An Enhanced Magnetomotive Ultrasound Algorithm to Quantitatively Estimate the Concentration of Iron-Oxide Nanoparticles in Perfused Tissue for Magnetic Drug Targeting

Numerous medical applications make use of magnetic nanoparticles, which boosts the demand for imaging systems that can visualize these particles. Magnetomotive Ultrasound (MMUS) is an ultrasound-based imaging modality that can detect tissue perfused with magnetic nanoparticles. However, MMUS can only provide a qualitative mapping of the particle-loaded tissue. Therefore, we introduce in this contribution an extension of the MMUS algorithm that enables a quantitative representation of the nanoparticle density distribution in tissue. The presented algorithm is based on an iterative comparison between simulated data and measured data. Experiments with tissue-mimicking phantoms reveal that the presented procedure can be used to determine the local nanoparticle concentration in the correct order of magnitude.