J Korean Neurotraumatol Soc.  2010 Dec;6(2):106-109. 10.13004/jknts.2010.6.2.106.

Usability of Magnetic Resonance Neurography for Diagnosis of Neuralgic Amyotrophy in Acute Stage

• Yang JS
• Cho YJ
• Yu DK
• Heo DH
• Sheen SH
• Hwang G
• Park SH

• KMID: 2106794
• DOI: http://doi.org/10.13004/jknts.2010.6.2.106

Abstract

OBJECTIVE
Neuralgic amyotrophy (NA) is a distinct clinical syndrome of unknown etiology involving the brachial plexus, which is characterized by the acute onset of shoulder and arm pain followed by weakness, and sensory loss. Diagnosis with neurophysiologic studies and a conventional MRI of brachial plexus is very difficult in acute stage. The magnetic resonance neurography (MRN) is considered to be more sensitive than MRI for the peripheral neuropathies. The objective of this study is to describe the MRN findings and its usability for patients with neuralgic amyotrophy in acute stage.
METHODS
The authors have treated 10 patients with NA between 2006 and 2009. All the patients had clinical and neurophysiologic evidence of acute brachial plexopathy without a definable cause. Recently, three patients were evaluated in acute stage using a MRN with a 1.5-T scanner and had positive findings for NA. Imaging sequences for brachial plexus included axial, sagittal, and coronal conventional spin echo sequences, and gadolinium was administered for axial and coronal images, employing short tau inversion recovery sequences.
RESULTS
All patients were checked the brachial plexus MRN within 3 weeks after onset. In conventional MRI, the authors did not find any evidences of plexopathy, mass lesion, muscle atrophy or rotator cuff tear. However, brachial plexus MRN of all the patients showed thickened and hyperintense trunks of the brachial plexus in lesion site consistent with plexitis.
CONCLUSION
MRN is the most specific diagnostic modality especially in acute stage of NA. It can help early diagnosis and prevent unnecessary studies.

Keyword

Neuralgic amyotrophy; Brachial plexus; Diagnosis; Magnetic resonance imaging

MeSH Terms

Arm
Brachial Plexus
Brachial Plexus Neuritis
Brachial Plexus Neuropathies
Early Diagnosis
Gadolinium
Humans
Magnetic Resonance Imaging
Magnetic Resonance Spectroscopy
Magnetics
Magnets
Muscular Atrophy
Peripheral Nervous System Diseases
Rotator Cuff
Shoulder
Gadolinium