Comparison with MRI

The pictures on the right show photo and MRI contrast images of a mouse with 2 implanted tumors. The second image shows a magnetic relaxometry spatial image either by itself (at left) or overlaid onto the anatomy of a mouse, clearly confirming the presence and localization of the 2 tumors. Finally, at the bottom, magnetic relaxometry images have been overlaid onto a mouse MRI image. Note that the MRI contrast image shows areas of accumulated contrast from nanoparticles not connected to cancer, while the relaxometry spatial images contain clearly defined positive signals that can be accurately located in space. We have further demonstrated that our method gives a linear signal based upon tumor cell number, whereas the MRI signal is non-linear.