Fig. 2
From: Personalized radiation dosimetry for PRRT—how many scans are really required?
Examples of time activity concentration curves for tumors, showing a mono-exponential decrease; b bi-exponential, with initial steeper decrease over first 24 h approximately, followed by mono-exponential decrease; c initial increase over first 24 h approximately, followed by mono-exponential decrease. Note that in all these graphs, tumors are labelled 1, 2, and 3 only to distinguish the curves from each other, and there is no significance to the numbering