Inflammatory myofibroblastic tumor(IMT) in the liver is an uncommon lesion of uncertain pathogenesis.In most cases,symptomatological imaging and clinical studies suggest malignancy.We report a case of liver IMT with i...Inflammatory myofibroblastic tumor(IMT) in the liver is an uncommon lesion of uncertain pathogenesis.In most cases,symptomatological imaging and clinical studies suggest malignancy.We report a case of liver IMT with imaging findings from positron emission tomography/computed tomography(PET/CT),contrastenhanced computed tomography(CECT) and contrastenhanced ultrasonography(CEUS).This report was the first to depict a PET/CT scan of a liver IMT that revealed an inhomogeneous,intense(fluorine 18)-fluoro-2-deoxy-D-glucose uptake.The CECT and CEUS images showed a hepatic artery supplying blood to the mass and necrosis.The characteristic histopathological features and the presence of spindle cells expressing smooth muscle actin,collagen fibers and lymphocytes allowed for the diagnosis of liver IMT.Recognizing such findings will help to achieve a correct diagnosis and may prevent inappropriate treatment.展开更多
In cone-beam computed tomography (CBCT), there are often cases where the size of the specimen is larger than the field of view (FOV) (referred to as over FOV-sized (OFS)). To acquire the complete projection da...In cone-beam computed tomography (CBCT), there are often cases where the size of the specimen is larger than the field of view (FOV) (referred to as over FOV-sized (OFS)). To acquire the complete projection data for OFS objects, some scan modes have been developed for long objects and short but over-wide objects. However, these modes still cannot meet the requirements for both longitudinally long and transversely wide objects. In this paper, we propose a multiple helical scan mode and a corresponding reconstruction algorithm for both longitudinally long and transversely wide objects. The simulation results show that our model can deal with the problem and that the results are acceptable, while the OFS object is twice as long compared with the FOV in the same latitude.展开更多
Coronary artery disease remains a major cause of mortality. Presence of atherosclerotic plaques in the coronary artery is responsible for lu-men stenosis which is often used as an indicator for determining the severit...Coronary artery disease remains a major cause of mortality. Presence of atherosclerotic plaques in the coronary artery is responsible for lu-men stenosis which is often used as an indicator for determining the severity of coronary artery disease. However, the degree of coronary lumen stenosis is not often related to compromising myocardial blood flow, as most of the cardiac events that are caused by atherosclerotic plaques are the result of vulnerable plaques which are prone to rupture. Thus, identification of vulnerable plaques in coronary arteries has become increas-ingly important to assist identify patients with high cardiovascular risks. Molecular imaging with use of positron emission tomography (PET) and single photon emission computed tomography (SPECT) has fulfilled this goal by providing functional information about plaque activity which enables accurate assessment of plaque stability. This review article provides an overview of diagnostic applications of molecular imaging tech-niques in the detection of plaques in coronary arteries with PET and SPECT. New radiopharmaceuticals used in the molecular imaging of coro-nary plaques and diagnostic applications of integrated PET/CT and PET/MRI in coronary plaques are also discussed.展开更多
A novel method for modeling cellular materials is proposed based on MATLAB image processing and synchrotron X-ray computed tomography scan- ning to obtain an accurate calculation result of aluminum foam based on finit...A novel method for modeling cellular materials is proposed based on MATLAB image processing and synchrotron X-ray computed tomography scan- ning to obtain an accurate calculation result of aluminum foam based on finite element model. The maximum entropy algorithm is employed to obtain the bina- rization image, and the median filtering algorithm is used to reduce the noise after binarization. The external contour and internal pores boundary is extracted by the "edge" function in MATLAB, and the geometrical model is reconstructed. A two-step mesh algorithm is adopted to mesh the reconstructed geometrical model. Accordingly, the finite element model of aluminum foam is established by the proposed method based on reconstruction geometrical model. The compression behavior of aluminum foam is obtained at 25℃, 100℃, 200℃ by ABAQUS, and good agreements with experiments are achieved by applying the present recon- struction algorithm and modeling method.展开更多
OBJECTIVE: To investigate antihypertensive effect in rats in order to confirm that twirling reinforcing-reducing manipulation(TRRM) might be the central mechanism underlying the action.METHODS: In the study,^(18) F-2-...OBJECTIVE: To investigate antihypertensive effect in rats in order to confirm that twirling reinforcing-reducing manipulation(TRRM) might be the central mechanism underlying the action.METHODS: In the study,^(18) F-2-fluoro-deoxy-D-glucose positron emission tomography(18 F-FDG-PET)was employed. Fifity-six spontaneous hypertensive rats(SHRs) were randomly divided into a model group, a single-needle acupuncture(SNA) group, a twirling reinforcing group(SNA + TRF) and a twirling reducing(SNA + TRD) group. Fourteen Wistar rats were assigned to the control group. The acupuncture intervention at Taichong(LR 3) acupoint was administered once daily in the SNA, SNA + TRF and SNA + TRD groups for 14 days, with 1 d interval between the two weeks. The blood pressure(BP) of all rats was measured repeatedly and18 F-FDG-PET scans were conducted on the 14 th day. PET images were processed with Statistical Parametric Mapping 8.0.RESULTS: After the intervention, systolic BP showed a significant decrease in the SNA, SNA+TRF and SNA + TRD versus the model groups(all P <0.01) and in the SNA + TRF and SNA + TRD versus the SNA groups(both P < 0.01), with the SNA+TRD group exhibited the best antihypertensive effect(P < 0.01). The key brain regions activated by TRRM were mainly concentrated in the cerebellum, hippocampus, hypothalamus, medulla oblongata, insular cortex, midbrain, thalamus and visual cortex.CONCLUTION: TRRM could significantly lower the BP of SHRs by improving the cerebral glucose metabolism of the activated key brain regions and the underlying central mechanism may be related to the central rennin-angiotensin system and neurotransmission.展开更多
文摘Inflammatory myofibroblastic tumor(IMT) in the liver is an uncommon lesion of uncertain pathogenesis.In most cases,symptomatological imaging and clinical studies suggest malignancy.We report a case of liver IMT with imaging findings from positron emission tomography/computed tomography(PET/CT),contrastenhanced computed tomography(CECT) and contrastenhanced ultrasonography(CEUS).This report was the first to depict a PET/CT scan of a liver IMT that revealed an inhomogeneous,intense(fluorine 18)-fluoro-2-deoxy-D-glucose uptake.The CECT and CEUS images showed a hepatic artery supplying blood to the mass and necrosis.The characteristic histopathological features and the presence of spindle cells expressing smooth muscle actin,collagen fibers and lymphocytes allowed for the diagnosis of liver IMT.Recognizing such findings will help to achieve a correct diagnosis and may prevent inappropriate treatment.
