118,809 results match your criteria imaging pet

A positron emission tomography study of the serotonin1B receptor effect of electroconvulsive therapy for severe major depressive episodes.

J Affect Disord 2021 Jul 17;294:645-651. Epub 2021 Jul 17.

Department of Neuropsychiatry, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan.

Background: Electroconvulsive therapy (ECT) is an effective treatment for depressive disorders, although its molecular mechanism of action is unknown. The serotonin 1B (5-HT) receptor is a potential target for treatment of depression and low 5-HT receptor binding in limbic regions has been reported in previous positron emission tomography (PET) studies of depression.

Methods: The objective of this longitudinal PET study was to examine the effect of ECT for depression on 5-HT receptor binding. Read More

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Positron emission tomographic imaging in drug discovery.

Drug Discov Today 2021 Jul 28. Epub 2021 Jul 28.

Lee Kong Chian School of Medicine, Nanyang Technological University, 59 Nanyang Drive, Singapore 636921; Cognitive Neuroimaging Centre, 59 Nanyang Drive, Nanyang Technological University, Singapore 636921, Singapore; Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institute and Stockholm County Council, SE-171 76 Stockholm, Sweden.

Positron emission tomography (PET) is an extensively used nuclear functional imaging technique, especially for central nervous system (CNS) and oncological disorders. Currently, drug development is a lengthy and costly pursuit. Imaging with PET radiotracers could be an effective way to hasten drug discovery and advancement, because it facilitates the monitoring of key facets, such as receptor occupancy quantification, drug biodistribution, pharmacokinetic (PK) analyses, validation of target engagement, treatment monitoring, and measurement of neurotransmitter concentrations. Read More

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Strategies for Multivariate Analyses of Imaging Genetics Study in Alzheimer's disease.

Neurosci Lett 2021 Jul 28:136147. Epub 2021 Jul 28.

School of Computer Science and Technology, Hangzhou Dianzi University, Hangzhou, Zhejiang, 310018, China; Key Laboratory of Intelligent Image Analysis for Sensory and Cognitive Health, Ministry of Industry and Information Technology of China, Hangzhou, Zhejiang, 310018, China.

Alzheimer's disease (AD) is an incurable neurodegenerative disease primarily affecting the elderly population. Early diagnosis of AD is critical for the management of this disease. Imaging genetics examines the influence of genetic variants (i. Read More

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Characterization of endogenous bile acid composition in individuals with cold-activated brown adipose tissue.

Mol Cell Endocrinol 2021 Jul 28:111403. Epub 2021 Jul 28.

Division of Endocrinology and Metabolism, Department of Medicine III, Medical University of Vienna, Vienna, Austria. Electronic address:

Introduction: Bile acid signaling has been suggested to promote BAT activity in various experimental models. However, little is known if and how physiologic bile acid metabolism is linked to BAT function in humans. Here we investigated the association between BAT activity and circulating bile acid concentrations in lean and obese individuals. Read More

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Toward PET imaging of the dynamic phenotypes of microglia.

Clin Exp Immunol 2021 Jul 31. Epub 2021 Jul 31.

Amsterdam UMC, Vrije Universiteit, Dept. Radiology and Nuclear Medicine, Tracer Center Amsterdam, De Boelelaan 1117, Amsterdam, The Netherlands.

There is increasing evidence showing the heterogeneity of microglia activation in neuroinflammatory and neurodegenerative diseases. It has been hypothesized that pro-inflammatory microglia are detrimental and contribute to disease progression, while anti-inflammatory microglia play a role in damage repair and remission. The development of therapeutics targeting the deleterious glial activity and modulating it into a regenerative phenotype heavily relies on a better understanding of the microglia dynamics during disease progression and the ability to monitor therapeutic outcome in vivo. Read More

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Structural and functional neuroimaging of late-life depression: a coordinate-based meta-analysis.

Brain Imaging Behav 2021 Jul 31. Epub 2021 Jul 31.

Institute of Medical Science and Technology, Shahid Beheshti University, Tehran, Iran.

