MRI, Perfusion and PET scan in a Patient Presenting a Brain Tumor

To illustrate the functionalities of BrainMagix, Imagilys's neuroimaging software, we study the case of a 32-year old male patient presenting a right temporo-parieto-occipital glioma.

Methionine PET demonstrated a large area of methionine uptake with a hot spot in the infero-posterior area of the tumor, indicating a high grade component. This zone was manually outlined, and the region of interest (ROI) was superimposed on T1- and T2-weighted MR images (Fig. 1) Fig. 1: ROI defined on the methionine PET superimposed on T1 and T2 MR images. .

Fig. 2: The hottest spot as defined on MR perfusion (red/yellow) and methionine PET (blue), superimposed on the T2 MRI. Perfusion MRI showed a very high rCBV, 14 times higher in the hotspot than in the normal contra-lateral tissue. The hottest spots as defined by PET and MR perfusion imaging were compared (Fig. 2). The results display partial overlap, but the perfusion hot spot is more anterior.

Fig. 3: Intra-operative FLAIR showed a complete resection at this level. Brain shift can be observed. Intra-operative MRI (iMRI) was performed during the tumor resection. FLAIR showed a complete resection of the tumor on the slice depicted in Fig. 3. However, the brain shift during the surgical procedure makes a comparison with the pre-operative tumor delineation more complex. In the inferior part of the original tumor, intra-operative FLAIR indicates possible residual tumor as dark areas medial to the cavity (Fig. 4 middle). The resection had been completed after iMRI as shown in the T2 image of Fig. 4. Histological analysis revealed an anaplasic astrocytoma. Fig. 4. Pre-operative T1, intra-operative FLAIR with potential residual tumor seen as gray areas in the edema. Post-operative T2 indicated the complete resection of the tumor.