INTRODUCTION
Non-invasive body contouring continues to gain popularity in the United States and the field is advancing at a fast pace. In fact, it the fastest growing category among dermatologic procedures. In 2014 alone, over 207,000 body sculpting procedures were performed by American Society for Dermatologic Surgery (ASDS) members.1 While this includes tumescent liposuction, the vast majority of cases are using non-invasive methods. This is a dramatic 53% increase from 2012, and a 16% increase from 2013.1 Many factors can play a role in a patient’s decision to have a cosmetic procedure. The 2015 ASDS Consumer Survey revealed that dermatologists have the most influence on patients, ranking above plastic surgeons, primary care physicians, friends, websites, and other factors.2 Therefore, dermatologists have a responsibility to be well-informed and familiar with the fast growing category of non-invasive body contouring technologies. Various technologies exist today including cryolipolysis, radiofrequency, ultrasound, injection lipolysis, and laser. The concept of the direct action of lasers on adipose tissue, termed laser lipolysis, was first pioneered by Apfelberg in 1992.3 At this time, laser lipolysis was introduced as an adjunct to traditional surgical liposuction. It wasn’t until 2006 that the FDA approved the first laser lipolysis device, which was an Nd:YAG 1064 nm laser. Laser-assisted liposuction led to superior fat reduction, decreased blood loss and ecchymoses, and improved skin tightening. These benefits are due to adipocyte membrane disruption, coagulation of blood vessels, and collagen remodeling.3 It is generally accepted that these effects are primarily due to the heat generated by the laser. When advancing to a non-invasive approach to laser lipolysis, an external device is required. However, when creating an external device that uses heat as its mechanism of action, there is a risk of thermal injury to the skin causing discomfort or more significant side effects. Therefore, the initial application of lasers to the elds of noninvasive body contouring was with low-level laser therapy or "cold laser". This modality creates temporary microscopic pores within the cell membrane of the adipocytes, through a cytochrome oxidase interaction, allowing the triglyceride contents to leave these damaged cells.4 There is no measurable rise in temperature of the treated tissue. The application of the 1060 nm diode laser for fat reduction is the first and only FDA cleared hyperthermic laser for non-invasive body contouring. This device successfully and safely uses the thermal effects of an external laser to non-invasively destroy adipose tissue. Herein we will describe the mechanism of action, efficacy, and safe nature of this novel modality.
Mechanism of Action
The 1060 nm diode laser leads to injury of the adipocytes through direct heating of the tissue. Energy delivered by the laser creates movement within the molecules of the exposed tissue, which then generates heat. A controlled temperature of 42-47 ?C must be maintained at the site of the adipocytes. At this hyperthermic temperature, the cell membranes of the
