Effects of non-invasive, 1,210 nm laser exposure on adipose tissue: results of a human pilot study

Lasers Surg Med. 2009 Aug;41(6):401-7. doi: 10.1002/lsm.20785.


Background and objectives: Laser radiation (1,210 nm) has been previously shown to be capable of selective photothermolysis of adipose tissue in vitro when applied non-invasively. The objective of this pilot study was to evaluate the in vivo effects of this laser in human subjects.

Study design/materials and methods: Twenty-four adult subjects were exposed non-invasively on the abdomen to a 1,210 nm laser at fluences of 70, 80, and 90 J/cm(2), with a 10 mm spot size, 5 seconds pre-cooling, and 3 seconds exposure duration delivered with parallel contact cooling. There was an impairment of the skin-cooling device during the study. Exposure and control sites were biopsied at either 1-3 days or 4-7 weeks. Tissue was processed for nitroblue tetrazolium chloride (NBTC) staining, a marker for thermal damage, and hematoxylin and eosin (H&E) staining.

Results: Laser exposures were painful, requiring local anesthesia in most subjects, but otherwise well tolerated. At 1-3 days after exposure, there was a fluence-dependent loss of NBTC staining in the fat and dermis. In 2 of 14 subjects (2 of 42 exposure sites) evaluated at 1-3 days after exposure, epidermal damage was noted within a small portion of the test site, likely due to impaired contact cooling. At 4-7 weeks, lipomembranous changes of the fat were seen in 89% of test sites and 33% of control sites.

Conclusions: This in vivo study shows histologic evidence of laser-induced damage of fat. With further development, this might become a useful treatment for disorders involving the fat and/or lower dermis.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Cohort Studies
  • Dermis / pathology
  • Dermis / radiation effects
  • Dose-Response Relationship, Radiation
  • Epidermis / pathology
  • Epidermis / radiation effects
  • Female
  • Humans
  • Laser Therapy / adverse effects
  • Laser Therapy / methods*
  • Lasers, Semiconductor* / adverse effects
  • Male
  • Middle Aged
  • Pain / etiology
  • Pain / pathology
  • Pilot Projects
  • Subcutaneous Fat, Abdominal / pathology
  • Subcutaneous Fat, Abdominal / radiation effects*
  • Young Adult