ABSTRACT: PurposeThe aim of this study was to compare the diagnostic performance of 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) and voxel-based morphometry (VBM) on magnetic resonance imaging
(MRI) in the same group of patients with very mild Alzheimer’s disease (AD).
MethodsThirty patients with very mild AD (age 67.0±5.8years; MMSE score 25.5±1.2, range 24–28), 32 patients with mild AD (age 67.0±4.5
years, MMSE score 22.1±0.8, range 21–23) and 60 age- and sex-matched normal volunteers underwent both FDG-PET and three-dimensional
spoiled gradient echo MRI. Statistical parametric mapping was used to conduct voxel by voxel analysis and Z score mapping. First, the region of interest (ROI) maps of significant reductions in glucose metabolism and grey matter density
in the mild AD patients were defined. Secondly, analysis of receiver operating characteristic (ROC) curves for Z scores in the ROI maps discriminating very mild AD patients and normal controls was performed.
ResultsIn mild AD patients, FDG-PET indicated significant reductions in glucose metabolism in the bilateral posterior cingulate gyri
and the right parietotemporal area, while VBM analysis showed a significant decrease in grey matter volume density in the
bilateral amygdala/hippocampus complex, compared with the normal control group. ROC analysis showed that in very mild AD patients
the accuracy of FDG-PET diagnosis was 89% and that of VBM-MRI diagnosis was 83%. The accuracy of the combination of FDG-PET
and VBM-MRI diagnosis was 94%.
ConclusionIn very mild AD, both FDG-PET and VBM-MRI had high accuracy for diagnosis, but FDG-PET showed slightly higher accuracy than
VBM-MRI. Combination of the two techniques will yield a higher diagnostic accuracy in very mild AD by making full use of functional
and morphological images.
European journal of nuclear medicine and molecular imaging 06/2006; 33(7):801-809. · 4.99 Impact Factor
ABSTRACT: 2-[Fluorine 18]-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) has played an important role in detecting hypometabolic regions in the brains of patients with dementia. To our knowledge, the optimal imaging time for dementia has not been investigated. The aim of this study was to evaluate the sensitivity of the early scanning (ES) compared with late scanning (LS) for demonstrating decreased regional glucose metabolism in patients with Alzheimer disease (AD).
Twenty patients with mild AD (mean age +/- standard deviation, 64.8 +/- 5.2 years) and 20 age- and sex-matched healthy volunteers (age, 65.9 +/- 4.5 years) were underwent FDG PET. Their cerebral glucose metabolic images were obtained on ES at 30-42 minutes and LS at 60-72 minutes after the administration of FDG 185-346 MBq. We compared regional cerebral metabolic images in a voxel-by-voxel analysis with statistical parametric mapping between patients with AD and control subjects and evaluated the difference in the hypometabolic regions between the two scans.
In the AD-to-healthy comparison, LS at the P < .001 level of significance showed more extensive and significant hypometabolic areas than did ES.
These results indicate that LS is superior to ES in detecting hypometabolic regions in patients with AD. For patients with AD, emission scanning soon after the administration of FDG is probably not advised.
American Journal of Neuroradiology 04/2005; 26(4):843-7. · 2.93 Impact Factor
ABSTRACT: To investigate regional differences in cerebral glucose metabolism and blood flow of dementia with Lewy bodies (DLB), we studied 7 subjects with DLB and 20 normal controls using F-18 fluorodeoxyglucose (FDG) and positron emission tomography (PET) and then examined the same 7 subjects and 20 other normal controls with I-123 iodoamphetamine (IMP) and single photon emission computed tomography (SPECT).
The anatomically standardized images were produced with NEUROSTAT and the regional relative metabolic and perfusional values were calculated.
The mean reduction ratios of FDG uptake in the DLB group relative to the mean normal controls in the parietal lobe and occipital lobe were 0.72 and 0.83, respectively, while the corresponding mean reduction ratios of IMP uptake were 0.81 and 0.88, respectively. In the DLB group, parietal FDG uptake was significantly lower than parietal IMP uptake (p < 0.05), occipital FDG uptake was significantly lower than occipital IMP uptake (p < 0.05), and parietal IMP uptake was significantly lower than occipital IMP uptake (p < 0.01), but there was no difference between parietal and occipital FDG uptake.
Our findings suggest that parietal metabolism and perfusion are severely affected in DLB patients, though the occipital metabolic and perfusional reduction is thought to be a feature of DLB. FDG-PET is thought to be superior to IMP-SPECT in detecting functional changes in the DLB brain.
Annals of Nuclear Medicine 08/2004; 18(5):447-51. · 1.50 Impact Factor
ABSTRACT: To investigate the cerebral glucose metabolism of subjects who had a Clinical Dementia Rating (CDR) of 0.5, we studied 40 subjects whose CDR was 0.5 and 40 age-matched healthy subjects.
Cerebral glucose image of each subject was obtained by [18F]-2-fluoro-deoxy-D-glucose (FDG) positron emission tomography (PET). The anatomically standardized images were produced with NEUROSTAT. Then, the two groups were compared with the Statistical Parametric Mappings (SPM) 99.
A comparison with the SPM 99 revealed that relative cerebral glucose metabolism was lower in the posterior cingulate gyri and parietal lobules in the CDR 0.5 group than in the healthy subjects group.
