Soft Tissue Ablation by Nanosecond Laser Pulses

Description

The application of nanosecond laser pulses in ablation-based laser surgery continues to increase owing to the high ablation precision and to the reduction in collateral tissue damage. This, however, has not been accompanied by a clear understanding of the fundamental mechanism. Three major models have been used to explain the soft tissue ablation by nanosecond laser pulses in a spectral region from far ultraviolet to near-infrared. The aims of this proposal are: to achieve a clear understanding of the fundamental mechanism underlying soft tissue ablation by nanosecond laser pulses; and to provide practical guidelines for substantial improvements in the surgical laser design.

Based on the in vitro study if skin ablation, we have investigated new approaches of delivering short pulsed laser pulses to treat skin lesions in a micropig animal model. From our recently conducted preliminary study in two micropigs, we have successfully  reduced the single pulse energy to 60mJ or lower with 12ns pulses at 1064nm in tattoo removal. Future animal and human studies, we will investigate the possibility of reducing further the single pulse energy which can minimize collateral tissue damage and offer the possibility of treating multi-color pigmented lesions with a single-wavelength laser pulses.   

Publications

· X.H. Hu, "Efficient use of Q-switched lasers in the treatment of cutaneous lesions", SPIE Proceedings, 2395, 586-591 (1995)

· X.H. Hu, Q. Fang, M. Cariveau, X. Pan, G.W. Kalmus, "Mechanism Study of Porcine Skin Ablation by Nanosecond Laser Pulses at 1064, 532, 266 and 213nm ", IEEE Journal of Quantum Electronics,  37, 322-328 (2001)

· X.H. Hu, W. A. Wooden, M. Cariveau, Q. Fang, G.W. Kalmus, S.J. Vore, “Study of Tattoo Clearance with Small-energy Pulses at 1064nm in Micropigs”, Lasers in Medical Sciences, 17, 154-164 (2002)

· Q. Fang, X.H. Hu, “Modeling of Skin Tissue Ablation by Nanosecond Pulses from Ultraviolet to Near-infrared and Comparison with Experimental Results", IEEE Journal of Quantum Electronics, 40, 69-77 (2004)