---
title: "CIDP"
docid: "12e4033c-edc8-46ff-8081-3acc433cda78"
authors:
- key: "b2e6dabb-ee1c-42a4-a332-9f0814c1c607"
value: "Surjith Vattoth, MD, FRCR"
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name: "CIDP"
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lastUpdated: "06/08/20"
pageDescription: "CIDP"
pageKeywords: "Brain, Diagnosis, Pathology-Based Diagnoses, Infectious, Inflammatory, and Demyelinating Disease, Inflammatory and Demyelinating Disease, CIDP"
pageTitle: "CIDP | STATdx"
enhancedTitle: "CIDP"
type: "DX"
references: true
breadcrumbs:
- "Brain"
- "Diagnosis"
- "Pathology-Based Diagnoses"
- "Infectious, Inflammatory, and Demyelinating Disease"
- "Inflammatory and Demyelinating Disease"
- "CIDP"
---
# KEY FACTS
- ## Terminology
- Clinically heterogeneous, grossly symmetric, sensory & motor neuropathy evolving as monophasic, relapsing, or progressive disorder
- Develops over > 8 weeks
- ## Imaging
- Sagittal FLAIR may reveal hyperintense brain lesions similar to multiple sclerosis
- Enlargement & abnormal T2 hyperintensity of nerve roots, plexi, or peripheral nerves
- ↑ nerve root diameter, cross-sectional area (CSA), & volume
- Spinal nerve roots & peripheral nerves (extraforaminal > intradural)
- Lumbar > cervical, brachial plexus, thoracic/intercostal > cranial nerve
- Fair degree of CSA correlation between high-resonance nerve ultrasound (HRUS) & MR neurography (MRN)
- ## Top Differential Diagnoses
- Guillain-Barré (AIDP)
- Inherited demyelinating neuropathy (Charcot-Marie-Tooth)
- Neurofibromatosis type 1, schwannomatosis
- ## Pathology
- Autoimmune disease of cellular & humoral immunity
- Hallmarks of CIDP: Enlarged nerves with onion bulb formations, demyelination
- ## Clinical Issues
- Usually **clinical**diagnosis based on progressive weakness/sensory loss & response to steroids
- Typical: Symmetric proximal & distal weakness, sensory loss
- Abnormal EMG/NCV: Key electrophysiologic features → nerve conduction block, slowed conduction velocities suggestive of demyelination
- Diagnosis relies primarily on clinical, electrophysiologic examination supplemented by nerve biopsy
# TERMINOLOGY
- ## Abbreviations
- Chronic inflammatory demyelinating polyneuropathy (CIDP)
- ## Synonyms
- Chronic inflammatory demyelinating polyradiculoneuropathy
- ## Definitions
- Chronic acquired, immune-mediated demyelinating neuropathy characterized by relapsing or progressive muscle weakness ± sensory loss
# IMAGING
- ## General Features
- ### Best diagnostic clue
- Enlargement & abnormal T2 hyperintensity of nerve roots, plexi, or peripheral nerves
- Spinal nerve roots & peripheral nerves (extraforaminal > intradural)
- Lumbar > cervical, brachial plexus, thoracic/intercostal > cranial nerves (CNs)
- ### Size
- Nerve size varies; small → very large
- Mean diameter of spinal nerve roots in CIDP: Cervical 6-6.8 mm; lumbosacral 7.3-10.4 mm
- 5-mm best cut-off value of C6, C7, C8 nerve root diameters to distinguish CIDP patients from controls
- CIDP nerves larger volumes, which positively correlate with disease duration
- Recent MR neurography (MRN) of L3-S1 nerve roots of lumbosacral plexus using 3D multiple echo recalled gradient-echo (3D MERGE) sequence showed
