2 yr. old w/ syrinx, spina bifida occult

[fiddleplayer]

Scans from 5/05 show my two year old has two small syrinxes C4-C7 and T3-T8 (2mm). He also has spina bifida occulta. Not sure if he has a tethered cord. I’ve read that you can have a tethered cord even if it terminates at L1.  He has visible leg weakness causing his right leg to buckle. He drags his right foot frequently. His feet turn out, and he falls a lot. He complains that his back hurts and that his eyes hurt (headache?).  He was diagnosed at birth (4/03) with a Malignant Rhabdoid Tumor and received chemotherapy for 9 months including intrathecal methotrexate. The tumor was just outside of his spine, right where the thoracic syrinx is.  Diagnosing the leg weakness and related issues was complicated because the doctors thought he had peripheral neuropathy from Vincristine. We have not yet seen a neurosurgeon (appt. 9-8-05), and I am looking for information about spina bifida occulta, tethered cords, and syrinxes. The neurosurgeon’s nurse said that a 2 mm syrinx wouldn’t cause these problems.  What do you think?  What does “prominent CSF pulsation artifact noted around the cord” mean?  Are there other things we should be looking at?  How often should we scan to see if the syrinxes have increased in size?  I want to know how persistent to be with the doctors.  Since he has obvious problems with his gait, is surgical intervention necessary to prevent further neurological damage?

Here is a copy of his MRI report.

Cervical spine:  The spinal canal, neural foramina and posterior disk margins are unremarkable.  There is a linear area of increased T2 signal within the central cord at C4-C7 consistent with a minimal syrinx or slightly prominent central canal.  No other abnormal cord signal or enhancement is identified.  The cerebellar tonsils lie in a normal location.  There is some prominent CSF pulsation artifact noted around the cord.

Thoracic spine:  The spinal canal, neural foramina and posterior disk margins are unremarkable.  There is a small cord syrinx extending from approximately T3-T8 with a maximum diameter of 1-2 mm.  There is no abnormal enhancement.  Some normal CSF pulsation artifact is noted around the cord.  The conus is normal and terminates at L1.

Lumbar spine:  The spinal canal, neural foramina and posterior disk margins are unremarkable.  No abnormal enhancement is seen.

Brain:  Precontrast scans demonstrate some stable, mildly asymmetric lateral ventricles consistent with a normal variant.  Some mild FLAIR signal in the parietal white matter can be attributed to normal variation which is unchanged.  There is no new or significant abnormal signal, restriction diffusion, hemorrhage or extraaxial fluid collection.  Post contrast scans demonstrate no abnormal enhancement, mass or vascular abnormality.  The skull base and extranial structures are normal.

[CCF-Neuro-M.D.-PW]

The flow of CSF in a non-linear way around the spinal cord produces a change in the signal used to produce the MRI image - so it shows up as an apparent 'abnormality' but is really just CSF flowing around that region. If 'prominent' the flow may be caused by a turbulence around an abnormal area but this is hard to prove unless a strucutral abnormality is present. It is hard for me to be specific without looking at the actual scans.

A 2mm syrinx is pretty small but it may not be the only abnormality present - for example, there may be adhesions or chronic arachnoisitis (inflammation of the lining of the spinal cord) realte to the methotrexate. This may be invisible on MRI also. Syrinxes are commonly due to trauma, tumor or a congenital abnormality. I'm not sure if your can be explained by the local tumor/chemo but in most cases they remain static. Perhaps a repeat scan every 6 months at least initially to make sure it i snot expanding. I am not an expert in this area, though so you should pursue an expert opinion. A thethered cord should be apparent on MRI also - perhaps a second opinion of the MRI would be a good idea. Try the eCleveland Clinic radiology consult site. I cannot seperate over the internet the cause of his leg problems - thethered cord, myelopathy, peripheral neuropathy, chronic arachnoisitis. An EMG and nerve conduction studies could help differentiate a peipheral neuropathy from chemo from a spinal cord problem.

Good luck