Overview
Syringomyelia is where there is a fluid-filled cyst (syrinx) in the central spinal cord, usually at the cervical level. The syrinx can enlarge and expand, compressing the nervous tissue in the corticospinal and spinothalamic tracts.
Syringobulbia is where a syrinx extends into the medulla (the bulb). This can lead to cranial nerve involvement.
Epidemiology
- More common in men than women
- Associated with Chiari I malformations
Risk Factors
- Can be idiopathic
- Trauma
- Disruptions of CSF circulation e.g. space-occupying lesions such as tumours
- Chiari I malformations
- Scoliosis
- Spina bifida
Presentation
Syringomyelia classically causes a loss of temperature sensation in the hands, back, and arms in a cape-like pattern.
Other features may be:
- Gait disturbances
- Cervical spine lesions can cause quadriplegia
- Thoracic spine lesions can cause paraplegia
- Tendon reflexes are usually increased below the level of injury, absent at the level, and normal above the level
- Neuropathic pain
- Autonomic dysfunction:
- Bladder/bowel/sexual dysfunction
- Horner’s syndrome
Investigations
- Spine MRI and brain MRI:
- Excludes tumours, Chiari malformations etc.
Management
- Asymptomatic – watch and wait
- Symptomatic – surgery
Complications and Progosis
Complications
- Loss of limb function and immobility
- Paraplegia/quadriplegia
- Bladder/bowel/sexual dysfunction
Prognosis
- Early intervention and management carry a better prognosis
- A syrinx very rarely regresses spontaneously
- Prognosis is worse if moderate-severe neurological complications are present
