Whole-body magnetic resonance neurography in patients with chronic inflammatory demyelinating polyneuropathy.

INTRODUCTION/AIMS: Whole-body magnetic resonance neurography (MRN) is an imaging modality that shows peripheral nerve signal change in patients with chronic inflammatory demyelinating polyneuropathy (CIDP). We aimed to explore the diagnostic potential of whole-body MRN and its potential as a monitoring tool after immunotherapy in treatment-naïve CIDP patients. METHODS: Whole-body MRN using coronal 3-dimensional short tau inversion recovery (STIR) sampling perfection with application-optimized contrasts by using different flip angle evolution (SPACE) techniques was performed in patients being investigated for CIDP and in healthy controls. Baseline clinical neuropathy scales and electrophysiologic parameters were collected, and MRN findings were compared before and after CIDP treatment. RESULTS: We found highly concordant symmetrical thickening and increased T2 signal intensities in the brachial/lumbosacral plexus, femoral, or sciatic nerves in five of the eight patients with a final diagnosis of CIDP and none of the healthy controls. There were no treatment-related imaging changes in five patients with CIDP who completed a follow-up study. Diffuse, symmetrical thickening, and increased T2 signal in root, plexus, and peripheral nerves were found in two patients ultimately excluded due to a diagnosis of polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, skin changes (POEMS) syndrome in addition to signal changes in the muscles, bony lesions, organomegaly, and lymphadenopathy. DISCUSSION: Whole-body MRN imaging shows promise in detecting abnormalities in proximal nerve segments in patients with CIDP. Future studies evaluating the role of MRN in assessing treatment response should consider follow-up scans after treatment durations of more than 4 months.

Effect of Immunosuppression in Risk of Developing Generalized Symptoms in Ocular Myasthenia Gravis: A Retrospective Cohort Study.

BACKGROUNDS AND OBJECTIVES: Early use of immunosuppression has been suggested to prevent generalization of ocular myasthenia gravis (OMG), but high-quality evidence is limited in this regard. We examined whether treatment with prednisone and other immunosuppressants reduce the risk of generalization in OMG. METHODS: This is a retrospective study of consecutive adults with pure OMG who had a minimum 6 months of follow-up. The main outcome was the time to developing generalized symptoms. We used propensity scores to create matched data sets of patients treated with prednisone or any immunosuppressant vs controls. We also used unmatched models with inverse probability of treatment weights (IPTW) and variable exposure times. We used Cox proportional hazards model to estimate hazard ratio (HR) for generalization, comparing treated patients vs controls. RESULTS: A total of 154 patients were included, with a mean follow-up of 87.4 ± 73 months since onset. Forty-three (28%) were generalized, and mean time to generalization from diagnosis was 24.2 ± 24.1 months. Patients who received prednisone had lower risk of generalization than controls, with pooled HR 0.43 (95% CI 0.19-1.06) for the matched model, HR 0.46 (95% CI 0.21-0.89) for the IPTW model, and for HR 0.44 (95% CI 0.23-0.81) for the time-dependent exposure model. Patients who received any immunosuppressant had lower risk of generalization, with HR 0.30 (95% CI 0.11-0.77), 0.32 (95% CI 0.14-0.70), and 0.35 (95% CI 0.15-0.80) for the matched, IPTW, and IPTW-varying exposure models, respectively. DISCUSSION: Our study provides evidence that steroidal and nonsteroidal immunosuppression in patients with OMG is associated with a reduced risk of developing generalized symptoms over time. This supports the early use of immunosuppression in this population. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that treatment of OMG with corticosteroids or nonsteroidal immunosuppressants reduces the risk of generalization.