 |  |  |
| T1 axial pre gad | T1 sagittal pre gad | T2 sagittal |
Diagnosis: Lipomyelomeningocele
Spinal lipomas consist of lipomyelomeningocele, filum terminale fibrolipoma, and intradural lipomas. Lipomyelomeningoceles make up 85% of all spinal lipomas. They consist of fat, meninges, and neural elements. Depending on the size of the lesion they may present anytime from infancy to adulthood with sensory problems, bladder dysfunction, or paraplegia. They are associated with spinal dysraphism and tether the cord resulting in a low lying conus. On MR the characteristic changes consist of an extradural fatty mass which is continuous with a low lying conus and the subcutaneous fat via a spinal dysraphism. Neural elements and meninges may appear within the subcutaneous portion of the lesion with signal heterogeneity at the dysraphism. The final terminale fibrolipoma represents 12% of spinal lipomas. They are small lipomas within the filum terminale at the tip of the conus and are incidental lesions on up to 5% of lumbar MR scans. Intradural lipomas represent 5% of spinal lipomas. They are intramedullary lesions most commonly seen in the cervical and thoracic spine at the dorsal aspect of the cord.
One interesting finding is this case is the dark signal outlining the ventral aspect of the lipoma. This is caused by the chemical shift artifact and is identified by a loss of signal at interfaces between fat and water containing structures due to the difference in Larmor frequencies of water versus fat. It is always perpendicular to the frequency encoding direction. Related Cases
