Related Experiment Video
Updated: Jul 18, 2026
Continuous-wave Thulium Laser for Heating Cultured Cells to Investigate Cellular Thermal Effects
Published on: June 30, 2017
Selective photothermolysis of lipid-rich tissues: a free electron laser study
R Rox Anderson1, William Farinelli, Hans Laubach
1Wellman Center for Photomedicine, Harvard Medical School, Boston, Massachusetts, USA. RRAnderson@partners.org
Background And Objectives:
In theory, infrared vibrational bands could be used for selective photothermolysis of lipid-rich tissues such as fat, sebaceous glands, or atherosclerotic plaques.
Study Design/Materials And Methods:
Absorption spectra of human fat were measured, identifying promising bands near 1,210 and 1,720 nm. Photothermal excitation of porcine fat and dermis were measured with a 3.5-5 microm thermal camera during exposure to the free electron laser (FEL) at Jefferson National Laboratory. Thermal damage to full-thickness samples exposed at approximately 1,210 nm through a cold contact window, was assessed by nitrobluetetrazolium chloride staining in situ and by light microscopy.
Results:
Photothermal excitation of fat was twice that of dermis, at lipid absorption bands (1,210, 1,720 nm). At 1,210 nm, a subcutaneous fat layer several mm thick was damaged by FEL exposure, without apparent injury to overlying skin.
Conclusion:
Selective photothermal targeting of fatty tissues is feasible using infrared lipid absorption bands. Potential clinical applications are suggested by this FEL study.
