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


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.
Wanner
Molly
M
Department of Dermatology, Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA. mwanner@partners.org
Avram
Mathew
M
Gagnon
Denise
D
Mihm
Martin C
MC
Zurakowski
David
D
Watanabe
Kanna
K
Tannous
Zeina
Z
Anderson
R Rox
RR
Manstein
Dieter
D
D000328:Adult; D015331:Cohort Studies; D020405:Dermis / Q000473:pathology / Q000528:radiation effects; D004307:Dose-Response Relationship, Radiation; D004817:Epidermis / Q000473:pathology / Q000528:radiation effects; D005260:Female; D006801:Humans; D053685:Laser Therapy / Q000009:adverse effects / Q000379:methods*; D054023:Lasers, Semiconductor / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000209:etiology / Q000473:pathology; D010865:Pilot Projects; D050507:Subcutaneous Fat, Abdominal / Q000473:pathology / Q000528:radiation effects*; D055815:Young Adult