The survival, proliferation, and differentiation of freshly isolated and cultured cells were studied after absorbing film-assisted laser-induced forward transfer. Rat Schwann and astroglial cells and pig lens epithelial cells were used for transfer and the cells were cultured for 2 weeks after laser-pulsed transfer. All three cell types survived, proliferated, and differentiated under cell culture conditions and regained their original phenotype a few days after cell transfer. Time resolution studies have shown that the time required to accelerate the jets and droplets containing the cells was less than 1 micros and that the estimated minimum average acceleration of those ejected cells that reached a constant velocity was approximately 10(7) x g. This suggests that the majority of studied cells tolerated the extremely high acceleration at the beginning of the ejection and the deceleration during impact on the acceptor plate without significant damage to the original phenotype. These results suggest that the absorbing film-assisted laser-induced forward transfer technique appears to be suitable for several potential applications in tissue engineering and the biomedical tissue repair technologies.

The creation of the LASIK flap alone can modify the eye's optical characteristics in low-order aberrations and HOAs. A significant increase in HOAs was seen in the Hansatome group but not in the IntraLase group. This may have significant clinical implications in wavefront-guided LASIK treatments, which are based on measurements made before flap creation.

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Large temporal front distortion of femtosecond pulses occurs in lenses having chromatic aberration. The effect is due to the difference between the phase and group velocities. Equations describing the pulse-front delay in singlet lenses, achromats, and compound lenses are presented. The pulse-front delay is several orders of magnitude larger than the broadening caused by group-velocity dispersion in the lens material. Delays occurring in Fresnel-type zone plates are also described.

Background and Objective Photodisruption in ocular media with high power pulsed lasers working at non‐absorbing frequencies have become a well established surgical tool since the late seventies. Shock waves and cavitation bubbles generated by the optical breakdown may strongly influence the surgical effect of photodisruptive lasers. We have investigated the shock wave and cavitation bubble effects of femtosecond laser pulses generated during photodisruption in corneal tissue and water. The results are compared to those obtained with longer laser pulses. Study Design/Materials and Methods Laser pulses with 150 fs duration at ∼620 nm wavelength have been focused into corneal tissue and water to create optical breakdown. Time‐resolved flash photography has been used to investigate the dynamics of the generated shock waves and cavitation bubbles. Results A rapid decay of the shock waves is observed in both materials with similar temporal characteristics and with a spatial range considerably smaller than that of shock waves induced by picosecond (or nanosecond) optical breakdown. Cavitation bubbles are observed to develop more rapidly and to reach smaller maximum diameter than those generated by longer pulses. In corneal tissue, single intrastromal cavitation bubbles generated by femtosecond pulses disappear within a few tens of seconds, notably faster than cavitation bubbles generated by picosecond pulses. Conclusions The reduced shock wave and cavitation bubble effects of the femtosecond laser result in more localized tissue damage. Therefore, a more confined surgical effect should be expected from a femtosecond laser than that from picosecond (or nanosecond) lasers. This indicates a potential benefit from the applications of femtosecond laser technology to intraocular microsurgery. © 1996 Wiley‐Liss, Inc.