- ↑ mean cross-sectional area (CSA): 28.04 ± 8.55 mm² in CIDP (14.91 ± 2.36 square mm² in normal); optimal cut-off value 19.20 mm²
- ### Morphology
- Focal or diffuse fusiform enlargement of cauda equina, nerve roots/plexi, & peripheral nerves
- ## CT Findings
- ### NECT
- Isodense nerve enlargement
- ### CECT
- Mild to moderate nerve enhancement
- ## MR Findings
- ### T2WI
- Enlargement, abnormal hyperintensity of intradural & extradural spinal nerves/branches
- ### FLAIR
- Sagittal FLAIR may reveal hyperintense brain lesions similar to multiple sclerosis (MS)
- ### DWI
- Diffusion-weighted MRN
- DTI: ↓ nerve fractional anisotropy (FA) (mean 0.42 ± 0.08) in CIDP compared to healthy controls (0.52 ± 0.04)
- ↓ FA due to ↑ radial diffusivity (RD); axial diffusivity (AD) not significant
- FA & RD correlate strongly with electrophysiological markers of demyelination
- ### T1WI C+
- Mild to moderate nerve enhancement
- ## Ultrasonographic Findings
- ### Grayscale ultrasound
- Hypoechoic, hypertrophic nerves
- Fair degree of CSA correlation in high resonance nerve US (HRUS) & MRN of cervical plexus, & peripheral nerves in CIDP
- CSA in HRUS correlate well with markers of nerve integrity, such as ↓ FA in DTI & with ↑ T2 signal
- HRUS-CSA of interscalene brachial plexus correlated significantly with MRN-CSA & T2 signal of L5 & S1 lumbar plexus roots
- ## Imaging Recommendations
- ### Best imaging tool
- MRN, T2WI, enhanced coronal & axial T1WI sequences with fat suppression best delineate nerve lesions
- Brain MR to detect subclinical CNS demyelination
# DIFFERENTIAL DIAGNOSIS
- ## Conditions Recently Proposed to be Included Under CIDP Syndrome
- Antimyelin associated glycoprotein (MAG) neuropathy
- Chronic neuropathies associated with IgG4 antibodies against paranodal/nodal proteins; chronic immune sensory polyradiculopathy (CISP); multifocal motor neuropathy
- [Guillain-Barré (Acute Inflammatory Demyelinating Polyneuropathy)](/document/guillain-barr-spectrum-disorders/c1f52a65-920e-4e28-8a75-07dfa208f290)
- Pial, nerve root enhancement similar to CIDP
- Differs from CIDP in onset duration, clinical course
- Acute onset of ascending paralysis with relative sensory preservation
- [Hereditary Motor and Sensory Neuropathy](/document/hypertrophic-neuropathy/e246f4d1-0262-4ca7-b8e1-6f2a4bd67c06)
- Also called Charcot-Marie-Tooth (CMT) disease
- CMT1, CMT 3 (Dejerine-Sottas disease) CMT4, CMTX1
- Genetic testing, clinical phenotype distinguish from CIDP
- [Neurofibromatosis Type 1](/document/neurofibromatosis-type-1-spine/89236653-e750-4fa7-b2b1-0a3c4ed31a87)
- Diffuse nerve root enlargement, enhancement
- Genetic testing & distinctive clinical stigmata to distinguish
- ## Lateral Meningocele
- CSF density/signal intensity (not solid) ± foraminal enlargement, dural ectasia
- Usually coexisting NF1 or connective tissue disorder (Marfan syndrome)
- ## Schwannomatosis
- Multiple schwannomas of peripheral nerves & CNs [nonvestibular schwannomas (nVS)]
- However, unilateral VS described with germline mutations of Schwannomatosis in SMARCB1 & LZTR1
- ## Other Clinical Differential Diagnosis
- Diabetic neuropathy, amyloid neuropathy due to TTR mutations, vasculitic neuropathy, POEMS syndrome
# PATHOLOGY
- ## General Features
- ### Etiology
