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Journal of Nuclear Medicine : Official... Feb 2014Molecular imaging is a multimodality discipline for noninvasively visualizing biologic processes at the subcellular level. Clinical applications of radionuclide-based... (Review)
Review
Molecular imaging is a multimodality discipline for noninvasively visualizing biologic processes at the subcellular level. Clinical applications of radionuclide-based molecular imaging for breast cancer continue to evolve. Whole-body imaging, with scintimammography and PET, and newer dedicated breast imaging systems are reviewed. The potential clinical indications and the challenges of implementing these emerging technologies are presented.
Topics: Breast Neoplasms; Clinical Trials as Topic; Female; Gamma Cameras; Humans; Mammography; Multimodal Imaging; Positron-Emission Tomography; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Tomography, X-Ray Computed; Whole Body Imaging
PubMed: 24434288
DOI: 10.2967/jnumed.113.126102 -
Indian Journal of Nuclear Medicine :... Nov 2018Evidence-based historical accounts of critical events, which shaped nuclear medicine in India today, are presented in this article. There was parallel activity happening... (Review)
Review
Evidence-based historical accounts of critical events, which shaped nuclear medicine in India today, are presented in this article. There was parallel activity happening in the northern and western region of India in the early 60s. Radiation Medicine Center (RMC) at Mumbai inaugurated in September 1963 by Dr. Bhabha; and Institute of Nuclear Medicine and Allied Sciences, Delhi dedicated to the nation in February 1964. The isotope division of Bhabha Atomic Research Center endured as the backbone in the supply of indigenously produced medical radioisotopes in research reactors APSARA (1958) and CIRUS (1960). Design and dispatch of economical generators (loaded with low specific activity Mo) with indigenously designed solvent extraction (Methyl Ethyl Ketone) technique had led to rapid growth of nuclear medicine facilities in the country. As per recently released list (July 2018) of the Atomic Energy Regulatory Board, there are 293 nuclear medicine departments in the country. Of which 14% are in the government sector, and the remaining 86% are under private ownership. There are currently 233 functioning gamma cameras (Single-photon emission computed tomography [SPECT]/SPECT-computed tomography [CT]) units in India since 1969 when the first gamma camera was commissioned at RMC. The first medical cyclotron (2002) and first positron emission tomography (PET) (2002) and first PET-CT (2004) in Mumbai had triggered revolution of molecular imaging in India. There are 222 PET-CT, 3 PET-magnetic resonance imaging scanners, and 19 cyclotrons operating currently. India has witnessed relatively slower headways in terms of high dose radionuclide therapy facilities. After first indoor facility at RMC in 1964, only 92 radionuclide therapy (isolation) wards have come up with no more than 200 beds for the entire country in the last 54 years. India started Delhi university approved structured postgraduate diploma in nuclear medicine in 1963 at the Institute of Nuclear Medicine and Allied Sciences (INMAS), first of its kind course in the world at that time. RMC started Mumbai University recognized diploma courses for physicians (Diploma in Radiation Medicine) and technologists (Diploma in Medical Radioisotope Techniques) in 1973. National Board of Examination (Government of India) recognized nuclear medicine as a broad specialty in 1982 and accredited RMC for training for Diplomate of National Board. Doctor of Medicine (MD) started first time in India and Asia at Sanjay Gandhi Postgraduate Institute, Lucknow in 1990. Doctorate of Therapeutic Nuclear Medicine commenced at All India Institute of Medical Sciences Delhi in 2015. There are 18 teaching hospitals currently imparting MD/DNB nuclear medicine residency for physicians with annual intake of 50. Eighteen institutions are offering bachelors and masters programs for nuclear medicine technology with an average annual intake of 110-120 students. Society of Nuclear Medicine, India (SNMI) is the oldest and largest professional body with total life membership of 1425 nuclear medicine professionals. SNMI was established in 1967 and hosted the first Annual Conference at RMC, Mumbai in 1968. Since then, SNMI is organizing its Annual Conferences in various parts of the country with the objective of scientific exchange and popularizing the modality amongst clinicians. Postgraduate Institute of Medical Education Research is hosting the 50 Annual Conference of SNMI (SNMICON-18) as mark of golden jubilee celebration.
