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Scaled cortical contusions in piglets demonstrated age-dependent differences in injury response, both in magnitude and time course. These observations may shed light on development-related trauma response in the gyrencephalic brain.

Energy and spatial projection distributions were simulated for gamma camera imaging of multiple order Compton scattered photons. SPECT imaging of a line source of radioactivity located in a water filled cylindrical phantom was modelled using Monte Carlo techniques. Photon trajectories were followed from emission to detection including the effects of all physical interactions and the resulting energy spectra and spatial projections were sorted as a function of the number of times the photon underwent Compton scattering before detection. Analysis of energy spectra demonstrates that Compton events up to second order overlap with the non-scattered events and distributions are peaked at lower energies as the scattering order increases. Analysis of spatial projections shows that, with increasing order, Compton events produce tails on the line spread function which progress from roughly exponential to nearly flat distributions. The use of Monte Carlo modelling thus allows a detailed investigation of the spatial and energy distribution of Compton scatter which could not be performed using present experimental techniques. ZusammenfassungEnergieverteilung und raumliche Verteilung der Mehrfach-Comptonstreuung beim SPECT: eine Monte Carlo-Untersuchung.Verteilungen der Energie und der raumlichen Projektionen wurden simuliert fur Gammakamera-Abbildungen von mehrfach Compton-gestreuten Photonen. SPECT-Abbildungen einer radioaktiven Linienquelle in einem