- Exact pathogenesis of CIDP unclear; involves both cellular & humoral immune factors
- Polyneuropathies co-occurring with MS: Underdiagnosed; extra disability burden; includes CIDP
- 1/3 of MS-CIDP cases with serum testing show IgG4 autoantibodies to neurofascin-155
- ## Gross Pathologic & Surgical Features
- Extensive fusiform nerve enlargement ± gross onion bulb formations
- ## Microscopic Features
- Large nerve, onion bulb formations, demyelination
- Macrophage, T-cell infiltration → perivascular inflammatory infiltrates, nerve demyelination & remyelination
- Onion bulb formation: Excessive Schwann cell process proliferation → repetitive demyelination/remyelination
# CLINICAL ISSUES
- ## Presentation
- ### Most common signs/symptoms
- Mixed sensorimotor neuropathy; typical form: Symmetric proximal & distal weakness, sensory loss
- Rarer atypical form (Lewis-Sumner syndrome)
- Predominantly uni- or multifocal as well as distal
- CNs are occasionally affected, with particular tropism for CNVII, but ophthalmoplegia or bulbar weakness can be present
- ### Other signs/symptoms
- Chronic progressive: Progressively deteriorate until treatment is given
- ## Demographics
- ### Sex
- M = F
- ## Natural History & Prognosis
- Average disease duration: 7.5 years
- ## Treatment
- European Federation of Neurological Societies/Peripheral Nerve Society Guideline on management of chronic inflammatory demyelinating polyradiculoneuropathy; immunomodulation or immunosuppression therapy
# DIAGNOSTIC CHECKLIST
- ## Consider
- Consider CIDP in differential of nerve root/peripheral nerve enlargement
- ## Image Interpretation Pearls
- MR findings imperfectly correlate with clinical disease activity/severity, laboratory findings
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## References
# Selected References
1. [Campagnolo M et al: Sporadic hereditary neuropathies misdiagnosed as chronic inflammatory demyelinating polyradiculoneuropathy: Pitfalls and red flags. J Peripher Nerv Syst. 25(1):19-26, 2020](http://www.ncbi.nlm.nih.gov/pubmed/?term=31919945%5Bpmid%5D)
1. [Van den Bergh PYK et al: Boundaries of chronic inflammatory demyelinating polyradiculoneuropathy. J Peripher Nerv Syst. 25(1):4-8, 2020](http://www.ncbi.nlm.nih.gov/pubmed/?term=31981273%5Bpmid%5D)
1. [Wu F et al: MR neurography of lumbosacral nerve roots: diagnostic value in chronic inflammatory demyelinating polyradiculoneuropathy and correlation with electrophysiological parameters. Eur J Radiol. 124:108816, 2020](http://www.ncbi.nlm.nih.gov/pubmed/?term=31923808%5Bpmid%5D)
1. [Suanprasert N et al: Polyneuropathies and chronic inflammatory demyelinating polyradiculoneuropathy in multiple sclerosis. Mult Scler Relat Disord. 30:284-90, 2019](http://www.ncbi.nlm.nih.gov/pubmed/?term=30870805%5Bpmid%5D)
1. [Pitarokoili K et al: High-resolution nerve ultrasound and magnetic resonance neurography as complementary neuroimaging tools for chronic inflammatory demyelinating polyneuropathy. Ther Adv Neurol Disord. 11:1756286418759974, 2018](http://www.ncbi.nlm.nih.gov/pubmed/?term=29552093%5Bpmid%5D)
1. [Ishikawa T et al: MR neurography for the evaluation of CIDP. Muscle Nerve. 55(4):483-9, 2017](http://www.ncbi.nlm.nih.gov/pubmed/?term=27500391%5Bpmid%5D)
