Magnetic resonance neurography (also called MRN or MR neurography) refers to MR imaging dedicated to the peripheral nerves. It is a technique that enhances selective multiplanar visualisation of the peripheral nerve and pathology by encompassing a combination of two-dimensional, three-dimensional and diffusion imaging pulse sequences. Referring physicians who seek imaging techniques that can depict and diagnose peripheral nerve pathologies superior to conventional MR imaging are driving the demand for MRN. This article reviews the pathophysiology of peripheral nerves in common practice scenarios, technical considerations of MRN, current indications of MRN, normal and abnormal neuromuscular appearances, and imaging pitfalls. Finally, the emerging utility of diffusion-weighted and diffusion tensor imaging is discussed and future directions are highlighted.
Key points: • Lesion relationship to neural architecture is more conspicuous on MRN than MRI. • 3D multiplanar imaging technique is essential for pre-surgical planning. • Nerve injuries can be classified on MRN using Sunderland's classification. • DTI provides quantitative information and insight into intraneural integrity and pathophysiology.
Keywords: DTI; MR neurography; MRI; MRN; Peripheral nerve.