Single photon emission computed tomography in posttraumatic stress disorder before and after treatment with a selective serotonin reuptake inhibitor.

BACKGROUND: Posttraumatic stress disorder (PTSD) is recognized as a disorder mediated by specific neurobiological circuits. Functional imaging studies using script-driven trauma imagery and pharmacological challenges have documented altered cerebral function (activation and deactivation) in several brain regions, including the amygdala, hippocampus, prefrontal cortex and anterior cingulate. However, the neural substrates of PTSD remain poorly understood and the effect of selective serotonin reuptake inhibition on regional cerebral activity is deserving of further investigation. METHODS: Eleven adult patients (seven men, four women) (mean age+S.D.=33.6+/-9.2 years) with a DSM-IV diagnosis of PTSD, as determined by the Structured Clinical Interview for DSM-IV (SCID-I) and the Clinician-Administered PTSD Scale (CAPS), underwent single photon emission computed tomography (SPECT) with Tc-99m HMPAO pre- and post-8 weeks of treatment with the selective serotonin reuptake inhibitor, citalopram. Symptoms were assessed at baseline and at 2-week intervals with the Clinician-Administered PTSD Scale (CAPS), Montgomery-Asberg Depression Rating Scale (MADRS), and the Clinical Global Impression Scale (CGI). Image analysis of baseline and post-treatment scans was performed using Statistical Parametric Mapping (SPM). RESULTS: Treatment with citalopram resulted in significant deactivation in the left medial temporal cortex irrespective of clinical response. On covariate analysis, a significant correlation between CAPS score reduction and activation in the left paracingulate region (medial prefrontal cortex) was observed post-treatment. No significant pre-treatment differences were observed between responders and non-responders in anterior cingulate perfusion. CONCLUSIONS: These preliminary findings are consistent with clinical data indicating temporal and prefrontal cortical dysfunction in PTSD and preclinical data demonstrating serotonergic innervation of these regions. However, further studies, in particular in vivo receptor imaging studies, are needed to confirm whether these regional abnormalities correlate with clinical features and treatment response.

Functional brain imaging and pharmacotherapy in trichotillomania. Single photon emission computed tomography before and after treatment with the selective serotonin reuptake inhibitor citalopram.

The neurobiology and pharmacotherapy of trichotillomania has received increasing attention in recent years. Parallels have been drawn between findings in this disorder and those in obsessive-compulsive disorder (OCD). To date, however, there has been little work on the effect of a pharmacotherapeutic intervention on functional brain imaging in trichotillomania. Female patients (n = 10) with DMS-IV diagnostic criteria for trichotillomania were subjected to single photon emission computed tomography (SPECT) with technetium-99m hexamethylpropylene amine oxime (Tc-99m HMPAO) before and after 12 weeks of pharmacotherapy with the selective serotonin reuptake inhibitor (SSRI), citalopram. Pharmacotherapy led to significantly reduced activity in inferior-posterior and other frontal regions. Correlates of hair-pulling symptoms with regional brain activity differed before and after pharmacotherapy. These data are to some extent consistent with work suggesting that trichotillomania, like OCD, is mediated by corticostriatal circuits. Pharmacotherapeutic response to SSRIs in trichotillomania may not be as robust as in OCD. Further research is necessary to determine the neurobiological underpinnings of these differences.

SPECT scans in identical twins with trichotillomania.

SPECT scans of a set of twins with trichotillomania showed that the twin with more severe disease had larger perfusion defects, involving more areas on the scan. Prospective brain imaging studies of twins may provide useful information about the neurobiology of trichotillomania and other obsessive-compulsive spectrum disorders.

Childhood trauma in obsessive-compulsive disorder, trichotillomania, and controls.

There is relatively little data on the link between childhood trauma and obsessive-compulsive/putative obsessive-compulsive spectrum disorders. The revised Childhood Trauma Questionnaire (CTQ), which assesses physical, emotional, and sexual abuse as well as physical and emotional neglect, was administered to female patients with obsessive-compulsive disorder (OCD; n = 74; age: 36.1 plus minus 16.3), TTM (n = 36; age: 31.8 plus minus 12.3), and a group of normal controls (n = 31; age: 21.5 plus minus 1.0). The findings showed a significantly greater severity of childhood trauma in general, and emotional neglect specifically, in the patient groups compared to the controls. Although various factors may play a role in the etiology of both OCD and trichotillomania (TTM), this study is consistent with some evidence from previous studies suggesting that childhood trauma may play a role in the development of these disorders.