Neuroradiology

Fibrolipoma, of the filum terminale

small collections of fat tissue located along either the intra, or the extra or both portions of the filum terminale. They are embryonic in origin and are believed to derive from a minor disruption in the process of canalization and retrogressive differentiation, the precise nature of which is unclear. They have been reported in up to 6% of consecutive autopsy series and in up to 67% of cases with associated myelomeningocele. The estimated relative incidence of 12% reported in series of spinal lipomas is probably underestimated as this type of lesion is frequently asymptomatic. Tethering of the cord may be an accompaniment to a fibrolipoma of the filum terminale, especially in larger lesions, but it is fairly infrequent.

FS