Fig. 8.

Pseudoprogression. A 46-year-old male with left callosal/pericallosal glioblastoma multiforme. Initial post-resection MRI demonstrates a small area of irregular enhancement along the anterior margin of the resection cavity (arrow). Follow-up imaging obtained 4 months later (2 months after completion of radiation) demonstrates a significant increase in peripheral, now thick, fluffy enhancement along the resection cavity, most marked posteriorly (bracket). Repeat MRI obtained 8 months post resection demonstrates decreased enhancement (arrowhead). No appreciable elevated perfusion or diffusion restriction was present (not shown). The constellation of findings is compatible with pseudoprogression on the 4-month postoperative scan