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Journal of Nuclear Cardiology :... Feb 2019Cardiac amyloidosis, once considered untreatable, is now gaining well-deserved attention due to advances in imaging and the recent approval of targeted breakthrough... (Review)
Review
Cardiac amyloidosis, once considered untreatable, is now gaining well-deserved attention due to advances in imaging and the recent approval of targeted breakthrough therapies. In this paper, we discuss the role of radionuclide imaging in the evaluation and management of patients with the most common form of amyloidosis-cardiac transthyretin amyloidosis (ATTR). We provide a comprehensive summary of the literature interspersed with our institutional experience as appropriate, to deliver our perspective.
Topics: Amyloid Neuropathies, Familial; Amyloidosis; Bone and Bones; Cardiomyopathies; Heart; Humans; Prealbumin; Radionuclide Imaging; Technetium Tc 99m Medronate; Technetium Tc 99m Pyrophosphate; Tomography, Emission-Computed, Single-Photon
PubMed: 30569412
DOI: 10.1007/s12350-018-01552-4 -
Seminars in Nuclear Medicine Sep 2014Molecular imaging enables the visualization and interrogation of specific biologic targets and pathways that precede or underlie changes in morphology, physiology, and... (Review)
Review
Molecular imaging enables the visualization and interrogation of specific biologic targets and pathways that precede or underlie changes in morphology, physiology, and function of the heart. Accordingly, it aims at identifying precursors or early stages of cardiac disease, and it may facilitate monitoring and guidance of novel, increasingly specific and versatile cardiovascular therapies. Although SPECT and PET imaging of myocardial metabolism and autonomic innervation are already embedded in clinical practice, various additional targets, probes, and techniques are under development. These techniques hold promise to become a future key in personalizing cardiovascular care.
Topics: Animals; Cell Tracking; Heart; Humans; Inflammation; Radionuclide Imaging; Sympathetic Nervous System; Ventricular Remodeling
PubMed: 25234082
DOI: 10.1053/j.semnuclmed.2014.05.002 -
International Review of Neurobiology 2019Dementia with Lewy bodies (DLB) is the second most common cause of neurodegenerative dementia. The core clinical features of DLB include fluctuating cognition, visual... (Review)
Review
Dementia with Lewy bodies (DLB) is the second most common cause of neurodegenerative dementia. The core clinical features of DLB include fluctuating cognition, visual hallucinations, rapid eye movement sleep behavior disorder, and parkinsonism. Molecular imaging is a powerful tool to assess the brain function in vivo. In this chapter, we reviewed the positron emission tomography, single-photon emission computed tomography, and [I]-metaiodobenzylguanidine scintigraphy studies evaluating the pathological processes underlying DLB, including altered brain metabolism and neurotransmitter pathways, abnormal protein aggregation, and neuroinflammation. These techniques can aid in the differential diagnosis of DLB (versus Alzheimer's disease and related dementia) and in the monitoring disease progression and treatment efficacy of disease-modifying drugs. Furthermore, we explored the limitations of current imaging biomarkers and future directions, particularly focusing on the vital need for tracers that have high affinity for alpha-synuclein.
Topics: Humans; Lewy Body Disease; Molecular Imaging; Neuroimaging; Positron-Emission Tomography; Radionuclide Imaging; Tomography, Emission-Computed, Single-Photon
PubMed: 30638457
DOI: 10.1016/bs.irn.2018.10.007 -
Seminars in Nuclear Medicine Sep 2015To understand pitfalls and limitations in adult renography, it is necessary to understand firstly the physiology of the kidney, especially the magnitude and control of... (Review)
Review
To understand pitfalls and limitations in adult renography, it is necessary to understand firstly the physiology of the kidney, especially the magnitude and control of renal blood flow, glomerular filtration rate and tubular fluid flow rate, and secondly the pharmacokinetics and renal handling of the three most often used tracers, Tc-99m-mercaptoacetyltriglycine (MAG3), Tc-99m-diethylene triamine pentaacetic acid (DTPA) and Tc-99m-dimercaptosuccinic acid (DMSA). The kidneys may be imaged dynamically with Tc-99m-MAG3 or Tc-99m-DTPA, with or without diuretic challenge, or by static imaging with Tc-99m-DMSA. Protocols are different according to whether the kidney is native or transplanted. Quantitative analysis of dynamic data includes measurement of renal vascularity (important for the transplanted kidney), absolute tracer clearance rates, differential renal function (DRF) and response to diuretic challenge. Static image reveals functional renal parenchymal damage, both focal and global, is useful in the clinical management of obstructive uropathy, renal stone disease and hypertension (under angiotensin converting enzyme inhibition), and is the preferred technique for determining DRF. Diagnosis based on morphological appearances is important in transplant management. Even though nuclear medicine is now in the era of hybrid imaging, renal imaging remains an important subspecialty in nuclear medicine and requires a sound basing in applied physiology, the classical supporting discipline of nuclear medicine.
