MR evaluation of brachial plexus injuries.

Ten cases of brachial plexus injury were subjected to magnetic resonance (MR) to demonstrate the roots, trunks, divisions or cord abnormalities. Both normal and abnormal brachial plexuses were imaged in sagittal, axial, coronal and axial oblique planes. Myelography, using water soluble contrast agents, was performed in seven cases. MR demonstrated one traumatic meningocele, one extradural cerebrospinal fluid (CSF) collection, trunk and/or root neuromas in four, focal root fibrosis in two and diffuse fibrosis in the remaining two cases. Results of MR were confirmed at surgery in four cases with neuromas, while myelography was normal in two and was not carried out in the remaining two. In two cases, where MR demonstrated diffuse fibrosis of the brachial plexus, myelography showed C7 and T1 traumatic meningocele in one and was normal in the other. Both these patients showed excellent clinical and electrophysiological correlation with MR findings and in one of them surgical confirmation was also obtained. In the other two cases with focal nerve root fibrosis, myelography was normal in one and showed a traumatic meningocele in another. Operative findings in these cases confirmed focal root fibrosis but no root avulsion was observed although seen on one myelogram. Focal fibrosis, however, was noted at operation in more roots than was observed with MR. Initial experience suggests that MR may be the diagnostic procedure of choice for complete evaluation of brachial plexus injuries.