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Updated: Jan 24, 2026

Nerve Ultrasound Protocol to Detect Dysimmune Neuropathies
Published on: October 7, 2021
Ultrasound in Multifocal Motor Neuropathy: Clinical and Electrophysiological Correlations
Ari Breiner1, Hamid Ebadi2, Vera Bril3,4
1Department of Medicine (Neurology), The Ottawa Hospital, The Ottawa Hospital Research Institute, University of Ottawa, Ottawa, ON, Canada.
Objectives:
Multifocal motor neuropathy (MMN) is a treatable autoimmune polyneuropathy, which may prove challenging diagnostically in the setting of absent conduction blocks or advanced axonal loss. Relatively few studies have examined the role of ultrasound (US) in MMN.
Methods:
Retrospective, cross-sectional study of patients with MMN who underwent peripheral nerve US. Charts were reviewed to extract clinical, sonographic, and electrophysiological data.
Results:
Eleven patients with MMN underwent US between 2013 and 2015; of these 11 patients, 7 had ≥3 abnormal nerve segments, and 6 had ≥5 sites of increased cross-sectional area (CSA). There was moderate correlation between the degree of amplitude drop observed in the median and ulnar motor nerves, and CSA. Significant correlation between CSA and limb strength was only observed for the median nerve.
Conclusions:
Peripheral nerve US shows promise as a diagnostic tool in MMN and may be helpful to distinguish MMN from motor neuron disease.
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