PubMed: 30533977
DOI: 10.4103/0972-3919.245053 -
Seminars in Nuclear Medicine Jan 2011Radionuclide imaging of the kidneys with gamma cameras involves the use of labeled molecules seeking functionally critical molecular mechanisms to detect the... (Review)
Review
Radionuclide imaging of the kidneys with gamma cameras involves the use of labeled molecules seeking functionally critical molecular mechanisms to detect the pathophysiology of the diseased kidneys and achieve an early, sensitive, and accurate diagnosis. The most recent imaging technology, positron emission tomography, permits quantitative imaging of the kidney at a spatial resolution appropriate for the organ. H(2)(15)O, (82)RbCl, and [(64)Cu] ETS are the most important radiopharmaceuticals for measuring renal blood flow. The renin angiotensin system is the most important regulator of renal blood flow; this role is being interrogated by detecting angiotensin receptor subtype angiotensin subtype 1 receptor by the use of in vivo positron emission tomography. Membrane organic anion transporters are important for the function of the tubular epithelium; therefore, Tc99m MAG3 as well as some novel radiopharmaceuticals, such as copper-64 labeled mono oxo-tetraazamacrocyclic ligands, have been used for molecular renal imaging. In addition, other radioligands that interact with the organic cation transporters or peptide transporters have been developed. Focusing on early detection of kidney injury at the molecular level is an evolving field of great significance. Potential imaging targets are the kidney injury molecule 1, which is highly expressed in kidney injury and renal cancer but not in normal kidneys. Although pelvic clearance, in addition to parenchymal transport, is an important measure in obstructive nephropathy, techniques that focus on up-regulated molecules in response to tissue stress resulting from obstruction will be of great implication. Monocyte chemoattractant protein-1 is a well-suited molecule here. The greatest advances in molecular imaging of the kidneys have been recently achieved in detecting renal cancer. In addition to the ubiquitous [(18)F] fluorodeoxyglucose, other radioligands, such as [(11)C] acetate and anti-1-amino-3-[18F]fluorocyclobutane-1-carboxylic acid, have emerged. Radioimmunoimaging with [(124)I] G250 could lead to radioimmunotherapy for renal cancer. Considering the increasing age of general population, the incidence of kidney diseases, such as atherosclerosis, diabetic nephropathy, and cancer, is expected to increase. Successful management of these diseases offers an opportunity and a challenge for development of novel molecular imaging technologies.
Topics: Animals; Humans; Kidney; Kidney Neoplasms; Kidney Tubules; Molecular Imaging; Radionuclide Imaging; Regional Blood Flow
PubMed: 21111857
DOI: 10.1053/j.semnuclmed.2010.09.003 -
Physics in Medicine and Biology May 2021Built on top of the Geant4 toolkit, GATE is collaboratively developed for more than 15 years to design Monte Carlo simulations of nuclear-based imaging systems. It is,... (Review)
Review
Built on top of the Geant4 toolkit, GATE is collaboratively developed for more than 15 years to design Monte Carlo simulations of nuclear-based imaging systems. It is, in particular, used by researchers and industrials to design, optimize, understand and create innovative emission tomography systems. In this paper, we reviewed the recent developments that have been proposed to simulate modern detectors and provide a comprehensive report on imaging systems that have been simulated and evaluated in GATE. Additionally, some methodological developments that are not specific for imaging but that can improve detector modeling and provide computation time gains, such as Variance Reduction Techniques and Artificial Intelligence integration, are described and discussed.