Several neuroimaging studies have investigated localized aberrations in brain structure, function or connectivity in late-life depression, but the ensuing results are equivocal and often conflicting. Here, we provide a quantitative consolidation of neuroimaging in late-life depression using coordinate-based meta-analysis by searching multiple databases up to March 2020. Our search revealed 3252 unique records, among which we identified 32 eligible whole-brain neuroimaging publications comparing 674 patients with 568 controls. Read More

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Optimisation of CT protocols in PET-CT across different scanner models using different automatic exposure control methods and iterative reconstruction algorithms.

EJNMMI Phys 2021 Jul 31;8(1):58. Epub 2021 Jul 31.

King's College London & Guy's and St Thomas' PET Centre, School of Biomedical Engineering and Imaging Sciences, King's College London, St Thomas' Hospital, Westminster Bridge Road, London, SE1 7EH, UK.

Background: A significant proportion of the radiation dose from a PET-CT examination is dependent on the CT protocol, which should be optimised for clinical purposes. Matching protocols on different scanners within an imaging centre is important for the consistency of image quality and dose. This paper describes our experience translating low-dose CT protocols between scanner models utilising different automatic exposure control (AEC) methods and reconstruction algorithms. Read More

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Multiphoton Deep-Tissue Imaging of Micrometastases and Disseminated Cancer Cells Using Conjugates of Quantum Dots and Single-Domain Antibodies.

Methods Mol Biol 2021 ;2350:105-123

Laboratoire de Recherche en Nanosciences, LRN-EA4682, Université de Reims Champagne-Ardenne, Reims, France.

Early detection of malignant tumors, micrometastases, and disseminated tumor cells is one of the effective way of fighting cancer. Among the many existing imaging methods like computed tomography (CT), ultrasound (US), magnetic resonance imaging (MRI), positron emission tomography (PET), and single-photon emission computed tomography (SPECT), optical imaging with fluorescent probes is one of the most promising alternatives because it is fast, inexpensive, safe, sensitive, and specific. However, traditional fluorescent probes, based on organic fluorescent dyes, suffer from the low signal-to-noise ratio. Read More

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January 2021

Feasibility and application of trimetazidine in F-FDG PET myocardial metabolic imaging of diabetic mellitus patients with severe coronary artery disease: A prospective, self-controlled study.

J Nucl Cardiol 2021 Jul 30. Epub 2021 Jul 30.

Department of Nuclear Medicine, The Third Affiliated Hospital of Soochow University, Changzhou, 213003, Jiangsu, China.

Background: F-FDG PET myocardial metabolic imaging (MMI) is sometimes uninterpretable due to background activity from uncontrolled glucose homeostasis in diabetic mellitus (DM) patients. Trimetazidine is an oral medication that promotes the transformation of myocardial energy supply from free fatty acids to glucose. We aimed to investigate the feasibility and application of trimetazidine in F-FDG PET MMI of DM patients. Read More

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F-FDG PET/CT imaging features of Cardiac Arrhythmia - induced by Panitumumab.

J Nucl Med Technol 2021 Jul 30. Epub 2021 Jul 30.

Rush University Medical Center, United States.

Panitumumab is a new humanized anti-epidermal growth factor receptor (EGFR) monoclonal antibody (mAb) approved for the treatment of advanced colorectal cancer. There is an increase in the use of this drug due to a good response rate and possible secondary resection in advance colorectal cancer. Here we present F-FDG PET/CT imaging findings of cardiac arrhythmia in a patient receiving Panitumumab for the treatment of metastatic infiltrating rectal adenocarcinoma. Read More

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Decay correction for quantitative myocardial PET perfusion in established PET scanners: a potentially overlooked source of errors.

Robert M Bober

J Nucl Med Technol 2021 Jul 30. Epub 2021 Jul 30.

John Ochsner Heart and Vascular Institute, United States.

Quantitative myocardial PET perfusion requires decay correction of the dynamic datasets to ensure measured activity reflects true physiology and not radiotracer decay or duration of frame intervals. Decay correction is typically performed by the PET camera system and the exact algorithm is buried within the settings and assumed to be correct for quantitative perfusion data. For quantitative myocardial perfusion, sequential dynamic images should be decay corrected to the activity at the mid time point of the first scan in the sequence. Read More

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Immune checkpoint inhibitor related adverse effects and FDG PET/CT findings.

J Nucl Med Technol 2021 Jul 30. Epub 2021 Jul 30.

Trakya university Faculty of Medicine, Department of Nuclear Medicine, Turkey.

