Single Photon Emission Computed Tomography in Alzheimer's Disease

Cerebrovascular Reactivity to Acetazolamide in (Senile) Dementia of Alzheimer’s Type: Relationship to Disease Severity

“…These data did not differ from the mean values of the reactivity in the ROIs of each patient [data not given here]. Our method is similar to that of other authors concerning resting values [1][2][3][4] and measurement of cerebrovascular reactivity [23].…”

“…Alterations of cerebral blood flow (CBF) in (senile) dementia of Alzheimer's type [(S)DAT] have been shown in many studies [1][2][3][4], Because the hypoperfusional pat tern with bilateral, often asymmetrical parietooccipital and temporal deficits [1][2][3][4][5][6][7] was similar to that of reduc tion of glucose metabolism and neuropathological in volvement of different brain areas, the current opinion is that CBF follows brain function in this disease [8,9]. This is also underlined by longitudinal studies, demonstrating that CBF is reduced before the onset of vascular dementia but follows the onset of (S)DAT [10,11], and by parallel studies with l50 -and 18F-deoxyglucose and positron Accepted: August 24.…”

“…There were trends for a negative correlation between cerebrovascular reactivity (CVR) and the depres Since arteriosclerosis has not been proved to be the rea son for dementia of Alzheimer's type, only little research focused on cerebrovascular problems in this disease. Pre vious studies concerning resting CBF showed normal or reduced global CBF and hypoperfusional foci in those regions, which are known to be most involved in the dis ease process (temporoparietooccipital cortex) [1][2][3][4], These patterns were similar to the results of PET studies of cerebral glucose metabolism using fluorodeoxyglucose [5][6][7][8][9]. The resting values of our patients show either unior bilateral parietooccipital or frontoparietal hypoperfu sion and are below that of the control group, and therefore confirm these results.…”

Longitudinal Cerebral Perfusion Decrease in Mild Alzheimer’s Disease Revealed by SPECT with Statistical Parametric Mapping Method

“…However, SPECT investigations have typically demonstrated perfusion changes in the posterior cingulate gyrus or parietal cortical region in early AD [5, 7, 8], and parietotemporal regions in later-stage AD [1, 2]. These discrepancies between structural and perfusion studies may be due to the fact that perfusion changes demonstrated by SPECT can result not only from neuron loss but also from decreased synaptic activity of dysfunctional neurons in another brain region.…”

“…Single photon emission computed tomography (SPECT) is the most widely used functional neuroimaging technique in clinical practice. SPECT studies have demonstrated cerebral perfusion deficits in AD, typically in the temporoparietal areas [1, 2]. Other factors to consider in interpretation of SPECT images include the age of the patient [3], age at disease onset [4], disease severity [5], education [6], apolipoprotein E polymorphism [7], and imaging methodology.…”