Magnetic Resonance and Single-Photon Emission Tomography Findings in a Pair of Twins Discordant for Alzheimer's Disease

1996 ◽  
Vol 6 (2) ◽  
pp. 76-80
Author(s):  
Cristina Geroldi ◽  
Giovanni B. Frisoni ◽  
Alberto Beltramello ◽  
Claudia Weiss ◽  
Angelo Bianchetti ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Magnetic Resonance ◽  
Single Photon ◽  
Photon Emission ◽  
Single Photon Emission Tomography ◽  
Emission Tomography ◽  
Single Photon Emission ◽  
Photon Emission Tomography

Combined Magnetic Resonance Imaging and Single-Photon Emission Tomography Scanning in the Discrimination of Alzheimer's Disease From Age-Matched Controls

2001 ◽  
Vol 13 (2) ◽  
pp. 149-161 ◽  
Author(s):  
John T. O'Brien ◽  
David Ames ◽  
Patricia Desmond ◽  
Meir Lichtenstein ◽  
David Binns ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Alzheimer’S Disease ◽  
Magnetic Resonance ◽  
Single Photon ◽  
Photon Emission ◽  
Single Photon Emission Tomography ◽  
Emission Tomography ◽  
Resonance Imaging ◽  
Single Photon Emission ◽  
Photon Emission Tomography

Objective: To compare the utility of temporal lobe magnetic resonance imaging (MRI) and single-photon emission tomography (SPET) scanning in discriminating between subjects with Alzheimer's disease (AD) and age-matched controls. Methods: Thirty subjects with NINCDS-ADRDA AD (23 probable AD, 5 possible AD, 2 definite AD) and 22 age- and sex-matched controls underwent T1-weighted coronal MRI scanning (0.3 T) and technetium 99m-HMPAOSPET scanning. MRI scans were analyzed using a digitizer system with volumes of hippocampus, amygdala, entorhinal cortex, parahippocampal gyrus, and whole cerebral cortex calculated. From SPET scans, regional cerebral blood flow (rCBF) was assessed in anterior and posterior frontal, parietal, occipital, and mesial temporal cortex using a region of interest analysis with the cerebellum as a reference area. Results: Using MRI, the areas that best separated groups were left hippocampal and left amygdala volume, resulting in correct classification (patient vs. control) in 79% of cases (sensitivity 77%, specificity 82%). Exactly the same proportion of subjects were correctly classified by SPET, with the most discriminating rCBF changes being left parietal and right posterio frontal. Combining information from both scans improved the proportion of correctly classified subjects in a discriminant function to 90% (sensitivity 93%, specificity 86%, only 2AD and 3 controls misclassified). All AD subjects had abnormalities on MRI and/or SPET (sensitivity for combined examinations 100%), while abnormalities on both MRI and SPET had a positive predictive value of 100% for dementia (including the detection of one control subject who later had dementia). Significant correlations between MRI and SPET measures were seen in control subjects but not in patients. Conclusion: Both 0.3 T MRI and single rotating gamma camera SPET were equally useful in separating AD subjects from age-matched controls, although the combination of both significantly enhanced discrimination. In particular, all AD subjects had abnormalities on either MRI or SPET and both techniques may have an important role in assisting with clinical diagnosis, though replication in other centers and examination of differentiation of AD from other causes of dementia need to be examined.

The pattern of function-related regional cerebral blood flow investigated by single photon emission tomography with99mTc-HMPAO in patients with presenile Alzheimer's disease and Korsakoff's psychosis

1989 ◽  
Vol 19 (4) ◽  
pp. 847-855 ◽  
Author(s):  
R. Hunter ◽  
R. McLuskie ◽  
D. Wyper ◽  
J. Patterson ◽  
J. E. Christie ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Blood Flow ◽  
Single Photon ◽  
Photon Emission ◽  
Emission Tomography ◽  
Regional Cerebral Blood ◽  
Single Photon Emission ◽  
Cortical Areas ◽  
Photon Emission Tomography

SYNOPSISSingle photon emission tomography (SPET) with the lipophilic blood flow marker99mTc-hexamethyl propyleneamine oxime (99mTc-HMPAO) has been used to determine regional uptake of radiolabel into brain regions of patients with presenile Alzheimer's disease and Korsakoff's psychosis, and age-matched controls. Using occipital cortical uptake as reference area, the pattern of relative regional cerebral blood flow (rCBF) was determined in other cortical areas and basal ganglia. In Alzheimer's disease, reduction in rCBF occurred most strikingly in posterior temporal and parietal areas. By contrast, in Korsakoff's psychosis, posterior temporal rCBF was maintained, although there was a trend to reduced tracer uptake in other cortical areas. These impairments of flow were correlated with impairments of neuropsychological function. In Alzheimer's disease, left posterior temporal and left parietal regions in particular showed rCBF to be strongly correlated with most aspects of cognitive function. In Korsakoff's psychosis, however, impaired flow in frontal regions was correlated with impaired performance on tests of memory and orientation. The findings in Alzheimer's disease show quantitative parallels with those from studies using Positron Emission Tomography (PET), and extend our understanding of the relationship between cognition and regional brain function in dementia. The findings in Korsakoff's psychosis offer the first direct evidence linking frontal lobe dysfunction with the cognitive impairment seen in the disorder.

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