In this preliminary study, four lasers were compared for noninvasive creation of deep subsurface thermal lesions.  The optimal laser wavelength tested for creation of deep subsurface thermal lesions during contact cooling of tissues was 1075 nm, which preserved a surface layer of ~ 2 mm.  The Ytterbium fiber laser provides a compact, low maintenance, and high power alternative laser source to the Neodymium:YAG laser for noninvasive thermal therapy.
THERM