Related Subjects:
|Syringomyelia
|Syringobulbia
|Dandy Walker syndrome
Syringobulbia is a neurological condition characterized by the presence of a fluid-filled cavity, or syrinx, within the brainstem, specifically in the medulla oblongata. This condition is often associated with syringomyelia, where a similar syrinx forms within the spinal cord. Syringobulbia can lead to various neurological symptoms due to its location in the brainstem, affecting vital functions and cranial nerve nuclei.
About
- Syringobulbiarefers to a fluid-filled cavity (syrinx) within the brainstem, typically affecting the medulla oblongata. It is often associated with syringomyelia, a similar condition involving the spinal cord.
Aetiology
- Formation of a longitudinal cyst within the brainstem, usually the medulla oblongata.
- Frequently associated with blockage of cerebrospinal fluid (CSF) outflow from the fourth ventricle, often due to an Arnold-Chiari malformation(Chiari Type I).
- May occur as an extension of syringomyelia, where the syrinx begins in the spinal cord and ascends into the brainstem.
Causes
- Chiari Malformation:Congenital malformation where brain tissue extends into the spinal canal, leading to syrinx formation.
- Spinal Cord Injury:Trauma can cause syrinx formation in the spinal cord, which may extend into the brainstem.
- Intramedullary Tumours:Tumours in the spinal cord or brainstem can obstruct CSF flow, leading to syringobulbia.
- Post-Infectious or Post-Inflammatory Changes:Inflammatory or infectious conditions of the CNS can lead to the formation of a syrinx.
- Arachnoiditis:Inflammation of the arachnoid membrane, often following surgery, trauma, or infection, can obstruct CSF flow, resulting in syringobulbia.
Clinical Features
- Onion-skin distribution of sensory loss:Loss of pain and temperature sensation over the face, often sparing the nose, due to involvement of the trigeminal nerve.
- Facial pain:May occur along with sensory loss.
- Horner’s syndrome:Ptosis, miosis, and anhidrosis due to disruption of sympathetic pathways in the brainstem.
- Bulbar palsy:Dysphagia, dysarthria, and other symptoms due to cranial nerve IX, X, XI involvement.
- Cranial nerve palsies:
- Facial nerve (VII): Weakness or palsy of facial muscles.
- Glossopharyngeal and vagus nerves (IX, X): Impaired swallowing, hoarseness, or vocal cord palsy.
- Accessory nerve (XI): Weakness of the sternocleidomastoid and trapezius muscles.
- Hypoglossal nerve (XII): Wasting and fasciculations of the tongue.
- Cerebellar signs:Ataxia, dysmetria, and other signs of cerebellar involvement if connections are affected.
Investigations
- MRI:The imaging modality of choice to visualise the syrinx in the brainstem and assess its extent. MRI can also identify associated anomalies such as Chiari malformation.
- CT Scan:May be used if MRI is unavailable, though it is less sensitive in detecting syrinx cavities.
Management
- Conservative Management:In asymptomatic or mildly symptomatic cases, periodic monitoring with MRI is sufficient.
- Surgical Intervention:
- Decompression Surgery:Performed in cases of Chiari malformation to relieve pressure and improve CSF flow, which may help reduce the size of the syrinx.
- Syrinx Shunting:A surgical procedure where a shunt is placed to drain the syrinx, preventing further expansion.
- Tumour Resection:In cases where a tumour causes syringobulbia, surgical removal of the tumour may be required.
- Rehabilitation:Physical therapy (PT), occupational therapy (OT), and speech-language therapy (SLT) can help manage neurological deficits and improve quality of life.
- Symptomatic Treatment:Medications to manage pain, muscle spasticity, and other symptoms may be prescribed. Baclofen or gabapentin may be used for neuropathic pain.