Improvement of Somatic Delusions with Altered Regional Cerebral Blood Flow Following Electroconvulsive Therapy in a Patient with Schizoaffective Disorder

Objective: Unusual or unexpected effect of treatment Background: Somatic delusions are false and fixed beliefs about health and organ function, which are observed in various psychiatric disorders. Psychotropic drugs such as antipsychotics and antidepressants are effective for some patients, while the efficacy of electroconvulsive therapy (ECT) for pharmacotherapy-resistant cases has been reported. Previous reports suggest that somatic delusions in delusional disorder somatic type are associated with reduced regional cerebral blood flow (rCBF), but it remains unclear whether this association is also observed in other psychiatric disorders. We report the case of a patient with schizoaffective disorder whose drug-resistant somatic delusions showed remarkable improvement accompanied by altered rCBF after successful ECT. Case Report: The patient was a Japanese man aged 52 years with a diagnosis of schizoaffective disorder. He was suffering from severe and persistent somatic delusions such as "There is a thick stick or bowl in my head" and "Something like a film stretches over my head and face", which were resistant to several antipsychotics and antidepressants. In our hospital, he received bitemporal ECT 8 times. His somatic delusions started to improve from the third administration, and they disappeared by the eighth administration. In parallel with this clinical improvement, reduction of rCBF in the bilateral parietal and occipital lobes observed before ECT disappeared. Conclusions: The present study suggests that ECT is a useful choice for drug-resistant somatic delusions. Reduction of rCBF in the bilateral parietal and occipital lobes may be associated with manifestation of somatic delusions in schizoaffective disorder.