1. [Kronlage M et al: Large coverage MR neurography in CIDP: diagnostic accuracy and electrophysiological correlation. J Neurol. 264(7):1434-43, 2017](http://www.ncbi.nlm.nih.gov/pubmed/?term=28620719%5Bpmid%5D)
1. [Kronlage M et al: Diffusion tensor imaging in chronic inflammatory demyelinating polyneuropathy: diagnostic accuracy and correlation with electrophysiology. Invest Radiol. 52(11):701-7, 2017](http://www.ncbi.nlm.nih.gov/pubmed/?term=28574858%5Bpmid%5D)
1. [Said G et al: Chronic inflammatory demyelinative polyneuropathy. Handb Clin Neurol. 115:403-13, 2013](http://www.ncbi.nlm.nih.gov/pubmed/?term=23931792%5Bpmid%5D)
1. [Mahdi-Rogers M et al: Overview of the pathogenesis and treatment of chronic inflammatory demyelinating polyneuropathy with intravenous immunoglobulins. Biologics. 4:45-9, 2010](http://www.ncbi.nlm.nih.gov/pubmed/?term=20376173%5Bpmid%5D)
1. [Tracy JA et al: Investigations and treatment of chronic inflammatory demyelinating polyradiculoneuropathy and other inflammatory demyelinating polyneuropathies. Curr Opin Neurol. 23(3):242-8, 2010](http://www.ncbi.nlm.nih.gov/pubmed/?term=20389243%5Bpmid%5D)
1. [Vallat JM et al: Chronic inflammatory demyelinating polyradiculoneuropathy: diagnostic and therapeutic challenges for a treatable condition. Lancet Neurol. 9(4):402-12, 2010](http://www.ncbi.nlm.nih.gov/pubmed/?term=20298964%5Bpmid%5D)
1. [Van den Bergh PY et al: European Federation of Neurological Societies/Peripheral Nerve Society guideline on management of chronic inflammatory demyelinating polyradiculoneuropathy: report of a joint task force of the European Federation of Neurological Societies and the Peripheral Nerve Society - first revision. Eur J Neurol. 17(3):356-63, 2010](http://www.ncbi.nlm.nih.gov/pubmed/?term=20456730%5Bpmid%5D)
1. [Brannagan TH 3rd: Current treatments of chronic immune-mediated demyelinating polyneuropathies. Muscle Nerve. 39(5):563-78, 2009](http://www.ncbi.nlm.nih.gov/pubmed/?term=19301378%5Bpmid%5D)
1. [Laughlin RS et al: Incidence and prevalence of CIDP and the association of diabetes mellitus. Neurology. 73(1):39-45, 2009](http://www.ncbi.nlm.nih.gov/pubmed/?term=19564582%5Bpmid%5D)
1. [Tazawa K et al: Spinal nerve root hypertrophy on MRI: clinical significance in the diagnosis of chronic inflammatory demyelinating polyradiculoneuropathy. Intern Med. 47(23):2019-24, 2008](http://www.ncbi.nlm.nih.gov/pubmed/?term=19043253%5Bpmid%5D)
1. [Tsuchiya K et al: Demonstration of spinal cord and nerve root abnormalities by diffusion neurography. J Comput Assist Tomogr. 32(2):286-90, 2008](http://www.ncbi.nlm.nih.gov/pubmed/?term=18379319%5Bpmid%5D)
1. [Said G: Chronic inflammatory demyelinating polyneuropathy. Neuromuscul Disord. 16(5):293-303, 2006](http://www.ncbi.nlm.nih.gov/pubmed/?term=16631367%5Bpmid%5D)
1. [Köller H et al: Chronic inflammatory demyelinating polyneuropathy--update on pathogenesis, diagnostic criteria and therapy. Curr Opin Neurol. 18(3):273-8, 2005](http://www.ncbi.nlm.nih.gov/pubmed/?term=15891411%5Bpmid%5D)
1. [Matsuoka N et al: Detection of cervical nerve root hypertrophy by ultrasonography in chronic inflammatory demyelinating polyradiculoneuropathy. J Neurol Sci. 219(1-2):15-21, 2004](http://www.ncbi.nlm.nih.gov/pubmed/?term=15050432%5Bpmid%5D)
