Ultrasound assisted liposuction or UAL is a procedure in which ultrasonic energy is delivered to a patient’s subcutaneous fat cells in order to make them easier to remove using the traditional suction technique. This can be done internally or externally, with the internal method consisting of the delivery of ultrasonic energy directly to the fat cells by inserting a metal rod into an opening in the skin.
With external ultrasonic liposuction, a paddle is applied to the outside of the patient’s skin. The ultrasonic energy travels from the paddle through the skin and affects the fat cells directly under the area beneath the paddles.
Internal Ultrasound Assisted Liposuction - IUAL
First used in the early 1990s in Europe and Latin America, internal UAL proved imperfect during the first years of its use, as many complications were reported that caused harm to the patients.
The first and second generations of machines that were developed for this technique, some of which are still in use today, occasionally killed and burned tissue while in use. In addition, some patients had their kidneys or gallbladders punctured by the machines’ tubes, which are called cannulae. Because of these problems, the internal UAL technique was ultimately abandoned by most surgeons in Europe. However, it slowly caught on in the United States starting in 1996 because it was marketed as “cutting-edge”, and as a way to recapture some of the plastic surgery market that had been lost previously.
By 1999, a third generation of internal UAL machines was introduced in the United States. These machines were supposed to be much safer than previous incantations; however, this has not been proven. To date, the United States Food and Drug Administration has not yet approved the use of an internal ultrasound machine during liposuction.
External Ultrasound Assisted Liposuction - EUAL
External UAL is performed by passing a paddle, which emits ultrasonic waves, over the skin in an attempt to break up the fat cells before they are vacuumed out. The areas are first pumped full of fluid before the paddles are applied. It has been determined that in order for this technique to work, the ultrasonic energy has to be turned up so high in the paddles that it burns the skin, and if the energy is turned down to a safe level, it has no effect on the fat cells. Another problem that has been reported with this technique is a risk of a bad reaction to the gel or cream that is used to enable the paddle to slide over the skin. It is possible for the patient to have an allergic reaction to this lubricant, and there exists the possibility of the introduction of the gel or cream into the body through the incisions when the cannulae pass through. Because of these factors, external ultrasonic assisted liposuction is rarely used anymore.
Other problems that can occur during UAL include blood clots, seromas, and nerve damage. Because internal UAL produces heat inside the body, it often raises the temperature inside blood vessels to the point where blood clots develop. If enough clots develop in the body to where blood cannot reach an area, the tissue that is served by those blood vessels will then die due to a lack of oxygen. Also, an elevated percentage of patients who have undergone internal UAL have reported the loss of sensation in certain areas around where the procedure was performed, which would indicate damage to the nerves. Finally, UAL will typically cause a higher number of seromas than are caused by normal liposuction. Seromas are cavities beneath the skin that are filled with serum, which is a component of blood, and are formed when tissue is damaged.