To describe the normal structure, anatomical location and branching pathways of the brachial plexus by correlating structures on ultrasound (US) and magnetic resonance imaging (MRI). To present a standard US examination and MRI protocol for the brachial plexus. To compare the US and MRI by outlining the advantages and disadvantages of each technique.

In the last decades, the imaging of the peripheral nerves has become a rising field of research in medicine. Pain in the neck and head area is one of the most common manifestations of the brachial plexus pathology. In the last years, the golden standard in brachial plexus imaging has been MRI but due to new advancements in US technology, the US is quickly gaining recognition. It is our goal to evaluate the advantages/disadvantages of both imaging methods.

Anatomy The brachial plexus stems from the cervical spinal cord and extends to the axillary region to form the nerves that control movement in the upper limbs [1]: The brachial plexus is divided into roots, trunks, divisions, cords and branches (Fig. 1) 5 roots: formed from cervical nerves (C5 to C8) and the first thoracic nerve (T1) 3 trunks: ventral rami of roots form superior (C5, C6), middle (C7) and inferior (C8, T1) trunk 6 divisions: each trunk splits into two forming anterior divisions of...

US should be used as a primary modality in diagnostic workup in brachial plexus and may be complemented with the MRI of the brachial plexus region. A combination of both imaging modalities increases the diagnostic sensitivity for the brachial plexus pathology.

V. Potočnik Tumpaj; Ljubljana/SI - nothing to disclose Z. Snoj; Ljubljana/SI - nothing to disclose A. Sirnik; Ljubljana/SI - nothing to disclose

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