Summary: A 10-year-old boy with a known history of Hunter syndrome and a history
of spastic quadriplegia presented with worsening paresthesias and
dysesthesias in both hands. Magnetic resonance imaging (MRI) of the
cervical spine was performed without contrast.
MRI of the cervical spine without contrast was available for review. The
cervical spinal cord demonstrated moderate enlargement from the foramen
magnum to C7, with a maximum caliber of 9 mm. Minimal diffuse T2
prolongation (Figure 1) was seen in the enlarged region without evidence
of a focal mass or syrinx. The T1 signal (Figure 2) was normal. There
was no evidence of an intradural, extramedullary lesion, or meningeal
thickening. The thoracic cord was normal in caliber and signal,
measuring 5 mm. The cervical spine (Figure 3) was normally aligned, and
the dens was hypoplastic. Soft tissues posterior to the dens were
prominent (Figure 4), measuring 3 mm in thickness and causing
mild-to-moderate narrowing of the foramen magnum. Visualization of the
brain (Figure 5) was limited to the inferior portions of the temporal
and occipital lobes, but ventriculomegaly was noted, as was diffuse T2
prolongation throughout the visualized portions of white matter.
Hunter syndrome is a genetic disorder classified as one of the
lysosomal storage diseases, specifically mucopolysaccharidosis II. The
buildup of glycosaminoglycans in the cells leads to symptoms early in
life, generally in the first few years. The clinical features include
macrocrania, distinct facial features, and usually developmental delay
owing to the CNS involvement. Hepatosplenomegaly, joint problems, and
airway compromise are also seen.1 Although typical clinical
features are seen in the first few years of life, the diagnosis is made
biochemically or with genetic testing.
findings are not specific, and they are commonly quite similar among the
mucopolysaccharidoses. Although not necessarily useful diagnostically,
imaging is suggestive, and may be used (as in this case) to evaluate a
patient with changing neurologic symptoms.
macrocrania, dilated perivascular spaces, cystic spaces in the white
matter, communicating hydrocephalus, and delayed myelination. Areas of
T2 prolongation are therefore seen in the white matter.1 Thickening of the dura is noted as the cause of cervical spondylopathy in several cases in the literature.2-5
A search of Medline from 1966 to the present with the search words
Hunter, mucopolysaccharidosis, thickening, cervical, and/or cord did not
yield reports of cervical cord thickening in patients with Hurler
Given that all cells have lysosomes, and that white
matter involvement in the brain has been widely reported, it seems at
least plausible that the cervical cord thickening seen in this patient
is secondary to deposition of the mucopolysaccharide. Other diagnostic
possibilities include astrocytoma, although this or other neoplastic
processes would not likely have such a homogeneous appearance. In any
case, biopsy of the cord was not performed.
In cases of cervical stenosis secondary to dural thickening, the treatment may include laminectomy and occipital craniotomy.2
In summary, Hunter syndrome is an uncommon mucopolysaccharidosis
that frequently presents in early childhood with multisystem
involvement. Typically, the cervical myelopathy has been attributed to
extrinsic compression of the cord by thickened meninges. In the patient
in question, dural thickening is not noted, but the presence of cervical
cord thickening and T2 hyperintensity lead us to speculate that in this
case the myelopathy is at least in part secondary to infiltration with
- Grossman, Robert I, Yoursem, David M. In: Neuroradiology: The Requisites. 2003. Philadelphia, PA, Elsevier.
- Kaendler S, Bockenheimer S, Grafin Vitzthum, H. Galow, W. Cervical
myelopathy in mucopolysaccharidosis type II (Hunter’s Syndrome).
Neuroradiologic, clinical and histopathologic findings (translated). Deutsche Medizinische Wohenschrift. 115:1348-1352.
- Ballenger, C E. Swift, T R. Leshner, R T. et al. Myelopathy in mucopolysaccharidosis type II (Hunter’s Syndrome). Annals of Neurology. 1980:7:382-385.
- Vinchon, M. Cotton, A. Clarisse, J. et al. Cervical myelopathy secondary to Hunter syndrome in an adult. AJNR Am J Neuroradiol. 1995;16:1402-1403.
- Koyama, K. Moda, Y. Sone, A. et al. Neurogenic bladder in Hunter’s syndrome. J Med Genetics. 1994; 31:257-258.