Use of Magnetic Resonance Neurography for Evaluating the Distribution and Patterns of Chronic Inflammatory Demyelinating Polyneuropathy

Objective: To evaluate the distribution and characteristics of peripheral nerve abnormalities in chronic inflammatory demyelinating polyneuropathy (CIDP) using magnetic resonance neurography (MRN) and to examine the diagnostic efficiency.Materials and Methods: Thirty-one CIDP patients and 21 controls underwent MR scans.Three-dimensional sampling perfections with application-optimized contrasts using different flip-angle evolutions and T1-/T2-weighted turbo spinecho sequences were performed for neurography of the brachial and lumbosacral (LS) plexus and cauda equina, respectively.Clinical data and scores of the inflammatory Rasch-built overall disability scale (I-RODS) in CIDP were obtained.Results: The bilateral extracranial vagus (n = 11), trigeminal (n = 12), and intercostal nerves (n = 10) were hypertrophic.Plexus hypertrophies were observed in the brachial plexus of 19 patients (61.3%) and in the LS plexus of 25 patients (80.6%).Patterns of hypertrophy included uniform hypertrophy (17 [54.8%] brachial plexuses and 21 [67.7%]LS plexuses), and multifocal fusiform hypertrophy (2 [6.5%] brachial plexuses and 4 [12.9%]LS plexuses) was present.Enlarged and/or contrast-enhanced cauda equina was found in 3 (9.7%)and 13 (41.9%)patients, respectively.Diameters of the brachial and LS nerve roots were significantly larger in CIDP than in controls (p < 0.001).The largest AUC was obtained for the L5 nerve.There were no significant differences in the course duration, I-RODS score, or diameter between patients with and without hypertrophy.Conclusion: MRN is useful for the assessment of distribution and characteristics of the peripheral nerves in CIDP.Compared to other regions, LS plexus neurography is more sensitive for CIDP.