Tierärztliche Hochschule Hannover

Manuskript I
creatine, 5 mM lactic acid, 12.5 mM L-glutamic acid, 12.5 mM N-acetyl-L-aspartate
acid, 7.5 mM myo-inositol, 50 mM potassium phosphate, and 0.1% sodium acid as
preservative. The pH was adjusted to 7.03. 18 After preparation of the solution, the
bottle was heated to 37.5°C and positioned in the MRI scanner. Heated gel pads
were placed next to the phantom to preserve the temperature. Standard MRI
protocols for canine brain examinations were used for positioning of the voxel
(Fig. 1).
4.3.3 Magnetic resonance imaging
Images were obtained using a 3.0T Philips Achieva MRI scanner (Philips Medical
Systems Nederland, PC Best, Eindhoven, the Netherlands) in combination with
different phased arrays survey coils: Sensitivity encoding (SENSE)-Flex S (small) coil
with 2 elements, SENSE-Flex M (medium) with 2 elements, SENSE-Flex L (large)
with 2 elements, SENS-Knee coil with 8 elements, SENSE-Spine coil with 15
elements, and SENSE-Neurovascular coil with 16 elements (Philips Medical Systems
Nederland, PC Best, Eindhoven, the Netherlands). When necessary, a combination
of two coils in terms of dual-coil imaging was used in large breed dogs.
T2-TSE-weighted images in dorsal, transversal and sagittal plains were necessary to
position the voxel in unaffected tissue (Fig. 1). For the acquisition of T2-TSE
weighted sequences the following parameters were used: Time to echo (TE): 80-120
milliseconds (msec.), time to repeat (TR): 3000-6000 msec., matrix size of 256x204
for head scans or a matrix size of 448x333 for the thoracic und lumbar spinal cord,
with a slice sickness of 2.2-3.0 millimeter (mm).
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