Magnetic Nanoplatelets for High Contrast Cardiovascular Imaging by Magnetically Modulated Optical Coherence Tomography

Improving clinical techniques for cardiovascular imaging is important for better diagnosis / treatment of cardiovascular diseases, a main cause of mortality in western countries. One problem is a lack of contrast and hence the difficult interpretation of intracoronary images, especially those achieved by optical techniques, such as intracoronary optical coherence tomography (IC‐OCT). This could be overcome by multifunctional contrast agents, leading to better interpretability. In this work, magnetic nanoplatelets are employed to increase the contrast of IC‐OCT images by means of a magnetically modulated approach. This allows high‐resolution visualization of individual macrophages by IC‐OCT, fundamental in the formation of arteriosclerosis plaques. In addition, it is demonstrated that the nanoplatelets and nanoplatelets‐marked‐macrophages can be magnetically driven to specific sites. Thus, the results herein identify magnetic nanoplatelets as unique contrast agents for high‐resolution cardiovascular imaging by optical coherence tomography. Watch and learn: Optomagnetic barium ferrite nanoparticles can act as a bimodal contrast agent in optical coherence tomography (OCT) and magnetic resonance imaging of the cardiovascular system. Furthermore, they add the capacity for dynamic high contrast imaging to OCT when external magnetic fields are applied, allowing a Fourier domain analysis of the obtained images.