Fact-sheet: Lipoma of filum terminale
Updated on 03/31/2026 at 1:42 PM
View all RADEOS cases associated with this fact-sheet
Definition
Rare benign condition belonging to the closed dysraphisms, related to a disorder of mesodermal cell migration
Category of spinal lipoma along with intradural lipomas and lipomyelomeningoceles
Frequently associated with developmental abnormalities: low tethered cord (>L2), syringomyelia, hydromyelia.
Clinical features
- Most often asymptomatic
- If symptomatic: symptoms of tethered cord
- When located at the thoracic level, it can cause chronic thoracolumbar back pain and headaches (due to increased intradural pressure)
- Cauda equina syndrome, conus medullaris compression
CT
Possible associated bony malformations
Fat-density lesion
MRI
MRI is the imaging modality of choice:
- Fatty lesion, linear or band-like, hyperintense on T1
- Extramedullary, limited to the intradural or extradural portion of the filum, or possibly involving both portions
- Hypointense on fat-saturated sequences
- No enhancement after gadolinium injection
Allows precise assessment of the relationship with the conus medullaris and the nerve roots.
Look for an associated tethered cord and/or thickening of the filum terminale
Management
As a rule, incidental finding and no treatment required.
Otherwise, surgical management: decompressive laminectomy and resection of the tumoral lesion (usually incomplete due to nerve root encasement)
Differential diagnosis
Dermoid tumor
Teratomatous tumor