基金Project supported by the National Basic Research Program of China (Grant No. 2011CB707701)the National High Technology Research and Development Program of China (Grant No. 2009AA012200)the National Nature Science Foundation of China(Grant No. 30970722)
文摘In cone-beam computed tomography (CBCT), there are often cases where the size of the specimen is larger than the field of view (FOV) (referred to as over FOV-sized (OFS)). To acquire the complete projection data for OFS objects, some scan modes have been developed for long objects and short but over-wide objects. However, these modes still cannot meet the requirements for both longitudinally long and transversely wide objects. In this paper, we propose a multiple helical scan mode and a corresponding reconstruction algorithm for both longitudinally long and transversely wide objects. The simulation results show that our model can deal with the problem and that the results are acceptable, while the OFS object is twice as long compared with the FOV in the same latitude.
文摘Coronary artery disease remains a major cause of mortality. Presence of atherosclerotic plaques in the coronary artery is responsible for lu-men stenosis which is often used as an indicator for determining the severity of coronary artery disease. However, the degree of coronary lumen stenosis is not often related to compromising myocardial blood flow, as most of the cardiac events that are caused by atherosclerotic plaques are the result of vulnerable plaques which are prone to rupture. Thus, identification of vulnerable plaques in coronary arteries has become increas-ingly important to assist identify patients with high cardiovascular risks. Molecular imaging with use of positron emission tomography (PET) and single photon emission computed tomography (SPECT) has fulfilled this goal by providing functional information about plaque activity which enables accurate assessment of plaque stability. This review article provides an overview of diagnostic applications of molecular imaging tech-niques in the detection of plaques in coronary arteries with PET and SPECT. New radiopharmaceuticals used in the molecular imaging of coro-nary plaques and diagnostic applications of integrated PET/CT and PET/MRI in coronary plaques are also discussed.
基金supported by the National Natural Science Foundations of China(11202007,11232001,and 91216301)
文摘A novel method for modeling cellular materials is proposed based on MATLAB image processing and synchrotron X-ray computed tomography scan- ning to obtain an accurate calculation result of aluminum foam based on finite element model. The maximum entropy algorithm is employed to obtain the bina- rization image, and the median filtering algorithm is used to reduce the noise after binarization. The external contour and internal pores boundary is extracted by the "edge" function in MATLAB, and the geometrical model is reconstructed. A two-step mesh algorithm is adopted to mesh the reconstructed geometrical model. Accordingly, the finite element model of aluminum foam is established by the proposed method based on reconstruction geometrical model. The compression behavior of aluminum foam is obtained at 25℃, 100℃, 200℃ by ABAQUS, and good agreements with experiments are achieved by applying the present recon- struction algorithm and modeling method.
基金Supported by the National Natural Science Foundation of China(Use PET Brain Imaging Technology to Study the Acupuncture Manipulation of Twirling Reinforcing-Reducing Regulation in Spontaneously Hypertensive Rats by Central Integration Signaling Network Construction,No.8157150840)
文摘OBJECTIVE: To investigate antihypertensive effect in rats in order to confirm that twirling reinforcing-reducing manipulation(TRRM) might be the central mechanism underlying the action.METHODS: In the study,^(18) F-2-fluoro-deoxy-D-glucose positron emission tomography(18 F-FDG-PET)was employed. Fifity-six spontaneous hypertensive rats(SHRs) were randomly divided into a model group, a single-needle acupuncture(SNA) group, a twirling reinforcing group(SNA + TRF) and a twirling reducing(SNA + TRD) group. Fourteen Wistar rats were assigned to the control group. The acupuncture intervention at Taichong(LR 3) acupoint was administered once daily in the SNA, SNA + TRF and SNA + TRD groups for 14 days, with 1 d interval between the two weeks. The blood pressure(BP) of all rats was measured repeatedly and18 F-FDG-PET scans were conducted on the 14 th day. PET images were processed with Statistical Parametric Mapping 8.0.RESULTS: After the intervention, systolic BP showed a significant decrease in the SNA, SNA+TRF and SNA + TRD versus the model groups(all P <0.01) and in the SNA + TRF and SNA + TRD versus the SNA groups(both P < 0.01), with the SNA+TRD group exhibited the best antihypertensive effect(P < 0.01). The key brain regions activated by TRRM were mainly concentrated in the cerebellum, hippocampus, hypothalamus, medulla oblongata, insular cortex, midbrain, thalamus and visual cortex.CONCLUTION: TRRM could significantly lower the BP of SHRs by improving the cerebral glucose metabolism of the activated key brain regions and the underlying central mechanism may be related to the central rennin-angiotensin system and neurotransmission.