ultrasound waves to break up the fat. Less bruising. Produces heat so still has significant swelling. Can burn the skin. Great for dense fat like upper back. Can produce seromas (Fluid collections) and skin rippling.
Power assisted (PAL): The machine vibrates and oscillates to break up the fat. No heat generation and thus no skin burns. Less swelling and bruising. MICROAIRE is the most popular manufacturer. This is the machine I use most of the time.
LASER: This machine uses a beam of light to break up the fat. No heat so no burns. Minimal force so minimal swelling and bruising. Breaks up difficult fat well like upper back. THE ONLY ONE THAT HELPS THE SKIN TO SHRINK by stimulating collagen formation in the overlying skin. Because the fat cells are destroyed it cannot be used for fat transfer to the buttocks or breast.
During the examination we check to see if there is excess fat in the areas the patient wants the fat to be removed from, or is it just excess skin? Is it deep fat or superficial fat? What is the quality of the skin? Is the skin thick enough so that when the fat is removed the skin will heal nice and smooth? Is there excess skin that will hang loosely if the fat is removed and look worse? Are there any hernias which may have bowel or other organs at risk in the fat? Does the muscle need to be tightened? Is the patient a good candidate? Pictures follow after surgery.