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Objectives: To investigated the correlation between sinonasal computed tomography (SNCT) findings and sinonasal symptoms, genotype, chronic colonization by Pseudomonas aeruginosa, forced expiratory volume in the first second (FEV1...
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Objectives: To investigated the correlation between sinonasal computed tomography (SNCT) findings and sinonasal symptoms, genotype, chronic colonization by Pseudomonas aeruginosa, forced expiratory volume in the first second (FEV1), body mass index (BMI), Shwachman-Kulczycki (SK) score, and Bhalla score in patients with cystic fibrosis.
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Over the past two decades, computed tomography, CT, has become one of the most significant imaging modalities in clinical medicine. The hardware and software innovations responsible for the advances in image quality have also resu...
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Over the past two decades, computed tomography, CT, has become one of the most significant imaging modalities in clinical medicine. The hardware and software innovations responsible for the advances in image quality have also resulted in the desire to incorporate CT into mummy research. Although manufacturers have endeavored to simplify the operation of the equipment, the intended use has been primarily living humans and not dehydrated remains. However, with a thorough understanding of the underlying principles of the modality, including the limitations, and the consequences of the manipulation of technical settings, satisfactory results can be obtained. Anat Rec, 298:1088-1098, 2015. (c) 2015 Wiley Periodicals, Inc.
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Current positron emission tomography/computed tomography (PET/CT) and single photon emission CT (SPECT)/CT displays have major drawbacks, in that the CT only shows one tissue type at a time, which leads to a suboptimal fusion disp...
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Current positron emission tomography/computed tomography (PET/CT) and single photon emission CT (SPECT)/CT displays have major drawbacks, in that the CT only shows one tissue type at a time, which leads to a suboptimal fusion display. We developed a multipurpose CT level/window aiming at enhancing fusion display. A total of thirty CT examinations as part of fluorodeoxyglucose PET/CT examinations (15 were open source from the OsiriX website and 15 from our PET facility) and the open-source software MIPAV were used. During the development phase, a nuclear medicine physician manually modified the lookup table in a way that preserved the soft tissue contrast as well as enhanced the lung and bone tissue as much as possible. The developed multipurpose CT window was used in the subsequent validation phase and scored by two nuclear medicine physicians, who scored the image quality based on a 3-point score. Descriptive statistics was used to summarize the visual scores. The multipurpose CT window is a composite of several segments of linear CT levels/windows and contains an inverted linear level/window in the low range of Hounsfield unit designed to enhance lung/soft tissue contrast. In doing so, the multipurpose CT window preserves the high soft tissue contrast; the visualization of the lung parenchyma is satisfactory; the contrast for the bone tissue is improved but remains suboptimal when compared with conventional bone window. The multipurpose CT window was found to be “very useful” (median score 3; 95% confidence interval [CI] 2.0–3.0) for the purpose of fusion with functional imaging, with a prevalence asymmetry index 0.97 (95% CI 0.83–1.0). The multipurpose CT window was developed for image fusion and is not intended for diagnostic purposes. It shows favorable similarities to conventional CT windows with only minor artifacts and allows for enhanced visualization of fused PET/CT and SPECT/CT images. The multipurpose CT window is particularly valuable for case review/demonstrations on standard personal computers and handheld devices (smartphones, tablets).
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Monte Carlo methods are extensively used in Nuclear Medicine to tackle a variety of problems that are diffi- cult to study by an experimental or analytical approach. A review of the most recent tools allowing application of Monte ...
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Monte Carlo methods are extensively used in Nuclear Medicine to tackle a variety of problems that are diffi- cult to study by an experimental or analytical approach. A review of the most recent tools allowing application of Monte Carlo methods in single photon emission tomography (SPET) and positron emission tomography (PET) is presented. To help potential Monte Carlo users choose a code, we present advantages and disadvan- tages of the different types of Monte Carlo codes cur- rently available for SPET and PET, discuss common and specific features of the codes, classify the codes with respect to these features, comment key properties for a code to be appropriate for a given purpose and, at last, we consider the possibility of going towards a stan- dardisation of the description of the codes which could facilitate their comparison.
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This article reviews the state of the art of PET/CT applications in radiotherapy, specifically its use in disease staging, patient selection, treatment planning and treatment evaluation. Diseases for which radiotherapy with radica...
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This article reviews the state of the art of PET/CT applications in radiotherapy, specifically its use in disease staging, patient selection, treatment planning and treatment evaluation. Diseases for which radiotherapy with radical intent is indicated will be considered, as well as those in which PET/CT may actually change the course of disease. The methodological and technological aspects of PET/CT in radiotherapy are discussed, focusing on the problem of target volume definition with CT and PET functional imaging and the problem of tumor motion with respect to imaging and dose delivery.
