Hideo Ohnishi

Regional cerebral blood flow in catatonic schizophrenia

Single photon emission computed tomography (SPECT) with 123I-iodoamphetamine (IMP) as tracer was used to study regional cerebral blood flow (rCBF) distribution in six patients with the catatonic subtype of schizophrenia (DSM-III-R). IMP-SPECT imaging revealed a significant reduction of rCBF in the parietal lobes of both hemispheres. Three-dimensional reconstruction of the SPECT images identified the superior region of the frontoparietal lobe as the most severely affected region. The pattern of rCBF deficits observed in catatonic schizophrenia differs markedly from that seen in 13 patients with other subtypes of schizophrenia and 7 normal control subjects. These observations indicate that parietal lobe dysfunction may be an important component in the pathology of the catatonic subtype of schizophrenia.

Relationship between skeletal uptake of99mTc-HMDP and bone mineral density in elderly women

The relationship between bone mineral density in elderly women and the pattern of skeletal uptake of99mTc-HMDP, especially in regard to skull uptake, was investigated.The whole-body skeletal uptake (WBSU) and whole-body skeletal tracer distribution patterns were studied in 86 disease-free women on bone scintigraphy with99mTc-hydroxy-methylene-diphosphonate (HMDP). Bone scans were quantified by setting regions of interest (ROI) and bone mineral density (BMD) was assessed by dual-energy X-ray absorptiometry in all patients. WBSU and the skeletal distribution pattern were compared with bone mineral densities of the entire skeleton as well as selected regions.WBSU was high in the elderly and negatively correlated with regional bone mineral densities (r = −0.403 to −0.534). Among the regions, uptake by the skull increased with age more than in other regions in women and had the highest negative correlation with the bone mineral density. The skull uptake correlated negatively with total body BMD (r = −0.583) and with lumbar BMD (r = −0.561, p< 0.0001).Our results show that increased radionuclide uptake in bone scintigraphy, especially skull uptake was associated with decreased bone mineral density in elderly women, so that, increased skull uptake in elderly women would be a scintigraphic sign of post-menopausal or senile osteopenia.