Immune check-point inhibitor (ICI) treatments activate the T-cells against tumor. Activated T-cells not only attack the tumor but also healthy cells, causing an autoimmune reaction in various tissues. These immune related adverse effects (IRAE) cause F-fluorodeoxyglucose (FDG) uptake in various tissues due to inflammation. Read More

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Lung Perfusion Scintigraphy in Early Post-COVID-19: A Single Centre Retrospective Study.

J Nucl Med Technol 2021 Jul 30. Epub 2021 Jul 30.

All India Institute of Medical Sciences, Raipur, India.

The incidence of thromboembolic complications in COVID-19 infection is well-recognized. The present study retrospectively evaluated the prevalence and distribution of lung perfusion defects in early post-COVID-19 patients with hypoxia and was aimed to identify the risk factors for mismatched perfusion defects. We retrospectively analyzed the single-photon emission computed tomography/computed tomography (SPECT/CT) of 54 early post-COVID-19 patients (male: 44). Read More

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Rare Multi-system Histiocytic Sarcoma on F18-FDG PET/CT.

J Nucl Med Technol 2021 Jul 30. Epub 2021 Jul 30.

Mayo Clinic, United States.

Histiocytic sarcoma (HS) is a rare malignancy with morphological and immunophenotypic features of histocytes. We present a case of histiocytic sarcoma with multisystem involvement, including an obstructing pancreatic head mass. F18-FDG PET/CT is a valuable tool in staging and assessment of response to therapy in this rare entity. Read More

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Hepatic blood volume is decreased in patients with cirrhosis and does not decrease further after a meal like in healthy persons.

Scand J Gastroenterol 2021 Jul 30:1-5. Epub 2021 Jul 30.

Department of Hepatology & Gastroenterology, Aarhus University Hospital, Aarhus, Denmark.

Background & Aims: The aim was to measure fractional hepatic blood volume (HBV) and hepatic blood flow (HBF) before and after a meal in patients with cirrhosis ( = 7) and healthy persons ( = 6).

Methods: Catheters were placed in a radial artery and a hepatic vein for blood sampling and a peripheral vein for indocyanine green (ICG) infusion. A 6-min positron emission tomography (PET) liver scan was performed after inhalation of 1000 MBq O-CO and repeated after ingestion of a standard meal. Read More

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Detecting and classifying neurotransmitter signals from ultra-high sensitivity PET data: the future of molecular brain imaging.

Phys Med Biol 2021 Jul 30. Epub 2021 Jul 30.

Biomedical Engineering, Yale University, New Haven, Connecticut, UNITED STATES.

Efforts to build the next generation of brain PET scanners are underway. It is expected that a new scanner (NS) will offer an order-of-magnitude improvement in sensitivity to counts compared to the current state-of-the-art, Siemens HRRT. Our goal was to explore the use of the anticipated increased sensitivity in combination with the linear-parametric neurotransmitter PET (lp-ntPET) model to improve detection and classification of transient dopamine (DA) signals. Read More

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Hybrid model of photon propagation based on the analytical and Monte Carlo methods for a dual-head PET system.

Phys Med Biol 2021 Jul 30. Epub 2021 Jul 30.

School of Life Science and Technology, Xidian University, Xian, 710071, CHINA.

The construction of photon propagation has a close relationship with the quality of reconstructed images. The classical Monte Carlo (MC) based method can model the photon propagation precisely, but it is time-consuming. The analytical method can often quickly construct a model, but its precision is a problem. Read More

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Hepatic actinomycosis after total pancreatectomy: A case report.

Int J Surg Case Rep 2021 Jul 20;85:106212. Epub 2021 Jul 20.

Department of Surgery, Kansai Medical University, Osaka, Japan.

Introduction And Importance: Hepatic actinomycosis (HA) is a rare infection mimicking a malignancy. HA after total pancreatectomy for a pancreatic tumor has not been reported.

Case Presentation: A 70-year-old woman with a history of gastrectomy and sigmoidectomy for benign lesions, underwent a total pancreatectomy for a non-invasive, intraductal papillary mucinous carcinoma (IPMC). Read More

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Visualization of hypermetabolism in the ventral visual pathway by FDG-PET in the Charles Bonnet syndrome.

Clin Neurol Neurosurg 2021 Jul 21;208:106832. Epub 2021 Jul 21.

