Syringomyelia

Question 1

What is syringomyelia?

Answer 1

A syrinx is a fluid-filled tubular cavity in or close to the central canal of the spinal cord

Question 2

What is the typical age of onset of synringomyelia?

Answer 2

30 years old

Question 3

What are causes of syringomyelia?

Answer 3

• Blocked CSF circulation
  
  • Arnold-chiari malformation
  • Basal arachnoiditis
  • Basilar invagination
  • Masses
• Following myelitis
• Following trauma
• Ruptured AV malformation
• Spinal tumours - fluid secretion from neoplastic cells

Question 4

What are symptoms of syringomyelia?

Answer 4

• Upper limb pain exacerbated by exertion/coughing
• Numbness
• Weakness

Question 5

What is Arnold-Chiari malformation?

Answer 5

Cerebellum herniates through foramen magnum

Question 6

What is basilar invagination?

Answer 6

Where the top of the odontoid peg migrates upwards, causing foramen magnum stenosis +/- medulla oblongata compression

Question 7

What are signs seen in syringomyelia?

Answer 7

• Suspended area of dissociated sensory loss
• Wasting/weakness of hands +/- claw hand spreading to arm -> shoulders-> respiratory muscles
• Horner’s syndrome
• UMN leg signs
• Body asymmetry
• Limb hemihypertrophy
• Unilateral hand/foot enlargement

Question 8

What is dissociated sensory loss?

Answer 8

Absent pain and Temperature sensation, with preserved light touch, vibration and proprioception

Question 9

Why do you get dissociated sensory loss in syringomyelia?

Answer 9

Due to pressure from the syrinx on the decussating anterolateral pathways in a root distribution reflecting the location of the syrinx (e.g. cervical syrinx causes sensory loss over trunk and arms)

Question 10

What is thought to causes unilateral large feet/hands, body asymmetry or limb hemihypertrophy in syrinomyelia?

Answer 10

Release of trophic factors via anterior horn cells

Question 11

What are features of syringobulbia?

Answer 11

Brainstem involvement

• Nystagmus
• Vertigo
• Bulbar palsy - Tongue atrophy/fasciculations, Dysphagia, Pharyngeal/palatal weakness, dysarthria, hoarseness
• Horner’s syndrome
• CNV palsy

Question 12

What investigation would you consider doing in someone with suspected syringomyelia?

Answer 12

MRI - shows syrinx

Question 13

How would you manage someone with syringomyelia?

Answer 13

• Surgical Decompression
  
  • ​Foramen magnum - Arnold-Chiari malformation - promote free flow of CSF