What is the appropriate work‑up and management for a patient with a cervical syrinx on MRI presenting with neck pain and worsening headaches?

Workup and Management of Cervical Syrinx with Neck Pain and Worsening Headaches

Immediately obtain MRI of the entire spine (cervical through thoracic) with and without contrast to evaluate syrinx extent, identify underlying etiology (Chiari malformation, spinal cord tethering, arachnoid adhesions, tumor, or cervical stenosis), and exclude serious pathology requiring urgent neurosurgical intervention. 1, 2

Critical Red Flag Assessment

Before proceeding with further workup, systematically screen for features that mandate urgent neurosurgical evaluation:

• Progressive neurological deficits including weakness, sensory loss in a cape-like distribution (dissociated sensory loss), bowel/bladder dysfunction, or myelopathic signs (hyperreflexia, clonus, Babinski sign) indicate active spinal cord compression requiring urgent surgical consultation 1, 2
• Constitutional symptoms such as fever, unexplained weight loss, or night sweats suggest infection or malignancy 1, 2
• History of malignancy, immunosuppression, or IV drug use raises concern for metastatic disease or vertebral osteomyelitis 2
• Intractable pain despite conservative therapy is a red flag for serious underlying pathology 2
• Elevated inflammatory markers (ESR, CRP, WBC) warrant investigation for infection or inflammatory disease 2

Comprehensive MRI Protocol

The imaging must extend beyond the cervical spine alone:

• Order MRI cervical AND thoracic spine because syringes commonly extend into the thoracic region, and the full extent determines surgical planning 3, 4, 5
• Include contrast administration to evaluate for tumors (intramedullary or extramedullary), inflammatory processes, or vascular malformations that may cause or coexist with syrinx 1
• Phase-contrast cine MRI sequences should be added to assess CSF flow dynamics at the foramen magnum and identify flow obstruction, which is critical for understanding syrinx pathophysiology 6

Identifying the Underlying Etiology

Syringes do not occur in isolation—the MRI must identify the causative pathology:

• Chiari I malformation is the most common association, characterized by cerebellar tonsillar herniation >5mm below the foramen magnum with partial CSF flow obstruction 6
• Cervical spinal stenosis from spondylosis can cause sustained cord compression leading to arachnoid fibrosis and syrinx formation 4, 5
• Spinal cord tethering or arachnoid adhesions create focal CSF flow blocks that propagate syrinx fluid 3
• Intramedullary or extramedullary tumors must be excluded with contrast-enhanced sequences 1
• Post-traumatic syrinx should be considered if there is any remote history of spinal trauma 3

Neurosurgical Referral Criteria

Refer immediately to neurosurgery if any of the following are present:

• Progressive neurological deficits of any kind, as these indicate active myelopathy requiring surgical decompression 3, 6
• Syrinx associated with Chiari I malformation typically requires foramen magnum decompression (suboccipital craniectomy, C1 laminectomy, duraplasty) to restore CSF flow and halt syrinx progression 6
• Syrinx with cervical stenosis may require posterior decompressive laminectomy to relieve cord compression and allow syrinx resolution 4, 5
• Syrinx with cord tethering or adhesions requires laminectomy, lysis of adhesions, untethering, syrinx fenestration, and duraplasty 3

Conservative Management for Stable Syrinx

If the syrinx is incidentally discovered, neurologically stable, and associated only with neck pain and headaches without red flags:

• Serial MRI surveillance every 6-12 months to monitor syrinx size and detect progression, as 11 out of 13 cases in one series remained stable without intervention 5
• Multimodal conservative therapy including gentle cervical spine mobilization, soft tissue manipulation, and rehabilitative exercises may improve symptoms in stable patients, though evidence is limited to case reports 7
• Avoid high-velocity cervical manipulation given the risk of neurological injury in the presence of syrinx 7
• Physical therapy focused on core strengthening and postural correction to reduce mechanical stress on the cervical spine 7

Understanding Syrinx Pathophysiology

The mechanism of syrinx progression informs treatment decisions:

• Syringes propagate through a "piston mechanism" where partial CSF flow obstruction (from Chiari tonsils, stenosis, or adhesions) creates enlarged cervical subarachnoid pressure waves that compress the cord externally and drive syrinx fluid caudally with each heartbeat 6
• Surgical decompression eliminates this mechanism by restoring normal CSF flow, which allows the syrinx to collapse without direct syrinx drainage 6
• Syrinx fluid flows inferiorly during systole and superiorly during diastole on cine MRI, and this abnormal flow pattern resolves after successful decompression 6

Common Pitfalls to Avoid

• Do not attribute all symptoms to degenerative changes alone—cervical spondylosis is present in 85% of asymptomatic individuals over 30 years, and the syrinx may be the true cause of progressive symptoms 2, 5
• Do not delay imaging in the presence of worsening headaches—this may indicate progressive syrinx expansion or increased intracranial pressure 1, 2
• Do not assume the syrinx is idiopathic without comprehensive imaging—an underlying cause (Chiari, stenosis, tumor, tethering) is identifiable in most cases and determines treatment 3, 6, 4
• Do not perform isolated cervical imaging—the syrinx often extends into the thoracic spine, and missing this leads to incomplete surgical planning 3, 4, 5

Long-Term Monitoring

Even after successful treatment, ongoing surveillance is essential:

• Repeat MRI at 6 months post-surgery to document syrinx reduction and assess adequacy of decompression 6
• Annual clinical examinations and MRI for at least 3-5 years to detect late recurrence or progression 3, 6
• Monitor for new neurological symptoms that may indicate syrinx re-expansion or inadequate initial decompression 3, 6