18F-FDG PET and perfusion SPECT in the diagnosis of Alzheimer and Lewy body dementias (original) (raw)
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Dementia and Geriatric Cognitive Disorders, 2005
Objective: The diagnostic potential of F-18-2-fluoro-2-deoxy-D-glucose positron emission tomography (PET) and technetium-99m hexamethylpropylene amine oxime single-photon emission tomography (SPET) in early detection and differential diagnosis of early dementia was evaluated including a comparison of metabolic and perfusion indices (PI). Methods: Twenty-four patients with initial clinical suspicion of beginning dementia were examined, 12 of them with mild cognitive impairment. All patients underwent SPET and PET within 2 weeks. Data were compared with the final clinical diagnosis at follow-up – 9 with Alzheimer’s disease (AD), 1 with frontotemporal dementia, 1 with vascular dementia (VD), 7 with mixed type of dementia (MIX) and 6 without any type of dementia. Metabolic indices (MI) and PI were compared with each other. The regional cerebral blood flow difference (rCBFdiff) calculated as local uptake difference between the right and left hemisphere was measured for patients with VD a...
SPECT as a diagnostic test in the investigation of dementia
Journal of The Neurological Sciences, 2002
Single photon emission tomography (SPECT) permits the assessment of the decrease of regional cerebral blood flow (rCBF). The aim of this study was to assess the relationship between the different types of dementia (Alzheimer's disease (AD), vascular dementia (VaD) and frontotemporal dementia (FTD)) and the rCBF in the SPECT examination. In patients with AD, the SPECT examination showed hypoperfusion in temporoparietal regions, contrary to patients with frontotemporal dementia, where hypoperfusion was limited to the frontal area, and compared to patients with VaD, where ''patchy'' rCBF changes were observed in different regions. In mild cases of AD, perfusion deficits were observed in the frontal regions equal to those in VaD. The study shows that the SPECT examination may be useful in distinguishing between AD, VaD, and FTD; however, for proper diagnosis in the early stages of AD, additional factors must be taken into consideration. D
Current role of 18F-FDG-PET in the differential diagnosis of the main forms of dementia
Clinical and Translational Imaging, 2020
Purpose We aim to present and critically evaluate the use of FDG-PET in the differential diagnosis between dementing conditions including Alzheimer disease (AD), frontotemporal dementia (FTD) and its variants, vascular dementia (VaD) and pseudodepressive dementia. Methods This review is based on the available consensus recommendations for the use of FDG-PET and current clinical diagnostic criteria. In addition, we updated these reviews with relevant publications in the field after conducting a literature search during the last 5 years through predefined keyword strings relating to the specific terms related to the diseases covered in this review and a common part ('FDG-PET'). Results Neurodegenerative disease are complex groups of several forms of dementia and their clinical diagnostic criteria are progressively incorporating imaging biomarkers as a supporting tool. The role of FDG-PET is currently increasing as part of the clinical practice supporting the clinical diagnosis of AD (at both mild cognitive impairment-MCI-and early dementia stages), FTD and its variants, as well as VaD and pseudodepressive dementia. The pattern of AD is well defined and its negative predicted value may help the differential diagnosis when comorbidities like vascular disease or depression are present. However, the formal evidence supporting the use of FDG-PET is reasonable for MCI due to AD, and the differential diagnosis between FTD and AD, but lacking for the remaining clinical uses. Interestingly, the evidence provided during the last years reinforces these recommendations and gives additional clues about the usefulness of semiquantitative methods in addition to visual reading. Conclusion The large experience accumulated using FDG-PET for the differential diagnosis of the main conditions with dementia has been translated into more formal evidence to support its clinical use. Although FDG-PET form currently part of the clinical practice in many countries, there is still a lack of studies using standardized analysis that confirm specific patterns at individual level.
