Magnetom trio mr scanner

The recordings were performed in a 3-T Siemens Magnetom Trio MR Scanner (Siemens, Erlangen, Germany) with a 12-channel head coil. The functional T2*-weighted MR images were acquired with an echo planar imaging (EPI) sequence. The characteristics of the sequence were 250 and 406 volumes for the resting state and the Sternberg WM task, respectively, 35 slices, 3 mm × 3 mm × 3 mm, matrix size 64 × 64, FOV 192 mm × 192 mm, TR/TE = 1960 ms/30 ms.
The structural T1-weighted sequence (ADNI) had following parameters: 176 sagittal slices, slice thickness 1.0 mm, voxel size 1 mm × 1 mm × 1 mm, FOV 256 mm × 256 mm, TR/TE = 2300 ms/2.98 ms.
Preprocessing of the functional MRI data was done in SPM8 (Welcome Department of Imaging Neuroscience, London).¹ First, slice time correction was performed, and the data were motion corrected to the mean image. Then, the anatomical T1 was coregistered to the mean image, followed by its segmentation into six tissue probability maps. Finally, the data were normalized and smoothed using an FWHM kernel of 6 mm × 6 mm × 6 mm.

The images were collected at 3T on a Magnetom TRIO MR scanner (Siemens Medical Systems, Erlangen, Germany) with an eight-channel PA head coil for radio-frequency transmission and signal reception. Whole brain functional images were acquired using a T2*-weighted sequence sensitive to BOLD contrast; 664 for the main experiment and 107 for the localizer task (EPI: TR = 2630 ms, TE = 35 ms, 40 axial slices, image matrix  = 64×64, FOV = 224 mm, flip angle  = 80°, voxel size  = 3.5×3.5×3.5 mm). A 3-D high-resolution T1-anatomical image of the whole brain was also obtained for coregistration with the functional images (3-D MPRAGE: TR  = 1550 ms, TE  = 2.39 ms, TI  = 900 ms, 176 sagittal slices, acquisition matrix  = 256×256, FOV  = 220 mm, flip angle  = 9°, voxel size  = 0.9×0.9×0.9 mm).

Twenty patients with idiopathic cervical dystonia were initially recruited for this study. Datasets from three patients were discarded due to movement artifacts, so the analysis comprised 17 patients (nine females). All patients received botulinum toxin A as part of their regular treatment. The degree of disability was rated using the Tsui Scale (31 (link)). Furthermore, 29 age- and gender-matched healthy subjects participated in the study (15 females). The approval by the institutional ethics committee (Ethik-Kommission des Fachbereichs Medizin der Goethe-Universität Frankfurt am Main, Germany) was obtained and all participants gave their written informed consent before taking part in the study.
The MRI acquisition was performed on a 3-Tesla whole body scanner (Magnetom TRIO MR scanner, Siemens Medical Solutions, Erlangen, Germany), equipped with an 8-channel phased-array head coil for signal reception and a body coil for radio frequency (RF) transmission.
The following measures were taken to reduce movement artifacts: Scans were conducted ~2 weeks after the last treatment with botulinum toxin when satisfactory treatment effects were already present in most patients. None of the examined patients suffered from severe head tremor. Furthermore, the head was comfortably bolstered in the coil to reduce movements.