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Objective To investigate the optimal workflow and protocol for integrated PET/MR by comparison with PET/CT.Methods A total of 228 patients were enrolled in this study for PET/CT and PET/MR evaluation on the same day.Six PET/MR protocols with different MR sequences but the same PET acquisition protocol were investigated and the optimal protocol was identified based on image quality,acquisition time and diagnostic performance.Results PET/MR workflow was similar to PET/CT,however,some special issues needed to be considered for PET/MR.Among the 6 protocols,protocol No.6 outperformed others for body and head regions.Types of artifacts were found more often in PET/MR than in PET/CT.Conclusions By optimizing the protocol,PET/MR could achieve almost the same diagnostic performance as PET/CT.However,the issues of long acquisition time and artifacts on PET/MR need to be further improved.
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<p><b>OBJECTIVE</b>To assess the value of contrast-enhanced ultrasonography (CEUS) and fluorodeoxyglucose positron emission tomography-computed tomography (¹⁸F-FDG PET/CT) in evaluating the stability of carotid atherosclerosis.</p><p><b>METHODS</b>Seventeen patients with 21 carotid artery plaques received examinations with CEUS. According to the nature of the plaques, the patients were divided into soft and mixed plaque group and hard and calcified plaque group. The maximal enhancement intensity of the plaques (I(MAX)) and maximal plaque density (D(MAX)) were measured to quantify the neovasculature. The patients also underwent concurrent ¹⁸F-FDG PET/CT, and ¹⁸F-FDG uptake was quantified by the mean standard uptake values (SUV(mean)), an index reflecting the inflammatory activity in the plaque. The findings in CEUS and PET/CT were comparatively analyzed for these cases.</p><p><b>RESULTS</b>The D(MAX) of the plaque in soft and mixed plaque group was significantly greater than that in hard and calcified plaque group (4.26±3.65 vs 1.41±1.47, P<0.05); the I(MAX) was also greater in the former group, but this difference was not statistically significant (26.83±19.61 vs 24.73±29.85, P=0.869). The soft and mixed plaques tended to have higher SUVmean than the hard and calcified plaques (1.70±0.45 vs 1.47±0.12, P=0.099). The values of I(MAX) and D(MAX) were not found to correlate to SUV(mean) in these patients.</p><p><b>CONCLUSION</b>CEUS can sensitively show the status of neovascularization within the carotid atherosclerosis plaques, and PET/CT reflects the inflammatory activity in the plaques. The combination of these two imaging modalities allows the evaluation of plaque stability in terms of neoangiogenesis and inflammatory activity.</p>
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Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Carotid Stenosis , Diagnostic Imaging , Fluorodeoxyglucose F18 , Positron-Emission Tomography , Tomography, X-Ray ComputedABSTRACT
<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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@#ObjectiveTo discuss the experimental method and the mechanisms on treating diseases by acupuncturing the ST36(Zusanli).MethodsUsing Positron Emission Tomography(PET) and functional Magnetic Resonance Imaging(fMRI) to obtain the experimental data about glycometabolism and cerebral blood stream,using SPM and ROI image-analytical method to obtain the visual experimental evidence when acupuncturing the ST36. ResultsThere are certain increases of glycometabolism and cerebral blood stream in ipsilateral hypothalamus and bilateral temporal lobe, when acupuncturing the ST36. Conclusions Acupuncturing the ST36 can lead to the functional changes in vegetative nerve center and temporal lobe, which is close correlated with the therapeutical effects of ST36.
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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>