Treatment options for skin laxity have expanded rapidly, including HIFU, RF, and RF Needling. However, as devices diversify, physicians often struggle to determine which treatments to use, in what order, and at what intervals to achieve optimal results. Our clinic also have multiple devices, including HIFU, Thermage, and Titan. However, introducing every new device is impractical; the key to achieving maximum effectiveness lies in how existing devices are combined. This article introduces the combined protocol of ULTRAcel [Zi:] (HIFU) and DENSITY (RF), frequently used at our clinic, along with its clinical results.
- INDEX
The Evolution of HIFU and Features of ULTRAcel [Zi:] (02:15-)
HIFU has evolved through three major generations. The first generation featured basic SMAS heating via focused irradiation. The second generation saw the development of linear tips. While dot-type focuses on lifting, linear-type heats the fat layer linearly at lower temperatures, making it suitable for contouring. The third generation [Zi:] enables switching between dot and linear modes and depth adjustment within a single cartridge, while also improving irradiation speed. Furthermore, the adoption of a foot switch reduces the risk of tendonitis, representing a breakthrough for busy clinics handling numerous cases. At our clinic, we primarily use from 1.5 to 6.0mm (especially 1.5/2.0/3.0/4.5mm for facial applications).
DENSITY Technology and RF Advantages (04:33-)
DENSITY is an RF device featuring both monopolar and bipolar modes, backed by evidence of increased collagen fiber density. The High Tip enables simultaneous monopolar and bipolar irradiation, while the Classic Tip uses monopolar mode only. Its five-level cooling system using cooling gas, combined with impedance measurement per shot to optimize energy delivery, represents a key advantage not found in Therma cool. The tips have no usage time limit, allowing economical use across multiple patients. The only drawback is the approximately 10-minute startup and gas exchange times, but these can be easily managed with operational planning.
Our clinic’s protocol: RF first, then HIFU (06:56-)
At our clinic, we first irradiate 300 shots of DENSITY at 2.0–3.0 J (cheeks: 2.5–3.0 J, submental area: 2.0–2.5 J). Following this, we apply ULTRAcel [Zi:] at 4.5mm → 3.0mm → 1.5mm, delivering 100–150 shots at each depth. If needed, we add 2.0mm shots to areas like the lower eyelids and brow area. We apply RF first because the RF-specific gel differs from the HIFU gel, allowing us to achieve both treatment efficiency and hygiene. Recommended intervals are 6 months for DENSITY and 3 months for [Zi:]. Treatment time is approximately 10-15 minutes for [Zi:] and 15-20 minutes for DENSITY. Pain and downtime are mild, with redness typically subsiding within half a day.
Case Studies, Efficacy, and Future Prospects (07:12–)
HIFU alone typically shows results after 2 to 3 weeks, but when combined with DENSITY, many patients notice tightening of the jawline and labiomandibular fold immediately after treatment, with effects often lasting over a month. Notably, even patients who previously felt they needed another HIFU treatment within three months report a significantly different level of persistence after this combined therapy. The greatest advantage is achieving both immediate results and lasting effects. A future challenge involves developing new protocols combining the Advanced Tip and High Tip while maintaining safety and efficiency.
