Tierärztliche Hochschule Hannover

Manuskript I
collies, two Giant schnauzer, two Yorkshire terrier, and one dog of each breed:
Bolonka Zwetna, Dachshund, Elo, French bulldog, French mastiff, Galgo español,
Hanoverian bloodhound, Irish setter, Jack Russell terrier, Maltese, Miniature
schnauzer, Petit basset griffon vendeen, Rottweiler, Samoyed, Tibet terrier, and
Weimaraner. Moreover, seven crossbred dogs were included. The mean age was 6.5
years (range 1-13 years) and the mean body weight was 23 kilogram (range 3 to 43
kilogram). We included 23 male and 24 female dogs in this study. All dogs examined
were patients of the Department of Small Animal Medicine and Surgery, University of
Veterinary Medicine Hannover, Germany, and were presented due to different
neurological disorders. Twentysix patients, with suspected idiopathic epilepsy, did not
reveal structural CNS lesions in the MRI examination, ten displayed a focal brain
lesion, eight were diagnosed with intervertebral disc disease, one with peripheral
nerve sheet lesions, one with an intramedullary spinal cord lesion and one with
polymyositis. The dogs were divided into two groups, independent of age, weight,
gender and underlying disease. The voxel was placed in the brain in 23 of the
patients and in in the spinal cord of 24 patients, respectively. Each dog underwent a
standard MRI examination under general anesthesia (premedication: levomethadone
0.2 mg/kg and diazepam 0.5 mg/kg followed by propofol 1-5 mg/kg to effect,
maintenance with isoflurane and oxygen and continuous monitoring of breathing rate
and blood gases) to diagnose the underlying disease. Dogs with changes in the
spinal cord or brainstem precluding a spectroscopic measurement in unaffected CNS
tissue were excluded. The study was conducted according to the ethical rules of the
University, approved by the promotion Committee, the appointee for animal
protection and received the animal experiment number: 33.9-42502-05-11A190.
4.3.2 Round bottom flask phantom
A phantom was examined to obtain reference peaks of all investigated metabolites
under the same measurement conditions as performed in the dogs. A round glass
bottom flask with one liter of fluid was prepared containing a nearly physiological
composition of brain metabolites as described before: 18 3 mM choline, 10 mM
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