Topics: Adult; Humans; Kidney; Radionuclide Imaging; Radiopharmaceuticals
PubMed: 26278854
DOI: 10.1053/j.semnuclmed.2015.02.008 -
Seminars in Nuclear Medicine Sep 2015The radionuclide (99m)Tc-MDP bone scan is one of the most commonly performed nuclear medicine studies and helps in the diagnosis of different pathologies relating to the... (Review)
Review
The radionuclide (99m)Tc-MDP bone scan is one of the most commonly performed nuclear medicine studies and helps in the diagnosis of different pathologies relating to the musculoskeletal system. With its increasing utility in clinical practice, it becomes more important to be aware of various limitations of this imaging modality to avoid false interpretation. It is necessary to be able to recognize various technical, radiopharmaceutical, and patient-related artifacts that can occur while carrying out a bone scan. Furthermore, several normal variations of tracer uptake may mimic pathology and should be interpreted cautiously. There is an important limitation of a bone scan in metastatic disease evaluation as the inherent mechanism of tracer uptake is not specific for tumor but primarily relies on an osteoblastic response. Thus, it is crucial to keep in mind uptake in benign lesions, which can resemble malignant pathologies. The utility of a planar bone scan in benign orthopedic diseases, especially at sites with complex anatomy, is limited owing to lack of precise anatomical information. SPECT/CT has been significantly helpful in these cases. With wider use of PET/CT and reintroduction of the (18)F-fluoride bone scan, increasing knowledge of potential pitfalls on an (18)F-fluoride bone scan and (18)F-FDG-PET/CT will help in improving the accuracy of clinical reports.
Topics: Animals; Artifacts; Bone Neoplasms; Bone and Bones; Diagnosis, Differential; Humans; Multimodal Imaging; Radionuclide Imaging
PubMed: 26278850
DOI: 10.1053/j.semnuclmed.2015.02.002 -
International Journal of Molecular... Jul 2022The use of molecular imaging technologies for brain imaging can not only play an important supporting role in disease diagnosis and treatment but can also be used to... (Review)
Review
The use of molecular imaging technologies for brain imaging can not only play an important supporting role in disease diagnosis and treatment but can also be used to deeply study brain functions. Recently, with the support of reporter gene technology, optical imaging has achieved a breakthrough in brain function studies at the molecular level. Reporter gene technology based on traditional clinical imaging modalities is also expanding. By benefiting from the deeper imaging depths and wider imaging ranges now possible, these methods have led to breakthroughs in preclinical and clinical research. This article focuses on the applications of magnetic resonance imaging (MRI), single-photon emission computed tomography (SPECT), and positron emission tomography (PET) reporter gene technologies for use in brain imaging. The tracking of cell therapies and gene therapies is the most successful and widely used application of these techniques. Meanwhile, breakthroughs have been achieved in the research and development of reporter genes and their imaging probe pairs with respect to brain function research. This paper introduces the imaging principles and classifications of the reporter gene technologies of these imaging modalities, lists the relevant brain imaging applications, reviews their characteristics, and discusses the opportunities and challenges faced by clinical imaging modalities based on reporter gene technology. The conclusion is provided in the last section.
Topics: Brain; Genes, Reporter; Magnetic Resonance Imaging; Neuroimaging; Positron-Emission Tomography; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed
PubMed: 35955578
DOI: 10.3390/ijms23158443 -
Journal of Nuclear Medicine Technology Mar 2017Epilepsy is one of the most common yet diverse neurologic disorders, affecting almost 1%-2% of the population. Presently, radionuclide imaging such as PET and SPECT is... (Review)
Review
Epilepsy is one of the most common yet diverse neurologic disorders, affecting almost 1%-2% of the population. Presently, radionuclide imaging such as PET and SPECT is not used in the primary diagnosis or evaluation of recent-onset epilepsy. However, it can play a unique and important role in certain specific situations, such as in noninvasive presurgical localization of epileptogenic brain regions in intractable-seizure patients being considered for epilepsy surgery. Radionuclide imaging can be particularly useful if MR imaging is either negative for lesions or shows several lesions of which only 1 or 2 are suspected to be epileptogenic and if electroencephalogram changes are equivocal or discordant with the structural imaging. Similarly, PET and SPECT can also be useful for evaluating the functional integrity of the rest of the brain and may provide useful information on the possible pathogenesis of the neurocognitive and behavioral abnormalities frequently observed in these patients.
