55 years, Female, altered mental status, tremors, cranial nerve deficits, evaluate for paraneoplastic disease. Examination is moderately motion degraded. No restricted diffusion to suggest acute ischemia. No intracranial hemorrhage. No intracranial mass or mass-effect. The ventricles are within normal limits in size and configuration. Few scattered foci of T2/FLAIR hyperintensity are seen in the bilateral subcortical and periventricular white matter, which are nonspecific, but compatible with mild chronic small vessel ischemic changes. Borderline low cerebellar tonsils again seen. Brain parenchyma is otherwise unremarkable for age. Minimal mucosal thickening in the paranasal sinuses. Incidentally noted is absent nasal septum and partial absence of the inferior turbinates as seen on recent CT. Major flow-voids are preserved. Bone marrow signal and extracranial soft tissues are otherwise unremarkable.
1. Examination is motion degraded. Within this limitation, there is no evidence of acute infarct, intracranial mass or mass effect, or parenchymal signal abnormality to suggest encephalitis. Absence of gadolinium limits evaluation for leptomeningeal disease and cranial nerve involvement as mentioned in the history; lumbar puncture can be considered as clinically indicated. 2. Absence of the nasal septum and small turbinates may be related to prior surgery, granulomatous disease, or given history of substance abuse, can be seen with cocaine use.