1. [Cocito D et al: Different clinical, electrophysiological and immunological features of CIDP associated with paraproteinaemia. Acta Neurol Scand. 108(4):274-80, 2003](http://www.ncbi.nlm.nih.gov/pubmed/?term=12956862%5Bpmid%5D)
1. [Fee DB et al: Resolution of chronic inflammatory demyelinating polyneuropathy-associated central nervous system lesions after treatment with intravenous immunoglobulin. J Peripher Nerv Syst. 8(3):155-8, 2003](http://www.ncbi.nlm.nih.gov/pubmed/?term=12904236%5Bpmid%5D)
1. [Haq RU et al: Chronic inflammatory demyelinating polyradiculoneuropathy in diabetic patients. Muscle Nerve. 27(4):465-70, 2003](http://www.ncbi.nlm.nih.gov/pubmed/?term=12661048%5Bpmid%5D)
1. [Magda P et al: Comparison of electrodiagnostic abnormalities and criteria in a cohort of patients with chronic inflammatory demyelinating polyneuropathy. Arch Neurol. 60(12):1755-9, 2003](http://www.ncbi.nlm.nih.gov/pubmed/?term=14676052%5Bpmid%5D)
1. [Odaka M et al: Patients with chronic inflammatory demyelinating polyneuropathy initially diagnosed as Guillain-Barre syndrome. J Neurol. 250(8):913-6, 2003](http://www.ncbi.nlm.nih.gov/pubmed/?term=12928908%5Bpmid%5D)
1. [Oguz B et al: Diffuse spinal and intercostal nerve involvement in chronic inflammatory demyelinating polyradiculoneuropathy: MRI findings. Eur Radiol. 13 Suppl 4:L230-4, 2003](http://www.ncbi.nlm.nih.gov/pubmed/?term=15018192%5Bpmid%5D)
1. [Press R et al: Aberrated levels of cerebrospinal fluid chemokines in Guillain-Barre syndrome and chronic inflammatory demyelinating polyradiculoneuropathy. J Clin Immunol. 23(4):259-67, 2003](http://www.ncbi.nlm.nih.gov/pubmed/?term=12959218%5Bpmid%5D)
1. [Rodriguez-Casero MV et al: Childhood chronic inflammatory demyelinating polyneuropathy with central nervous system demyelination resembling multiple sclerosis. Neuromuscul Disord. 13(2):158-61, 2003](http://www.ncbi.nlm.nih.gov/pubmed/?term=12565914%5Bpmid%5D)
1. [Ropper AH: Current treatments for CIDP. Neurology. 60(8 Suppl 3):S16-22, 2003](http://www.ncbi.nlm.nih.gov/pubmed/?term=12707418%5Bpmid%5D)
1. [Saperstein DS et al: Current concepts and controversy in chronic inflammatory demyelinating polyneuropathy. Curr Neurol Neurosci Rep. 3(1):57-63, 2003](http://www.ncbi.nlm.nih.gov/pubmed/?term=12507413%5Bpmid%5D)
1. [Toyka KV et al: The pathogenesis of CIDP: rationale for treatment with immunomodulatory agents. Neurology. 60(8 Suppl 3):S2-7, 2003](http://www.ncbi.nlm.nih.gov/pubmed/?term=12707416%5Bpmid%5D)
1. [Costello F et al: Childhood-onset chronic inflammatory demyelinating polyradiculoneuropathy with cranial nerve involvement. J Child Neurol. 17(11):819-23, 2002](http://www.ncbi.nlm.nih.gov/pubmed/?term=12585721%5Bpmid%5D)
1. Cros D: Peripheral Neuropathy. 1st ed. Philadelphia: Lippincott Williams & Wilkins: 432, 2001
1. [Sabatelli M et al: Pure motor chronic inflammatory demyelinating polyneuropathy. J Neurol. 248(9):772-7, 2001](http://www.ncbi.nlm.nih.gov/pubmed/?term=11596782%5Bpmid%5D)
1. [Saperstein DS et al: Clinical spectrum of chronic acquired demyelinating polyneuropathies. Muscle Nerve. 24(3):311-24, 2001](http://www.ncbi.nlm.nih.gov/pubmed/?term=11353415%5Bpmid%5D)
