What is the best approach to treating syringomyelia?

Best Approach to Syringomyelia

For symptomatic Chiari malformation-associated syringomyelia (the most common type), perform posterior fossa decompression with or without duraplasty as first-line treatment, targeting the underlying cause rather than the syrinx itself. 1, 2

Initial Diagnostic Workup

• Obtain complete MRI imaging of the entire brain AND spine, not just the symptomatic region, as syringes frequently extend beyond initially imaged areas and you must identify the underlying cause 1, 2
• Specifically evaluate for Chiari malformation (present in 25-50% of syringomyelia cases), hydrocephalus, tethered cord, and any extramedullary compressive lesions 2
• Include T1, T2-weighted sequences, FLAIR, T2*-weighted gradient echo, pre/post-contrast T1, and high-resolution heavily T2-weighted 3D sequences 2
• In adolescents presenting with scoliosis, maintain high suspicion as 2-4% harbor underlying syringomyelia 2

Treatment Algorithm Based on Etiology

Chiari Malformation-Associated (Most Common)

• Perform posterior fossa decompression (PFD) alone or PFD with duraplasty (PFDD) as first-line treatment 1, 2
• Both approaches are acceptable Grade C recommendations for symptom relief, though duraplasty may provide improved syrinx resolution 1
• Consider cerebellar tonsil resection or reduction during the procedure to enhance syrinx improvement and symptom relief (Grade C recommendation) 1, 2
• Evaluate preoperatively whether craniocervical junction fusion is needed in addition to decompression 1

Hydrocephalus-Associated

• Treat with ventriculoperitoneal shunt first, which achieves excellent results in communicating syringes 3
• This applies to both communicating syringes (continuous with 4th ventricle) and Chiari II malformations with hydrocephalus 3

Post-Traumatic Syringomyelia

• Perform large decompressive laminectomy at the fracture site 4
• Consider syringoperitoneal or syringocisternal shunt, which produces good results 4, 3

Extramedullary Compression-Associated

• Excise the obstructing lesion at the rostral end of the syrinx, which results in cavity collapse in the majority of patients 3
• Reserve syringocisternal shunting for cases where obstruction removal fails 3

Tumor-Associated

• Perform biopsy or excision of the causal lesion with appropriate adjunctive therapy 3
• The syrinx typically resolves spontaneously after tumor resection 5

Critical Postoperative Management Principles

• Wait 6-12 months after initial surgery before considering additional neurosurgical intervention (Grade B recommendation) 1, 2, 6
• This waiting period is essential because many syringes demonstrate delayed improvement during this timeframe 1, 6
• Obtain follow-up MRI to assess radiographic syrinx improvement, but recognize that symptom resolution and syrinx resolution do not correlate directly 1, 6
• Only proceed with reoperation if there is no radiographic improvement after 6-12 months AND symptoms persist or worsen 2, 6

Second-Line Treatment Options

• For persistent focal syringes after posterior fossa decompression, syringoperitoneal shunting responds best 4
• Syringocisternal shunts (to cerebellopontine angle cistern) can collapse cavities and resolve symptoms in Chiari I cases where decompression alone fails 3
• Arachnoidolysis may be considered when reestablishing subarachnoid space continuity proves necessary 7, 5

Key Clinical Pitfalls to Avoid

• Do not rush to reoperation within the first 6-12 months, as this denies the syrinx adequate time for delayed improvement 1, 6
• Do not assume symptom-syrinx correlation: patients may improve symptomatically despite persistent radiographic syrinx, or vice versa 1, 6
• Do not treat asymptomatic or incidental syringomyelia surgically—there is no evidence supporting intervention in these cases 5
• Do not perform syrinx shunting as first-line treatment for Chiari-associated syringomyelia; address the underlying CSF flow obstruction first 7, 5
• Do not image only the symptomatic region; always obtain complete spine imaging as syringes extend beyond expected boundaries 2

Conservative Management

• Conservative (non-surgical) treatment is not recommended as the natural history involves gradual, stepwise neurological deterioration over years 7, 5
• Early surgical intervention is strongly recommended before gross neurological deficits become established 7
• Surgery is urgent when follow-up MRI shows increasing syrinx size/extension or when clinical deterioration occurs 7