Source
Wellman Center for Photomedicine, Harvard Medical School, Boston, Massachusetts, USA. RRAnderson@partners.org
Abstract
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.
(c) 2006 Wiley-Liss, Inc.