ABNORMAL REGIONAL BENZODIAZEPINE RECEPTOR UPTAKE IN THE PREFRONTAL CORTEX IN PATIENTS WITH PANIC DISORDER

The neuroanatomical networks involved in the initiation of panic attac k and the maintenance of panic disorder are poorly understood. This st udy aimed to elucidate the possible abnormalities in benzodiazepine re ceptor uptake in the brain of patients with panic disorder. Seventeen unmedicated patients with panic disorder were investigated using I-123 -iomazenil single photon emission tomography (SPET). Seventeen healthy age- and sex-matched volunteers served as controls. The SPET scan was taken 90 min after injection of tracer. Eleven of 17 patients (65%) s howed an increased (>2 S.D. higher than the mean of the controls) righ t-to-left ratio of benzodiazepine receptor uptake in the prefrontal co rtex. Also, the mean right-to-left ratio of benzodiazepine receptor up take in all 17 patients with panic disorder was higher than in the con trols (P<0.001). Our SPET study demonstrated focally altered benzodiaz epine receptor uptake in the prefrontal cortices in patients with pani c disorder. Magnetic resonance imaging indicated that the affected reg ion was located in the right middle and inferior frontal gyri. The det erioration in information processing in the right prefrontal cortex ma y be implicated in the generation of panic disorder.