Performance characterization.

<p>FDG aggregates were obtained by evaporating an aqueous solution of FDG between a scintillator and a glass-bottom imaging dish. (<b>A</b>) Fused radioluminescence and brightfield images; (<b>B</b>) Brightfield and (<b>C</b>) radioluminescence images, magnified; (<b>D</b>) Brightfield and (<b>E</b>) radioluminescence images, further magnified, focusing on one particular FDG aggregate; (<b>F</b>,<b>G</b>) 2-D Gaussian fit of (D) and (E), respectively. (<b>H</b>) Radioluminescence microscope sensitivity, obtained by imaging the decay of a drop of FDG (2.6 µCi) over time. <i>Solid line</i>: mean pixel intensity; <i>Dashed line</i>: ideal exponential decay for ¹⁸F. (<b>I</b>) Per-pixel signal-to-noise ratio, defined as the ratio of the average pixel intensity to the noise standard deviation. The sensitivity of the system is defined here as the amount of activity required per area to achieve a SNR of 5 (Rose criterion ).