Topics: Artificial Intelligence; Computer Simulation; Monte Carlo Method; Software; Tomography, X-Ray Computed
PubMed: 33770774
DOI: 10.1088/1361-6560/abf276 -
The British Journal of Radiology Dec 2011During the last two decades, radionuclide myocardial perfusion scintigraphy (MPS) has become established as the main functional cardiac imaging technique for the... (Review)
Review
During the last two decades, radionuclide myocardial perfusion scintigraphy (MPS) has become established as the main functional cardiac imaging technique for the assessment of ischaemic heart disease (IHD). Despite a growing number of alternative functional imaging techniques, MPS still remains the most widely used technique, with a wealth of literature supporting its usefulness in assessing IHD and predicting prognosis. The technique itself has evolved, making it more reliable and robust, with additional ventricular functional information that further defines the prognosis in these patients. With the advent of hybrid single photon emission with CT and positron emission tomography with CT cameras together with the development of new camera technology that enables faster images with less radiation and better resolution, MPS will remain an essential part of IHD investigation. There are new promising radiopharmacological developments and applications such as radiolabelled fatty acids and meta-iodobenzylguanidine. These will widen the scope of nuclear medicine imaging to include patients with cardiac failure and acute chest pain presenting to accident and emergency departments. Nuclear medicine cardiac investigations will continue to have an essential role in the diagnosis, stratification and prognosis of patients with cardiac disease, complementing the new developing cardiac modalities such as CT coronary angiography and MRI.
Topics: Coronary Artery Disease; Humans; Image Processing, Computer-Assisted; Multimodal Imaging; Myocardial Ischemia; Myocardial Perfusion Imaging; Nuclear Medicine; Positron-Emission Tomography; Prognosis; Radiopharmaceuticals; Software; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed
PubMed: 22723530
DOI: 10.1259/bjr/14625142 -
Scientific Reports Feb 2022For radiological diagnosis and radionuclide therapy, X-ray and gamma-ray imaging technologies are essential. Single-photon emission tomography (SPECT) and positron...
For radiological diagnosis and radionuclide therapy, X-ray and gamma-ray imaging technologies are essential. Single-photon emission tomography (SPECT) and positron emission tomography (PET) play essential roles in radiological diagnosis, such as the early detection of tumors. Radionuclide therapy is also rapidly developing with the use of these modalities. Nevertheless, a limited number of radioactive tracers are imaged owing to the limitations of the imaging devices. In a previous study, we developed a hybrid Compton camera that conducts simultaneous Compton and pinhole imaging within a single system. In this study, we developed a system that simultaneously realizes three modalities: Compton, pinhole, and PET imaging in 3D space using multiple hybrid Compton cameras. We achieved the simultaneous imaging of Cs-137 (Compton mode targeting 662 keV), Na-22 (PET mode targeting 511 keV), and Am-241 (pinhole mode targeting 60 keV) within the same field of view. In addition, the imaging of Ga-67 and In-111, which are used in various diagnostic scenarios, was conducted. We also verified that the 3D distribution of the At-211 tracer inside a mouse could be imaged using the pinhole mode.
PubMed: 35169183
DOI: 10.1038/s41598-022-06401-6 -
The Quarterly Journal of Nuclear... Mar 2006Positron emission tomography (PET) is an investigative tool that has allowed unprecedented in vivo quantification of physiologic processes including myocardial perfusion... (Review)
Review
Positron emission tomography (PET) is an investigative tool that has allowed unprecedented in vivo quantification of physiologic processes including myocardial perfusion and metabolism. Several technical features make PET an ideal technology for the noninvasive evaluation of cardiac physiology. The exponential growth in the number of PET cameras worldwide, offers new opportunities for cardiac applications of PET. Moreover, the integration of PET and multidetector CT (PET/CT) technology will likely accelerate the clinical use of this modality in cardiology for revealing the degree and location of anatomic stenoses and their physiologic significance, the atherosclerotic plaque burden and its composition. Integrated PET/CT is a powerful noninvasive modality to establish the diagnosis, define risk, and guide management with a single study of CAD patients.
Topics: Coronary Artery Disease; Humans; Positron-Emission Tomography; Practice Patterns, Physicians'; Subtraction Technique; Systems Integration; Tomography, X-Ray Computed
PubMed: 16557203
DOI: No ID Found -
NeuroImage May 2023Super-resolution (SR) is a methodology that seeks to improve image resolution by exploiting the increased spatial sampling information obtained from multiple...
