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<p><b>BACKGROUND</b>Monocytes and macrophages in atherosclerotic plaque lead to plaque instability. The aim of the study was to determine if plaque neovascularization led to inflammation.</p><p><b>METHODS</b>Patients were consecutively enrolled if their carotid intimal media thickness was > 2 mm, as revealed by duplex ultrasound. The patients then underwent dynamic contrast enhanced magnetic resonance imaging (DCE MRI) and fluorine-18 fluorodeoxyglucose ((18)F-FDG) positron emission tomography combined with computed tomography (PET CT). A target to background ratio (TBR) of ≥ 1.25 or < 1.25 served as the cutoff point for the presence and absence of inflammation, respectively.</p><p><b>RESULTS</b>Twenty-six patients underwent bilateral carotid DCE MRI and 24 patients also underwent PET CT. One hundred and fifty-five plaques were evaluated by both DCE MRI and PET CT. There was no significant difference in plaque morphology between the TBR ≥ 1.25 (n = 61) and TBR < 1.25 (n = 94) groups. No significant differences were found in plasma volume and transfer constant between the TBR ≥ 1.25 and TBR < 1.25 groups.</p><p><b>CONCLUSION</b>Our study did not find a significant correlation between plaque neovascularization and the aggregation of inflammatory cells.</p>
Assuntos
Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças das Artérias Carótidas , Patologia , Agregação Celular , Fluordesoxiglucose F18 , Inflamação , Patologia , Macrófagos , Patologia , Imageamento por Ressonância Magnética , Neovascularização Patológica , Placa Aterosclerótica , Patologia , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios XRESUMO
Objective To investigate the imaging characteristics of both intra- and extrathoracic sarcoidosis on 18F-FDG PET/CT.Methods From 2007 Aug.to 2009 Nov.,22 patients( 10 males,12 females) with sarcoidosis,confirmed by pathological study and clinical follow-up,underwent 18 F-FDG PET/CT imaging.The imaging patterns of intrathoracic and extrathoracic lesions were analyzed.The patterns were classified as the typical or atypical ( symmetrical or asymmetrical FDG accumulation and enlargement of hilar lymph nodes) based on PET and CT separately.Nonparametric McNemar test,independent t-test and Fisher exact test were applied for statistical analysis.Results For typical pattern vs atypical pattem identification,PET was significantly different from CT ( 18 and 4 vs 12 and 10,P =0.031 ).In those with atypical pattern demonstrated by CT alone at hilar region,PET showed either symmetrical or asymmetrical accumulation of FDG.Except for mediastinal lymph nodes involvement,lung parenchyma was the second common site ( 19/22,86.4% ),followed by lymph nodes at abdomen and (or) pelvis ( 12/22,54.5% ).Conclusion The imaging characteristics of both intra- and extrathoracic sarcoidosis on 18F-FDG PET/CT may be helpful for the diagnosis of atypical sarcoidosis on CT image alone.
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Objective To determine the value of 2-18F-2-deoxy-β-D-glucose (18F-FDG)PET/CT in malignancy tumor detection of patients suspected as having paraneoplastic syndrome (PNS).Methods The clinical data of 54 patients suspected as having PNS, underwent PET/CT study in our hospital fiom June 2007 to December 2009, were retrospectively analyzed. The efficacy of 18F-FDG PET/CT on positive detection rate, positive predictive value of malignant tumors and on the detection of malignant tumor markers were analyzed with the results of pathological findings and clinical data;whether the course of disease could affect these detection was also analyzed. Results Positive results of 18F-FDG PET/CT were noted in 17 patients (31.5%), and 13 of them were confirmed as malignant tumors with pathological results. The positive predictive value of 18F-FDG PET/CT was 76.5%. The durations of patients with malignancies were not different from those of patients without malignancies.PET/CT enjoyed a significantly higher efficacy rate in identifying malignant tumors in patients with elevated tumor markers than in patients with tumor markers in normal range (P<0.05). Conclusion 18F-FDG PET/CT improves the tumor detection rate in PNS suspects, especially in patients enjoying elevated tumor markers.
