Dual-Mode Volumetric Optoacoustic and Contrast Enhanced Ultrasound Imaging with Spherical Matrix Arrays

TL;DR

This paper introduces a dual-mode imaging system combining volumetric optoacoustic tomography and contrast-enhanced ultrasound using spherical matrix arrays, enabling detailed vascular and tissue imaging in vivo.

Contribution

A novel approach for integrating VOT and US contrast imaging with microbubbles and model-based inversion, overcoming array pitch limitations for enhanced deep tissue mapping.

Findings

Successful in vivo blood velocity mapping in mice

Enhanced resolution and contrast in tissue imaging

Effective combination of VOT and US modalities

Abstract

Spherical matrix arrays arguably represent an advantageous tomographic detection geometry for non-invasive deep tissue mapping of vascular networks and oxygenation with volumetric optoacoustic tomography (VOT). Hybridization of VOT with ultrasound (US) imaging remains difficult with this configuration due to the relatively large inter-element pitch of spherical arrays. We suggest a new approach for combining VOT and US contrast-enhanced imaging employing injection of clinically-approved microbubbles. Power Doppler (PD) and US localization imaging were enabled with a sparse US acquisition sequence and model-based inversion based on infimal convolution of total variation (ICTV) regularization. Experiments in tissue-mimicking phantoms and in vivo in mice demonstrate the powerful capabilities of the new dual-mode imaging system for blood velocity mapping and anatomical imaging with enhanced resolution and contrast.