11 VASER Technology for Body Contouring

Alfredo Hoyos and Mauricio Perez

Abstract

Ultrasound technologies were introduced to liposuction in the late 80s to selectively emulsificate the adipose tissue and facilitate the fat extraction. Three generations of devices has been developed reducing the amount of required energy while maintaining the emulsification efficacy. It works by creating a vibration frequency close to the fat specific resonance which disrupts the fat cells while safely avoid the surrounding tissues. The use of different type of probes and energy intensity allows to treat different conditions and types of patients. The ultrasound also effects on the dermis by inducing retraction and reducing the amount of blood loss. The harvested fat has been successfully used for grafting due to the adequate viability.

The use of this technology requires an adequate training and safety protocol to achieve the desired results and avoid complications.

Ultrasound – VASER – emulsification – resonance – high definition

11 VASER Technology for Body Contouring

Key Points

Surgical specialties have always been susceptible of multiple technological innovations, since improvements in techniques and results are almost always associated with new devices or gadgets. Body contour surgery is one of a kind in this matter, as many devices do exist as techniques for liposuction. One of the best devices for this purpose is vibration amplification of sound energy at resonance(VASER), which is crucial to perform high definition lipoplasty.
VASER uses ultrasound energy to emulsify adipose tissue and improves fat removal without vascular or cell injury.
Two different modes (continuous and pulsed) are employed depending on the zone to treat and the type of procedure you would like to perform.
Ancillary procedures can be used in addition to VASER-assisted lipoplasty depending on the surgeon’s preferences and type of surgery.
Different probes and cannulas have been designed to help the surgeon perform a safer procedure with less morbidity and better results.
VASER-assisted body contour surgery has been widely performed with low morbidity and low rate of complications.

11.1 Introduction

11.1.1 Ultrasonic Technology in Medicine, History, Uses, and Refinements

New technologies and devices have positively impacted the outcomes and the way liposuction is performed. Ultrasound is a powerful tool both for diagnosis and treatment in many medical conditions. Studied since 1930s for therapeutic and diagnostic usage, the first applications were applied for the heating capacity to produce a biological effect. The devices rapidly improve in such a way that it was even able to be successfully used for vestibular nerve destruction in Meniere’s disease and even brain tissue ablation in Parkinson’s disease. Kelman introduced phaco emulsification for cataracts in 1967 after being inspired by his dentist’s ultrasound device for descaling. Also, neurosurgeons started using it for selective destruction of tumors, and general surgeons for cutting and coagulating tissues during laparoscopic surgery. In the late 1980s and early 1990s, Scuderi and Zocchi pioneered the application of ultrasound for selective emulsification and removal of fat for body contouring. Ultrasound devices have been upgraded by 3 generations and nowadays we regard the latest technology with specific targeted tissues depending on the device physics and specifications. In 2001, Sound Surgical Technologies introduced a third-generation device, designed to improve safety by reducing the power delivered to the tissues whilst maintaining efficacy. This new technology was patented by the name VASER that became swiftly the gold standard for high-definition body sculpting surgery.

By including VASER to body contour liposculpture, tissues were highly protected from burns, intraoperative and postoperative bleeding decreased, and stem-cell harvesting was possible from the extracted adipose tissue, with the aim to be grafted later in surgery in some areas with lack of volume or projection. Different studies have been published supporting the use of ultrasound in cosmetic surgery and VASER is not the exception. However, it has been proposed for many other uses including dental cleansing, physiotherapy and so forth. Currently, the FDA has approved ultrasound therapy for cancer, gynecologic ablations, glaucoma, laparoscopic surgery, kidney stone comminution, plantar fasciitis, phaco-emulsification, thrombus dissolution, transdermal drug delivery, bone fracture healing, and lately for skin tightening and adipose tissue removal. All these indications has some evidence to consider them useful and safe for human use (▶Fig. 11.1).

**Fig. 11.1** VASER system: ultrasonic electric generator **(a)** and handpiece **(b)**.

Although, VASER-assisted lipoplasty typically takes longer than standard suction-assisted lipoplasty due to the extra step required for emulsification of adipose tissue before aspiration, the technology has several advantages. Fine probes and tunable power allow delicate and superficial tissues to be treated without causing unwanted irregularities. The unique pulsed (VASER) mode also halves the energy delivered to the tissues and represents an important feature for subdermal clearance of fat without causing complications. In order to treat fibrous tissue such as the back or male breasts, the power output is increased, continuous ultrasound is selected, and a more aggressive probe is selected. The cavitation and mechanical forces that are produced with the VASER probes vibrating at ultrasonic frequencies disrupt relatively weak adipose tissue much more readily than more dense tissue such as vessels, nerves, and fibrous septae. As a result, there is a selective emulsification of fat with sparing of surrounding tissues. This translates to less bleeding, less bruising, and an easier and more rapid recovery for the patient than suction-assisted lipoplasty. The majority of fat aspirated following treatment with VASER is viable. This is particularly important for high-definition body sculpting where large volumes of fat grafts may be used to contour the buttocks, hips, or breasts.

Consequently, this technology allowed the surgeon to perform better procedures, with less complications and for sure, a new era of body sculpting was ahead. In the next paragraphs we will explain deeply about VASER and its benefits, but focusing on its use in high definition body sculpting.

11.1.2 VASER Physics: How it Works?

VASER technology is somehow different from previous generations of ultrasound as we discussed above. The main difference compared to other devices is the way the energy is delivered to the tissues: not just ultrasound but resonance. This is a physical effect seen in nature and many other disciplines rather than electronics. This concept is based in two notions: one is that the frequency of the device (36 mHz) is closest to the resonance of fat. While fat vibrates, it gets emulsified with less power delivered. The second notion is the cell size: comparatively, fat cells are 10 times bigger than other cells around (blood vessels, nerves, connective tissue), making fat more sensitive to the ultrasonic energy than the other tissues.

Most ultrasound surgical instruments oscillate or vibrate between 20 kHz and 60 kHz. VASER employs probes that oscillate 36,000 times per second as we mentioned before, so its technology allows safe and efficient emulsification of fat in all subcutaneous layers, including the superficial subdermal layer, preserving as much of the tissue matrix as possible, yet still remove the desired amount of fatty tissue. They designed smaller diameter solid probes (2.2–4.5 mm) and a unique grooved tip design to emulsify fat efficiently at 36 kHz, but also preserving surrounding tissues and structures. The correct application and treatment with VASER enables smooth, even results and optimizes postoperative skin retraction. This device is also an excellent tool to facilitate fat harvesting, stem cell decantation and then grafting during the body contouring procedure.

Consequently, the therapeutic effect has a thermal and a non thermal mechanism depending on the interaction of the wave with the tissue. Cavitation occurs when there is enough air in the tissue where bubbles are created, vibrate and oscillate around an equilibrium ratio which produces high pressures and high temperature. The acoustic radiation happens when the momentum is transferred from the sound field to the object (▶Fig. 11.2).