 MRI brain: A right frontal approach ventricular catheter again terminates in the inferior aspect of the right lateral ventricle, near the foramen of Monro.The prior leptomeningeal enhancement involving the sulci of the left occipital and temporal lobes has improved with only trace residual enhancement seen at these locations and elsewhere. There is also interval improvement of dural thickening and enhancement along the left temporal and occipital convexities. A thin line of apparent enhancement is seen running along the posterior upper spinal cord precisely at midline. This finding was not present on prior examinations, and it is unclear if it represents a pathologic process or simply a vascular phenomenon.There has been significant interval increase in the periventricular and subcortical white matter T2 FLAIR hyperintensity, likely related to treatment effects. There is no intracranial mass effect, midline shift, or herniation. Ventricles are not significantly changed in size since prior. There is again heterogeneity of the bone marrow which is nonspecific.MRI orbits: There is increased T2/FLAIR signal and enhancement along the optic nerve sheaths, right more so than left. No abnormal enhancement is evident in the right optic nerve. The left optic nerve is normal in size and signal intensity. No discrete retrobulbar mass, chiasmatic mass, or parasellar abnormality is seen. Extraocular muscles are unremarkable.
1. Improved leptomeningeal enhancement with mild residual abnormal enhancement in the brain.2. A thin line of apparent enhancement is evident running along the dorsal aspect of the visualized spinal cord at midline. The significance of this finding is unclear as it may reflect true pathology or simply a vascular phenomenon. Attention on subsequent exams is suggested, and dedicated spine imaging can be considered if clinically warranted.3. Progressive white matter signal abnormality, probably related to treatment changes.4. Prior enhancement of the right optic nerve has resolved. Abnormally increased T2 signal and enhancement around the optic nerve sheaths, right more so than left, has developed and could be related to disease involvement of the nerve sheaths.