These findings are very similar to those in patients with probable Alzheimer's disease (AD) and suggest that the majority of subjects with CDR 0.5 are suffering from very mild AD or at least a prodromal state of AD.
Journal of the Neurological Sciences 11/2003; 215(1-2):71-4. · 2.35 Impact Factor
ABSTRACT: The purpose of this study was to delineate the specific patterns of cerebral glucose metabolism with regard to the time of onset of Alzheimer's disease (AD).
Two groups of 20 AD patients with different ages of onset were examined. The early onset (EO) and late onset (LO) groups had mean ages of onset of 53.9 and 72.7 years. Groups of age-matched normal subjects were used as controls. A regional relative cerebral glucose metabolic image of each subject was obtained by 2-[18F] fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET). NEUROSTAT program was used for spatial normalization and voxel-based statistical parametric mapping (SPM) 99 was used for statistical analyses.
Both AD groups had significant hypometabolic regions in the bilateral parieto-temporal regions compared with the age-matched groups. The EO group had more severe hypometabolism in the bilateral parietal and posterior cingulate cortices and precuneus region than the LO group. However, LO group showed no significant hypometabolic regions compared to the EO group.
The effects of time of AD onset were delineated as a double dissociation, that is, EO AD patients have a more severe reduction of glucose metabolism. Our finding suggests the existence of biological subtypes of AD.
Journal of the Neurological Sciences 09/2002; 200(1-2):27-32. · 2.35 Impact Factor
ABSTRACT: Some studies have examined gender differences in brain function based on cerebral blood flow and cerebral metabolism by using positron emission tomography (PET). However, the findings of these studies are controversial and most of them were analyzed by the regions of interest (ROIs) method. Here, we evaluated gender differences of cerebral glucose metabolism under the resting state in a voxel-based analysis.
We studied 44 healthy volunteers (22 females, 63.0+/-6.3 years, and 22 males, 63.1+/-8.4 years). Cerebral glucose metabolic images were obtained with (18)F-fluorodeoxyglucose (FDG) and PET. All individual data were transformed to standard brain space and the male and female groups were compared using statistical parametric mapping (SPM).
The males had significantly higher glucose metabolism in the right insula, middle temporal gyrus, and medial frontal lobe than the females. Glucose metabolism in the hypothalamus was significantly higher in females than in males. There was a significant correlation between aging and glucose metabolism in the left thalamus in males and in the left caudate nucleus and hypothalamus in females. In males, but not females, there was a significant asymmetry between the bilateral hemispheres.
We found that there were obvious gender differences in regional cerebral glucose metabolism and this is the first report of higher glucose metabolism in the hypothalamus in females than in males.
Journal of the Neurological Sciences 08/2002; 199(1-2):79-83. · 2.35 Impact Factor
ABSTRACT: The authors' goal was to determine whether FDG uptakes in various regions of the brain are different for early and late scanning time in positron emission tomography (PET).
F-18 fluorodeoxyglucose (FDG) PET was performed on 15 healthy normal subjects to obtain early and late acquisition glucose metabolic images (30 and 60 min after FDG injection), respectively. The two sets of images were compared in a voxel-by-voxel analysis.
In the bilateral posterior cingulate gyrus, parietal and frontal association cortices, and subcallosal cortices, the FDG uptakes were larger on the late scan image than on the early scan image, and the FDG uptakes were larger in the cerebellar hemisphere, vermis and frontal basis on the early scan image than on the late scan image.
These results suggest that there are different regional FDG uptakes depending on the scanning time after FDG injection and we must be careful in replacing conventional FDG PET scanning with early scanning in FDG PET study.
Annals of Nuclear Medicine 07/2002; 16(4):299-301. · 1.50 Impact Factor
ABSTRACT: Progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD) are neurodegenerative disorders that may be accompanied by dementia and parkinsonism as clinical symptoms. The purpose of this study was to elucidate cerebral metabolic differences of these two diseases with cognitive impairments by [18F] fluorodeoxyglucose (FDG) and positron emission tomography (PET).
A total of 12 patients with PSP (age: 62.8+/-6.0 years old, m: 7, f: 5, Mini-Mental State Examination (MMSE): 23.4+/-2.6), 12 patients with CBD (age: 64.8+/-6.3 years old, m: 6, f: 6, MMSE: 22.9+/-4.5), and age-matched healthy subjects (normal control (NC)) (age: 63.8+/-7.7 years old, m: 7, f: 5) were subjected to FDG-PET to obtain glucose metabolic images. We compared regional cerebral metabolic images by a voxel-by-voxel analysis with statistical parametric mapping (SPM) among PSP, CBD, and NC subjects, and evaluated differences of hypometabolic regions.
The patients with PSP showed reduced cerebral glucose metabolism in the medial and lateral frontal gyri, basal ganglia, and midbrain compared with NC, whereas the patients with CBD showed significant reduction in the parietal lobes (p<0.001). SPM also revealed parietal hypometabolism in CBD patients compared with PSP patients (p<0.001).
The predominant parietal glucose metabolic reduction in CBD patients was different from previously reported findings. This finding would be the characteristic substance of patients with CBD accompanying cognitive impairments. Our findings suggest that measurement of glucose metabolism by PET and a voxel-based analysis is useful to understand the pathophysiology of these two diseases with cognitive impairments.
Journal of the Neurological Sciences 07/2002; 199(1-2):67-71. · 2.35 Impact Factor