Browsing by Subject "PET/CT"

Now showing 1 - 5 of 5
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    Motion correction of PET/CT images
    (2017) Chong Chie, Juan Antonio Kim Hoo; Salama, Paul; Territo, Paul
    The advances in health care technology help physicians make more accurate diagnoses about the health conditions of their patients. Positron Emission Tomography/Computed Tomography (PET/CT) is one of the many tools currently used to diagnose health and disease in patients. PET/CT explorations are typically used to detect: cancer, heart diseases, disorders in the central nervous system. Since PET/CT studies can take up to 60 minutes or more, it is impossible for patients to remain motionless throughout the scanning process. This movements create motion-related artifacts which alter the quantitative and qualitative results produced by the scanning process. The patient's motion results in image blurring, reduction in the image signal to noise ratio, and reduced image contrast, which could lead to misdiagnoses. In the literature, software and hardware-based techniques have been studied to implement motion correction over medical files. Techniques based on the use of an external motion tracking system are preferred by researchers because they present a better accuracy. This thesis proposes a motion correction system that uses 3D affine registrations using particle swarm optimization and an off-the-shelf Microsoft Kinect camera to eliminate or reduce errors caused by the patient's motion during a medical imaging study.
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    NaF-PET Imaging of Atherosclerosis Burden
    (MDPI, 2023-01-30) Høilund-Carlsen, Poul F.; Piri, Reza; Gerke, Oke; Sturek, Michael; Werner, Thomas J.; Revheim, Mona-Elisabeth; Alavi, Abass; Anatomy, Cell Biology and Physiology, School of Medicine
    The method of 18F-sodium fluoride (NaF) positron emission tomography/computed tomography (PET/CT) of atherosclerosis was introduced 12 years ago. This approach is particularly interesting because it demonstrates microcalcification as an incipient sign of atherosclerosis before the development of arterial wall macrocalcification detectable by CT. However, this method has not yet found its place in the clinical routine. The more exact association between NaF uptake and future arterial calcification is not fully understood, and it remains unclear to what extent NaF-PET may replace or significantly improve clinical cardiovascular risk scoring. The first 10 years of publications in the field were characterized by heterogeneity at multiple levels, and it is not clear how the method may contribute to triage and management of patients with atherosclerosis, including monitoring effects of anti-atherosclerosis intervention. The present review summarizes findings from the recent 2¾ years including the ability of NaF-PET imaging to assess disease progress and evaluate response to treatment. Despite valuable new information, pertinent questions remain unanswered, not least due to a pronounced lack of standardization within the field and of well-designed long-term studies illuminating the natural history of atherosclerosis and effects of intervention.
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    Normal Patterns and Pitfalls of FDG Uptake in the Head and Neck
    (Elsevier, 2019) Gray, Benjamin R.; Koontz, Nicholas A.; Radiology and Imaging Sciences, School of Medicine
    In order to avoid misdiagnoses, medical imagers should be familiar with the normal patterns and distribution of fluorodeoxyglucose (FDG) activity within the head and neck, as well as the pathophysiology and imaging-findings of common diagnostic pitfalls related to incidental FDG-avid lesions. The purpose of this article is to provide an image-rich review of the normal patterns of FDG uptake in the head and neck, help differentiate benign from malignant incidentally found FDG-avid foci, and detail important “don't miss” hypometabolic head and neck lesions on positron emission tomography/computed tomography and positron emission tomography/magnetic resonance imaging.
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    PET/MRI vs PET/CT in Head and Neck Imaging: When, Why, and How?
    (Elsevier, 2019) Ryan, Joshua L.; Aaron, Vasantha D.; Sims, Justin B.; Radiology and Imaging Sciences, School of Medicine
    The increasing availability of hybrid PET/MRI systems has led to a breadth of new publications and opportunities for use of PET/MRI. While PET/CT has been a valuable tool for oncologic staging, including head and neck malignancy, there are several theoretical and practical advantages a PET/MRI system would have over PET/CT in head and neck imaging. This review article discusses the established role of PET/CT, early evidence for the role of PET/MRI, and protocol considerations for both PET/CT and PET/MRI as they apply to head and neck imaging.
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    Whole body metabolic tumor volume is a prognostic marker in patients with newly diagnosed stage 3B non-small cell lung cancer, confirmed with external validation
    (SpringerOpen, 2017) Dashevsky, Brittany Z.; Zhang, Chenpeng; Yan, Li; Yuan, Cindy; Xiong, Lingyun; Liu, Yongmei; Liu, Haiyan; Spring Kong, Feng-Ming; Pu, Yonglin; Medical and Molecular Genetics, School of Medicine
    Purpose: TNM Stage 3B encompasses a wide range of primary tumor and nodal metastatic tumor burden. This study aimed to evaluate the prognostic value of quantitative FDG PET/CT parameters in patients with newly diagnosed Stage 3B Non-Small Cell Lung Cancer (NSCLC). Materials and Methods: Institutional review board approved retrospective study identified patients diagnosed with Stage 3B NSCLC (8th edition TNM classification) on baseline FDG PET/CT at two medical centers (Medical centers A and B), between Feb 2004 and Dec 2014. Patients were excluded if they had prior NSCLC treatment or recent diagnosis of a second primary cancer. Quantitative FDG PET/CT parameters including whole body metabolic tumor volume (MTVwb), total lesion glycolysis (TLGwb), and maximum standardized uptake value (SUVmaxwb) were measured from baseline PET/CT using Edge method with Mimvista software. The primary endpoint was overall survival (OS). Cox proportional hazard regression and Kaplan-Meier overall survival analyses were used to test for an association between OS and quantitative FDG PET/CT parameters. The distributions of MTVwb, TLGwb, SUVmaxwb were skewed, so a natural logarithm transformation was applied and the transformed variables [(ln(MTVwb), ln(TLGwb), and ln(SUVmaxwb)] were used in the analysis. Results: The training set included 110 patients from center A with Stage 3B NSCLC. 78.2% of patients expired during follow-up. Median OS was 14 months. 1-year, 2-year, and 5-year OS was 56.5%, 34.6% and 13.9%, respectively. Univariate Cox regression analysis showed no significant difference in OS on the basis of age, gender, histology, ln(TLGwb), or ln(SUVmaxwb). ln(MTVwb) was positively associated with OS [hazard ratio (HR) of 1.23, p = 0.037]. This association persisted on multivariate Cox regression analysis (HR 1.28, p = 0.043), with adjustments for age, gender, treatment and tumor histology. External validation with 44 patients from center B confirmed increasing MTVwb was associated significantly worse OS. An MTVwb cut-off point of 85.6 mL significantly stratified Stage 3B NSCLC patient prognosis. Conclusion: MTVwb is a prognostic marker for OS in patients with Stage 3B NSCLC, independent of age, gender, treatment, and tumor histology.