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Objective:To investigate the value of multiple parameters and the combined model based on 18F-fluorodeoxyglucose (FDG) PET/MR in the differential diagnosis of benign and malignant pancreatic tumors. Methods:A total of 76 patients (50 males, 26 females, age (45.2±18.0) years) with clinically suspected pancreatic tumor who underwent PET/MR between December 2012 and September 2020 in First Medical Center of Chinese PLA General Hospital were retrospectively selected. All patients had definitive diagnoses. PET/MR sequences included T 1 weighted imaging (WI; convention and contrast enhancement), T 2WI, diffusion weighted imaging (DWI) and 18F-FDG PET sequences. Morphological characteristics and scores of lesions in MRI were evaluated. Parameters including parameters of PET and DWI, as well as parameters derived from histogram analysis of apparent diffusion coefficient (ADC) and standardized uptake value (SUV) (maximum (max), minimum (min), mean, median, standard deviation (SD), skewness, kurtosis, entropy) were measured. Independent-sample t test or Mann-Whitney U test were used for data analysis. PET/MR combined model was measured based on logistic regression analysis. Receiver operating characteristic (ROC) curve analysis was used to calculate the differential diagnosis efficacy of PET/MR multiparameters and combined model for benign and malignant lesions. Results:Among 76 patients, 55 were malignant and 21 were benign. (1) Visual evaluation. The main manifestations of pancreatic cancer were unclear margin, abnormal internal MR signal and enhancement, decreased ADC signal and increased radioactive uptake. The main manifestations of benign tumor lesions of pancreas were clear margin, even signal and enhancement, no reduction of ADC, decreased radioactive uptake. (2) Diagnostic efficacy. Multiparameter model established based on logistic regression analysis included SUV max, SUV SD, ADC entropy and ADC skewness. The efficiency of differential diagnosis for benign and malignant pancreatic tumors were shown as follows: multiparametric diagnostic model>ADC entropy>MR score>SUV max>SUV SD>ADC skewness. The multiparametric diagnostic model had the best diagnosis efficiency with the area under curve (AUC) of 0.86, the sensitivity of 69.1%(38/55), and the specificity of 100%(21/21) ( z=-8.73, P<0.001). Conclusions:MR score and multiple quantitative parameters obtained from 18F-FDG PET/MR can be used to differentiate benign and malignant pancreatic tumors. Compared with independent parameter of PET/MR, multiparametric model can further improve the diagnostic efficiency.
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Objective:To compare the accuracy of visual qualitative assessment and semi-quantitative analysis for 18F-florbetaben ( 18F-FBB) β-amyloid (Aβ) imaging in the diagnosis of Alzheimer′s disease (AD) and to explore their clinical application value. Methods:From January 2019 to October 2019, 17 patients (8 males, 9 females, age (74.1±8.5) years) with mild/moderate-stage clinically probable AD and 17 cognitive normal control (NC; 9 males, 8 females, age (64.5±6.3) years) were prospectively enrolled in this study. All patients underwent dynamic 18F-FBB PET/CT brain imaging in the Chinese PLA General Hospital. Visual qualitative assessment and semi-quantitative analysis methods were used to analyze PET brain imaging results. The difference of standardized uptake value ratio (SUVR) between the two methods was analyzed by using independent sample t test. The consistency of the two methods and clinical results was analyzed by Kappa test. The cut-off value of SUVR for the diagnosis of AD was determined by receiver operating characteristic (ROC) curve. Results:The sensitivity, specificity and accuracy of visual qualitative assessment to diagnose AD were 14/17, 16/17 and 88.2% (30/34). The global SUVR of NC and AD group were 1.09±0.85 and 1.75±0.25 ( t=-10.263, P<0.001), and the composite SUVR were 1.16±0.57 and 1.89±0.15 ( t=-10.789, P<0.001), respectively. The cut-off value of SUVR for the diagnosis of AD was 1.47, with the sensitivity of 15/17, the specificity of 16/17 and the accuracy of 91.2%(31/34). The visual qualitative assessment and semi-quantitative analysis had good consistency with clinical diagnosis results with Kappa value of 0.765 and 0.824 respectively (both P<0.001). Conclusion:The visual qualitative assessment and semi-quantitative analysis methods used in 18F-FBB Aβ imaging to diagnose AD patients show high accuracy and can provide effective value for clinical diagnosis, but the visual qualitative assessment method is concise and easy to grasp, which is worth further promotion and use in clinical.
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@#Objective To investigate the effect of electroacupuncture on glucose metabolism of the cerebral motor function regions in normal subjects and stroke patients.Methods The glucose metabolism of cerebral motor area in normal subjects and stroke patients before and after acupuncture at Baihui(GV20)and left Qubin(GB7)during the movement were observed with positron emission tomography(PET).Results Acupuncture could increase metabolism of glucose in bilateral superior parietal lobule(LPs)and precuneus,especially in the left among the healthy subjects.For the stroke patients The similar changes of metabolic were observed in the first somastic motor cortical region(MI),premotor cortex(PMC),LPs bilaterally,as well as the supplementary motor area(SMA)of healthy side after acupuncture.Conclusion Acupuncture at Baihui(GV20)and Qubin(GB7)can regulate the glucose metabolism in cerebral structures related to motor function in the bilateral cerebral hemispheres,which may systematically induce excitement of motor nerve,expiate or assist the injured nerve network and expedite the reestablishment of the cerebral motor function.