Clinical utility of FDG-PET for the differential diagnosis among the main forms of dementia
European journal of nuclear medicine and molecular imaging, 2018
To assess the clinical utility of FDG-PET as a diagnostic aid for differentiating Alzheimer's disease (AD; both typical and atypical forms), dementia with Lewy bodies (DLB), frontotemporal lobar degeneration (FTLD), vascular dementia (VaD) and non-degenerative pseudodementia. A comprehensive literature search was conducted using the PICO model to extract evidence from relevant studies. An expert panel then voted on six different diagnostic scenarios using the Delphi method. The level of empirical study evidence for the use of FDG-PET was considered good for the discrimination of DLB and AD; fair for discriminating FTLD from AD; poor for atypical AD; and lacking for discriminating DLB from FTLD, AD from VaD, and for pseudodementia. Delphi voting led to consensus in all scenarios within two iterations. Panellists supported the use of FDG-PET for all PICOs-including those where study evidence was poor or lacking-based on its negative predictive value and on the assistance it provid...
Journal of Nuclear Medicine, 2009
Neuroimaging is increasingly used to supplement the clinical diagnosis of dementia with Lewy bodies (DLB) by showing reduced occipital metabolism and perfusion and reduced striatal dopaminergic innervation. We aimed to optimize the interpretation of 18 F-FDG PET images for differentiating DLB from Alzheimer disease (AD) and to compare the results with dopamine transporter imaging using 123 I-b-carbomethoxy-3ß-(4-iodophenyl)tropane ( 123 I-b-CIT) SPECT. Methods: Fourteen subjects with a clinical diagnosis of DLB and 10 with AD underwent both 18 F-FDG PET and 123 I-b-CIT SPECT. Four DLB and 1 AD diagnoses were subsequently confirmed at autopsy. Diagnostic accuracy was calculated for visual interpretation by 3 readers of standard 3-plane and stereotactic surface projection 18 F-FDG PET images, receiver-operating-characteristic analysis of regional 18 F-FDG uptake, and a cutoff value for the striatal-to-occipital binding ratio of b-CIT defined by receiver-operating-characteristic analysis. Results: Visual interpretation of 3-plane 18 F-FDG PET images had a sensitivity of 83% and specificity of 93% for DLB, slightly higher than the results with the stereotactic surface projection images. Regionally, hypometabolism in the lateral occipital cortex had the highest sensitivity (88%), but relative preservation of the mid or posterior cingulate gyrus (cingulate island sign) had the highest specificity (100%). Region-of-interest analysis revealed that occipital hypometabolism and relative preservation of the posterior cingulate both had a sensitivity of 77% and specificity of 80%. b-CIT achieved 100% accuracy and greater effect size than did 18 F-FDG PET (Cohen d 5 4.1 vs. 1.9). Conclusion: Both 18 F-FDG PET and 123 I-b-CIT SPECT appear useful for the diagnosis of DLB, although the latter provides more robust results. The cingulate island sign may enhance the specificity of 18 F-FDG PET.
18F-FDG PET Improves Diagnosis in Patients with Focal-Onset Dementias
The Journal of Nuclear Medicine, 2015
Alzheimer disease is the cause of up to one-third of cases of primary progressive aphasia or corticobasal syndrome. The primary objective of this study was to determine the accuracy of 18 F-FDG PET metabolic imaging for the detection of Alzheimer disease in patients with primary progressive aphasia or corticobasal syndrome. Methods: A cohort of patients (n 5 94), including those with an expert clinical diagnosis of logopenic (n 5 19), nonfluent (n 5 16), or semantic (n 5 13) variants of primary progressive aphasia, corticobasal syndrome (n 5 14), or Alzheimer disease (n 5 24), underwent 18 F-FDG metabolic and 11 C-labeled Pittsburgh compound B (11 C-PiB) amyloid PET brain imaging. 18 F-FDG PET scans interpreted with Neurostat and 3D-SSP displays were classified as revealing Alzheimer disease or "other" by interpreters who were unaware of the clinical assessments and 11 C-PiB PET results. 11 C-PiB PET imaging was considered to be the diagnostic reference standard, with a threshold standardized uptake value ratio of 1.5 being indicative of Alzheimer disease pathology. To address possible bias from subgroup selection for the Alzheimer disease binary classifier, we calculated both conventional and balanced accuracies. Results: Diagnoses of Alzheimer disease based on 18 F-FDG PET resulted in 84% accuracy (both conventional and balanced). In comparison, diagnoses based on clinical assessments resulted in 65% conventional accuracy and 67% balanced accuracy. Conclusion: Brain 18 F-FDG PET scans interpreted with Neurostat and 3D-SSP displays accurately detected Alzheimer disease in patients with primary progressive aphasia or corticobasal syndrome as focal-onset dementias. In such diagnostically challenging cohorts, 18 F-FDG PET imaging can provide more accurate diagnoses, enabling more appropriate therapy.
