Histopathological Analysis of Abdominal Skin and Fat After In Vivo Hyperthermia-Induced Lipolysis With a 1064 nm Diode Laser, Radiofrequency, and Electromagnetic Field: A Pilot Study

Abstract Background Hyperthermic laser lipolysis safely reduces unwanted fat through controlled thermal injury of adipocytes. Objectives To assess the effects of 1064 nm laser, single vs multiple treatments, with and without radiofrequency (RF) and pulsed electromagnetic field (PEMF) energy on abdominal tissue. Methods Nine volunteers scheduled for elective abdominoplasty were divided into 1 of 3 arms: (1) laser alone, (2) laser with and without RF and PEMF, and (3) multiple vs single laser treatments. Untreated (control) and treated tissues were collected at various time points following treatment. Paraffin sections from surgically excised pannus were evaluated with Masson's trichrome, apoptosis (TUNEL), Collagen 1, Collagen 3, Elastin, and CD68 macrophage markers. Results All study arms showed subdermal adipose tissue lysis without compromising epidermal or dermal integrity. Apoptotic adipocytes and macrophage infiltration were present in areas of structural damage. Adjuvant RF and PEMF showed increased macrophage infiltration after 14 days. Multiple 1064 nm treatments induced apoptosis in subcutaneous adipocytes. There were no significant changes in dermal Collagen 1, Collagen 3, and elastin abundance. Conclusions The 1064 nm diode laser can destroy adipocytes without harming overlying epidermis. RF enhances lipolytic effects of the laser with increased inflammation and tissue remodeling, whereas PEMF therapy uses electromagnetic fields to stimulate cell function and tissue repair. These findings suggest the 1064 nm diode laser can achieve intended effects. Level of Evidence: 3 (Therapeutic)