Clinical question: Metastatic lung cancer, prostate cancer, rule out brain metastases. Signs and symptoms: Cough. Pre- and post enhanced brain MRI:Unremarkable diffusion-weighted images.Examination demonstrates no detectable abnormal parenchymal, meningeal or calvarium enhancement to suggest metastatic disease.There are scattered punctate foci of FLAIR/T2 hyperintensity in bilateral subcortical and periventricular white matter and minimally in the bilateral basal ganglia and pons highly suggestive of mild chronic small vessel ischemic strokes.Unremarkable cerebral cortex, cortical sulci, ventricular system and CSF spaces otherwise.Examination demonstrates a focus of T2 hyperintense and T1 hypointense enhancing lesion in the left pterygoid muscle measuring at 12 x 17 mm in transaxial dimensions (axial enhanced series 1/4/2001 image 8 and sagittal post enhanced series 1/5/2001 image 9. Considering patient's history of malignancy finding is highly suspicious for focus of metastatic lesion.
1.No acute intracranial process.2.No detectable calvarium, leptomeningeal or parenchymal enhancement.3.Focus of signal abnormality and enhancement in the left pterygoid muscle measuring at 12-17 mm in transaxial dimensions with evidence of increased muscle size/edema which is suspected of a metastatic lesion. No prior exams for comparison.4.Negative diffusion weighted image and findings suggestive of mild chronic small vessel ischemic strokes as detailed.