HMPAO SPET does not distinguish obsessive-compulsive and tic syndromes in families multiply affected with Gilles de la Tourette's syndrome.

Background: Gilles de la Tourette's syndrome (GTS) is a familial neuropsychiatric disorder characterized by tics and obsessive-compulsive behaviours (OCB). Previous HMPAO SPET studies of subjects with GTS have shown hypoperfusion of striatal and frontal areas. Studies of patients with primary obsessive-compulsive disorder have shown, in contrast, hyperperfusion of similar areas.
Methods: Twenty subjects from five families affected by GTS, including individuals with OCB but no tics, were examined using HMPAO SPET.
Results: There were abnormalities of regional cerebral perfusion in individuals with GTS, OCB and tics. Hypoperfusion was in striatal, frontal and temporal areas. There was no hyperperfusion.
Conclusions: Regional cerebral blood flow patterns in individuals with OCB in families affected by GTS are comparable to their relatives with GTS and differ from individuals with primary OCD in the absence of a family history of tic disorders.