Legend A large, heterogeneous intra-axial mass is seen in the left posterior parietal lobe with internal septations, cystic and solid components. There is surrounding edema and local mass effect without significant midline shift. Multiple ovoid and punctate foci of periventricular and subcortical T2/FLAIR hyperintensities are present.

Legend Post-contrast images demonstrates enhancing rim of the mass with internal enhancing linear and nodular areas.

Legend Sagittal FLAIR image demonstrates pericallosal ovoid and "finger-like" white matter hyperintense foci, suspicious for a demyelinating process. MR spectroscopy demonstrates elevated choline in regions of nodular enhancement suspicious for tumor, and elevated lipids centrally, which may represent necrosis.

Legend MR perfusion demonstrates increased rCBV in the left posterior parietal lobe corresponding to the suspicious mass. Key words: mri neoplasia tumor demyelinating mrs perfusion pwi

Brain Diagnosis: 1. Metastasis - Adenocarcinoma of lung 2. Chronic multiple sclerosis