“Deep Heating” Noninvasive Skin Tightening Devices: Review of Effectiveness and Patient Satisfaction

Aesthetic improvement in the appearance of facial wrinkles, redundant facial, neck, or body laxity is a major feature of aging. Monopolar radiofrequency (RF) and ultrasound sources became a treatment of choice for non-ablative tissue tightening by volumetric tissue heating of the deep dermis.Non-ablative radiofrequency devices have gained popularity because of their ability to offer improvement of skin laxity without the postoperative recovery or financial burden of surgical procedures. It remains in demand secondary to its lower side effect profile and remarkably short post procedural downtime.This continuing shift away from ablative and invasive aesthetic procedures continues to be driven largely by patient and clinician preferences.¹ According to the American Society Aesthetic Plastic Surgery, 526,000 non-surgical skin tightening procedures (annual growth of 11%) were performed in 2016 in the United States.²The aim of this clinical paper is to review available literature for selected aesthetic devices utilizing deep tissue heating (Ultherapy, ThermaCool, Exilis Ultra 360). The data reported herein are based on a retrospective review of peer-reviewed clinical studies. Aforementioned devices are evaluated for safety and efficacy. In everyday practice, patient’s perceived improvement typically outweighs the practitioner’s scoring. Therefore, most of the clinical studies utilize subjective patient satisfaction scores.

Ultherapy (Ulthera, Merz North America, NC)The Ultherapy procedure is indicated for use in: lifting skin on the neck, on the eyebrow and under the chin The first aesthetic use of high intensity focused ultrasound (HIFU) was introduced in 2008 and it was FDA cleared for brow-lifting a year later. Currently, the microfocused ultrasound (MFU) is being used for non-invasive tissue remodeling.Currently available transducers emit frequencies of 10.0 MHz, 7.0 MHz, and 4.0 MHz with focal depths of 1.5 mm, 3.0 mm, and 4.5 mm, respectively. The higher energy transducers allow energy deposition in smaller anatomical regions. The ultrasound beam is focused to a point less than 1 mm³ in size below the skin surface (in the superficial muscular aponeurotic system) to form “thermal coagulation points”.³ Temperature inside of such points is increased to 65°C. Superficial layer of skin remains un-affected. This results in immediate collagen contraction and initiates collagen synthesis. The device incorporates automatic ultrasound imaging of the tissue for controlled energy delivery and acoustic coupling of the probe. The treatment zone is 25 mm and 14 mm in length, for the standard and the narrow transducers, respectively. Treatment is administered in a “stamping” manner.A prospective cohort study⁴ described results of facial treatment with the 4 MHz and 7 MHz transducers. At 90 days, 30 patients (86%) showed clinically significant brow-lift with a 1.7 mm mean elevation of the eyebrow. Fabi et al5 treated 70 patients on the neck. Quantitative assessment indicated that 72.9% of subjects achieved a visible tissue lift of > 20.0 mm² in the sub-mental area. Three months after, the improvement was still visible for 68.6% of patients treated in sub-mental and neck area, and for 67% of patients treated on face and neck.The long-term efficacy was studied also by Fabi et al.⁶ At 180 days, physician GAIS score revealed that 77.7% patients achieved improvement in the face and upper neck area, while