Super-resolution (SR) is a methodology that seeks to improve image resolution by exploiting the increased spatial sampling information obtained from multiple acquisitions of the same target with accurately known sub-resolution shifts. This work aims to develop and evaluate an SR estimation framework for brain positron emission tomography (PET), taking advantage of a high-resolution infra-red tracking camera to measure shifts precisely and continuously. Moving phantoms and non-human primate (NHP) experiments were performed on a GE Discovery MI PET/CT scanner (GE Healthcare) using an NDI Polaris Vega (Northern Digital Inc), an external optical motion tracking device. To enable SR, a robust temporal and spatial calibration of the two devices was developed as well as a list-mode Ordered Subset Expectation Maximization PET reconstruction algorithm, incorporating the high-resolution tracking data from the Polaris Vega to correct motion for measured line of responses on an event-by-event basis. For both phantoms and NHP studies, the SR reconstruction method yielded PET images with visibly increased spatial resolution compared to standard static acquisitions, allowing improved visualization of small structures. Quantitative analysis in terms of SSIM, CNR and line profiles were conducted and validated our observations. The results demonstrate that SR can be achieved in brain PET by measuring target motion in real-time using a high-resolution infrared tracking camera.
Topics: Animals; Positron Emission Tomography Computed Tomography; Motion Capture; Positron-Emission Tomography; Motion; Brain; Phantoms, Imaging; Algorithms; Image Processing, Computer-Assisted
PubMed: 36977452
DOI: 10.1016/j.neuroimage.2023.120056 -
Scientific Reports Nov 2020Optical imaging of particle beams is a promising method for range and width estimations. However it was not clear that optical imaging was possible for muons. To clarify...
Optical imaging of particle beams is a promising method for range and width estimations. However it was not clear that optical imaging was possible for muons. To clarify this, we conducted optical imaging of muons, since high-intensity muons are now available at J-PARC. We irradiated positive muons with different momenta to water or plastic scintillator block, and imaged using a charge-coupled device (CCD) camera during irradiation. The water and plastic scintillator block produced quite different images. The images of water during irradiation of muons produced elliptical shape light distribution at the end of the ranges due to Cherenkov-light from the positrons produced by positive muon decay, while, for the plastic scintillator block, we measured images similar to the dose distributions. We were able to estimate the ranges of muons as well as the measurement of the asymmetry of the direction of the positron emission by the muon decays from the optical images of the water, although the measured ranges were 4 mm to 5 mm larger than the calculated values. The ranges and widths of the beams could also be estimated from the optical images of the plastic scintillator block. We confirmed that optical imaging of muons was possible and is a promising method for the quality assessment, research of muons, and the future muon radiotherapy.
PubMed: 33244067
DOI: 10.1038/s41598-020-76652-8 -
AJNR. American Journal of Neuroradiology Aug 2008The basic principles of scintigraphy are reviewed and extended to 3D imaging. Single-photon emission computed tomography (SPECT) is a sensitive and specific 3D technique... (Comparative Study)
Comparative Study Review
The basic principles of scintigraphy are reviewed and extended to 3D imaging. Single-photon emission computed tomography (SPECT) is a sensitive and specific 3D technique to monitor in vivo functional processes in both clinical and preclinical studies. SPECT/CT systems are becoming increasingly common and can provide accurately registered anatomic information as well. In general, SPECT is affected by low photon-collection efficiency, but in brain imaging, not all of the large FOV of clinical gamma cameras is needed: The use of fan- and cone-beam collimation trades off the unused FOV for increased sensitivity and resolution. The design of dedicated cameras aims at increased angular coverage and resolution by minimizing the distance from the patient. The corrections needed for quantitative imaging are challenging but can take advantage of the relative spatial uniformity of attenuation and scatter. Preclinical systems can provide submillimeter resolution in small animal brain imaging with workable sensitivity.
Topics: Algorithms; Equipment Design; Humans; Image Processing, Computer-Assisted; Imaging, Three-Dimensional; Mathematics; Nuclear Physics; Positron-Emission Tomography; Radioisotopes; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed
PubMed: 18583408
DOI: 10.3174/ajnr.A1175