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<p><b>BACKGROUND</b>To evaluate the diagnostic significance of FDG PET in preoperative mediastinal lymph node staging for NSCLC.</p><p><b>METHODS</b>Whole-body FDG PET imaging was performed in 70 patients with NSCLC. All patients received thoracic CT examination 2 weeks before PET scan or 1 week after PET scan, and then were given thoracotomy with hilar and mediastinal lymph nodes dissection. After intravenous administration of 18F-FDG (150μCi/kg), PET scan was performed in 3-7 bed positions with 2D acquisition and OSEM reconstruction. For quantitative evaluation, a region of interest (ROI) was placed over the mediastinal lymph node which had abnormal uptake of radiation activity, then the standardized uptake value (SUV) were calculated. If SUV≥2.5 or uptake activity was higher than the blood pool of mediastinal on the basis of visual inspection, it was considered to be positive.</p><p><b>RESULTS</b>The sensitivity, specificity and accuracy of PET were 100%, 93% and 94%, respectively. The positive lymph nodes diagnosed by PET correctly corresponded to pathological results. PET changed the clinical staging of 12 patients. The sensitivity, specificity and accuracy of CT were 70%, 77% and 76%, respectively.</p><p><b>CONCLUSIONS</b>PET is an effective modality for accurate mediastinal lymph node staging in patients with NSCLC. It is valuable for determining clinical treatment.</p>
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<p><b>OBJECTIVE</b>To explore the experimental method of obtaining position emission tonogiaphy (PET) imaging evidence of changes in cerebral function by puncturing the Stomach 36 (ST36, Zusanli) acupoint.</p><p><b>METHODS</b>Data on changes of cerebral glycometabolism were obtained from six healthy male volunteers with positron emission tomography. Visual experimental evidence, as well as statistical parametric mapping (SPM), was gathered while puncturing the ST36 (Zusanli, right leg) acupoint.</p><p><b>RESULTS</b>There was increased glycometabolism in the hypothalamus, head of the caudate nucleus, temporal lobe, the sinistral cerebellum, postcentral gyrus, and brain stem while the acupoint ST36 was being punctured.</p><p><b>CONCLUSIONS</b>Acupuncture on ST36 can lead to increase in glycometabolism in the vegetative nerve centers, which is correlated with gastric function. Visual experimental evidence of ST36 acupuncturing on functional gastrointestinal disorder was obtained in our study.</p>
Subject(s)
Adult , Humans , Male , Acupuncture , Acupuncture Points , Brain , Diagnostic Imaging , Physiology , Glucose , Metabolism , Tomography, Emission-ComputedABSTRACT
@#ObjectiveTo discuss the central modulating mechanisms while acupuncturing the Stomach 36[ST36(Zusanli)]by brain functional imaging with positron emission tomography (PET).MethodsPET imaging of whole brain was performed in a group of six healthy subjects during two stimulation paradigms: pseudo acupuncture and real acupuncture at acupoint ST36(Zusanli). The data on cerebral glycometabolism,obtained by using PET,was analyzed by using statistical parametric mapping (SPM).ResultsThere was certain increase of glycometabolism in ipsilateral hypothalamus,back of medulla oblongata;bilateral insular lobe; contralateral paracentral lobule,superior part of precentral and postcentral gyrus,opercular part of frontal and temporal lobe,middle part of cingulate gyrus,head of caudate nucleus,middle part of the back of midbrain and pons,and deep part of cerebellum,whereas decrease in ipsilateral superior part of precentral and postcentral gyrus and lateral part of ipsilateral anterior cerebellar lobe,while acupuncturing at acupoint ST36(Zusanli on the right leg).ConclusionsThe central modulating mechanisms of acupuncturing ST36 are realized by neural and neuroendocrine network modulation mechanisms of vegetative nerve center in cortex and subcortex.
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<p><b>OBJECTIVE</b>To assess the relationship between histological type and fluorine-18 fluorodeoxyglucose(FDG) uptake in patients with primary lung cancer and the factors affecting FDG uptake.</p><p><b>METHODS</b>From October 1998 to April 2001, 82 patients with lung cancer were imaged with FDG-PET (Positron emission tomography) before surgery or biopsy. Their maximum and mean standard uptake value(SUVmax and SUVmean) of tumor and SUV of normal lung (SUVlung) were measured.</p><p><b>RESULTS</b>All tumors were detected by FDG-PET(r)FDG uptake of tumor was higher than that of normal lung (P < 0.01). FDG uptake was lower in adenocarcinoma(AC) than in squamous cell carcinoma (SQC), and that of bronchial aveolar carcinomas(BAC) was the lowest [SUVmax was 8.42 +/- 4.05,5.91 +/- 3.91 and 2.97 +/- 1.10, respectively; SUVmean was 6.12 +/- 2.90,4.35+/- 3.10 and 2.25 +/- 0.99, respectively (P < 0.01)]. Correlations were found between FDG uptake and tumor size (P < 0.01)(r)Glucose level and SUV of normal lung could affect SUV of lung cancer (P < 0.05).</p><p><b>CONCLUSIONS</b>SUV is higher in cancer tissue than in normal lung tissue. FDG uptake is different among SQC,AC and BAC. FDG uptake and tumor size appear to be correlated with each other.SQC, AC and BAC have their own features respectively. The effects of glucose and SUV lung should be considered in the diagnosis of lung cancer with PET.</p>