Tissue ablation by a free-electron laser tuned to the amide II band

  title={Tissue ablation by a free-electron laser tuned to the amide II band},
  author={Glenn S. Edwards and Regan Logan and Michael Copeland and Lou Reinisch and J. L. Davidson and Bruce Johnson and Robert J. Maciunas and Marcus H. Mendenhall and Robert H. Ossoff and Jerri A. Tribble and Jay A. Werkhaven and Denis M. O'day},
EFFORTS to ablate soft tissue with conventional lasers have been limited by collateral damage and by concern over potential photochemical effects1–5. Motivated by the thermal-confinement model6, past infrared investigations targeted the OH-stretch mode of water with fast pulses from lasers emitting near 3,000 nm (refs 1, 7–9). What does a free-electron laser offer for the investigation of tissue ablation? Operating at non-photochemical single-photon energies, these infrared sources can produce… 

Tissue ablation with the free-electron laser: contributions of wavelength and pulse structure

The Vanderbilt free-electron laser provides a continuously tunable ((lambda) equals 2 - 10 micrometer) source of pulsed IR radiation with a pulse structure unlike those of conventional lasers (a

Free electron laser ablation of soft tissue : the effects of chromophore and pulse characteristics on ablation mechanics.

It appears that over a very broad range of midinfrared wavelengths, the results of soft tissue ablation with the FEL are well described by a steady-state ablation model that incorporates the effect of plume screening, and the fundamental mechanism appears to be a water absorption dominated process.

Analysis of infrared laser tissue ablation

The mechanisms involved in infrared laser tissue ablation are studied using a free electron laser (FELIX) in order to clarify whether the increased ablation efficiency reported in literature for

Pulse-Duration-Dependent Mid-Infrared Laser Ablation for Biological Applications

There are significant benefits to medical laser surgeries performed with mid-infrared wavelengths, including the ability to select laser parameters in order to minimize photochemical and thermal

Wavelength-dependent collagen fragmentation during mid-IR laser ablation.

This report analyzes the nonvolatile debris ejected during ablation of porcine corneas with a free-electron laser to find that high-fluence ablation at 6.45 microm, but not at 2.77microm, leads to protein fragmentation accompanied by the accumulation of nitrile and alkyne species.

The role of chromophore on pulsed laser ablation of biological tissue

Despite the widespread use of pulsed lasers in biomedical applications, the physicochemical mechanisms and dynamics of ablation processes remain unclear. The role of chromophore on pulsed infrared

Mid infrared optical parametric oscillator (OPO) as a viable alternative to tissue ablation with the free electron laser (FEL)

This research compared a Mark‐III FEL and an Er:YAG pumped ZGP‐OPO with respect to the effect of pulse duration on ablation efficiency and thermal damage on porcine cornea.

The effect of free-electron laser pulse structure on mid-infrared soft-tissue ablation: ablation metrics

There is a small effect of micropulse duration of the FEL on the ablation process; however, this effect is negligible between 1 and 200 ps given that there is a 200-fold decrease in peak intensity.

Laser selective cutting of biological tissues by impulsive heat deposition through ultrafast vibrational excitations.

Highly efficient ablation of healthy tooth enamel using 55 ps infrared laser pulses tuned to the vibrational transition of interstitial water and hydroxyapatite is demonstrated, attributed to an enhanced photomechanical effect due to ultrafast vibrational relaxation into heat and the scattering of powerful ultrafast acoustic transients with random phases off the mesoscopic heterogeneous tissue structures.

Analysis of soft tissue ablation using the pulse stretched free electron laser

In this study, the native pulse structure of the FEL, a 2.85 gigahertz repetition of picosecond pulses within a five microsecond macropulse envelope, was changed using a pulse stretcher to reduce the peak intensity of the micropulse down to 1/200th of the original intensity, while the macrop Pulse energy remains unchanged.



Biomedical applications of free-electron lasers

Tunable, pulsed radiation sources in the ultraviolet, visible, and infrared wavelength ranges offer novel opportunities for investigating laser-induced biomedical effects. Free-electron lasers (FELs)

Picosecond optical breakdown: Tissue effects and reduction of collateral damage

The effects of picosecond laser‐induced optical breakdown on tissue were investigated using high‐intensity 40 ps Nd:YAG laser pulses at 1.06 μm to demonstrate a significant reduction in collateral tissue damage.

Ablation of polymers and biological tissue by ultraviolet lasers.

Dry photoetching technique, when pulsed, ultraviolet laser radiation falls on the surface of an organic polymer or biological tissue, the material at the surface is spontaneously etched away to a depth of 0.1 to several micrometers.

Er:YAG laser ablation of tissue: Effect of pulse duration and tissue type on thermal damage

The thermal damage caused by 2.94‐μm Er:YAG laser ablation of skin, cornea, aorta, and bone was quantified and the zone of residual thermal damage produced by normal‐spiking‐mode pulses and Q‐switched pulses was compared.

Application of a two-color free-electron laser to condensed-matter molecular dynamics

The possible applications of a free-electron laser (FEL), which would be modified to produce two synchronized, independently tunable picosecond pulses, are considered. At least one of the pulses

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Hemodynamic, histological, and ultrastructural responses are discussed and a simple, predictive model is presented, showing selective damage to cutaneous microvessels and melanosomes within melanocytes after selectively absorbed optical radiation pulses.

Picosecond infrared vibrational photon echoes in a liquid and glass using a free electron laser.

The first infrared vibrational photon echo experiments conducted in a liquid and a glass and the first vibrational population relaxation measurements spanning a temperature range that takes a system from a liquid to a supercooled liquid toA glass are reported.

Stimulated Emission of Bremsstrahlung in a Periodic Magnetic Field

The Weizsacker‐Williams method is used to calculate the gain due to the induced emission of radiation into a single electromagnetic mode parallel to the motion of a relativistic electron through a