Fatty infiltration of filum terminalle

My 15 year old daughter’s full spine MRI said she has fatty infiltration if the fillum terminalle…does anyone know What this means? She has 10mm herniation with slight disruption of csf flow.

Fatty filum terminale is one of the most common findings on lumbar MRI in the Chiari patient population.

Here is another Chiari web site with more data


In general, fatty filum terminale=surgery in any patient who is still growing or any symptomatic patient. Embryologically the skin and the central nervous system come from the same series of cells, so this is normal fat, meant to be under the skin, that got suck to the spinal cord(tethered cord). Sectioning of the filum terminale is a much smaller operation that a Chiari decompression and would certainly need to be addressed before any other surgical option. The fat does not stretch to the same degree the nerves do so the cord is tethered(pulled down).

If this is an incidental finding in an otherwise asymptomatic adult, it can be safely watched as 50% of patients with fatty filum terminale are asymptomatic(as compared to 80% of patients with Chiari being asymptomatic, meaning fatty filum causes symptoms much more frequently than Chiari).

That is really an individual issue and depends on the child and images.

In general, picture the spinal cord as being less elastic than it should be, so anything that stretches the spinal cord may cause damage(until cleared).

There is a list of neurosurgeons with Chiari interest listed on this web site. Also, board certified pediatric neurosurgeons can be found at www.abpns.org Those would probably be reasonable starting points.

Sorry, that's too broad a question for me to reliably answer. Thecal sac where? Brain stem? Lumbar?

In general, thecal sac deviation is evidence of local pressure.

All the deformity of the ventral thecal sac is revealing is the disc protrusion(the disc is anterior "ventral" to the thecal sac and therefore pushes the sac posteriorly). that is just a radiology way of saying it is not pressing on any nerve roots that they can see, only CSF.

It has nothing directly to do with Chiari or tethered cord(although many chiari patients also have connective tissue diseases, of which EDS is one of the trendier diagnoses, and a connective tissue disorder would cause ligamentous laxity, which would increase the risk of a disc protrusion).

The question re EDS is really more a rheumatological question than a neurosurgical question but, yes, there are multiple types and vascular EDS is different than the one usually related to Chiari.