Topics: Epilepsy; Humans; Positron-Emission Tomography; Radioactive Tracers; Temporal Lobe; Tomography, Emission-Computed, Single-Photon
PubMed: 28258205
DOI: 10.2967/jnumed.112.114397 -
Current Neurology and Neuroscience... Sep 2018Patients with Parkinson's disease (PD) often display gastrointestinal and genitourinary autonomic symptoms years or even decades prior to diagnosis. These symptoms are... (Review)
Review
PURPOSE OF REVIEW
Patients with Parkinson's disease (PD) often display gastrointestinal and genitourinary autonomic symptoms years or even decades prior to diagnosis. These symptoms are thought to be caused in part by pathological α-synuclein inclusions in the peripheral autonomic and enteric nervous systems. It has been proposed that the initial α-synuclein aggregation may in some PD patients originate in peripheral nerve terminals and then spread centripetally to the spinal cord and brainstem. In vivo imaging methods can directly quantify the degeneration of the autonomic nervous system as well as the functional consequences such as perturbed motility. Here, we review the methodological principles of these imaging techniques and the major findings in patients with PD and atypical parkinsonism.
RECENT FINDINGS
Loss of sympathetic and parasympathetic nerve terminals in PD can be visualized using radiotracer imaging, including I-MIBG scintigraphy, and F-dopamine and C-donepezil PET. Recently, ultrasonographical studies disclosed reduced diameter of the vagal nerves in PD patients. Radiological and radioisotope techniques have demonstrated dysmotility and prolonged transit time throughout all subdivisions of the gastrointestinal tract in PD. The prevalence of objective dysfunction as measured with these imaging methods is often considerably higher compared to the prevalence of subjective symptoms experienced by the patients. Degeneration of the autonomic nervous system may play a key role in the pathogenesis of PD. In vivo imaging techniques provide powerful and noninvasive tools to quantify the degree and extent of this degeneration and its functional consequences.
Topics: Autonomic Nervous System; Humans; Parkinson Disease; Parkinsonian Disorders; Positron-Emission Tomography; Radionuclide Imaging; Tomography, Emission-Computed, Single-Photon
PubMed: 30232650
DOI: 10.1007/s11910-018-0889-4 -
AJR. American Journal of Roentgenology Sep 2023Neuroendocrine neoplasms (NENs) of the small bowel are typically slow-growing lesions that remain asymptomatic until reaching an advanced stage. Imaging modalities for... (Review)
Review
Neuroendocrine neoplasms (NENs) of the small bowel are typically slow-growing lesions that remain asymptomatic until reaching an advanced stage. Imaging modalities for lesion detection, staging, and follow-up in patients with known or suspected NEN include CT enterography, MR enterography, and PET/CT using a somatostatin receptor analog. FDG PET/CT may have a role in the evaluation of poorly differentiated NENs. Liver MRI, ideally with a hepatocyte-specific contrast agent, should be used in the evaluation of hepatic metastases. Imaging informs decisions regarding both surgical approaches and systematic therapy (specifically, peptide receptor radionuclide therapy). This Expert Panel Narrative Review describes the multimodality imaging features of small-bowel NENs; explores the optimal imaging modalities for their diagnosis, staging, and follow-up; and discusses how imaging may be used to guide therapy.
Topics: Humans; Positron Emission Tomography Computed Tomography; Intestinal Neoplasms; Positron-Emission Tomography; Somatostatin; Radionuclide Imaging; Neuroendocrine Tumors
PubMed: 36752369
DOI: 10.2214/AJR.22.28877 -
Frontiers of Hormone Research 2016Neuroendocrine tumors (NETs) comprise a heterogeneous group of malignancies with a very variable clinical expression and progression. They present unique properties that... (Review)
Review
Neuroendocrine tumors (NETs) comprise a heterogeneous group of malignancies with a very variable clinical expression and progression. They present unique properties that are important to consider for radiological and nuclear imaging, such as APUD-characteristics (amine precursor uptake and dearboxylation), as well as the expression of somatostatin receptors. The most common localizations are the lungs, gastrointestinal tract and pancreas. The only curative treatment is surgery, but more than 50% present metastatic disease at the time of diagnosis. The systemic treatment includes chemotherapy and targeted agents, as well as peptide receptor radiotherapy. The diagnosis and follow-up of these tumors necessitate a large number of different imaging methods, such as CT, MRI, US, SRS and PET. Ultrasonography offers the possibility to take guided biopsies from different lesions. Somatostatin receptor scintigraphy was developed in the 1990s and nowadays presents the standard of care for NETs in most countries. The procedure offers a total body examination and a better staging of the disease. However, it has been replaced in most centers by PET/CT with 68Ga-DOTA-somatostatin analogues with a superior spatial resolution and faster imaging (one-stop procedure). Another tracer used for PET/CT is 18FDG, particularly for high-grade tumors. Other more specific tracers are 18F-L-DOPA, 11C-L-DOPA and 11C-5-hydroxytryptophan, which have demonstrated excellent imaging results. The new targeted agents present a challenge in the evaluation procedure of treatment and, therefore, new imaging techniques and an improvement of currently available techniques are mandatory.
Topics: Humans; Magnetic Resonance Imaging; Neuroendocrine Tumors; Positron Emission Tomography Computed Tomography; Radionuclide Imaging; Ultrasonography
PubMed: 27002535
DOI: 10.1159/000442331