Positron emission tomography (PET) is a functional imaging technique that uses radioactive substances known as radiotracers to visualize and measure changes in metabolic processes, and in other physiological activities including blood flow, regional chemical composition, and absorption. Different tracers are used for various imaging purposes, depending on the target process within the body. For example, 18
F
-FDG is commonly used to detect cancer, NaF18
F
is widely used for detecting bone formation, and oxygen-15 is sometimes used to measure blood flow.
Radionuclide therapy uses radioactive substances called radiopharmaceuticals to treat medical conditions, particularly cancer. These are introduced into the body by various means and localise to specific locations, organs or tissues depending on their properties and administration routes. This includes anything from a simple compound such as sodium iodide that locates to the thyroid via trapping the iodide ion, to complex biopharmaceuticals such as recombinant antibodies which are attached to radionuclides and seek out specific antigens on cell surfaces.
Nuclear medicine or nucleology is a medical specialty involving the application of radioactive substances in the diagnosis and treatment of disease. Nuclear imaging, in a sense, is "radiology done inside out" because it records radiation emitting from within the body rather than radiation that is generated by external sources like X-rays. In addition, nuclear medicine scans differ from radiology, as the emphasis is not on imaging anatomy, but on the function. For such reason, it is called a physiological imaging modality. Single photon emission computed tomography (SPECT) and positron emission tomography (PET) scans are the two most common imaging modalities in nuclear medicine.
[18F]Fluorodeoxyglucose (INN), or fluorodeoxyglucose F 18, also commonly called fluorodeoxyglucose and abbreviated [18F]FDG, 2-[18F]FDG or FDG, is a radiopharmaceutical, specifically a radiotracer, used in the medical imaging modality positron emission tomography (PET). Chemically, it is 2-deoxy-2-[18F]fluoro-D-glucose, a glucose analog, with the positron-emitting radionuclide fluorine-18 substituted for the normal hydroxyl group at the C-2 position in the glucose molecule.
A gallium scan is a type of nuclear medicine test that uses either a gallium-67 (67Ga) or gallium-68 (68Ga) radiopharmaceutical to obtain images of a specific type of tissue, or disease state of tissue. Gallium salts like gallium citrate and gallium nitrate may be used. The form of salt is not important, since it is the freely dissolved gallium ion Ga3+ which is active. Both 67Ga and 68Ga salts have similar uptake mechanisms. Gallium can also be used in other forms, for example 68Ga-PSMA is used for cancer imaging. The gamma emission of gallium-67 is imaged by a gamma camera, while the positron emission of gallium-68 is imaged by positron emission tomography (PET).
EF5 is a nitroimidazole derivative used in oncology research. Due to its similarity in chemical structure to etanidazole, EF5 binds in cells displaying hypoxia.
Abass Alavi is an Iranian-American physician-scientist specializing in the field of molecular imaging, most notably in the imaging modality of positron emission tomography (PET). In August 1976, he was part of the team that performed the first human PET studies of the brain and whole body using the radiotracer [18F]Fluorodeoxyglucose (FDG). Alavi holds the position of Professor of Radiology and Neurology, as well as Director of Research Education in the Department of Radiology at the University of Pennsylvania. Over a career spanning five decades, he has amassed over 2,300 publications and 60,000 citations, earning an h-index of 125 and placing his publication record in the top percentile of scientists.
Iobenguane, or MIBG, is an aralkylguanidine analog of the adrenergic neurotransmitter norepinephrine (noradrenaline), typically used as a radiopharmaceutical. It acts as a blocking agent for adrenergic neurons. When radiolabeled, it can be used in nuclear medicinal diagnostic and therapy techniques as well as in neuroendocrine chemotherapy treatments.
Nuclear medicine physicians, also called nuclear radiologists or simply nucleologists, are medical specialists that use tracers, usually radiopharmaceuticals, for diagnosis and therapy. Nuclear medicine procedures are the major clinical applications of molecular imaging and molecular therapy. In the United States, nuclear medicine physicians are certified by the American Board of Nuclear Medicine and the American Osteopathic Board of Nuclear Medicine.