Department of Neurosurgery, Osaka Rosai Hospital, 1179-3 Nagasone-Cho, Sakai, Osaka 591-8025, Japan.

A 74-year-old man presented with complex visual hallucinations with a left inferior quadrantanopia. The characteristics of the visual hallucinations met the criteria for the Charles Bonnet syndrome. Brain magnetic resonance imaging (MRI) revealed a right occipital falx meningioma. Read More

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Entering a new era of the identification and characterization of myocardial ischemic burden with O-water PET?

Int J Cardiol 2021 Jul 27. Epub 2021 Jul 27.

Cardiovascular Division, John T. Milliken Department of Internal Medicine, Washington University School of Medicine, St. Louis, MO, USA.

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Disease Burden Affects Aging Brain Function.

J Gerontol A Biol Sci Med Sci 2021 Jul 30. Epub 2021 Jul 30.

Intramural Research Program, National Institute on Aging, NIH.

Background: Most older adults live with multiple chronic disease conditions, yet the effect of multiple diseases on brain function remains unclear.

Methods: We examine the relationship between disease multimorbidity and brain activity using regional cerebral blood flow (rCBF) 15O-water PET scans from 97 cognitively normal participants (mean baseline age 76.5) in the Baltimore Longitudinal Study of Aging (BLSA). Read More

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Mycobacterial lymphadenitis without granuloma formation in a patient with anti-interferon-gamma antibodies.

Int J Hematol 2021 Jul 30. Epub 2021 Jul 30.

Department of Hematology, Hyogo Prefectural Nishinomiya Hospital, 13-9, Rokutanji-cho, Nishinomiya, Hyogo, 662-0918, Japan.

A previously healthy 49-year-old Japanese woman presented with cervical lymph node swelling and tenderness. Lymph node biopsy revealed reactive lymphadenitis without granulomas. No malignant cells were found, and no acid-fast positive bacilli were identified by Ziehl-Neelsen staining. Read More

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Radiologic Imaging Modalities for Colorectal Cancer.

Dig Dis Sci 2021 Jul 30. Epub 2021 Jul 30.

Department of Radiology, Jinshan Hospital, Fudan University, 1508 Longhang Rd., Jinshan District, Shanghai, 201508, China.

Background: Studies reported various diagnostic value of radiologic imaging modalities for diagnosis and management of colorectal cancer (CRC).

Aims: To summary the diagnosis and management of CRC using computed tomography colonography (CTC), magnetic resonance colonography (MRC), and positron emission tomography (PET)/computed tomography (CT).

Methods: Comprehensive literature searches were conducted in PubMed, EmBase, and the Cochrane library for studies published before April 2021. Read More

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Optimization of SPECT/CT imaging protocols for quantitative and qualitative Tc SPECT.

EJNMMI Phys 2021 Jul 30;8(1):57. Epub 2021 Jul 30.

Department of Radiology and Nuclear Medicine, University Hospital Magdeburg, Magdeburg, Germany.

Background: The introduction of hybrid SPECT/CT devices enables quantitative imaging in SPECT, providing a methodological setup for quantitation using SPECT tracers comparable to PET/CT. We evaluated a specific quantitative reconstruction algorithm for SPECT data using a Tc-filled NEMA phantom. Quantitative and qualitative image parameters were evaluated for different parametrizations of the acquisition and reconstruction protocol to identify an optimized quantitative protocol. Read More

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Diagnostic accuracy of glabellar tap sign for Parkinson's disease.

J Neural Transm (Vienna) 2021 Jul 30. Epub 2021 Jul 30.

Clinical Neurosciences, University of Turku, Turku, Finland.

Glabellar tap or reflex (GR) is an old bedside clinical test used in the diagnostics of Parkinson's disease (PD), but its diagnostic value is unclear. This study examines the diagnostic validity and reliability of GR in PD in relation to brain dopaminergic activity. GR was performed on 161 patients with PD, 47 patients with essential tremor (ET) and 40 healthy controls immediately prior to dopamine transporter (DAT) [I]FP-CIT SPECT scanning. Read More

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Harmonisation of PET imaging features with different amyloid ligands using machine learning-based classifier.

Eur J Nucl Med Mol Imaging 2021 Jul 30. Epub 2021 Jul 30.

Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, 06351, Seoul, South Korea.

Purpose: In this study, we used machine learning to develop a new method derived from a ligand-independent amyloid (Aβ) positron emission tomography (PET) classifier to harmonise different Aβ ligands.

Methods: We obtained 107 paired F-florbetaben (FBB) and F-flutemetamol (FMM) PET images at the Samsung Medical Centre. To apply the method to FMM ligand, we transferred the previously developed FBB PET classifier to test similar features from the FMM PET images for application to FMM, which in turn developed a ligand-independent Aβ PET classifier. Read More

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A 3D deep learning model to predict the diagnosis of dementia with Lewy bodies, Alzheimer's disease, and mild cognitive impairment using brain 18F-FDG PET.

Eur J Nucl Med Mol Imaging 2021 Jul 30. Epub 2021 Jul 30.

Department of Clinical Physiology, Department of Health, Medicine and Caring Sciences, Linköping University, Linköping, Sweden.

Purpose: The purpose of this study is to develop and validate a 3D deep learning model that predicts the final clinical diagnosis of Alzheimer's disease (AD), dementia with Lewy bodies (DLB), mild cognitive impairment due to Alzheimer's disease (MCI-AD), and cognitively normal (CN) using fluorine 18 fluorodeoxyglucose PET (18F-FDG PET) and compare model's performance to that of multiple expert nuclear medicine physicians' readers.

Materials And Methods: Retrospective 18F-FDG PET scans for AD, MCI-AD, and CN were collected from Alzheimer's disease neuroimaging initiative (556 patients from 2005 to 2020), and CN and DLB cases were from European DLB Consortium (201 patients from 2005 to 2018). The introduced 3D convolutional neural network was trained using 90% of the data and externally tested using 10% as well as comparison to human readers on the same independent test set. Read More

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Co-clinical FDG-PET radiomic signature in predicting response to neoadjuvant chemotherapy in triple-negative breast cancer.

Eur J Nucl Med Mol Imaging 2021 Jul 30. Epub 2021 Jul 30.

Department of Radiology, Washington University School of Medicine, St. Louis, MO, USA.

Purpose: We sought to exploit the heterogeneity afforded by patient-derived tumor xenografts (PDX) to first, optimize and identify robust radiomic features to predict response to therapy in subtype-matched triple negative breast cancer (TNBC) PDX, and second, to implement PDX-optimized image features in a TNBC co-clinical study to predict response to therapy using machine learning (ML) algorithms.

Methods: TNBC patients and subtype-matched PDX were recruited into a co-clinical FDG-PET imaging trial to predict response to therapy. One hundred thirty-one imaging features were extracted from PDX and human-segmented tumors. Read More

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Emerging methods for prostate cancer imaging: evaluating cancer structure and metabolic alterations more clearly.

Mol Oncol 2021 Jul 30. Epub 2021 Jul 30.

UCL Centre for Medical Imaging, Charles Bell House, 43-45 Foley Street, W1W 7TS.

Imaging plays a fundamental role in all aspects of the cancer management pathway. However, conventional imaging techniques are largely reliant on morphological and size descriptors that have well known limitations, particularly when considering targeted-therapy response monitoring. Thus, new imaging methods have been developed to characterise cancer and are now routinely implemented, such as diffusion weighted imaging (DWI), dynamic contrast enhancement (DCE), positron emission technology (PET) and magnetic resonance spectroscopy (MRS). Read More

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Bilateral pleural effusion associated with atezolizumab in a patient with Lynch syndrome-related urothelial carcinoma: a case report.

Ann Palliat Med 2021 Jul 27. Epub 2021 Jul 27.

Division of Hematology and Oncology, Department of Internal Medicine, Jeonbuk National University Hospital-Jeonbuk National University Medical School, Jeonju, Republic of Korea; Research Institute of Clinical Medicine of Jeonbuk National University-Biomedical Research Institute of Jeonbuk National University Hospital, Jeonju, Republic of Korea.

Lynch syndrome (LS) is an inherited syndrome associated with an increased risk of cancer caused by abnormalities in DNA mismatch repair (MMR) genes. Immune checkpoint inhibitors (ICIs) have been reported to lead to a good response in cancers accompanied by LS. However, ICI therapy can cause immune-related adverse events (irAEs). Read More

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