Texture Generation for Photoacoustic Elastography

TL;DR

This paper demonstrates that artificial speckle patterns can be generated in photoacoustic imaging using band-limited data, enabling more reliable elastography deformation estimation in this modality.

Contribution

It introduces a novel method to create artificial speckle patterns in photoacoustic imaging, facilitating elastography applications where speckle is absent.

Findings

Artificial speckle patterns can be generated from band-limited data.

Deformation estimation becomes more reliable with artificial speckles.

Photoacoustic elastography can be enhanced using this approach.

Abstract

Elastographic imaging is a widely used technique which can in principle be implemented on top of every imaging modality. In elastography, the specimen is exposed to a force causing local displacements in the probe, and imaging is performed before and during the displacement experiment. From the computed displacements material parameters can be deduced, which in turn can be used for clinical diagnosis. Photoacoustic imaging is an emerging image modality, which exhibits functional and morphological contrast. However, opposed to ultrasound imaging, for instance, it is considered a modality which is not suited for elastography, because it does not reveal speckle patterns. However, this is somehow counter-intuitive, because photoacoustic imaging makes available the whole frequency spectrum as opposed to single frequency standard ultrasound imaging. In this work, we show that in fact artificial speckle patterns can be introduced by using only a band-limited part of the measurement data. We also show that after introduction of artificial speckle patterns, deformation estimation can be implemented more reliably in photoacoustic imaging.