Purpose: Multi-tracer neuroimaging is widely used for the diagnosis, radiotherapy, and neuro-surgery of brain gliomas. Anatomical and functional information is important to avoid having neurological deficits induced d...Purpose: Multi-tracer neuroimaging is widely used for the diagnosis, radiotherapy, and neuro-surgery of brain gliomas. Anatomical and functional information is important to avoid having neurological deficits induced during the resection or radiation therapy of brain gliomas. The aim of this study was to investigate presurgical anatomical labeling of brain gliomas on FLT and FET using statistical probabilistic anatomic maps (SPAM), which are images of cerebral cortical, cerebellar, and subcortical volumes of interest (VOIs). Methods: FDG, FLT, and FET PET scans were acquired. FLT and FET PET images were coregistered to the FDG PET images, which were then spatially normalized onto the target brain. An inverse spatial normalization parameter was calculated and applied to SPAM. For the anatomical labeling of brain glioma regions, the volumes of brain gliomason FLT and FET images were extracted using segmentation. Probabilistic information of the glioma region was then calculated using SPAM and the segmented glioma volumes. SPM and an in-house program were used for image processing. Results: The probability of SPAM labeling a brain glioma region could be extracted using the inverse normalized SPAM and segmented glioma regions. In a sample case, the probabilistic anatomical region of the glioma included 21% of the postcentral gyrus, 12% of the superior parietal gyrus, and 6% of the angular gyrus. Conclusion: Anatomical information about brain gliomas could be extracted using SPAM. This proposed method would be optional for presurgical mapping, to avoid an additional functional mapping study that might otherwise be necessary to avoid producing neurological deficits.展开更多
Objective: Although Iodine-125 (125I) has been widely used for in vitro studies because of its relatively long half-life (60.1 days), 125I imaging is limited because of its low energy (27 - 35 keV), even in an animal-...Objective: Although Iodine-125 (125I) has been widely used for in vitro studies because of its relatively long half-life (60.1 days), 125I imaging is limited because of its low energy (27 - 35 keV), even in an animal-dedicated system. In this study, imaging characteristics of 125I were assessed using a small animal-dedicated imaging system and clinical scanner. Methods: Using the Siemens Inveon and Siemens Symbia TruePoint systems, imaging characteristics such as resolution, sensitivity, and image quality were compared. Mouse high resolution (MHR-0.5), mouse general purpose (MGP-1.0), and mouse high sensitivity (MHS-2.0) collimators were used for the Inveon scanner, and low energy high-resolution (LEHR) and low energy all-purpose (LEAP) collimators were used for the Symbia TruePoint. For animal imaging, 16.8 MBq of 125I was administered to BALB/c mice intravenously, and the planar image and single-photon emission computed tomography (SPECT) were obtained using both scanners. Results: The resolution of 125I for the Inveon scanner was 3.98 mm full width at half maximum (FWHM) at a 30-mm distance with the MHR-0.5 collimator, and the value of Symbia scanner was 8.72 mm FWHM at a 30-mm distance with the LEHR collimator. The sensitivity of 125I for the Inveon scanner was 21.87 cps/MBq, and the value for the clinical scanner was 30.55 cps/MBq. The planar images of mice were successfully obtained at the level of evaluating specific binding in both scanners. Conclusion: 125I small animal imaging can be achieved with a clinical scanner. This result may enhance the utilization of 125I small animal imaging using a clinical scanner.展开更多
Hepatocellular carcinoma(HCC) is one of the most common cancers in Eastern Asia, and its incidence is increasing globally. Numerous experimental models have been developed to better our understanding of the pathogenic...Hepatocellular carcinoma(HCC) is one of the most common cancers in Eastern Asia, and its incidence is increasing globally. Numerous experimental models have been developed to better our understanding of the pathogenic mechanism of HCC and to evaluate novel therapeutic approaches. Molecular imaging is a convenient and up-to-date biomedical tool that enables the visualization, characterization and quantification of biologic processes in a living subject. Molecular imaging based on reporter gene expression, in particular, can elucidate tumor-specific events or processes by acquiring images of a reporter gene's expression driven by tumor-specific enhancers/promoters. In this review, we discuss the advantages and disadvantages of various experimental HCC mouse models and we present in vivo images of tumorspecific reporter gene expression driven by an alphafetoprotein(AFP) enhancer/promoter system in a mouse model of HCC. The current mouse models of HCC development are established by xenograft, carcinogen induction and genetic engineering, representing the spectrum of tumor-inducing factors and tumor locations. The imaging analysis approach of reporter genes driven by AFP enhancer/promoter is presented for these different HCC mouse models. Such molecular imaging can provide longitudinal information about carcinogenesis and tumor progression. We expect that clinical application of AFP-targeted reporter gene expression imaging systems will be useful for the detection of AFP-expressing HCC tumors and screening of increased/decreased AFP levels due to disease or drug treatment.展开更多
