Clinical question: Nodule of the left cerebellar lesion versus encephalomalacia. Signs and symptoms: Left-sided ataxia. Nonenhanced brain MRI:Diffusion weighted images demonstrate a focus of restricted diffusion consistent with an acute nonhemorrhagic ischemic stroke along the medial aspect of remaining left cerebellar hemisphere measuring at 31 x 11 mm in transaxial dimensions. As was noted on multiple prior exams there are bilateral paramedian encephalomalacia of bilateral cerebellar hemispheres (L>R) and with resultant mild expansion of fourth ventricle. Findings are believed to be at least partially secondary to a prior midline suboccipital craniectomy and with evidence of residual metallic density (surgical clips/coils?) in the midline similar to prior exam.Images through the supratentorial space demonstrate periventricular and to a lesser degree subcortical patchy foci of FLAIR/T2 hyperintensity suggestive of mild chronic small vessel ischemic strokes considering patient's stated age of 74. There is also prominence of of the supratentorial ventricular system with maintained midline and to a lesser degree prominence of the cortical sulci which although could be within normal range for patient of stated age possibility of mild underlying parenchymal volume loss should also be considered. A large focus of T2 hyperintensity extends from the lateral wall of left lateral ventricle superiorly to the inner table of the right frontal cortex believed to represent a focus of encephalomalacia along the track of a previously removed ventricular catheter. This finding is immediately under a right frontal calvarial burr hole.Unremarkable images through the orbits.Moderate right maxillary chronic sinus disease and well pneumatized other paranasal sinuses.Bilateral mastoid air cells and middle ear cavities demonstrate normal pneumatization signal pattern.
1.Diffusion-weighted images demonstrate a small acute nonhemorrhagic left cerebellar stroke measuring at 11 x 31 mm in transaxial dimensions.2.Bilateral (L>R) paramedian cerebellar encephalomalacia under a midline suboccipital craniectomy stable since multiple prior studies.3.Supratentorial images demonstrate mild chronic nonhemorrhagic small vessel ischemic strokes only in the subcortical and periventricular white matter.4.Prominence of the supratentorial ventricles and to a lesser degree cortical sulci for patient of stated age could be within upper limits of normal however possibility of underlying parenchymal volume loss should also be considered.