MR Imaging of the brachial plexus.

MR imaging of the brachial plexus assesses the continuity of the elements, relationship, and orientation of lesions, evaluates morphology, and reveals secondary features of plexopathies. The selection of sequences and imaging planes is guided by the history, clinical examination, and suspected type and location of the abnormality. Increased magnet strength and isotropic imaging with multiplanar reconstructions may allow for standardized imaging protocols and shorter examination time. This article discusses MR imaging evaluation of the brachial plexus, relevant anatomy, and common pathology with clinical and imaging details, indications for use of intravenous contrast, differential considerations, and diagnostic pitfalls.