Device-assisted liposuction: the evidence on ultrasound and laser

What is device-assisted liposuction?

Since it was introduced more than 30 years ago, liposuction has advanced considerably and has become one of the most commonly performed procedures in cosmetic surgery ^[1]. A thin tube (cannula) connected to a suction device is inserted through a small incision to remove the fat under the skin, and the procedure is described as effective for reducing localized fat in people who are not generally obese ^[1].

Device-assisted liposuction adds energy or mechanical movement to this basic method. The techniques currently in use are standard suction (suction-assisted), ultrasound-assisted, power-assisted, laser-assisted, and radiofrequency-assisted liposuction ^[1]. Ultrasound, laser, and radiofrequency act on fat tissue through energy, while in power-assisted liposuction the cannula itself moves rapidly to help with suction. Which technology and technique to use is often decided based on the patient's characteristics and the surgeon's preference ^[1].

Evidence compared with standard liposuction

A 2018 review selected, out of 9972 articles, the 25 that directly compared standard suction with ultrasound-assisted or laser-assisted methods, and it excluded studies sponsored by manufacturers ^[2]. It found advantages over the standard method in three areas: ultrasound assistance in treating enlarged male breasts (gynecomastia), laser and ultrasound assistance in causing a smaller drop in hemoglobin and hematocrit (the proportion of red blood cells in the blood) when large volumes were removed, and laser assistance in tightening the skin in some areas, such as under the chin ^[2].

Beyond these, the results were mixed across methods, making it hard to say that any one was clearly better, and the authors concluded that apart from these exceptions, no added benefit was found that would justify adding ultrasound or laser ^[2]. For power-assisted and radiofrequency-assisted methods, the research summaries used for this article did not present results compared with the standard method.

What is known about laser-assisted liposuction

A 2018 systematic review analyzed the 7 of 80 studies that met its criteria, and 5 of them reported benefits of laser-assisted liposuction ^[3]. The outcomes compared were tissue findings under the microscope (histologic analysis, 2 studies), a greater reduction in fat under the skin (2 studies), better skin contraction (3 studies), and higher patient satisfaction (2 studies) ^[3]. However, the review stated that the risk of bias was high in several domains, making it difficult to reach more reliable conclusions ^[3].

A 2012 review described laser-assisted lipolysis as a method that aims to use laser energy to break down fat, help control bleeding, and stimulate the formation of new collagen ^[4]. Of the 19 studies it reviewed, only 1 was a double-blind randomized controlled trial comparing the laser method with tumescent liposuction; objective comparisons with the tumescent method were lacking, and laser energy settings were not standardized ^[4]. While the authors considered laser lipolysis safe and effective, they stated that it had not been proven to be better than tumescent liposuction ^[4].

The tumescent method and the safety of liposuction

Tumescent liposuction is a method in which a generous amount of fluid containing a local anesthetic is injected into the fat layer before the fat is suctioned out. A 2011 review explained that this method can remove a large amount of fat while minimizing bleeding and problems after surgery, and it summarized that in data covering more than 100,000 body areas treated under tumescent anesthesia, there were no serious complications such as death, embolism, or perforation of the chest cavity or the peritoneum (the lining of the abdomen) ^[5].

On the other hand, the same review stated that deep vein thrombosis or pulmonary embolism, perforation of abdominal organs, infection, and bleeding had been reported with liposuction performed under general anesthesia, and that European survey data analyzed 72 serious complications of liposuction, including 23 deaths, over the 5 years from 1998 to 2002 ^[5]. The most common were bacterial infections such as necrotizing fasciitis ^[5]. Because this review placed data from different sources side by side, the differences cannot be attributed to the type of anesthesia alone, but it does show that liposuction is surgery that can, in rare cases, cause serious complications.

A word of caution on new devices and high-definition contouring

Techniques that sculpt deep and superficial fat separately have been introduced, such as abdominal etching, which brings out the outline of the abdominal muscles, but the article in question describes the authors' own technique ^[7]. Experience combining the concept of high-definition liposculpture with excisional surgery such as a tummy tuck (abdominoplasty) has also been reported, but because it includes surgery that removes skin, it should be considered separately from liposuction alone ^[8].

A 2020 article noted that nonsurgical and minimally invasive devices are increasingly used to complement or replace abdominoplasty, but it pointed out that lack of experience, conflicting anecdotal reports, energy-related complications, exaggerated marketing, and rapid turnover of technology are major barriers to their adoption ^[6]. When a new device is recommended to you, it is a good idea to look past the name of the device and also ask what comparative studies exist and how likely energy-related complications, such as heat injury, are.

Recovery and what to check during your consultation

Whatever device is used, swelling, bruising, and changes in sensation can occur after liposuction, and the contours may be left uneven. Based on the evidence used for this article, it is difficult to say that device-assisted methods speed up recovery. Results vary from person to person depending on the amount and distribution of fat, skin elasticity, and the extent of surgery, so it is best to decide on the method together with a specialist who has examined you in person.

• Which device will be used and why, and what evidence compares it with the standard method
• Additional risks from using the device, such as heat injury
• If your skin is sagging, what the device can realistically be expected to do
• The extent of surgery, the type of anesthesia, and the recovery period