The anatomy and pathology of the brachial plexus as demonstrated by computed tomography.

Computed tomography (CT) scanning can demonstrate a wide range of abnormalities affecting both the brachial plexus and the surrounding structures. Narrow section (4 mm) CT was used with bolus intravenous enhancement to examine the root of the neck and axilla in 62 patients with cancer, many of whom had symptoms of brachial plexus neuropathy. The normal anatomy of the plexus and its relations are described and illustrated. Examples of pathological changes caused by tumour and irradiation are also presented. The narrow scanning width (4 mm) is needed as the details sought are small and will be missed on thicker slice widths, particularly the changes of fibrosis in the upper axilla. Injection of intravenous contrast medium is essential for identifying the vascular structures which are used to locate the brachial plexus, especially when disease processes and post-irradiation fibrosis have destroyed the tissue planes.