**3. Technique**

A good medical history should be taken as part of preventing complications including contour deformities. A well-informed patient who understands every step of the process suffers less anxiety and tolerates mild discomfort more easily. Discomfort limits access to deeper fat compartments makes fibrous areas harder to treat and often leads to a partial treatment or hurried treatment.

There are no formalized standards for preoperative assessment. However, there is consensus in the literature. Araco et al. exclude patients with a body mass index (BMI) > 30, patients with "severe" cardiovascular or pulmonary disease and patients with altered liver function, platelet function or vascular instability (Raynaud's) [11]. In a review, Wells and Hurvitz restricted patients to anesthesia classes 1 or 2 [12]. Smokers should be advised that they may have poor wound healing. Patients with diabetes should be advised of an increased risk for infection as well as delayed wound healing. A hemoglobin A1C of 6.5 or less indicates a decreased risk of adverse events. Skin laxity post-liposuction may not tighten as well in smokers, diabetics or post-menopausal women [13].

A thorough physical examination should be performed. Surgical scars in the treatment area, abdominal herniations, areas of contour deformity and the grade of skin laxity should be noted. After liposuction, previous surgical scars that are not released (e.g. caesarian section, appendectomy) may act as shelves and dramatically change the overall contour. Similarly, severe skin laxity will not significantly correct and will remain a deformity. Likewise, excessive fat removal may leave lax skin that was not obvious before the volume was removed. Unfortunately, it is difficult to predict how a patient's skin will tighten. Several factors play a role, including environment and genetics. Premenopausal women and women on estrogen supplementation may have the best improvement in post-liposuction laxity. This may be because estrogen directly increases fibroblast activity and contributes to collagen and elastin synthesis [14].

The patient's expectations are of course just as important as our own. Excellent communication must exist between the provider and patient at every step. The patient must be well versed in the entire procedure they have elected to undergo. Realistic expectations are very important, as the patient may have an idealized image of themselves post-liposuction that exceeds the parameters of the treatment or may even necessitate a more advanced procedure (abdominoplasty). Photographs that depict realistic results should be reviewed.

After consent, photographs should be taken of the patient in a normal anatomic position. Afterwards, using either a mirror or photographs, the provider should personally discuss with the patient the areas to be treated and give a detailed expectation of results. Proper consideration should be given to the body site being treated. The body should be placed in an anatomic position when considering your approach and mapping. Tensing of musculature may reveal adhesions, herniations, diastasis or asymmetries not otherwise evident. Cellulite, scars, skin textural differences and asymmetry should be carefully noted.

Contour markings should be drawn topographically using a permanent marker and photographs retaken. Care should be taken to mark areas to avoid or that need excess caution (subcostal margin, iliac crest, gluteal crease). Some providers also mark areas where more extensive liposuction might be desired, such as the border of the rectus abdominus. Asymmetry should be noted. Scars and previous surgical sites should be demarcated.

The safe tumescent technique is discussed elsewhere. During tumescence, pretunneling is beneficial. Passing the infusion cannula through deep and superficial fat layers distributes tumescence more uniformly, preventing "hot spots" of patient discomfort. Using a fanning pattern prepares the tissue for larger cannulas during suction and helps with uniformity. Once liposuction begins, gradually larger bore cannulas can be used, starting with smaller cannulas. Fanning patterns should overlap in minimally two areas and preferably three. The use of gradually larger bored microcannulas is unique to in-office tumescent liposuction. Patients experience more pain when larger cannulas are used immediately, effecting the physician's ability to take their time uniformly suctioning the treatment area. This will result in poor liposuction techniques and possibly significant contour irregularities. This is especially true around the umbilicus, where fat compartments are isolated from the rest of the abdomen and anesthesia is harder to obtain if tumescence is insufficient. This may lead to under-correction around the umbilicus (**Figure 1**). Larger bore cannulas can be used under general anesthesia by an experienced physician. However, they run the risk of contour deformity because large volumes are removed with each pass. Microcannulas pass easily through septae even in superficial layers and allow a "fine tuning" approach without causing irregularities of the skin surface. They also cause less trauma to fibrous bands connecting the skin to the deeper fascia layers, allowing the skin to remain in its normal position during the natural skin tightening that occurs over the following months. Large bore cannulas should be restricted to use by experienced providers who are very adept with tumescence and volume management. Microcannulas also decrease the risk of bleeding and hematoma formation. An 8 mm cannula transects fewer vascular components than a 2 mm cannula. Similarly, the probability of leaving a large potential space is decreased using the microcannula technique thus decreasing the risk of seroma.

Fat should be suctioned sequentially first from deeper layers then superficial layers. If the original layer suctioned is too superficial, there is a tendency on behalf of new practitioners to assume the tissue, they are grasping is the only area that needs treatment and deeper layers of fat are overlooked. Power-assisted liposuction and laser-assisted liposuction are also rapid and may increase contour irregularities. In an analysis of 2398 patients, contour deformities occurred at a rate of 5.9% when only power-assisted liposuction was used [15].

**Figure 1.** *Periumbilical under-correction.*
