14 research outputs found
I-123-FP-CIT SPECT in dementia with Lewy bodies, Parkinson's disease and Alzheimer's disease: a new quantitative analysis of autopsy confirmed cases
Purpose The aim of this study was to re-evaluate the differentiation of patients with dementia with Lewy bodies (DLB) from Alzheimer's disease (AD) and Parkinson's disease (PD) using a quantitative analysis of I-123-FP-CIT SPECT scans.Methods Thirty-six patients with in vivo I-123-FP-CIT SPECT and neuropathological diagnoses were included. Based on neuropathological criteria, patients were further subclassified into nine AD, eight DLB, ten PD and nine with other diagnoses. An additional 16 healthy controls (HC) scanned with I-123-FP-CIT SPECT were also included. All images were visually assessed as normal versus abnormal uptake by consensus of five nuclear medicine physicians. Bihemispheric mean was calculated for caudate binding potential (CBP), putamen binding potential (PBP) and putamen-to-caudate ratio (PCR).Results Patients with DLB had significantly lower CBP and PBP than patients with AD and significantly higher PCR than patients with PD. Qualitative visual analysis of the images gave an accuracy of 88% in the evaluation of the status of the nigrostriatal pathway considering all individuals, and 96% considering only the patients with PD, AD and DLB. Quantitative analyses provided a balanced accuracy of 94%, 94% and 100% in binary classifications DLB versus AD, DLB versus PD and PD versus AD, respectively, and an accuracy of 93% in the differentiation among patients with DLB, AD and PD simultaneously. No statistically significant differences were observed between the AD and HC.Conclusions This study demonstrates a very high diagnostic accuracy of the quantitative analysis of(I-123-FP-CIT SPECT data to differentiate among patients with DLB, PD and AD.Neuro Imaging Researc
Are lesion features reproducible between F-18-FDG PET/CT images when acquired on analog or digital PET/CT scanners?
Objectives To compare lesion features extracted from F-18-FDG PET/CT images acquired on analog and digital scanners, on consecutive imaging data from the same subjects. Methods Whole-body F-18-FDG PET/CT images from 55 oncological patients were acquired twice after a single F-18-FDG injection, with a digital and an analog PET/CT scanner, alternately. Twenty-nine subjects were examined first on the digital, and 26 first on the analog equipment. Image reconstruction was performed using manufacturer standard clinical protocols and protocols that fulfilled EARL1 specifications. Twenty-five features based on lesion standardized uptake value (SUV) and geometry were assessed. To compare these features, intraclass correlation coefficient (ICC), relative difference (RD), absolute value of RD (|RD|), and repeatability coefficient (RC) were used. Results In total, 323 F-18-FDG avid lesions were identified. High agreement (ICC > 0.75) was obtained for most of the lesion features pulled out from both scanners' imaging data, especially when reconstruction protocols fulfilled EARL1 specifications. For EARL1 reconstruction images, the features frequently used in clinics, SUVmax, SUVpeak, SUVmean, metabolic tumor volume, and total lesion glycolysis, reached an ICC of 0.92, 0.95, 0.87, 0.98, and 0.98, and a median RD (digital-analog) of 3%, 5%, 4%, - 3% and 1%, respectively. Using standard reconstruction protocols, the ICC were 0.84, 0.93, 0.80, 0.98, and 0.98, and the RD were 20%, 11%, 13%, - 7%, and 7%, respectively. Conclusion Under controlled acquisition and reconstruction parameters, most of the features studied can be used for research and clinical work. This is especially important for multicenter studies and patient follow-ups.Oncologic Imagin
Levantamento da flora apícola em Santa Luzia do Paruá, Sudoeste da Amazônia, Maranhão Survey of bee flora in Santa Luzia do Paruá, Southwest Amazonia, Maranhão
Foi realizado o levantamento das plantas visitadas por Apis mellifera L. através de análise polínica no município de Santa Luzia do Paruá, Maranhão, localizado a noroeste do Estado, em região amazônica. A temperatura média anual varia entre 26 °C e 27 °C, com umidade relativa do ar anual entre 79 a 82% e precipitação pluviométrica entre 2000 a 2400 mm anuais. O estudo foi conduzido entre agosto de 2005 e julho de 2006 em três apiários da região, com coletas mensais de mel, pólen e plantas, que foram submetidas ao método de acetólise. Os tipos polínicos das amostras de mel foram identificados e contados para a determinação da freqüência relativa média. Nas amostras de pólen foi realizada apenas a identificação dos tipos polínicos por meio da comparação com os polens das plantas (botões florais) depositados em coleção de referência. As principais famílias utilizadas por A. mellifera foram Amaranthaceae, Arecaceae, Asteraceae, Urticaceae, Euphorbiaceae, Lamiaceae, Fabaceae-Mimosoideae, Flacourtiaceae, Myrtaceae, Poaceae e Rubiaceae. Em amostras de mel, no período chuvoso destacaram-se os tipos polínicos de Mimosa pudica, Borreria e um tipo indeterminado da família Arecaceae. No período de safra foram representativos Hyptis e um tipo indeterminado de Asteraceae. Os tipos polínicos mais constantes nas amostras de pólen foram Euterpe oleracea, Asteraceae tipo 1, Mimosa pudica e Borreria.<br>The plant species visited by Apis mellifera L. were surveyed by pollen analysis in Santa Luzia do Paruá municipality, located in northwestern Maranhão state. Natural vegetation is Amazon rainforest, mean annual temperature varies between 26°C and 27°C, relative air humidity between 79 and 82%, and total rainfall between 2000 and 2400 mm. This study was conducted from August 2005 to July 2006 in three apiaries of the region, with monthly sampling of honey, pollen and plants. The samples were analyzed by the acetolysis method. The pollen types were identified and counted in honey samples to determine mean frequency of the three apiaries. In the pollen samples, pollen types were identified by comparison with the pollen of plants (flower buds) deposited in the reference collection. The main plant families used as floral resource by A. mellifera are Amaranthaceae, Arecaceae, Asteraceae, Urticaceae, Euphorbiaceae, Lamiaceae, Fabaceae-Mimosoideae, Flacourtiaceae, Myrtaceae, Poaceae and Rubiaceae. In the honey samples, the pollen types of Mimosa pudica, Borreria and members of the Arecaceae family were most important during the rainy season. At harvest time (transition between rainy and dry season), Hyptis, Borreria, and an undetermined pollen type of the Asteraceae family were most important. The pollen types that show major constancy in the sample pollen were Euterpe oleracea, Asteraceae type 1, Mimosa pudica and Borreria