Characteristic cerebral perfusion patterns in patients with chronic hallucinatory psychosis

Objectives Chronic hallucinatory psychosis (CHP) is defined by chronic hallucinations that are typically multisense and delusional ideas that are relatively well organized and evolved without negative symptoms or intellectual impairment. This study was performed to identify the changes of regional cerebral blood flow in patients with CHP.

Methods Seventeen patients clinically characterized by CHP were involved (M/F = 12/7, 32.3±9.1 y/o). All of the patients suffered with a persistent or intermittent auditory hallucination over 6 months. A Tc-99m ECD brain perfusion SPECT was performed in all patients. Regional cerebral perfusion abnormalities (hypo- or hyperperfusion) were found in SPECT by Statistical Parametric Mapping analysis (version 99, matlab 5.6).

Results During the examinations, none of the patients was referred to a hallucination. In comparison with the healthy subjects, the CHP patients showed significant hypoperfusion in the right superior temporal (BA 38), the right caudate head and the right cerebellar tonsil. Next, in comparison with the healthy subjects, the CHP patients showed significant hyperperfusion in the left temporal gyrus (BA21), the left middle occipital gyrus (BA19), the left putamen, the right precentral (BA 4, 6) gyrus, the right middle frontal gyrus (BA 6, 9), the right inferior frontal gyrus (BA45) and the right paracentral lobule in the right frontal lobe.

Conclusions The SPECT perfusion data showed a decreased perfusion in the right temporal lobe and the right caudate head and an increased perfusion in the left temporal and occipital lobes, the right frontal lobe and the left putamen in the CHP patients. Further investigation about the clinical meaning of the hypo- and hyperperfusion of brain in patients with CHP is needed