DOTA-TATE is an eight amino acid long peptide, with a covalently bonded DOTA bifunctional chelator.
Positron emission tomography–magnetic resonance imaging (PET–MRI) is a hybrid imaging technology that incorporates magnetic resonance imaging (MRI) soft tissue morphological imaging and positron emission tomography (PET) functional imaging.
Metomidate is a non-barbiturate imidazole that was discovered by Janssen Pharmaceutica in 1965 and under the names is sold as a sedative-hypnotic drug used in Europe to treat humans and for veterinary purposes.
Positron emission mammography (PEM) is a nuclear medicine imaging modality used to detect or characterise breast cancer. Mammography typically refers to x-ray imaging of the breast, while PEM uses an injected positron emitting isotope and a dedicated scanner to locate breast tumors. Scintimammography is another nuclear medicine breast imaging technique, however it is performed using a gamma camera. Breasts can be imaged on standard whole-body PET scanners, however dedicated PEM scanners offer advantages including improved resolution.
The European Association of Nuclear Medicine (EANM) is the leading professional organisation for nuclear medicine in Europe. Established in 1985, the EANM serves as an umbrella organisation comprising national societies, affiliated societies and individual members working in nuclear medicine or related fields. It is also dedicated to the promotion of nuclear medicine amongst international organisations like the International Atomic Energy Agency, EU institutions like the European Union and the general public.
In the field of medicine, radiomics is a method that extracts a large number of features from medical images using data-characterisation algorithms. These features, termed radiomic features, have the potential to uncover tumoral patterns and characteristics that fail to be appreciated by the naked eye. The hypothesis of radiomics is that the distinctive imaging features between disease forms may be useful for predicting prognosis and therapeutic response for various cancer types, thus providing valuable information for personalized therapy. Radiomics emerged from the medical fields of radiology and oncology and is the most advanced in applications within these fields. However, the technique can be applied to any medical study where a pathological process can be imaged.
Siroos Mirzaei is an Iranian specialist in Nuclear Medicine. He is Head of the Department of Nuclear Medicine of the Wilhelminen Hospital in Vienna. Mirzaei is well known for his scientific work on torture diagnostics with molecular imaging methods.
Andreas Kjær is a Danish physician-scientist and European Research Council (ERC) advanced grantee. He is professor at the University of Copenhagen and chief physician at Rigshospitalet, the National University Hospital of Denmark. He is board certified in Nuclear Medicine and his research is focused on molecular imaging with PET and PET/MRI and targeted radionuclide therapies (theranostics) in cancer. His achievements include development of several new PET tracers that have reached first-in-human clinical use. He has published more than 400 peer-review articles, filed 10 patents, supervised more than 40 PhD students and received numerous prestigious scientific awards over the years. He is a member of the Danish Academy of Technical Sciences
Peptide receptor radionuclide therapy (PRRT) is a type of radionuclide therapy, using a radiopharmaceutical that targets peptide receptors to deliver localised treatment, typically for neuroendocrine tumours (NETs).
Jason S. Lewis is a British radiochemist whose work relates to oncologic therapy and diagnosis. His research focus is a molecular imaging-based program focused on radiopharmaceutical development as well as the study of multimodality small- and biomolecule-based agents and their clinical translation. He has worked on the development of small molecules as well as radiolabeled peptides and antibodies probing the overexpression of receptors and antigens on tumors.
Theranostics, also known as theragnostics, is an emerging field in precision medicine that combines diagnostic and therapeutic approaches to provide the potential for personalized treatment and real-time monitoring of the effectiveness of treatments. Improvements in imaging techniques and targeted therapies are the basis of the field of theranostics. For some conditions, medical imaging has enabled non-invasive visualization of disease processes, identification of specific molecular targets, and monitoring treatment response. When medical imaging is coupled with the development of novel radiotracers and contrast agents, theranostics may provide opportunities for precise diagnosis and targeted therapy.
