**15. Micro needling RF**

Another RF based technology enhancing liposuction results is micro needling RF. The fractional coagulation of subcutaneous tissue helps tight the skin and reduce skin sagginess after liposuction [34].

Fractional skin treatment was introduced in esthetic medicine about two decades ago and has become one of the most popular modalities for the improvement of skin quality. This procedure is based on the coagulation of multiple small spots with a size of 100 microns to 0.5 millimeter. This allows the procedure to be very tolerable and with relatively short down-time. Focused laser beams or needle sized RF electrodes are used for ablation of micro-spots resulting in high efficiency and consistency of the treatment, with low risk of side effects and fast skin healing.

In contrast to lasers where the thermal effect is limited by the ablation crater, the RF energy flows through the whole dermis, adding volumetric heating to fractional treatment. This volumetric bulk heating adds a skin tightening effect to the more superficial improvement generated by tissue ablation.

RF fractional technologies are differentiated by needle length and size. The flat electrodes provide a more superficial effect improving texture and fine lines [34, 35] while longer needles penetrate deeper, providing deeper dermis remodeling and causing substantial skin tightening [36].

The needles can penetrate to the different depths allowing epidermal ablation and deep subdermal treatment. Recently the FDA cleared Morpheus8 device of InMode Ltd. for treatment up to depth of 7 mm.

**Figure 22** shows Morpheus8 tip schematically with needles extended to the subdermal fat.

Needles coated with polymer and releasing RF energy only at the needle end provide better protection of epidermis and provide lower down time.

A microscope image of a coated needle is shown in **Figure 23**. The gold plated needle has diameter of 0.3 mm and coated with polymer of 20 microns thickness.

There are several different configurations of RF electrodes for micro-needling devices. The most common configuration is by applying RF energy between adjacent rows of needle electrodes. This method creates a coagulation zone in vicinity of the needle end.

**Figure 23.** *Coated needle.*

The alternative technology is used in the InMode Morpheus8 device where RF energy is applied between the needle and an external electrode applied to the skin surface. Each needle has a strong thermal effect near the needle end and gradient of bulk heating toward the external electrode, similar to RFAL technology. Each needle generates small bulk heating but superposition of the heat from multiple needles results in essential thermal effect. Morpheus8 device automatically treats tissue in multiple layers delivering RF energy sequentially during needle retraction. This burst mode creates three-dimensional matrix of coagulation zones and strong bulk heating. Schematically the burst mode treatment is shown in **Figure 24**.

Micro needling technology was developed for treatment of facial wrinkles but further development of the technology has extended its use to treat the body as well.

The micro needling technology supplements both regular liposuction and energy-based minimally invasive technologies and addresses the first few millimeters of body coagulating adipose tissue and tightening FSN.

**Figure 24.** *Schematic illustration of burst mode treatment using Morpheus8 device.*
