Er:YAG lasers are being widely studied as candidates for surgical procedure
s in liquid environments, such as in ophthalmology, However, while the Er:Y
AG laser can be a precise and efficient light scalpel, this surgical method
includes accompanying stress waves that must be quantified and evaluated f
or potential harm. In this study, Er:YAG laser-induced stress waves for fre
e running laser pulses were measured over various consecutive treatment per
iods. Using a spot-poled PVDF hydrophone, measurements were acquired beneat
h a biological membrane submerged in a saline bath, Results yielded pressur
es peaks of 300-600 mbar beneath the uncut membrane, which could be harmful
for the optic nerve if located directly below the treatment area. Acoustic
waves representative of direct laser-liquid interactions were observed imm
ediately following membrane rupture, and yielded much larger pressures. The
morphological changes in the acoustic wave can be used as a feedback signa
l to indicate when the membrane has been cut.