Detection and numerical simulation of optoacoustic near- and farfield signals observed in PVA hydrogel phantoms

TL;DR

This paper develops a numerical simulation framework for modeling optoacoustic signals in PVA hydrogel tissue phantoms, capturing near- and farfield signals in various detection modes, and benchmarks the approach against simplified models and literature data.

Contribution

It introduces a comprehensive 3D computational method for simulating optoacoustic signals in elastic solid phantoms, including near- and farfield analysis and validation against existing models.

Findings

The simulation accurately reproduces experimental OA signals in PVA hydrogels.

The 3D model aligns well with 1D limiting cases and literature data.

The approach enhances understanding of OA signal generation in elastic media.

Abstract

We present numerical simulations for modelling optoacoustic (OA) signals observed in PVA hydrogel tissue phantoms. We review the computational approach to model the underlying mechanisms, i.e. optical absorption of laser energy and acoustic propagation of mechanical stress, geared towards experiments that involve absorbing media only. We apply the numerical procedure to model signals observed in the acoustic near- and farfield in both, forward and backward detection mode, in PVA hydrogel tissue phantoms (i.e. an elastic solid). Further, we illustrate the computational approach by modeling OA signal for several experiments on dye solution (i.e. a liquid) reported in the literature, and benchmark the research code by comparing our fully 3D procedure to limiting cases described in terms of effectively 1D approaches.