Data from: Magnetic resonance and ultrasound contrast imaging of polymer-shelled microbubbles loaded with iron oxide nanoparticles

Sciallero, Claudia, University of Genoa

Balbi, Luca, University of Genoa

Paradossi, Gaio, University of Rome Tor Vergata

Trucco, Andrea, University of Genoa

Published Jul 05, 2016 on Dryad. https://doi.org/10.5061/dryad.8bp16

Cite this dataset

Sciallero, Claudia; Balbi, Luca; Paradossi, Gaio; Trucco, Andrea (2016). Data from: Magnetic resonance and ultrasound contrast imaging of polymer-shelled microbubbles loaded with iron oxide nanoparticles [Dataset]. Dryad. https://doi.org/10.5061/dryad.8bp16

Abstract

Dual-mode contrast agents (CAs) have great potential for improving diagnostics. However, the effectiveness of CAs is strictly related to both the solution adopted to merge the two agents into a single probe unit, and the ratio between the two agents. In this study, two dual-mode CAs for simultaneous magnetic resonance imaging (MRI) and ultrasound imaging (UI) were assessed. For this purpose, different densities of superparamagnetic iron oxide nanoparticles (SPIONs) were anchored to the external surface of polymer-shelled microbubbles (MBs) or were physically entrapped into the shell. In vitro static and dynamic experiments were carried out with a limited concentration of modified MBs (106 bubbles ml−1) by avoiding destruction during UI (performed at a peak pressure lower than 320 kPa) and by using a low-field MRI system (with a magnetic flux density equal to 0.25 T). Under these conditions, different imaging techniques, set-up parameters and SPION densities were used to achieve satisfactory detection of the CAs by using both UI and MRI. However, when the SPION density was increased, the MRI contrast improved, whereas the UI contrast worsened due to the reduced elasticity of the MB shell. For both UI and MRI, MBs with externally anchored SPIONs provided better performance than MBs with SPIONs entrapped into the shell. In particular, a SPION density of 29% with respect to the mass of the MBs was successfully tested.

Usage notes

Ultrasound data (two-dimensional matrices of data)

A MATLAB (The MathWorks, Inc., MA, USA) script reads the RF frames that were acquired by the ultrasound scanner. The acquired RF signals were processed and converted to a two-dimensional matrix M(i,j) (i.e., “file_name.mat”) where i represents the ith line of sight of the image (x axis) and j is the index of the time samples of each line of sight (y axis). The chosen “file_name.mat” can be defined as follows: “a_b_c.mat” where a stands for the dual-mode microbubble (MB) type that was analysed (i.e., MB-plain, MBN-into15, MBN-into38, and MBN-on29); b describes the imaging technique that was applied (CPS3 or Chirp CPS3); c represents the negative peak pressure at the focus depth (230 or 320 kPa). The ultrasound images were generated by processing the two-dimensional matrices by implementing the same functions as those used on the back end of the scanner system (i.e., envelope detection and logarithmic compression). Finally, the data can be used to calculate the contrast-to-tissue ratio (CTR), following the procedure described in the manuscript.

US_data.mat