17-year-old male with relapsed ALL with recent CNS relapse: MRI evaluation prior to CAR T-cell therapy. There is persistent diffuse high T1 and T2 signal along the folia of the superior cerebellum, without appreciable abnormal enhancement. There is unchanged linear high T2 signal along a prior right transfrontal catheter track. There is no evidence of acute infarct. The ventricles and sulci are unchanged in size and configuration. There is a mega cisterna magna and partially-empty sella. There is no midline shift or herniation. The major cerebral flow voids are intact. The orbits, skull, and scalp soft tissues are unchanged. There is mild maxillary sinus mucosal thickening.
Persistent signal abnormality along the folia of the superior cerebellum likely represents treatment effects, without evidence of recurrent intracranial leukemia.