Fig. 7

Simulated data: a estimated \(\textrm{FWHM}_{xyz}\) for 10–1000 MLEM iterations for the global \(h_{pts}\), \(h_{PVC}\) and \(h_{AFC}\) kernels determined from the six VOIs combined; b RMSE of the AF-corrected whole lung (\(\rho\) = 0.024 ± 0.018 g.\(\hbox {cm}^{-3}\)) when the mu-map was smoothed by a global kernel derived from the six VOIs combined (dots), and kernels derived from individual VOIs (shaded regions depict range across six VOIs) at 10–1000 MLEM iterations