We present the clinical, imaging and neuropathological findings in three patients with predominant brachial plexus neuropathy. MR scanning was key to determining the brachial plexus involvement. Biopsy of the brachial plexus was performed in one patient. The appearances of the brachial plexus on MRI, in conjunction with the clinical presentations of these patients, suggest that they are unusual variants within the spectrum of chronic inflammatory demyelinating polyradiculoneuropathy.