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This article discusses attenuation correction strategies in positron emission tomography/computed tomography (PET/CT) and 4-dimensional PET/CT imaging. Average CT scan derived from averaging the high temporal resolution CT images ...
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This article discusses attenuation correction strategies in positron emission tomography/computed tomography (PET/CT) and 4-dimensional PET/CT imaging. Average CT scan derived from averaging the high temporal resolution CT images is effective in improving the registration of the CT and the PET images and quantification of the PET data. It underscores list-mode data acquisition in 4-dimensional PET, and introduces 4-dimensional CT, popular in thoracic treatment planning, to 4-dimensional PET/CT.
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Computed tomography (CT) technology has rapidly evolved since its introduction in the 1970s. It is a highly important diagnostic tool for clinicians as demonstrated by the significant increase in utilization over several decades. ...
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Computed tomography (CT) technology has rapidly evolved since its introduction in the 1970s. It is a highly important diagnostic tool for clinicians as demonstrated by the significant increase in utilization over several decades. However, much of the effort to develop and advance CT applications has been focused on improving visual sensitivity and reducing radiation dose. In comparison to these areas, improvements in quantitative CT have lagged behind. While this could be a consequence of the technological limitations of conventional CT, advanced dual‐energy CT (DECT) and photon‐counting detector CT (PCD‐CT) offer new opportunities for quantitation. Routine use of DECT is becoming more widely available and PCD‐CT is rapidly developing. This review covers efforts to address an unmet need for improved quantitative imaging to better characterize disease, identify biomarkers, and evaluate therapeutic response, with an emphasis on multi‐energy CT applications. The review will primarily discuss applications that have utilized quantitative metrics using both conventional and DECT, such as bone mineral density measurement, evaluation of renal lesions, and diagnosis of fatty liver disease. Other topics that will be discussed include efforts to improve quantitative CT volumetry and radiomics. Finally, we will address the use of quantitative CT to enhance image‐guided techniques for surgery, radiotherapy and interventions and provide unique opportunities for development of new contrast agents.
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BACKGROUND AND PURPOSE: Distal medium vessel occlusions (DMVOs) are increasingly considered for endovascular thrombectomy but are difficult to detect on computed tomography angiography (CTA). We aimed to determine whether time-to-...
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BACKGROUND AND PURPOSE: Distal medium vessel occlusions (DMVOs) are increasingly considered for endovascular thrombectomy but are difficult to detect on computed tomography angiography (CTA). We aimed to determine whether time-to-maximum of tissue residue function (Tmax) maps, derived from CT perfusion, can be used as a triage screening tool to accurately and rapidly identify patients with DMVOs.
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Purpose of Review The purpose of this paper is to review the current role of computed tomography (CT) in the imaging of left ventricular assist devices (LVAD). Recent Findings Recent studies have highlighted the prognostic role of...
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Purpose of Review The purpose of this paper is to review the current role of computed tomography (CT) in the imaging of left ventricular assist devices (LVAD). Recent Findings Recent studies have highlighted the prognostic role of measuring skeletal muscle CT attenuation in predicting adverse LVAD outcomes. CT is also useful for evaluation of inflow cannula malposition, and outflow graft complications such as obstruction and kinking. In addition,F-18-fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET-CT) has been shown to be of value in evaluation of suspected LVAD infection. Newer CT techniques such as dual-energy CT and metal artifact reduction algorithms can potentially generate better quality CT images, though currently there is no high-quality published literature on their use in LVAD imaging. CT is a useful technique as part of a multi-modality approach in the evaluation of LVADs and associated complications.
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Pulmonary sclerosing pneumocytoma (PSP) is a benign tumor originating from primitive respiratory epithelium which tends to present as an asymptomatic solitary lesion in the periphery of the lung. It primarily occurs in women, with...
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Pulmonary sclerosing pneumocytoma (PSP) is a benign tumor originating from primitive respiratory epithelium which tends to present as an asymptomatic solitary lesion in the periphery of the lung. It primarily occurs in women, with a 5:1 ratio of female to male, and in East Asian populations. We describe a rare case of a gallium-68 (68Ga)-DOTATATE avid PSP in a middle-aged man of North African ancestry. Contrast-enhanced computed tomography (CT) revealed an enhancing ovoid 2-cm solid lesion within the periphery of the left upper lobe abutting the superior portion of the lateral left ventricular wall. A fluorine-18-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) demonstrated low-level FDG uptake, but a 68Ga-DOTATATE PET/CT showed avid tracer uptake, concerning for a carcinoid tumor. The lesion was surgically excised, and the histopathologic analysis revealed the typical morphologic and histochemical markers of a PSP. We conclude that, although rare, PSP can be a differential consideration when evaluating a 68Ga-DOTATATE-avid solitary lung nodule concerning for carcinoid tumor, in all genders and in ethnicities other than East Asian.
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