1. [Taniguchi N et al: Sonographic detection of diffuse peripheral nerve hypertrophy in chronic inflammatory demyelinating polyradiculoneuropathy. J Clin Ultrasound. 28(9):488-91, 2000](http://www.ncbi.nlm.nih.gov/pubmed/?term=11056027%5Bpmid%5D)
1. [Van den Bergh PY et al: Chronic demyelinating hypertrophic brachial plexus neuropathy. Muscle Nerve. 23(2):283-8, 2000](http://www.ncbi.nlm.nih.gov/pubmed/?term=10639625%5Bpmid%5D)
1. [Duarte J et al: Hypertrophy of multiple cranial nerves and spinal roots in chronic inflammatory demyelinating neuropathy. J Neurol Neurosurg Psychiatry. 67(5):685-7, 1999](http://www.ncbi.nlm.nih.gov/pubmed/?term=10519883%5Bpmid%5D)
1. [Midroni G et al: MRI of the cauda equina in CIDP: clinical correlations. J Neurol Sci. 170(1):36-44, 1999](http://www.ncbi.nlm.nih.gov/pubmed/?term=10540034%5Bpmid%5D)
1. [Mizuno K et al: Chronic inflammatory demyelinating polyradiculoneuropathy with diffuse and massive peripheral nerve hypertrophy: distinctive clinical and magnetic resonance imaging features. Muscle Nerve. 21(6):805-8, 1998](http://www.ncbi.nlm.nih.gov/pubmed/?term=9585338%5Bpmid%5D)
1. [Kuwabara S et al: Magnetic resonance imaging at the demyelinative foci in chronic inflammatory demyelinating polyneuropathy. Neurology. 48(4):874-7, 1997](http://www.ncbi.nlm.nih.gov/pubmed/?term=9109870%5Bpmid%5D)
1. [Simmons Z et al: Chronic inflammatory demyelinating polyradiculoneuropathy in children: I. Presentation, electrodiagnostic studies, and initial clinical course, with comparison to adults. 20(12):1569-75, 1997](http://www.ncbi.nlm.nih.gov/pubmed/?term=9390670%5Bpmid%5D)
1. [Van Es HW et al: Magnetic resonance imaging of the brachial plexus in patients with multifocal motor neuropathy. Neurology. 48(5):1218-24, 1997](http://www.ncbi.nlm.nih.gov/pubmed/?term=9153446%5Bpmid%5D)
## Images
### Selected Images
. 5 mm is considered an adequate cut-off value of cervical spinal nerve root diameter, discriminating CIDP from controls. Mean diameter of spinal nerve roots in CIDP: Cervical 6-6.8 mm; lumbosacral 7.3-10.4 mm.](images/app.statdx.com_image_thumbnail_e0d1598d-4a92-4d78-9124-87f27a196230_annotated_true_size_900_quality_90_8ebe0b28_20251018T122453Z.jpg)
*Sagittal T1 C+ MR of the cervical spine shows marked hypertrophy and enhancement of all exiting cervical nerve roots . 5 mm is considered an adequate cut-off value of cervical spinal nerve root diameter, discriminating CIDP from controls. Mean diameter of spinal nerve roots in CIDP: Cervical 6-6.8 mm; lumbosacral 7.3-10.4 mm.*
*Sagittal T1 C+ MR of the cervical spine shows marked hypertrophy and enhancement of all exiting cervical nerve roots . 5 mm is considered an adequate cut-off value of cervical spinal nerve root diameter, discriminating CIDP from controls. Mean diameter of spinal nerve roots in CIDP: Cervical 6-6.8 mm; lumbosacral 7.3-10.4 mm.*
*Sagittal T1 C+ MR of the cervical spine shows marked hypertrophy and enhancement of all exiting cervical nerve roots . 5 mm is considered an adequate cut-off value of cervical spinal nerve root diameter, discriminating CIDP from controls. Mean diameter of spinal nerve roots in CIDP: Cervical 6-6.8 mm; lumbosacral 7.3-10.4 mm.*
