Cavum septi pellucidi in Tourette syndrome

Background An enlarged cavum septum pellucidum (CSP) is a putative marker of disturbed brain development, and it has been associated with a variety of neuropsychiatric disorders. The goal of this study was to characterize systematically the CSP and the related cavum vergae in individuals with Tourette syndrome (TS). Methods The overall size and anteroposterior length of the CSP in 161 children (97 with TS and 64 normal pediatric control subjects) and 107 adults (43 with TS and 64 normal adult control subjects) were rated on high-resolution magnetic resonance images in the coronal view. The associations of CSP size with diagnosis and symptom severity scores were assessed using ordinal logistic regression. Results CSP size in TS children was significantly smaller than in normal control subjects, and it was inversely associated with attention-deficit/hyperactivity disorder symptom severity in the TS subjects. CSP size was not significantly associated with the comorbid diagnoses of OCD or ADHD. These results were replicated in the independent sample of adults with TS and their same-age control subjects. The presence of a cavum vergae was not significantly associated with a diagnosis of TS. Conclusions These findings suggest that the pathophysiology of TS may involve abnormalities in the early development of the CSP or in the neighboring corpus callosum, septal nuclei, or limbic system.