Pediatric spinal nerve root enhancement: Clinical and differential considerations

Marinos Kontzialis1, Hans Michell2, Andrea Poretti2, Thierry A.G.M. Huisman2

1Division of Neuroradiology and 2Pediatric Radiology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA

eEdE-200-6875

ASNR 53rd Annual Meeting, Chicago, April 25-30, 2015mkontzi1@jhmi.edu

Disclosure

We have nothing to disclose No relevant financial relations interfering

with our presentation

Purpose

Case-based review of pediatric nerve root enhancement

Clinical and differential considerations

Introduction

Pediatric spinal nerve root enhancement:Indicates blood-nerve-barrier disruptionIs a nonspecific finding

Case 1

2-year-old with ascending weakness

A B C

Diffuse nerve root enhancement in the cervical (A), thoracic (B) and lumbar spine (C)

Guillain-Barré syndrome (GBS)

Autoantibody-mediated acute motor weakness: Pathogenesis = molecular mimicry and cross reactive

immune reaction

Prevalence: 1.2-2.3/100,000 Usually preceding upper respiratory or GI infection

(Campylobacter jejuni) Maximum weakness within 4 weeks Progressive weakness > 8 weeks chronic

inflammatory demyelinating polyneuropathy (CIDP) CSF = albumin-cytological dissociation

Guillain-Barré syndrome: MRI

1. Nerve root enhancement: > 90%

2. Different patterns of enhancement

Diffuse = 68% Ventral roots = 27% Dorsal roots = 5%

Guillain-Barré syndrome: MRI

Cranial nerve (CN) involvement = 50%

Bilateral CN V enhancement (arrows)

Differential diagnosis 1Transverse myelitis:

Quicker presentation compared to GBS (hours-few days vs. several days)

Sensory-motor level (not present in GBS)MRI: spinal cord signal abnormalities +

enhancement

10-year-old with transverse myelitis presenting with quadriplegia over 24-48 h

Differential diagnosis 2

Guillain-Barré syndrome West-Nile virus radiculitis

• Poliomyelitis-like syndrome with acute flaccid paralysis + sensory sparing

• MRI: most often normal, but ventral nerve roots enhancement is possible

• Can look identical to GBS

Case 2 8-year-old with congenital HIV infection

A B

C

Bilateral CN III enhancement (A) and diffuse nerve root enhancement and mild thickening (B, C)

Chronic inflammatory demyelinating polyneuropathy (CIDP)

Inflammation mediated demyelinationPrevalence: 1-7.7/100,000Clinically heterogeneous, grossly symmetric

sensory and/or motor neuropathyDevelops over > 8 weeks (GBS < 4 weeks)No preceding infectionCSF = increased protein, normal cell count

supportive of nerve root inflammation

Chronic inflammatory demyelinating polyneuropathy

CIDP may occur in the context of:Hepatitis CInflammatory bowel diseaseMonoclonal gammopathy of undetermined

significance (MGUS)HIV/AIDSOrgan transplantConnective tissue disorders

Chronic inflammatory demyelinating polyneuropathy

MRI: enhancement + hypertrophy of root + plexus possible widespread inflammation

Can mimic neurofibromatosis type 1

16-year-old with thickening and mild enhancement of lumbar plexus (arrowheads) and sacral nerve roots (arrows)

Case 3 9-month-old from El Salvador with a 2-

week Hx of fever, lethargy, and emesis

Diffuse meningeal enhancement in the posterior fossa (B), around the cord (B), and cauda equina nerve roots (D). Minimal clumping of the nerve roots (D).

A B C

D

Case 3

CN VI, VII, VIII enhancement +

rim enhancing lesion in the right middle

cerebellar peduncle

Basilar meningitis CN V enhancement

A B C

Tuberculosis

Most common infectious cause of spinal arachnoiditis (= inflammation of the meninges)

CSF: increased protein, decreased glucose, increased cells (mainly lymphocytes)

Nerve root enhancement = 30%, predominantly smooth

Case 4 3-year-old with subacute onset of bilateral facial

weakness and dysarthria

A B C

Diffuse nerve root enhancement in the cervical (A), thoracic (B) and lumbar spine (C)

Case 4

CN III enhancement CN VII + VIII enhancement

CN V enhancement

Bannwarth syndromeLyme meningo-radiculo-neuritis caused by spirochete

Borrelia burgdorferiMost common tick-borne disease in the USGeography, recreational habits, season (peak in the

summer) are clues!Confirmed by serum + CSF antibodiesCSF = lymphocytic meningitisErythema migrans in 89% of children = facilitates the

diagnosis

Bannwarth syndrome

MRI:MS-like periventricular white matter lesionsCranial nerve enhancementNerve root enhancement

