Brain Perfusion Abnormalities in Gilles de la Tourette's Syndrome

Abstract

BackgroundFunctional brain imaging with technetium-99m d,l-hexamethyl propyleneamine oxime (HMPAO) Single Photon Emission Tomography (SPET) allows us to explore the cerebral pathophysiology of Gilles de la Tourette's Syndrome (GTS).MethodFifty patients and 20 controls were examined. Patients were rated for tic severity and mood. Scans were analysed quantitatively using internal ratios to the occipital cortex.ResultsPatients differed from controls on measures of relative blood flow to the left caudate, anterior cingulate cortex and the left dorsolateral prefrontal cortex. Severity of tics was related to hypoperfusion of the left caudate and cingulate and a left medial temporal region. Hypoperfusion in the left dorsolateral prefrontal region was related to mood.ConclusionsThe areas found to be hypoperfused in this study are consistent with known functions of fronto-striatal circuits. A wide range of perfusion patterns is seen, however, and no characteristic patterns for behavioural subgroups has been documented with this technique.