Marieke van Rosmalen

Chapter 7 114 We obtained clinical data from electronic patients records, including age; disease duration, defined as months from diagnosis until t 0 ; MRI interval, defined as time in months between t 0 and t 1 ; treatment status (including type of treatment, receiving high dose therapy as start of treatment and need for maintenance therapy); treatment response as documented by the treating physician; and time since last maintenance treatment in days. The Medical Ethical Committee of the University Medical Center Utrecht approved this study. Written informed consent was obtained from all study participants. Figure 7.1 Flow chart of patient selection procedure Participants MRI 1 n = 40 CIDP n = 25 Approved inclusion criteria MRI 2 n = 34 MMN n = 9 Lost to follow up (travel distance) n = 2 MMN n = 7 Lost to follow up (severe illness, and travel distance) n = 2 CIDP n = 23 Abbreviations: MRI = magnetic resonance imaging; CIDP= chronic inflammatory demyelinating polyneuropathy; MMN = multifocal motor neuropathy Equipment and MRI protocol All participants underwent an MRI scan of the brachial plexus at baseline and approximately one year later. We used a 3.0 Tesla MRI scanner (Philips Healthcare, Best, the Netherlands) with a 24-channel head neck coil. Patients were positioned in supine position. We used acquisition parameters as described in a previous study ( Table 7.1 ). 25 In short, we performed a DTI sequence, T2 mapping and T1 Dixon. We used a 3D turbo spin-echo spectral presaturation with inversion recovery as an anatomical reference.