Photodisruption in biological tissues and single cells using femtosecond laser pulses

Summary form only given. Semi-transparent materials such as biological tissues do not strongly absorb light in the visible range. However, the intensity of a tightly-focused femtosecond laser pulse can be high enough to cause nonlinear absorption of laser energy by the tissue, leading to permanent material change. The nonlinearity of the process ensures the absorption, and therefore material alterations are confined to the extremely small focal volume. In this paper, we show that sub-micrometer sized photodisrupted regions can be produced inside single cells by nonlinear absorption of tightly focused femtosecond laser pulses. Femtosecond pulses deposit very little energy while still causing breakdown, therefore producing surgical photodisruption while minimizing collateral damage (Juhasz et al, 1995; Zysset et al, 1989; Krauss and Puliafito, 1996). This suggests exciting prospects for precise laser surgery.