Figure 2. Longitudinal imaging of a TAg-RB tumor with OCT. A single, representative eye imaged weekly from 2 to 12 weeks of age as indicated shows early clusters of presumptive T-antigen (TAg)-positive cells decreasing around 4 weeks, as previously observed with immunohistochemistry. Then, a distinct tumor mass is first evident at 5 weeks and grows over subsequent weeks. Retinal blood vessels (seen by their shadow) sit adjacent to this small tumor during weeks 6–7 and atop the tumor from week 8. Optical coherence tomography (OCT) scale bars=100 µm.