Alma Lasers's Accent is a 200-W, 40.68-MHz, high-frequency radiofrequency (RF) generator. Accent is designed for contact operation using a unipolar probe and a bipolar probe for volumetric and surface heating, respectively.

The unipolar treatment tip handpiece (antenna) creates an electromagnetic field deep within the dermal tissue, which changes polarity 40 million times per second. That polarity change generates heat based on water molecules' movement and their friction between themselves and other tissues.

The unipolar probe delivers the RF energy to tissue from the ball-like extremity of the coupling tip. Delivery of RF energy is to the deep dermis and beyond.

The bipolar probe is designed for surface heating from 2–6 mm in depth, depending on tissue properties. There is a coaxial-grounded electrode that surrounds an RF tip.

The initial effect of treatment is twofold: an immediate three-dimensional collagen contraction (horizontal and vertical fibers), producing a dermal contraction for tightening, and a fibrous septae contraction for contouring. The tissue heating during treatment also produces a secondary wound-healing response, with further collagen deposition and remodeling, resulting in additional tightening over time.

As of the date of this publication, Accent is approved by the Food and Drug Administration for skin tightening and wrinkle reduction in the face and body. Off-label and experimental studies have documented its efficacy for cellulite reduction, collagen deposition, contraction of the fat in the abdomen and arms, and reduction of arm and abdominal circumference (Figure 56.1).