Section 4 Plastic and Reconstructive Problems

Fiber Laser in Aging Face and Neck

Table 2 Management of thermal confinement and thermal diffusivity

LAFC may be addressed through a touch-up percutaneous LAFC procedure. LAFC treatment begins with identification and marking of the desired treatment areas. In keep- ing with anatomic studies of the jowl fat compart- ment, 6 the desired area of tissue ablation for contouring of the lower face and jawline may include subcutaneous tissue fullness at, below, and well above the caudal border of the mandible ( Fig. 1 A). In many patients, the position of the jowl changes substantially with supine or slight Trendelenburg positioning; therefore, patient marking for LAFC should be done with patients in an upright, seated position to most accurately ensure inclusion of the desired tissue in the out- lined treatment areas. The LAFC percutaneous entry point should be at least 1.5-cm posterior to the posterior extent of the intended LAFC treatment zone to ensure that an adequate tissue seal is maintained between the entry point and the treatment zone. If the entry point is placed too close to the LAFC treatment zone, the lipoas- piration step may be more difficult and inefficient because air may easily be drawn into the aspira- tion syringe. Ensuring that the desired tissue is treated dur- ing LAFC is accomplished via (1) minimizing any positional tissue shift with slight reverse Trende- lenburg patient positioning (eg, 20 ); (2) limiting exogenous water input with small amounts of local anesthetic used (eg, 3 mL); (3) using hyal- uronidase to improve local anesthetic distribution through the tissues; and (4) isolating and stabiliz- ing the target tissue between the user’s thumb

Mild to moderate post-treatment inflammatory edema (PIE) is expected. Early on, PIE seems to have blunted or limited the lower facial tissue con- touring response; however, lower facial contour improves over time as PIE gradually resolves and the skin contracts. Early on (eg, weeks 2 through 6), weekly lymphatic massage sessions for the LAFC treatment areas may help reduce PIE and improve lower facial contour. Significant PIE may be treated with staged escalating-dose intralesional triamcinolone (eg, 10 mg/mL initially, gradually moving to 40 mg/mL) beginning at post-treatment month 1 or 2 and continuing monthly as needed until final desired contour is achieved or until no further tissue response. Although this approach is successful in a majority of patients with PIE, the origin of persistent lower facial fullness with palpable subcutaneous fullness in partial responders is not known. Some of the adipocyte lipid content liberated during laser lipolysis may be subject to reuptake by adipocytes that remain at the periphery of the treatment area. A significant increase in body mass index after LAFC could also partially account for a blunted tissue response. It seems more likely, however, that the natural healing response to adipose tissue ischemia and adipocyte necrosis may stimulate a tissue regeneration response, with adipose tissue remodeling involving adjacent adipose-derived stem progenitor cells and forma- tion of neoadipocytes—this phenomenon has been carefully elucidated in animal models for adipose tissue ischemia 4 and nonvascularized fat grafting. 5 Persistent fullness 6 to 12 months after