Marieke van Rosmalen

Chapter 6 98 RESULTS Participants and clinical data We enrolled 137 participants based on the in- and exclusion criteria. We had to exclude 11 more patients: 2 patients (1.5%) because of claustrophobia during scanning, 2 patients (1.5%) because of a changed diagnosis after inclusion, 1 patient (0.7%) due to movement artifacts that led to low data quality and an additional 6 patients (4.4%; CIDP = 3, MMN = 1, controls = 2) after processing and tract segmentation due to insufficient data quality. We used data from 126 study participants for further analysis (CIDP = 47, MMN = 29, MND = 40 (ALS = 19, PMA = 21), healthy controls = 10). The patient characteristics are summarized in Table 6.2 . Patients with MMN were younger than patients with CIDP and PMA ( p < 0.001). Other characteristics did not differ significantly between groups. Table 6.2 Patient characteristics Parameter Inflammatory neuropathy Motor neuron disease Healthy controls p value CIDP MMN ALS PMA Number of participants 47 29 19 21 10 Age, years (SD) 64.0 (9.6) 53.7 (11.2) 60.4 (12.3) 65.2 (10.4) 57.4 (7.3) <0.001* Male (%) 39 (83.0%) 27 (93.1%) 12 (63.2%) 18 (85.7%) 7 (70%) 0.088 Disease duration, months (SD) 34.5 (67.1) 65.1 (82.3) 30.8 (24.3) 57.5 (45.4) - 0.100 MRC sum score (SD) 111.9 (10.1) 113.8 (4.6) 110.6 (7.9) 107.5 (11.2) - 0.119 *Age differs significantly between patients with MMN and patients with CIDP, and between patients with MMN and patients with PMA. Age, disease duration and MRC sum score are mean. Abbreviations: CIDP = chronic inflammatory demyelinating polyneuropathy; MMN = multifocal motor neuropathy; ALS = amyotrophic lateral sclerosis; PMA = progressive muscular atrophy; SD = standard deviation; MRC = Medical Research Council. Semi-automated data processing After automated processing, we identified 92.9% of all nerve roots (93.3%, 98.4% and 86.9% for C5, C6 and C7 respectively), which increased to 96.0% of C5 nerve roots, 99.6% of C6 nerve roots and 95.6% of C7 after additional manual adjustments. Quantitative MRI parameters Diffusion parameters, T2 relaxation times and fat fraction did not differ between right and left side of the nerve roots, except for FA in nerve root C7 ( p < 0.001). This only significant finding did not influence our data and we therefore decided to combine right and left sides in further analysis.