Figure 5a, b presents the fluorescence signal intensity from contralateral normal brain as a function of the tumor area detected by the lowest and highest dose of the pre-GMP ABY-029. There are no statistically significant fluorescence trends for tumor size in the 1× microdose group; however, there is a significance when the dose is elevated fivefold.Fig. 5.Fluorescence from the contralateral normal brain as a function of the observed tumor size for a microdose (24.5 μg/kg) and b five times the microdose (122.5 μg/kg); 1 h (closed symbols) and 24 h (open symbols) post-injection. The lines correspond significant trends observed from linear regression. c T1 (left) and T2 (right) MRI of a U251 tumor-bearing rat post-gadolinium injection. The tumor (T) can be seen as a focal region in the T1, with peri-tumor edema (E) in the T2 image.