What is the treatment for a patient with a thoracic syrinx?

Treatment of Thoracic Syrinx

Surgical decompression targeting the underlying cause is the definitive treatment for symptomatic thoracic syringomyelia, with posterior fossa decompression for Chiari-associated cases and spinal decompression or shunting procedures for other etiologies. 1

Initial Diagnostic Workup

• Obtain MRI of the entire spine (not just the symptomatic region) using T1-weighted, T2-weighted, FLAIR, and post-contrast sequences to determine the full extent of the syrinx and identify the underlying cause 1
• Include brain imaging to evaluate for Chiari malformation, which is present in 25-50% of syringomyelia cases and represents the most common etiology 1
• Look specifically for spinal arachnoiditis, arachnoid webs, epidural lipomatosis, or other compressive lesions that may be causing CSF flow obstruction 2, 3, 4

Surgical Management Based on Etiology

Chiari Malformation-Associated Syringomyelia

Posterior fossa decompression with or without duraplasty is the first-line surgical treatment for Chiari-associated thoracic syrinx 1

• Both techniques (with and without duraplasty) demonstrate benefit for symptom relief and syrinx reduction 1
• Consider cerebellar tonsil reduction during the decompression procedure to enhance syrinx improvement (Grade C recommendation) 1
• This approach addresses the underlying CSF flow obstruction at the foramen magnum 5

Spinal Arachnoiditis or Arachnoid Web-Associated Syrinx

• Perform laminectomy at the level of the web or adhesions with surgical excision of the arachnoid web to decompress the subarachnoid space and restore normal CSF flow 2
• The syrinx typically originates at the thoracic level where severe subarachnoid adhesion is present 3
• Surgical resection can be curative with possible complete remission of symptoms and normalization of spinal anatomy 2

Shunting Procedures

When primary decompression is not feasible or has failed:

• Syringoperitoneal shunt is the most commonly used shunting procedure 3
• Syringosubarachnoid shunt can be performed, particularly for short thoracic syringes using minimally invasive keyhole laminectomy 3, 6
• Shunting procedures are effective in approximately 60% of patients with neurologic improvement and decreased syrinx size 3
• Be aware that repeat shunting operations may be required in up to 53% of patients (8 of 15 in one series) within 2 months to 12 years after initial surgery 3

Post-Operative Management and Monitoring

Allow 6-12 months for syrinx reduction after initial surgery before considering additional intervention (Grade B recommendation) 1, 7

• Obtain follow-up MRI at 6-12 months post-operatively to assess syrinx size and CSF flow 1, 7
• Understand that symptom resolution and syrinx resolution do not correlate directly—clinical improvement can occur without complete radiographic resolution, and vice versa 7
• Monitor for new or worsening symptoms during this observation period 7

Indications for Reoperation

Consider additional neurosurgical intervention if:

• No radiographic improvement of the syrinx after 6-12 months of observation 1, 7
• Progressive clinical deterioration despite initial surgery 1
• Development of new neurologic symptoms suggesting syrinx expansion 2

Critical Pitfalls to Avoid

• Do not image only the symptomatic spinal region—thoracic syringes can extend rostrally to C1 or caudally beyond the initially suspected area 1, 2
• Do not rush to reoperation before allowing 6-12 months for syrinx improvement, as many resolve during this timeframe 1, 7
• Do not assume stability based on lack of symptoms alone—syringes can enlarge asymptomatically, and prolonged severe stenosis can cause irreversible spinal cord damage 8
• Do not delay evaluation of new or worsening symptoms, as these may indicate recurrence or complications requiring intervention 8

Expected Outcomes

• Neurologic improvement occurs in approximately 60% of patients with appropriate surgical intervention 3
• Complete resolution of symptoms is possible, particularly with arachnoid web excision 2
• Syringomyelia is a progressive disease that can expand rostrally with worsening symptoms if left untreated 2
• Some patients may experience gradual deterioration (approximately 33% in one series) despite surgical treatment 3