Interplay of wavelength, fluence and spot-size in free-electron laser ablation of cornea.
نویسندگان
چکیده
Infrared free-electron lasers ablate tissue with high efficiency and low collateral damage when tuned to the 6-microm range. This wavelength-dependence has been hypothesized to arise from a multi-step process following differential absorption by tissue water and proteins. Here, we test this hypothesis at wavelengths for which cornea has matching overall absorption, but drastically different differential absorption. We measure etch depth, collateral damage and plume images and find that the hypothesis is not confirmed. We do find larger etch depths for larger spot sizes--an effect that can lead to an apparent wavelength dependence. Plume imaging at several wavelengths and spot sizes suggests that this effect is due to increased post-pulse ablation at larger spots.
منابع مشابه
Abstract Submitted for the MAR07 Meeting of The American Physical Society Confounding Effect of Spot-Size on the Wavelength-Dependence of Tissue Ablation Metrics1 M. SHANE HUTSON, GILMA ADUNAS, YAOWU
Submitted for the MAR07 Meeting of The American Physical Society Confounding Effect of Spot-Size on the Wavelength-Dependence of Tissue Ablation Metrics1 M. SHANE HUTSON, GILMA ADUNAS, YAOWU XIAO, Vanderbilt University — Tunable free-electron lasers have been used in several previous studies to investigate the mid-IR wavelength-dependence of tissue ablation. These studies gave conflicting resul...
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ورودعنوان ژورنال:
- Optics express
دوره 17 12 شماره
صفحات -
تاریخ انتشار 2009