Radiology Quiz 19504 | Radiopaedia.org

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Questions
Findings

What do you think of the intradural compartment as seen on sagittal T1 C+ images?

There is an apparent region of enhancement which should make you concerned of CSF seeding.

What do you think causes this appearance?

If you look at the pre contrast T1 sagittal and axial images it appears that this is due to bulging epidural fat, narrowing the theca (epidural lipomatosis) and pushing the nerve roots together. No convincing intradural mass can be identified.

Question 3

How could you confirm this to be the case?

Show Answer

A fat saturated post contrast sagittal sequence would be the easiest way to confim this, as the partially volumed epidural fat would be saturated and therefor not visible, whereas a mass would persist. High resolution thin axial T2 weighted images would also be able to show the nerve roots pushed together but otherwise unremarkable at this level.

This patient's symptoms had been gradual and progressive. There was no history of preceding infection or illness, and CSF was bland. The lesion did not resolve on follow up imaging and a biopsy of the conus confirmed a diffuse WHO II astrocytoma.