Clinical question: Evaluate for cerebellar brain metastases, concern for CNS progression of disease. Signs and symptoms: Vertigo. Pre-and post-enhanced brain MRI:Negative diffusion weighted series.Examination demonstrates a thick irregular rim enhancing mass in the left cerebellum measuring approximately a 29 x 20.5-mm and consistent with patient's previously known metastatic lesion.This lesion demonstrated no significant enhancement on prior study. On nonenhanced exam there is no significant change in the size of this lesion. There is slight interval decreased surrounding vasogenic edema. The fourth ventricle remains reading normal and in midline similar to prior study. There is no detectable additional foci of enhancement in the posterior fossa.Images through supratentorial space remains negative for parenchymal or leptomeningeal metastases.Ventricle are patent the lesser degree subcortical foci of there and T2 hyperintensity is less conspicuous on current exam compared to prior which may be due to technique difference of 3T scan on prior exam and 1.5 on current. Examination also mildly degraded due to motion artifact on flair sequence. Focus of encephalomalacia in the left occipital lobe without abnormal enhancement remains similar to prior exam. Prominence of cortical sulci similar to prior study. Stable normal size of ventricular system and without deviation of midline.
1.No significant change in the size of a previously known metastatic lesion in the left cerebellum. In comparison to prior exam however this lesion demonstrate intense irregular rim enhancement which was not present on prior study and could be as result of change in treatment regimen/medication. Subtle regional mass effect of this lesion remains identical to prior study.2.No detectable additional metastatic lesions.3.Stable focus of encephalomalacia without enhancement in the left occipital lobe since prior study.