[Brain photon emission tomography. Value of the corticocerebellar index and gammagraphic patterns in Alzheimer's disease and other diseases].

Brain single photon emission computed tomography (SPECT) with 99mTc-HMPAO is a diagnostic tool for evaluating regional cerebral blood flow. Recently, the diagnostic possibilities of the method are being investigated in some neurologic disorders, such as cerebrovascular accidents, seizures and dementia. This work has been carried out with 54 subjects, 9 healthy volunteers and 45 patients (31 dementia and 14 epileptics), in order to evaluate gammagraphic patterns and the utility of cortico/cerebellar activity indexes. An interesting diagnostic finding is a significant decrease (p less than 0.001) in perfusion of temporoparietal regions in the patients with Alzheimer's disease in relation with the healthy volunteers' group. We have not found significant changes in perfusion in the group of epileptic patients during the interictal phase. We conclude emphasizing the interest of the SPECT in the differential diagnosis of dementia.