Skin damage thresholds with continuous-wave laser exposures at the infrared wavelength of 1319 nm

Infrared skin damage thresholds from 1319-nm continuous-wave laser exposures

“…Some damage threshold studies have been completed at 1315 nm for pulses in the microsecond regime, as reported by Cain et al 8 A preliminary skin damage threshold study at 1214 and 1319 nm has also been documented. [9][10][11] The Yucatan miniature pig has been established as a model for human skin damage studies due to the morphological and physiological similarities to human skin. 12 This study at 1319 nm, as compared to 2000 nm, allows for conditions where damage can be produced at a more optically penetrating wavelength, but again with relatively large beam diameters and exposure durations up to 10 s. The use of large laser-beam diameters results in a measured threshold under conditions near the theoretical one-dimensional limit of heat transfer in the skin, where radial heat losses from the center of the beam-tissue interface are negligible with respect to losses due to axial heat transfer.…”

“…A detailed analysis of the beam profile for this study has been presented previously. 11 The laser was characterized with an Electrophysics MicronViewer 7290 A, IR Camera (Electrophysics, Fairfield, NJ), and Pyrocam beam analysis software (Spiricon, Logan, UT) beam profiler. The beam diameters (D4σ) were measured to be 0.61 AE 0.01 and 0.97 AE 0.02 cm on average by repeated measure at the target plane prior to exposure.…”

Computer modeling of laser induced injury of the skin

“…The in-vivo models were Yorkshire, White, Handford (lightly pigmented), Yucatan (strongly pigmented) porcine flanks and lightly/strongly pigmented human forearms. References are [1,2,4,9,13,14,15,16,17,18,19,20,21,22] (see also Paper by Bruce Stuck et al in these proceedings). Data given at ≤1h-and 24/48hreadings were pooled together since the average ratio is 1.08 (18 data couples).…”