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Updated: Jan 24, 2026

Ultrasound Assessment of Endothelial-Dependent Flow-Mediated Vasodilation of the Brachial Artery in Clinical Research
Published on: October 22, 2014
A prospective study of high resolution ultrasound in brachial plexopathies - Correlation with electrophysiological
Rune Lau Jakobsen1, Anders Fuglsang-Frederiksen1, Michel Bach Hellfritzsch2
1Department of Neurophysiology, Aarhus University Hospital, Denmark.
Objectives:
To evaluate the diagnostic role of ultrasound in brachial plexopathies.
Methods:
We included 59 healthy subjects (HS) and 42 patients consecutively referred with clinical suspicion of brachial plexopathy from October 2015 to May 2016. Patients underwent routine electrodiagnostic testing (EDx) as reference standard and a blinded standardised ultrasound examination of the brachial plexus as index test with cross-sectional area (CSA) as the ultrasound parameter of choice.
Results:
Seventeen patients were diagnosed by EDx with brachial plexopathy, ten with mononeuropathies, and ten had normal EDx. Five had a cervical radiculopathy. In 11 (64%) out of the 17 patients with EDx diagnosed plexopathy, we found at least one abnormal level on ultrasound. Six (60%) out of ten normal EDx patients had a normal ultrasound examination at all levels. Ultrasound identified the same abnormal level(s) as EDx in eight (73%) of the 11 patients who had both abnormal EDx and ultrasound results. Mean CSA was higher in the plexopathy group compared to HS at the level of the C6 root (p = .022), the middle trunk (p = .027), and the medial cord (p = .003).
Conclusion:
Ultrasound examination showed abnormalities in patients with brachial plexopathies in good agreement with EDx.
Significance:
Ultrasound may be an important supplement to electrodiagnostics in evaluating brachial plexopathies.
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