Quantitative Imaging of the Iron-Oxide Nanoparticle- Concentration for Magnetic Drug Targeting Employing Inverse Magnetomotive Ultrasound

Abstract

Magnetomotive Ultrasound is an imaging technique that is capable to detect tissue, which is perfused by magnetic nanoparticles. However, this modality is restricted to qualitative imaging only. Therefore, we present an extended Magnetomotive Ultrasound algorithm, which allows the quantitative determination of the spatial distribution of magnetic nanoparticle density in tissue. The algorithm is based on an iterative adjustment of simulated data to measurements. Experiments with tissue-mimicking phantoms reveal that the presented method leads to the spatial particle concentration in the correct order of magnitude.

External Power-Driven Microrobotic Swarm: From Fundamental Understanding to Imaging-Guided Delivery

“…(f) Observation of nanoparticle region with B-mode imaging, common MMUS, and inverse MMUS in a tissue-mimicking phantom. Reproduced with permission from ref . Copyright 2019 De Gruyter.…”

Displacement Patterns in Magnetomotive Ultrasound Explored by Finite Element Analysis

“…Their contributions to the vertical component are seen in Figure 3, where the magnitude of this component is approximately 30% larger at 10 mm off-center, as compared with the approximation. This illustrates how the force magnitude varies spatially within the image plane, which is important to take into account in any type of quantitative evaluation (Fink et al 2019). Furthermore, the magnitude of the horizontal component in this position is approximately half of the vertical, indicating that the force vector in this position is directed inward, toward the tip of the iron core.…”

Magnetic mediators for ultrasound theranostics

“…This movement allows for identification of tissues that have taken up SPIONs from their surroundings ( Figure 6 A ) 135 - 137 . Several variations of MMUS have already been developed, including pulsed MMUS 138 , backward MMUS 139 , inverse MMUS 140 , magnetomotive optical Doppler tomography 141 , and MMUS to create tomographic images ( Figure 6 B-C ) 142 . Frequency and phase tracking MMUS algorithms have been successfully evaluated in simulations, in vitro , in vivo , and postmortem in rat models 131 , 135 , 143 , 144 .…”

“…C. B-mode image of a tissue-mimicking phantom with MNPs (left), common MMUS evaluation of raw US data (center), and evaluation according to the inverse MMUS algorithm (right). Adapted with permission from 140 , copyright 2019 De Gruyter.…”