文摘Purpose: Multi-tracer neuroimaging is widely used for the diagnosis, radiotherapy, and neuro-surgery of brain gliomas. Anatomical and functional information is important to avoid having neurological deficits induced during the resection or radiation therapy of brain gliomas. The aim of this study was to investigate presurgical anatomical labeling of brain gliomas on FLT and FET using statistical probabilistic anatomic maps (SPAM), which are images of cerebral cortical, cerebellar, and subcortical volumes of interest (VOIs). Methods: FDG, FLT, and FET PET scans were acquired. FLT and FET PET images were coregistered to the FDG PET images, which were then spatially normalized onto the target brain. An inverse spatial normalization parameter was calculated and applied to SPAM. For the anatomical labeling of brain glioma regions, the volumes of brain gliomason FLT and FET images were extracted using segmentation. Probabilistic information of the glioma region was then calculated using SPAM and the segmented glioma volumes. SPM and an in-house program were used for image processing. Results: The probability of SPAM labeling a brain glioma region could be extracted using the inverse normalized SPAM and segmented glioma regions. In a sample case, the probabilistic anatomical region of the glioma included 21% of the postcentral gyrus, 12% of the superior parietal gyrus, and 6% of the angular gyrus. Conclusion: Anatomical information about brain gliomas could be extracted using SPAM. This proposed method would be optional for presurgical mapping, to avoid an additional functional mapping study that might otherwise be necessary to avoid producing neurological deficits.
文摘Objective: Although Iodine-125 (125I) has been widely used for in vitro studies because of its relatively long half-life (60.1 days), 125I imaging is limited because of its low energy (27 - 35 keV), even in an animal-dedicated system. In this study, imaging characteristics of 125I were assessed using a small animal-dedicated imaging system and clinical scanner. Methods: Using the Siemens Inveon and Siemens Symbia TruePoint systems, imaging characteristics such as resolution, sensitivity, and image quality were compared. Mouse high resolution (MHR-0.5), mouse general purpose (MGP-1.0), and mouse high sensitivity (MHS-2.0) collimators were used for the Inveon scanner, and low energy high-resolution (LEHR) and low energy all-purpose (LEAP) collimators were used for the Symbia TruePoint. For animal imaging, 16.8 MBq of 125I was administered to BALB/c mice intravenously, and the planar image and single-photon emission computed tomography (SPECT) were obtained using both scanners. Results: The resolution of 125I for the Inveon scanner was 3.98 mm full width at half maximum (FWHM) at a 30-mm distance with the MHR-0.5 collimator, and the value of Symbia scanner was 8.72 mm FWHM at a 30-mm distance with the LEHR collimator. The sensitivity of 125I for the Inveon scanner was 21.87 cps/MBq, and the value for the clinical scanner was 30.55 cps/MBq. The planar images of mice were successfully obtained at the level of evaluating specific binding in both scanners. Conclusion: 125I small animal imaging can be achieved with a clinical scanner. This result may enhance the utilization of 125I small animal imaging using a clinical scanner.
基金Supported by Korea Science and Engineering Foundation,No.2012M2A2A7013480 and No.2013M2C2A1074238
文摘Hepatocellular carcinoma(HCC) is one of the most common cancers in Eastern Asia, and its incidence is increasing globally. Numerous experimental models have been developed to better our understanding of the pathogenic mechanism of HCC and to evaluate novel therapeutic approaches. Molecular imaging is a convenient and up-to-date biomedical tool that enables the visualization, characterization and quantification of biologic processes in a living subject. Molecular imaging based on reporter gene expression, in particular, can elucidate tumor-specific events or processes by acquiring images of a reporter gene's expression driven by tumor-specific enhancers/promoters. In this review, we discuss the advantages and disadvantages of various experimental HCC mouse models and we present in vivo images of tumorspecific reporter gene expression driven by an alphafetoprotein(AFP) enhancer/promoter system in a mouse model of HCC. The current mouse models of HCC development are established by xenograft, carcinogen induction and genetic engineering, representing the spectrum of tumor-inducing factors and tumor locations. The imaging analysis approach of reporter genes driven by AFP enhancer/promoter is presented for these different HCC mouse models. Such molecular imaging can provide longitudinal information about carcinogenesis and tumor progression. We expect that clinical application of AFP-targeted reporter gene expression imaging systems will be useful for the detection of AFP-expressing HCC tumors and screening of increased/decreased AFP levels due to disease or drug treatment.
