Open AccessPotential of sub-microsecond laser pulse shaping for controlling microcavitation in selective retinal therapies
Author(s) -
Pascal Deladurantaye,
Sébastien Méthot,
Ozzy Mermut,
Pierre Galarneau,
Patrick J. Rochette
Publication year - 2019
Publication title -
biomedical optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.362
H-Index - 86
ISSN - 2156-7085
DOI - 10.1364/boe.11.000109
Subject(s) - microsecond , laser , nanosecond , materials science , optics , picosecond , pulse (music) , ultrashort pulse , optoelectronics , physics , detector
Pilot results showing the potential of sub-microsecond laser pulse shaping to optimize thermomechanical confinement in laser-tissue interactions involving microcavitation are presented. Model samples based on aqueous suspensions of retinal melanosomes and eumelanin particles were irradiated at 532 nm with nanosecond laser pulses and picosecond laser pulse trains having differing shapes and durations. The cavitation threshold radiant exposure and the bubble lifetime above the threshold were measured using a pump-probe setup and sub-nanosecond time-resolved imaging. Both quantities were found to strongly depend on the pulse format. These results suggest that sub-microsecond laser pulse shaping could be exploited to optimize precision and control in numerous applications of laser-directed microcavitation, including selective retinal laser treatments.