In the appropriate geographic + seasonal setting facial diplegia/palsy = highly suggestive of Lyme disease, especially when coupled with erythema migrans

Case 5 13-year-old with progressive polyneuropathy

Thickening of the cauda equina nerve roots without evidence of enhancement (not shown)

Case 5

CN V thickening + enhancement

CN III thickening + enhancement

CN VII, VIII thickening + enhancement

Charcot-Marie-Tooth disease

Hereditary motor + sensory neuropathiesSymmetric + predominately distal motor +

sensory disturbances, slowly progressive course

MRI: typically associated with marked thickening of the nerves (hypertrophic neuropathies)

Differential diagnoses Metachromatic leukodystrophy (MLD) + Krabbe disease Can present with diffuse cranial nerve and cauda

equina enhancement May be simultaneous or precede typical white matter

abnormalities

Consider measuring arylsulfatase A + galactocerebrosidase in all children with unexplained cranial nerve and caudal nerve root enhancement

MLD Krabbe disease

Case 6 3-year-old with developmental delay + failure to thrive

Diffuse leptomeningeal + subarachnoid enhancement

Diffuse thickening of the nerve roots

Case 6

Avidly enhancing pineal mass with diffuse leptomeningeal enhancement in

the posterior fossa + around the cord

Leptomeningeal enhancement coating bilateral CN V

Pineoblastoma with leptomeningeal carcinomatosis

Neoplastic causes of nerve root enhancement in the pediatric population: MedulloblastomaGerminomaPineoblastomaPNET

EpendymomaAstrocytoma LymphomaLeukemia

Smooth nerve root enhancement

Most common, but least specific

GBS West Nile virus

radiculitis

CIDP Lyme disease Tuberculosis

Nerve root enhancement + thickening

CIDP CMT disease Leptomeningeal carcinomatosis

(enhancement can be nodular)

Summarizing tableDiagnosis Clinical CSF Clues Associations MRI

GBS <4 weeks protein Ascending paralysis, preceding infection

50% CN involvement nerve root enhancement

CIDP >8weeks protein Progressive neuropathy

Underlying disorder?

Nerve root enhancement + thickening

Meningitis Encephalopathy, meningeal signs

Protein cells Fever Empiric treatment

+ CSF± leptomeningeal and nerve root enhancement

TB Encephalopathy, meningeal signs

Protein Cells Gluc

Think about risk factors of exposure Pulmonary TB

Meningitis/arachnoiditis, tuberculomas, nerve root enhancement

Lyme RashCN VII palsy

Protein Cells

Season, recreational activities, geography Tick bite MS-like lesions, CN and

nerve root enhancement

CMT Hypertrophic neuropathies - Established diagnostic

criteriaGene testing + nerve biopsy

Nerve root and plexus thickening

MLDKrabbe - - arylsulfatase A

β-galacerebrosidase - CN + nerve root enhancement early on

Neoplastic Depends on primary

Protein Cells Nodular enhancement - Image entire neural axis

Take-home messages

1. Pediatric nerve root enhancement = nonspecific

2. Clinical presentation, imaging findings and CSF testing will point towards the right direction + guide further management

mkontzi1@jhmi.edu

Suggested literature1. Zuccoli G et al. Redefining the Guillain-Barre spectrum in children: neuroimaging findings

of cranial nerve involvement. AJNR 2011;32(4):639-42.2. Van Doorn PA et al. Clinical features, pathogenesis, and treatment of Guillain-Barre

syndrome. Lancet Neurol 2008;7:939-50.3. Mulkey SB et al. Nerve root enhancement on spinal MRI in pediatric Guillain-Barre

syndrome. Pediatr Neurol 2010;43(4):263-9.4. Vallat JM et al. Chronic inflammatory demyelinating polyradiculoneuropathy: diagnostic

and therapeutic challenges for a treatable condition. Lancet Neurol 2010;9:402-12.5. Sharma A et al. MR imaging of tubercular spinal arachnoiditis. AJR 1997;168(3):807-12.6. Hildenbrand P et al. Lyme neuroborreliosis: manifestations of a rapidly emerging

zoonosis. AJNR 2009;30:1079-87.7. Cellerini M et al. Imaging of the cauda equina in hereditary motor sensory neuropathies:

correlation with sural nerve biopsy. AJNR 2000;21:1793-8.8. Morana G et al. Enhancing cranial nerves and cauda equina: an emerging magnetic

resonance pattern in metachromatic leukodystrophy and Krabbe disease. Neuropediatrics 2009;40:291-4.

9. Zapadka M. Diffuse cauda equina nerve root enhancement. J Am Osteopath Coll Radiol 2012; Vol. 1, Issue 1.