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Objective To assess the feasibility of using PET molecular imaging to evaluate the therapeutic effects of traditional Chinese medicine FuZhiSan (FZS) on the model of aging Alzheimer's disease (AD) rats. Methods Twenty aged AD rats (Sparague-Dawley rats,male) were randomly divided into FZS treated group (n = 10) and control group (n = 10). Another 10 healthy adult rats were as blank controls. Morris water maze record system was used for cognitive function assessment. Before and after FZS treatment 18 F-fluorodeoxyglucose (FDG) and 11 C-2- [4'-(methylamino) phenyl] benzothiazol-6-ol ( PIB )PET imaging was undertaken. After post-treatment imaging procedures the brain tissues of all animals were taken for histochemical study,such as staining with HE,congo red,amyloid β (Aβ) immunofluorescence,5-bromo-2-deoxyuridine (BrdU) immunofluorescence and NeuN immunofluorescence. Paired t-test was performed with SPSS 13.0 software for the data analysis. Results The cognitive dysfunction of aging AD rats was improved after FZS treatment. The escape latency in FZS treated group was significantly shorter than that of control group ((32.5 ±10.8) s vs (102.6±8.8) s,t =15.7987,P=0. 0001). Diffuse neuronal loss and Aβ deposition were detected in the hippocampus and cortex in the aged AD rats. The imaging data showed that brain glucose metabolism was amended in FZS treated group while the abatement of amyloid deposition was not significant. Immunofluorescence results indicated that the neuronal proliferation was more remarkable in FZS treated group. Conclusions It may be feasible to use PET imaging as a method to evaluate the therapeutic effect in AD rats. FZS may ameliorate memory dysfunction of aged AD rats. Its mechanism may be partly contributed to the enhancement of the neuronal proliferation and survival.
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<p><b>OBJECTIVE</b>To assess the value of carbon-11 choline (CH) positron emission tomography (PET) in patients with pulmonary nodules.</p><p><b>METHODS</b>From September 2002 to December 2004, 39 patients with pulmonary nodules were imaged with CH-PET. CH-PET data was analyzed by visual method and semiquantitative method. When pulmonary nodules with abnormal CH uptake appeared in PET scans confirmed by visual method, their maximum and mean standard uptake value (SUVmax and SUVmean) were measured using semiquantitative method. Diagnoses were confirmed by surgery or biopsy and follow-up survey.</p><p><b>RESULTS</b>Twenty-four cancerous and 3 inflammatory nodules and 1 bronchogenic cyst were detected by CH-PET and were diagnosed malignant with visual method. Three bronchial alveolar carcinoma, 2 metastatic tumor from kidney and colon, 3 fibrous nodules, 1 cryptococcosis, 1 hamartoma and 1 sclerosing hemangioma showed nothing abnormal in PET scans. For identification of pulmonary nodules with CH-PET, the sensitivity was 89% (24/29), the specificity was 60% (6/10), and the accuracy was 77% (30/39). There were differences in SUV between 8 squamous cell carcinomas and 9 adenocarcinomas (Z = -2.937, -2.887, P < 0.01). In diagnosing 70 resected enlarged lymph nodes beyond 1 cm in 17 lung cancer patients, CH-PET had the sensitivity of 86% (25/29), the specificity of 90% (37/41), and the accuracy of 89% (62/70). CH-PET confirmed 7 distant metastases in 25 lung cancer patients. In 5 cases suspected brain metastases CH-PET identified 2 cases positive correctly.</p><p><b>CONCLUSIONS</b>CH-PET can confirm malignant pulmonary nodules, but still there were false positive and false negative cases. CH-PET can evaluate N stage effectively in patients with lung cancer. CH-PET can depict brain metastases accurately.</p>
Assuntos
Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radioisótopos de Carbono , Colina , Pulmão , Diagnóstico por Imagem , Patologia , Pneumopatias , Diagnóstico , Neoplasias Pulmonares , Diagnóstico , Tomografia por Emissão de Pósitrons , Métodos , Estudos Retrospectivos , Sensibilidade e EspecificidadeRESUMO
<p><b>OBJECTIVE</b>To assess the features of fluorine-18 fluorodeoxyglucose (FDG) uptake in patients with benign pulmonary nodules.</p><p><b>METHODS</b>From October 1998 to July 2004, 47 patients with benign pulmonary nodules were imaged with FDG-positron emission tomography (PET). Diagnoses were confirmed by surgery. FDG-PET data was analyzed by visual method and semi-quantitive method. When pulmonary nodules with abnormal FDG intake appeared in PET scans confirmed by visual method, their maximum and mean standard uptake value (SUVmax and SUVmean) and SUV of normal lung (SUVlung) were measured using semiquantitative method.</p><p><b>RESULTS</b>Twenty-one cases showed nothing abnormal in PET scans, including 17 calcification and fibrosis, 2 hamartomas and 2 sclerosing hemangiomas. 26 pulmonary nodules were detected by FDG-PET (17 active tuberculous, 6 inflammatory pseudotumors, 3 cryptococcosis). FDG uptake of these 26 nodules was higher than that of normal lung (SUVmax, SUVmean and SUVlung were 3.04 +/- 1.65, 2.48 +/- 1.35 and 0.40 +/- 0.07, respectively, P < 0.001). Correlations were not found between FDG uptake and nodule size or SUV of normal lung or age or blood glucose level in these 26 patients (P > 0.05). SUV in 9 cases (9/26, 35%) were beyond 2.5.</p><p><b>CONCLUSIONS</b>Some benign pulmonary nodules were FDG avid.</p>