CASE 20

By Dr. Sattam Lingawi and Dr. Alaa Al-Turkustani

HISTORY: Withheld.

What are your findings?

What is the differential diagnosis?

FINDINGS:

Fig. 1: Sagittal T2 WI of the lumbar spine demonstrating thickening of the Cauda Equina nerve roots.

Fig. 2: Sagittal non-enhanced T1 WI, Fig. 3: Sagittal contrast enhanced T1 WI with fat saturation, Fig 4 & 5 Axial T1+C of the lumbar spine demonstrate significant thickening and enhancement of the Cauda Equine nerve roots without evidence of nodularity, the enhancement is more prominent on the anterior aspect of the cord.

DIFFERENTIAL DIAGNOSIS:

• Guillain-Barré syndrome (GBS) or CMV infection.

• Leptomeningeal carcinomatosis and lymphoma.

• Chronic inflammatory demyelinating polyneuropathy (CIDP).

• Arachnoiditis from any cause (e.g. post-operative).

• Neurosarcoidosis.

DIAGNOSIS:

Guillain-Barré syndrome (GBS).

PEARLS AND DISCUSSION:

Guillain-Barré syndrome (GBS) is defined as a heterogeneous group of autoimmune polyradiculopathies, involving sensory, motor and autonomic nerves. It is the most common cause of rapidly progressive flaccid paralysis. It is believed to be one of many related conditions, sharing a similar underlying autoimmune abnormality, collectively known as anti-GQ1b IgG antibody syndrome.

The classical presentation of Guillain-Barré syndrome includes symmetrical ascending muscle paresis or palsy, areflexia or hyporeflexia along with a variable degree of sensory or autonomic involvement.

Typical findings in Guillain-Barré syndrome are surface thickening and contrast enhancement on the conus medullaris and the nerve roots of the cauda equine.

The most common site of enhancement in Guillain–Barré syndrome is considered to be anterior nerve roots, although enhancement of the posterior nerve roots is also seen.

FURTHER READING:

1. Fulbright RK, Erdum E, Sze G et-al. Cranial nerve enhancement in the Guillain-Barré syndrome. AJNR Am J Neuroradiol. 1995;16 (4): 923-5. AJNR Am J Neuroradiol (abstract) - Pubmed citation

2. Bassem A. Georgy, MR Imaging of Spinal Nerve Roots: Techniques, Enhancement

3. Patteren And Imaging Findings. AJR 1996, 166:173-179