Fabi Sabrina Guillen
Goldman, Butterwick, Fitzpatrick, Groff and Fabi, Cosmetic Laser Dermatology, San Diego, CA, USA.
Clin Cosmet Investig Dermatol. 2015 Feb 5;8:47-52. doi: 10.2147/CCID.S69118. eCollection 2015.
Microfocused ultrasound (MFU) has been recently developed to meet the ever-growing public demand for achieving significant, noninvasive skin lifting and tightening. MFU can be focused on subcutaneous tissue where the temperature briefly reaches greater than 60°C, producing small (<1 mm(3)) thermal coagulation points to a depth of up to 5 mm within the mid-to-deep reticular layer of the dermis and subdermis. The intervening papillary dermal and epidermal layers of skin remain unaffected. The application of heat at these discrete thermal coagulation points causes collagen fibers in the facial planes such as the superficial musculoaponeurotic system and platysma, as well as the deep reticular dermis, to become denatured, contracting and stimulating de novo collagen. A commercially available device combines MFU with high-resolution ultrasound imaging (MFU-V), which enables visualization of tissue planes to a depth of 8 mm and allows the user to see where the MFU energy will be applied (Ultherapy(®); Ulthera Inc., Mesa, AZ, USA). Using different transducers, MFU-V treatment can be customized to meet the unique physical characteristics of each patient by adjusting energy and focal depth of the emitted ultrasound. By targeting the facial superficial musculoaponeurotic system, noninvasive tightening and lifting of sagging facial and neck skin and improvements in the appearance of wrinkles can be achieved. MFU-V can also improve lines and wrinkles of the décolleté. Treatment protocols for the use of MFU-V continue to be refined, and its use in combination with other rejuvenation techniques has been demonstrated. Brief discomfort that often occurs during treatment can be minimized with oral nonsteroidal anti-inflammatory drugs. Other treatment-related adverse events include transient erythema, edema, and occasional bruising. MFU-V is best suited for patients with mild-to-moderate skin and soft tissue laxity. For older patients with severe skin laxity and marked platysmal banding, surgical treatment should be considered.
微聚焦超声（MFU）最近已被开发出来，以满足公众对实现显著的非侵入性皮肤提升和紧致不断增长的需求。MFU可以聚焦于皮下组织，使温度短暂达到60°C以上，在真皮和皮下组织的中深层网状层内产生小的（<1立方毫米）热凝固点，深度可达5毫米。中间的乳头真皮层和表皮层不受影响。在这些离散的热凝固点施加热量会使面部平面（如表浅肌肉腱膜系统和颈阔肌）以及深层网状真皮中的胶原纤维变性、收缩并刺激新的胶原蛋白生成。一种市售设备将MFU与高分辨率超声成像相结合（MFU-V），它能够可视化深度达8毫米的组织平面，并允许使用者看到MFU能量将被施加的位置（超声刀（®）；美国亚利桑那州梅萨市的Ulthera公司）。通过使用不同的换能器，MFU-V治疗可以通过调整发射超声的能量和聚焦深度进行定制，以满足每个患者独特的身体特征。通过针对面部表浅肌肉腱膜系统，可以实现对面部和颈部松弛皮肤的非侵入性紧致和提升，并改善皱纹外观。MFU-V还可以改善胸部的细纹和皱纹。MFU-V的使用治疗方案仍在不断完善，并且已证明它可与其他年轻化技术联合使用。治疗期间经常出现的短暂不适可以通过口服非甾体类抗炎药降至最低。其他与治疗相关的不良事件包括短暂性红斑、水肿和偶尔的瘀伤。MFU-V最适合轻度至中度皮肤和软组织松弛的患者。对于皮肤严重松弛且颈阔肌带明显的老年患者，应考虑手术治疗。
