History

Traditional suction-assisted lipoplasty (SAL) became popular in the United States in the 1980s. Although initially met with scepticism, it was eventually embraced and quickly became the gold standard tool for liposuction. The introduction of the tumescent technique by Jeffrey Klein further increased the safety and efficacy of the procedure by reducing fluid and electrolyte shifts, thereby allowing larger volumes of fat removal with considerably less blood loss. The concept of applying ultrasonic energy to adipose tissue was first conceived by Zocchi of Italy in the late 1980s. Ultrasound-assisted lipoplasty (UAL) involves the application of ultrasonic energy to adipose tissue, which effectively “liquefies” the fat by cellular fragmentation, causing release of cellular contents into the intercellular space. A combination of triglycerides, normal interstitial fluid, and the infused tumescent fluid forms a stable fatty emulsion, which can be extracted from the subcutaneous space by low-vacuum suction. The specificity of the ultrasonic sound waves for low density tissues such as fat allows selective targeting of fat cells with minimal effect on intervening connective tissue and neurovascular structures. Ultrasonic medical devices have been used in a variety of other medical fields (neurosurgery, general surgery, ophthalmology, and urology) and proven to be extremely useful and safe. A variety of UAL surgical devices are available on the market today and it is beyond the scope of this chapter to discuss the differences in the various machines.

We have used a variety of ultrasonic generators as the technology has developed over the years. Our early experience was with the first generation devices which delivered continuous wave ultrasound via a solid, blunt-tip probe which effectively fragmented fat before evacuation. Second-generation UAL machines used 5-mm diameter hollow cannulas that would allow for simultaneous fat fragmentation and aspiration. Reported complications with second generation ultrasound lipoplasty devices were thought to be related to the amount and duration of energy applied to the adipose tissue. Third generation devices were therefore developed with “pulsed” delivery of ultrasonic vibration to allow increased control of the ultrasonic energy.

Physical evaluation

A liposuction consultation should begin by asking the patient, what would they like to change about their body?

Anatomy

One of the most important factors to consider when evaluating a patient’s candidacy for liposuction is their patient’s skin tone, or dermal quality. It is important to pinch and palpate the skin, assessing for the degree of laxity and dermal thickness (Fig. 65.1). Young thick undamaged dermis is more likely to retract after liposuction and give a desirable result. Thin, stretched skin with striae is unlikely to retract and may look worse after liposuction. If it is determined that the skin quality is not suitable for liposuction, alternative procedures, such as skin excision, may be indicated. Liposuction does not improve cellulite, thus one should not make promises to this effect.

Fig. 65.1 A patient with a protuberant abdomen with paucity of subcutaneous fat. A, The patient’s protuberance is due to muscle laxity and poor posture. B, When the patient is asked to “pull in” the muscles, protuberance lessens. C, Pinch thickness is minimal.

The quality of the fat should also be assessed because it may also affect the outcome. Generally speaking, firm, fibrous fat is more “forgiving” than soft, loose fat. The softer fat has large lobules with wispy intervening fibroconnective tissue. This type of fat is removed readily and is easy to over-resect; as a general rule, the overlying skin is thin. The fibrous type of fat tends to be densely packed between tightly woven intervening fibroconnective tissue. This type of fat is less readily removed. The overlying skin tends to be thicker and can be expected to retract well. The better retraction is theoretically due to the retractile properties in the fibroconnective tissue and in the dermis itself.

The anatomy of the subcutaneous adipose tissue varies through the body. Some areas of the body have both a deep adipose compartment and a superficial adipose compartment, which are separated by the discrete subcutaneous fascia. The superficial fat in the trunk and thigh consists of smaller lobules, tightly organized within the vertically oriented thin, fibrous septa and the zones of adherence differ between males and females (Fig. 65.2). The deep fat consists of larger lobules arranged more loosely within deeply spaced and more irregularity arranged septa. In these areas, the deep layer of fat is the target for liposuction. The overlying superficial fat is relatively thin and will act as a protective layer to hide small contour deformities, especially for the in experienced liposuction surgeon. In contrast, other areas of the body that are commonly suctioned (arms, lower legs) have only one layer of fat. Suctioning these areas with smaller cannulas will help to avoid contour irregularities.

Fig. 65.2 Diagram of superficial fascial system anatomic variations in men (left) and women (right). The superficial fascial system zone of adherence is at the iliac crest in men and several centimeters inferior to the iliac crest in women.

From Lockwood T. Superficial fascial system (SFS) of the trunk and extremities: a new concept. Plast Reconstr Surg 1991;87:1011.

Technical steps

Marking and positioning markings provide a necessary “topographic map” that allows the surgeon to visualize the targeted convexities, to avoid concavities, and to address asymmetries when the patient is lying on the operating table. Markings should be done immediately before surgery with the patient in a standing position (Fig. 65.3). A permanent marking pen is recommended so the markings will not wash off when the patient is prepared. Asymmetries should be carefully marked and brought to the attention of the patient. Depressions and indentations are marked with a different color marker so these areas can be avoided or fat grafts can be planned.

Fig. 65.3 Schematic of markings. A, Anterior view. B, Lateral view. C, Posterior view.