[Clinical application of brain perfusion SPECT imaging to dementia].

Brain perfusion SPECT imaging has been applied to patients with dementia using 123I-IMP and 99mTc-HM-PAO. Brain blood flow closely parallels regional brain metabolism or brain function with normal cerebrovascular function. Therefore neuronal activity can be indirectly evaluated by in vivo brain perfusion imaging in dementia. This nuclear medicine technique is quite useful for the differential diagnosis, assessment of the degree and localization of the affected area, disease course, and therapeutic effect. IMP seems to be superior to HM-PAO in detecting focal decreased perfusion and quantitative analysis. Hereafter the brain perfusion SPECT study will be more widespread. Neuroreceptor imaging is highly expected as the next step of a brain SPECT study.