Page 335 - Medicine and Surgery

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Chapter 7: Disorders of the spinal cord 331

Syringomyelia and syringobulbia Management
Decompression of the foramen magnum, aspiration of
Definition
the syrinx, sometimes with placement of a shunt may
Asyrinx is a fluid filled slit like cavity developing in the
halt progression.
spinal cord (syringomyelia) or the brain stem (syringob-
ulbia).
Prognosis
Condition is intermittently progressive over a number
Age
of decades.
Usually presents aged 20–40 years.
Sex Transverse myelitis
M = F
Definition
Acute inflammation of the spinal cord.
Aetiology
The cavity or syrinx is in continuity with the central
Aetiology
canal of the spinal cord. It is associated with a history
Causes include syphilis, viral and mycoplasma infec-
of birth injury, bony abnormalities at the foramen mag-
tions, multiple sclerosis, systemic lupus erythematosus
num, spina bifida, Arnold–Chiari malformation (herni-
and post-radiation therapy. Some cases have been re-
ation of the cerebellar tonsils and medulla through the
ported post-vaccination. Many cases are idiopathic.
foramen magnum) or hydrocephalus.
Pathophysiology
Pathophysiology
Inflammation may be due to vasculitis, or the preceding
The expanding cavity may destroy spinothalamic neu-
infection. There is oedema of the cord, which causes
rones in the cervical cord, anterior horn cells and lateral
upper motor neurone signs below the level of the lesion,
corticospinal tracts.
usually a paraparesis, and sensory loss up to the level of
the lesion. Sphincter dysfunction may occur.
Clinical features
Mixedupper and motor neurone signs, sometimes in an
odd distribution, it is usually bilateral, but may affect Clinical features
one side more than the other. Spinal shock, i.e. a flaccid weakness may initially occur,
Syringomyelia: There is typically wasting of the in-
which then becomes a spastic paraparesis. The patient
trinsic muscles of the hand, with loss of upper limb may complain of a tight band around the chest, which
reflexes and spastic weakness in the legs. The sensory may suggest the level of the lesion. Upper motor neurone
changes are loss of pain and temperature sensation signs are found below the lesion. Occasionally lower mo-
in the affected levels, e.g. C5 to T1 with preservation torneurone signs are found at the level of the lesion, due
of touch. Neuropathic joints, neuropathic ulcers and to involvementof the anterior horn cells.
accidental trauma and burns may result.
Syringobulbia: When the cavity extends into the brain
Investigations
stem the lower cranial nerves are affected – the tongue MRI may show oedema and excludes a space-occupying
is atrophied and fasciculates, there may be nystagmus, lesion. CSF may be normal, or show increased protein
dysarthria, Horner’s syndrome. Involvement of the content and pleocytosis. Other investigations are di-
fifth nerve nuclei causes loss of facial sensation, classi- rected at the underlying cause, e.g. syphilis serology, my-
th
cally in a circumferential pattern, and the VIII nerve coplasma titres, anti-dsDNA (for SLE).
nucleus may be affected causing hearing loss.
Management
Investigations Steroids may be used, once infection has been ex-
Diagnosed by CT or MRI scanning. cluded, to speed recovery. Vasculitis may need aggressive