*Sagittal T2WI MR reveals enlargement and T2 hyperintensity of exiting extradural lumbosacral nerves . High signal of CSF should be excluded while measuring nerve root size/area in T2 MR.*
*Sagittal T2WI MR reveals enlargement and T2 hyperintensity of exiting extradural lumbosacral nerves . High signal of CSF should be excluded while measuring nerve root size/area in T2 MR.*
*Axial T1WI C+ MR depicts enlargement and abnormal enhancement of exiting extradural lumbosacral nerves . Blood-nerve barrier breakdown can cause contrast enhancement. Axon loss associated with demyelination is the most important factor of disability and resistance to treatment. Root hypertrophy also may cause stenosis symptoms.*
*Axial T1WI C+ MR depicts enlargement and abnormal enhancement of exiting extradural lumbosacral nerves . Blood-nerve barrier breakdown can cause contrast enhancement. Axon loss associated with demyelination is the most important factor of disability and resistance to treatment. Root hypertrophy also may cause stenosis symptoms.*
in a typical case of marked fusiform CIDP nerve enlargement with brain demyelination.](images/app.statdx.com_image_thumbnail_8ef8ec72-8984-4f90-8380-953114da6604_annotated_true_size_900_quality_90_c59fe9eb_20251018T122453Z.jpg)
*Sagittal FLAIR MR demonstrates periventricular ovoid hyperintensities in a typical case of marked fusiform CIDP nerve enlargement with brain demyelination.*
*Sagittal FLAIR MR demonstrates periventricular ovoid hyperintensities in a typical case of marked fusiform CIDP nerve enlargement with brain demyelination.*
### Additional Images
.](images/app.statdx.com_image_thumbnail_385d96c2-5ef1-466a-bbf7-bcfbf8fb9433_annotated_true_size_900_quality_90_b76815ce_20251018T122453Z.jpg)
*Axial T1WI C+ MR shows thickening and enhancement of ventral and dorsal cauda equina nerve roots .*
*Axial T1WI C+ MR shows thickening and enhancement of ventral and dorsal cauda equina nerve roots .*
*Sagittal T2WI MR demonstrates diffuse thickening of the intradural cauda equina nerve roots.*
*Sagittal T2WI MR demonstrates diffuse thickening of the intradural cauda equina nerve roots.*
*Sagittal FLAIR MR of the brain in a CIDP patient shows a typical paraventricular demyelinating lesion similar to those seen in multiple sclerosis patients.*
*Sagittal FLAIR MR of the brain in a CIDP patient shows a typical paraventricular demyelinating lesion similar to those seen in multiple sclerosis patients.*
*Sagittal T2WI MR depicts enlarged lumbar nerve roots extending into extraforaminal ventral primary rami .*
*Sagittal T2WI MR depicts enlarged lumbar nerve roots extending into extraforaminal ventral primary rami .*
*Axial T2WI MR shows diffuse thickening and hyperintensity of thoracic nerve roots and paraspinal intercostal nerves.*
*Axial T2WI MR reveals bilateral symmetric enlargement, hyperintensity of cervical nerve roots and brachial plexus .*
*Sagittal T1WI C+ MR demonstrates diffuse pial thickening and enhancement extending into the cauda equina nerve roots. Clinical course distinguished from Guillain-Barré (AIDP).*
and lumbosacral trunk .](images/app.statdx.com_image_thumbnail_7776240a-5af6-404a-bc66-83b9ee89150e_size_168_quality_85_e3313250_20251018T095234Z.jpg)
*Axial T2WI MR shows marked enlargement of the lumbar/sacral nerve roots and lumbosacral trunk .*