Plasma and cavitation dynamics during pulsed laser microsurgery in vivo

TL;DR

This study compares plasma and cavitation dynamics during pulsed laser microsurgery in water and in vivo in fruit fly embryos, revealing lower plasma thresholds and constrained cavitation bubble growth in vivo, affecting tissue disruption.

Contribution

It provides new insights into how biological tissues influence plasma formation and cavitation during laser microsurgery, highlighting differences from water-based models.

Findings

Lower plasma-formation thresholds in vivo, especially at 355 nm

Constrained cavitation bubble growth in biological tissue

Reduced tissue disruption compared to water-based extrapolations

Abstract

We compare the plasma and cavitation dynamics underlying pulsed laser microsurgery in water and in fruit fly embryos (in vivo) - specifically for nanosecond pulses at 355 and 532 nm. We find two key differences. First, the plasma-formation thresholds are lower in vivo - especially at 355 nm - due to the presence of endogenous chromophores that serve as additional sources for plasma seed electrons. Second, the biological matrix constrains the growth of laser-induced cavitation bubbles. Both effects reduce the disrupted region in vivo when compared to extrapolations from measurements in water.