Co-57 SPECT, Tc-99m-ECD SPECT, MRI and neuropsychological testing in senile dementia of the Alzheimer type

Inflammatory mechanisms contribute to the pathophysiology of senile dementi a of the Alzheimer type (sDAT). Previous studies have shown that Co-57 Sing le photon emission computed tomography (SPECT) is able to visualize inflamm atory lesions, probably by means of the final common pathway of Ca2+ homeos tasis disturbance in both neuronal degeneration and inflammation. The aims of this study were: (1) to detect Co-57 SPECT changes in sDAT patients; (2) to correlate these findings with those of conventional neuroimaging techni ques and neuropsychological testing (NPT); and (3) to compare Co-57 SPECT f indings in sDAT patients with those in other types of dementia. Six patient s suffering from probable sDAT were included and compared with four patient s suffering from other types of dementia. All patients had a magnetic reson ance imaging (MRI) scan, NPT, Co-57 and Tc-99m-ethyl cysteinate dimer (ECD) SPECT scan. Perfusion SPECT images were semiquantitatively evaluated by co mparison with an age-matched normal database, while Co-57 SPECT scans were assessed qualitatively. MRI and Tc-99m-ECD SPECT scans yielded conclusive r esults with regard to the exclusion of other pathologies and the confirmati on of the diagnosis. Using visual analysis, Co-57 SPECT scans were unable t o show any regional raised uptake, irrespective of the disorder, depth or e xtent of the perfusion defects, presence of atrophy on MRI or the results o f NPT. ((C) 2001 Lippincott Williams & Wilkins).