Figure 5.

A unique triple-modality magnetic resonance imaging-photoacoustic imaging-Raman imaging (MPR) nanoparticle for selective multimodal imaging of tumor margins in glioblastoma-bearing mice. (a) Triple-modality MPR concept; (b, c) three weeks after orthotopic inoculation, tumor-bearing mice (n = 4) were injected intravenously with MPRs (16 nm, 170 μl). Photoacoustic, Raman, and MR images of the brain (skin and skull intact) were acquired before and 2 h, 3 h, and 4 h after injection, respectively. (b) 2D axial MRI, photoacoustic, and Raman images. The postinjection images of all three modalities demonstrated clear tumor visualization. The photoacoustic and Raman images were coregistered with the MR image, demonstrating good colocalization between the three modalities. (c) 3D rendering of MR images with the tumor segmented (red; top); overlay of 3D photoacoustic images (green) over MRI (middle); and overlay of MRI, segmented tumor, and photoacoustic image (bottom) showing good colocalization of the photoacoustic signal with the tumor. Reprinted with permission from Ref. [83].