Perineural spread is a well-known mechanism of dissemination of head and neck malignancies. There are few reports of melanoma involving the brachial plexus in the literature. To their knowledge, the authors report the first known case of perineural spread of malignant melanoma to the brachial plexus. Clinicoradiological and anatomopathological correlation is presented, highlighting the importance of peripheral nerve communications in perineural spread.
Carlos E. Restrepo, Robert J. Spinner, B. Matthew Howe, Mark E. Jentoft, Svetomir N. Markovic and Daniel H. Lachance
Carlos E. Restrepo, Kimberly K. Amrami, Benjamin M. Howe, P. James B. Dyck, Michelle L. Mauermann and Robert J. Spinner
Intraneural perineurioma is a rare, benign slow-growing lesion arising from the perineurial cells that surrounds the peripheral nerve fibers. Typically it presents during childhood and young adulthood as a motor mononeuropathy. MRI plays an essential role in the diagnosis and localization of the lesion, which appears as a fusiform enlargement of the nerve fascicles that enhances intensely with gadolinium. Despite the typical clinical and radiological features, intraneural perineurioma remains largely underdiagnosed because of the lack of familiarity with this entity, but also as a result of technical limitations with conventional MRI that is typically performed as a screening test over a large field of view and without contrast sequences. The purpose of this article is to present the pitfalls and pearls learned from years of experience in the diagnosis and management of this relatively rare condition.
Clinical suspicion and detailed neurological examination followed by high-quality electrophysiological studies (EPS) must lead to an adequate preimaging localization of the lesion and narrowing of the imaging area. The use of high-resolution (3-T) MRI combined with gadolinium administration will allow adequate visualization of the internal anatomy of the nerve and help in differentiating other causes of neuropathy. In cases where the lesion is not recognized but clinical suspicion is high, possible errors must be assessed, including the EPS localization, area of imaging, MRI resolution, and slice thickness.