Prefrontal cortical sulcal widening associated with poor treatment response to clozapine

Increased sulcal widening in the prefrontal cortex of patients with schizophrenia may be associated with a poor treatment response to clozapine. To further evaluate this, we examined data from patients treated with clozapine in our center. Patients with the greatest degree of improvement (n=26) and those with no improvement (n=10) were compared. Computerized tomography (CT) scans were rated blindly on a visual scale of prefrontal sulcal widening. Patients with the greatest degree of functional improvement had significantly less prefrontal sulcal widening than those whose symptoms remained unchanged. There was no relationship between clozapine response and general sulcal widening. These data support the link between the superior therapeutic efficacy of clozapine and the integrity of the prefrontal cortex.