There is an extensive high T2 and FLAIR signal abnormalities surrounding the resection cavity and extending superiorly throughout the frontoparietal white matter, as well as a thick linear and irregular contrast enhancement along the resection margins in the temporal lobe occupying the resection cavity. No areas of restricted diffusion; in fact there is strikingly facilitated diffusion. These findings are unchanged compared to the most recent scan, however, are increased compared to the post-operative scan.
Spectroscopy traces reveal increased choline just within the transition of the enhancing margins to the adjacent brain parenchyma; elsewhere the trace is essentially hypometabolic with a dominant lactate peak.
There are just a few scattered foci of increased perfusion, likely vascular. The enhancing component demonstrates low CBV.
Conclusion: Although residual tumour no doubt is present, in this treatment context, the features suggest pseudoprogression as the dominant process.