What is the differential diagnosis and management for a patient presenting with a spinal cord lesion?

Differential Diagnosis and Management of Spinal Cord Lesions

Diagnostic Imaging Approach

MRI of the spine without and with IV contrast is the gold standard for evaluating spinal cord lesions, providing superior soft-tissue resolution and multiplanar capability to identify the etiology and guide management. 1

Imaging Protocol

• Perform MRI at minimum 1.5 Tesla field strength with sagittal dual-echo (proton-density and T2-weighted) sequences, STIR sequences, and contrast-enhanced T1-weighted spin-echo if T2 lesions are present 1
• Administer single dose gadolinium (0.1 mmol/kg) with minimum 5-minute delay before T1-weighted imaging to detect active inflammation and breakdown of blood-cord barrier 1
• Add axial T2-weighted sequences to better characterize lesion morphology and cord involvement 1
• Consider CT myelography when MRI shows findings suspicious for arachnoid cyst, arachnoid web, or ventral cord herniation 1

Differential Diagnosis by Category

Compressive/Structural Lesions

• Spondylotic myelopathy with disc-osteophyte complexes causing extrinsic cord compression—most common in cervical region, shows characteristic enhancement immediately at and below stenosis level 1
• Herniated disc material with subluxation compressing neural structures 1
• Spinal dural arteriovenous malformations/fistulas presenting with slowly progressive myelopathy, showing cord edema from venous hypertension and enlarged dorsal veins 1
• Adjacent level degenerative disease in post-surgical patients causing recurrent compression 1

Demyelinating Diseases

• Multiple sclerosis—affects 80-90% of MS patients, most commonly cervical cord, with peripherally located lesions typically <2 vertebral segments long, fulfills 2016 MAGNIMS criteria for dissemination in space 1, 2
• Neuromyelitis optica (NMO)—less common cause of chronic myelopathy with longitudinally extensive lesions 1
• Acute disseminated encephalomyelitis (ADEM)—rare cause of chronic myelopathy 1

Infectious Etiologies

• Human T-cell lymphotropic virus myelitis 1
• Tuberculosis of the spine 1
• Schistosomiasis 1
• HIV vacuolar myelopathy 1
• Tertiary syphilis 1

Metabolic Causes

• Subacute combined degeneration from vitamin B12 deficiency, copper deficiency, or nitrous oxide inhalation—shows characteristic posterior and lateral column involvement 1

Vascular Lesions

• Spinal cord stroke—can occur as sequela of initial trauma in setting of cord edema, may result in dual lesion SCI 3
• Spinal dural AVM/fistulas—demonstrate patchy intramedullary enhancement and abnormal vasculature on contrast-enhanced MRI 1

Neoplastic Causes

• Primary intramedullary tumors (astrocytoma, ependymoma)—show nodular enhancement, require distinction from syrinx and edema 1
• Metastatic tumors to spinal cord—rare cause of myelopathy 1

Autoimmune/Inflammatory

• Paraneoplastic myelopathy—requires contrast-enhanced MRI for evaluation 1
• Neuro-Behçet's disease—can present with isolated myelitis affecting lumbar cord, shows T1-hypointense/T2-hyperintense lesion with nodular enhancement 4

Radiation-Induced

• Radiation myelopathy—rare dose-dependent complication anatomically localizing to prior radiation port 1

Traumatic

• Acute spinal cord injury—requires immediate evaluation with MRI to assess cord damage and guide surgical timing 1, 5
• Dual lesion SCI—two distinct regions of injury occurring simultaneously or sequentially, presents unique rehabilitation challenges 3

Critical Management Principles

Acute Traumatic SCI Management

For suspected acute SCI, immediately apply manual spinal motion restriction, maintain systolic blood pressure >110 mmHg (MAP ≥70 mmHg), and transport directly to Level 1 trauma center within first hours to reduce mortality and improve neurological outcomes. 6, 7

Immediate Stabilization

• Apply rigid cervical collar with manual in-line stabilization (MILS) for all suspected cervical injuries 7
• Maintain mean arterial pressure ≥70 mmHg continuously during transport and first 7 days post-injury, as time with MAP <65-70 mmHg inversely correlates with neurological improvement 6, 7
• Avoid routine spinal immobilization for penetrating trauma—increases mortality without reducing neurological deficits 6

Surgical Timing

• Perform surgical decompression within 8 hours for both complete and incomplete lesions when indicated 5
• Early surgery (<8 hours) improves neurological outcomes and reduces ICU length of stay 6

Pharmacological Considerations

• Do NOT routinely administer methylprednisolone—insufficient evidence for benefit and significant complication profile including increased mortality 1
• Use succinylcholine only within 48 hours of injury; after 48 hours switch to rocuronium to avoid life-threatening hyperkalemia from denervation 6, 7

Demyelinating Disease Management

When MRI demonstrates lesions consistent with MS (peripherally located, <2 segments, cervical predominance), perform brain MRI to assess for dissemination in space and time per 2016 MAGNIMS criteria. 1

• Spinal cord MRI is mandatory when patients present with spinal cord symptoms at onset to exclude non-demyelinating pathology 1
• Spinal cord MRI is helpful when brain MRI is equivocal or shows lesions typical of MS but insufficient for DIS criteria 1

Vascular Malformation Management

For suspected spinal AVM/fistula showing cord edema and enlarged dorsal veins, perform contrast-enhanced MRI to identify abnormal vasculature and guide spinal arteriography for definitive intervention. 1

Infectious/Inflammatory Management

For neuro-Behçet's disease or other inflammatory myelopathies, administer immediate corticosteroid therapy (pulsed methylprednisolone followed by oral prednisolone) to prevent further disability and recurrence. 4

Neuropathic Pain Management

Initiate oral gabapentinoid treatment (pregabalin 150-600 mg/day) for >6 months to control neuropathic pain associated with spinal cord lesions, adding tricyclic antidepressants or serotonin reuptake inhibitors when monotherapy insufficient. 1, 8

• Pregabalin demonstrates statistically significant improvement in pain scores with 30-50% reduction from baseline in SCI-related neuropathic pain 8
• Introduce multimodal analgesia combining non-opioid analgesics, ketamine, and opioids during surgical management to prevent prolonged pain 1

Critical Pitfalls to Avoid

• Do not delay MRI with contrast when evaluating chronic or progressive myelopathy—metabolic causes, infections, and demyelinating diseases require contrast for accurate diagnosis 1
• Do not assume single-level pathology—dual lesion SCI can occur with sequential injuries requiring comprehensive spine imaging 3
• Do not overlook lumbar cord involvement in systemic inflammatory diseases like neuro-Behçet's—can present as isolated myelitis 4
• Do not confuse demyelinating plaques with neoplasm on imaging—MS can mimic intramedullary tumor even on MRI, requiring biopsy for definitive diagnosis in atypical presentations 2
• Do not use rigid immobilization devices if untrained—may interfere with airway patency and cause harm 6