Fig. 8 Three-dimensional reconstructions of the tracer distribution in Column 4 obtained by SPECT scanning. The reconstructions represent 3-D tracer distribution at different times after injection: (a) 2 min, (b) 4 min, (c) 6 min, (d) 8 min, (e) 10 min, (f) 12 min, (g) 14 min, (h) 16 min, and (i) 18 min