Comparison of [18F]FDG and [68Ga]GaCl
imaging of the vasculature in mice. (a) CLI using [18F]FDG on a day-14 fibrosarcoma tumor with corresponding photographic image below. (b) CLI using [68Ga]GaCl3 for a day-14 fibrosarcoma tumor with corresponding photographic image below. The tumors are outlined in red. A blood vessel can be seen in the [18F]FDG image, resulting in a 6% reduction in radiance outside the tumor and 12% reduction in the tumor core. However, the vasculature is much clearer and more elaborate in the [68Ga]GaCl3 image, where the blood vessel in the tumor attenuated 9% of the Cerenkov light and the tumor core attenuated 18% of the Cerenkov light.