Brain Magnetic Resonance Imaging and Magnetic Resonance Spectroscopy in TS

Grant Type
Grant Year
Institution Location
Institution Organization Name
University of Western Ontario Canada
Investigators Name
Nicolson, Rob, MD

A number of volumetric and functional brain imaging studies suggest abnormalities in brain circuits involving the cortex, striatum, and thalamus as possible causes of TS. However, the abnormalities of neurons (brain cells) within these brain structures are unknown. Through the measurement of N-acetylaspartate (NAA), a neuronal marker, proton magnetic resonance spectroscopy (MRS) provides a unique opportunity for the in vivo investigation of neuronal abnormalities in these regions. However, there have been, to date, no published studies of NAA or proton MRS in TS. Funded by TSA, pilot data from our initial MRS study suggest neuronal abnormalities in the caudate nucleus and frontal lobes and a lack of the asymmetry seen in the caudate nucleus and frontal gray matter. The objective of the present study is to confirm and extend these findings in TS using magnetic resonance imaging and magnetic resonance spectroscopy. Children and adolescents with TS and a control group of children without tics or other major psychiatric illness will undergo magnetic resonance scanning on a 3 Tesla head only magnetic resonance scanner. Frontal gray and white matter volumes and the volume of the basal ganglia and the thalamus will be measured on magnetic resonance images using semiautomated techniques. Magnetic resonance spectroscopy will be used to determine the concentration of NAA in these regions. We hypothesize a reduction in volume of both frontal gray matter and caudate nucleus, abnormalities of NAA in these regions and a lack of normal asymmetry of the caudate nucleus, all of which suggest neuronal abnormalities. If these hypotheses are confirmed, the findings would further our knowledge of the neurobiological basis of TS, and may ultimately be important in determining more effective treatments for tics. Rob Nicolson, M.D., Peter Williamson, M.D., Dick Drost, Ph.D., Dept. of Psychiatry, University of Western Ontario, London, Ontario, Canada Award: $60,000 This study was funded through the generosity of Randi Zemsky and Shirley and Sam Zemsky Tourette Association of America Inc. – Research Grant Award 2003-2004