Ahmad Seif Kanaan1,2, Sarah Gerasch2, Isabel Garcia-Garcia1, Leonie Lampe1, André Pampel1, Alfred Anwander1, Jamie Near3, Kirsten Müller-Vahl2, and Harald E. Möller1
1Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany, 2Department of Psychiatry, Hannover Medical School, Hannover, Germany, 3Douglas Mental Health University Institute and Department of Psychiatry, Mcgill University, Montreal, QC, Canada
We
hypothesized that glutamatergic signalling is related to pathophysiology of
Gilles de la Tourette syndrome (GTS) and investigated glutamatergic metabolism
within cortico-striatal regions using 1H-MRS at baseline and during treatment.
Absolute metabolite concentrations were calculated with the consideration of
voxel compartmentation following frequency and phase drift correction in the
time domain. GTS patients exhibited reductions in striatal and thalamic [Glx],
which were normalized with treatment and were correlated with clinical severity
parameters. Our results implicate glutamatergic metabolism in GTS pathophysiology
and indicate a possibly dysfunctional astrocytic-neuronal coupling system,
which would have profound effects on the dopaminergic modulation of cortico-striatal
input.