Clinical question: Rule out structural cause for gait instability and nystagmus. Signs and symptoms: As above. Nonenhanced brain MRI:Diffusion-weighted images are severely limited due to extensive left-sided paramagnetic artifact obscuring significant portion of the hemisphere. Beyond the region of artifact no evidence of restricted diffusion. There is also partial effacement of the images on flair and susceptibility MRI series due to left-sided metallic artifact (patient known to have a shrapnel in the face).Examination demonstrates a tiny single focus of nonspecific flair hyperintensity in the right frontal centrum semiovale without enhancement. The finding has questionable clinical significance.The anatomical morphology and signal intensity to brain remains otherwise entirely within normal on all MRI sequences. Unremarkable cerebral cortex, cortical sulci, ventricular system, CSF spaces and brain myelination.The signal void of all major intracranial arterial branches are well visualized and unremarkable. The signal intensity of intracranial venous sinuses are beginning normal.Visualized calvarium and soft tissues of the scalp as well as orbits are unremarkable. Partially visualized paranasal sinuses demonstrate normal pneumatization signal pattern.
1.Metallic fragment/shrapnel in the left facial region results in diffuse artifact obscuring part of the left hemisphere as detailed.2.Within this limitation this examination is unremarkable. Please see above comments. If there are prior studies available and submitted to radiology department an addendum to this report could be submitted after comparison.