FDG-PET improves diagnosis in patients presenting with focal onset dementias �
2015
Alzheimer’s disease is the cause of up to one third of cases of primary progressive aphasia or corticobasal syndrome. The objective of this study was to determine the accuracy of FDG-PET metabolic imaging for detection of Alzheimer’s disease in patients with primary progressive aphasia or corticobasal syndrome. Methods: A cohort of subjects (n = 94) including those with expert clinical diagnosis of logopenic (n = 19), non-fluent (n = 16) or semantic (n = 13) variants of primary progressive aphasia, corticobasal syndrome (n = 14), or Alzheimer’s disease (n = 24) underwent F18-FDG metabolic and C11-PiB amyloid PET brain imaging. FDG-PET scans read with Neurostat 3D-SSP software displays were classified as Alzheimer’s disease or other by readers blind to the clinical assessments and PiB-PET results. PiB-PET imaging was considered the diagnostic reference standard with a threshold standardized uptake value ratio of 1.5 indicative of Alzheimer’s disease pathology. To address biases from ...
The Lancet Neurology, 2007
Background Dementia with Lewy bodies (DLB) needs to be distinguished from other types of dementia because of important diff erences in patient management and outcome. Current clinically based diagnostic criteria for DLB have limited accuracy. Severe nigrostriatal dopaminergic degeneration occurs in DLB, but not in Alzheimer's disease or most other dementia subtypes, off ering a potential system for a biological diagnostic marker. The primary aim of this study was to investigate the sensitivity and specifi city, in the ante-mortem diff erentiation of probable DLB from other causes of dementia, of single photon emission computed tomography (SPECT) brain imaging with the ligand ¹²³I-2βcarbometoxy-3β-(4-iodophenyl)-N-(3-fl uoropropyl) nortropane (¹²³I-FP-CIT), which binds to the dopamine transporter (DAT) reuptake site. Diagnostic accuracy, positive and negative predictive values, and inter-reader agreement were the secondary endpoints and a subgroup of possible DLB patients was also included.
Journal of nuclear medicine : official publication, Society of Nuclear Medicine, 1994
SPECT studies of regional cerebral perfusion with a high-resolution system were compared to PET studies of regional cerebral glucose utilization (rCMRglc) in 21 patients with probable Alzheimer's disease (AD). Ten normal subjects were also evaluated with SPECT and 10 with PET. rCMRglc (for PET) and counts (for SPECT) in the associative cortices were normalized to the average rCMRglc, and counts in the calcarine cortex and basal ganglia were considered as a "reference area" to obtain a ratio. The ratio differences between patients and controls were tested with ANOVA performed separately for PET and SPECT. The difference between probable AD patients and controls was significant for both PET (p < 0.00001) and SPECT (p < 0.005); this difference was significant for the frontal, temporal and parietal cortices (p < 0.0001) for PET, and for the temporal (p < 0.005) and parietal (p < 0.001) cortices for SPECT. Temporo-parietal defects were detected in all subject...
Journal of nuclear medicine : official publication, Society of Nuclear Medicine, 1997
Dementia of the Alzheimer's type [(S)DAT] and dementia with frontal features (FLD) are nosological entities with different prognoses and presumed pathophysiology. There is a need for noninvasive differential diagnostic tools. To evaluate whether SPECT perfusion imaging could discriminate between these neurodegenerative disorders, we performed a comparative study. SPECT scans using 99mTc-hexamethylpropylene amine oxime (99mTc-HMPAO) of 21 patients with FLD were compared with those obtained in a group of 19 age- and severity-matched patients suffering from (S)DAT. Brain SPECT perfusion deficits were scored by visual qualitative analysis with respect to location, lateralization and severity. A total severity score of cerebral hypoperfusion (maximal value = 18) was calculated by adding all severity scores (scored between 0 and 3; 0 = no perfusion deficit; 1 = 13%-30% hypoperfusion; 2 = 30%-50%, hypoperfusion and 3 = > 50% hypoperfusion including breaching of the cortex) for right...