Figure 10.

Triple-modality detection of brain tumors in living mice with integrated nanoparticles. Three weeks after orthotopic inoculation, tumor-bearing mice (n = 4) were injected intravenously with the NPs. Photoacoustic, Raman, and MRI images of the brain (skin and skull intact) were acquired before and 2 h, 3 h, and 4 h after injection, respectively. (A) 2D axial MRI, photoacoustic, and Raman images. The post-injection images of all three modalities demonstrated clear tumor visualization. The photoacoustic and Raman images were co-registered with the MR image, demonstrating good co-localization between the three modalities. (B) 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 co-localization of the photoacoustic signal with the tumor. (C) Quantification of signal in the tumor shows significant increase in MRI, photoacoustic and Raman signals before versus after the injection (*** indicates P < 0.001, ** indicates P < 0.01). Adapted by permission from Macmillan Publishers Ltd: [Nature Medicine]¹⁸⁵, copyright (2012).