Case Notes
History
61 yo male who presented at outside hospital with a possible lumbar abscess; Rx with antipiotics. Imaging revealed hydrocephalus and lumbar arachnoiditis and subacute meningitisExam
MR diffusion
Prior Study
Axial noncontrast head CT1. Bilateral symmetric cerebellar edema producing obstructive hydrocephalus and moderate upward transtentorial herniation. The basis for the cerebellar swelling is indeterminate without additonal MR sequences including a post contrast T1-w study.
2. There is grade 1.6/4 obstructive hydrocephalus.
3. Elevated CSF pressure has produced optic hydrops
Sagittal post contrast T1-w MR
1. Status post ventriculostomy placement with significant reduction in ventricular size (now grade 1.2/4).
2. Persistent, possibly increased central, upward, transtentorial herniation.
3. Persistent cerebellar edema without intercurrent hemorrhage.
MR flair
1. Diffuse subpial edema and early CSF protein leak consistent with hyperacute to acute phase (1-3 days) leptomeningitis. The edema is most apparent in the cerebellar hemispheres, accounting for the cerebellar swelling.
2. Improved ventricular size follow ventriculostomy placement, as above. There is some post ventriculostomy intraventricular blood products.
Post contrast axial T1-w MR
1. Pial and subpial hyperemia consistent with active leptomeningitis. There is no parenchymal enhancement to suggest intercurrent cerebritis or tissue necrosis.
2. Status post right ventriculostomy with minimal intraventricular blood products, as above.
MR susceptibility
1. Status post right ventriculostomy placement with minimal blood products along the tube tract and within the ventricles.
2. There is suspicion of caudal cerebellar hemorrhagic necrosis; findings are not definitive.