TC-99m HMPAO Brain Blood Flow Imaging in the Dementias with Histopathologic Correlation in 73 Patients

The purpose of this study is to determine the value of Tc-99m HMPAO SPECT in the diagnosis of the dementias. Tc-99m HMPAO was used with a 3-camera scanner to produce 5 sets of sectional images of the brain. Images were further processed using Statistical Parametric Mapping. Diagnosis was made by a physician blinded to the clinical diagnosis. Results in 73 subjects were compared with a neuropathologic study of the brain at autopsy. Data were analyzed for sensitivity, specificity, positive and negative predictive values and accuracy. These results are compared with several other studies performed with Tc-99m HMPAO SPECT with histopathologic correlation. This procedure is widely available and relatively inexpensive and may be of value in patients with dementias and problematic diagnoses. Further, a degree of differential diagnosis between Alzheimer's and Frontotemporal diseases may be effected. The study was approved by our Institutional Review Board

Nanoparticulate Radiolabelled Quinolines Detect Amyloid Plaques in Mouse Models of Alzheimer's Disease

Detecting aggregated amyloid peptides (Aβ plaques) presents targets for developing biomarkers of Alzheimer's disease (AD). Polymeric n-butyl-2-cyanoacrylate (PBCA) nanoparticles (NPs) were encapsulated with radiolabelled amyloid affinity 125I-clioquinol (CQ, 5-chloro-7-iodo-8-hydroxyquinoline) as in vivo probes. 125I-CQ-PBCA NPs crossed the BBB (2.3 ± 0.9 ID/g) (P < .05) in the WT mouse (N = 210), compared to 125I-CQ (1.0 ± 0.4 ID/g). 125I-CQ-PBCA NP brain uptake increased in AD transgenic mice (APP/PS1) versus WT (N = 38; 2.54 × 105 ± 5.31 × 104 DLU/mm2; versus 1.98 × 105 ± 2.22 × 104 DLU/mm2) and in APP/PS1/Tau. Brain increases were in mice intracranially injected with aggregated Aβ42 peptide (N = 17; 7.19 × 105 ± 1.25 × 105 DLU/mm2), versus WT (6.07 × 105 ± 7.47 × 104 DLU/mm2). Storage phosphor imaging and histopathological staining of the plaques, Fe2+ and Cu2+, validated results. 125I-CQ-PBCA NPs have specificity for Aβ in vitro and in vivo and are promising as in vivo SPECT (123I), or PET (124I) amyloid imaging agents

Single-photon Emission Tomography (SPECT) in the Study of Aphasia: A Preliminary Report

TB

Tomographic Regional Cerebral Blood Flow Activation During Phoneme Detection in Normal and Aphasic Subjects

TB