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Although molecular imaging has had a dramatic impact on diagnostic imaging, it has only recently begun to be integrated into interventional procedures. Its significant impact is attributed to its ability to provide noninvasive, physiologic information that supplements conventional morphologic imaging. The four major interventional opportunities for molecular imaging are, first, to provide guidance to localize a target; second, to provide tissue analysis to confirm that the target has been reached; third, to provide in-room, posttherapy assessment; and fourth, to deliver targeted therapeutics. With improved understanding and application of(18)F-FDG, as well as the addition of new molecular probes beyond(18)F-FDG, the future holds significant promise for the expansion of molecular imaging into the realm of interventional procedures., (© 2016 by the Society of Nuclear Medicine and Molecular Imaging, Inc.)

Nuclear cardiology imaging tests are widely performed in Japan as clinical practice. The Japanese nuclear cardiology community has developed new diagnostic imaging tests using (123)I-beta-methyl-p-iodophenyl-pentadecanoic acid, (123)I-metaiodobenzylguanidine, and (18)F-fluorodeoxyglucose PET for detecting cardiac involvement in sarcoidosis. These tests have become popular worldwide. The Japanese Circulation Society and the Japanese Society of Nuclear Cardiology have published clinical imaging guidelines showing indications and standards for the new imaging tests. JSNC is currently striving to improve the standard of clinical practice and is promoting research activities.

In recent years there has been methodological improvement in established nuclear medicine procedures, such as renal and skeletal scintigraphy and new very specific probes for treatment and diagnosis of urological diseases have been introduced into the clinical routine. New diagnostic methods, such as positron emission tomography (PET) using prostate-specific membrane antigen (PSMA) ligands for highly accurate tumor localization in recurrent prostate cancer have become available in many centers. The very high and selective accumulation of these PSMA ligands in tumor tissue has shown promising therapeutic results. Moreover, since 2013 a new radiopharmaceutical agent, radium-223 dichloride, has been approved for treatment of symptomatic bone metastases of prostate cancer. Better knowledge of indications, benefits and limitations of these procedures will help clinicians to adequately introduce them into patient management. This article summarizes the state of the art in established nuclear medicine procedures for urological disorders and also reports on new diagnostic and therapeutic possibilities.

Nuclear medicine imaging provides valuable functional information that complements information obtained with anatomic imaging techniques in the evaluation of patients with specific acute clinical manifestations. Nuclear medicine studies are most often used in conjunction with other imaging modalities and as a problem-solving tool. Under certain circumstances a nuclear medicine study may be indicated as the first-line imaging modality, as in the case of renal scintigraphy for transplant dysfunction in the early postoperative period. Nuclear imaging may be preferred when a conventional first-line study is contraindicated or when it is important to minimize radiation exposure. The portability of nuclear imaging offers particular advantages for the evaluation of critically ill patients whose clinical condition is unstable and who cannot be safely transported out of the intensive care unit. The ability to visualize physiologic and pathophysiologic processes over relatively long time periods without adding to the patient's radiation exposure contributes to the high diagnostic sensitivity of several types of nuclear medicine studies. Viewing the acquired images in the cine mode adds to the value of these studies for diagnosing and characterizing dynamic abnormalities such as intermittent internal bleeding and bile or urine leakage. In this pictorial review, the spectrum of nuclear medicine studies commonly performed in the acute care setting is reviewed according to body systems and organs, with detailed descriptions of the indications, technical considerations, findings, and potential pitfalls of each type of study. Supplemental material available at http://radiographics.rsna.org/lookup/suppl/doi:10.1148/rg.332125098/-/DC1.

Molecular imaging is a new and evolving field that employs a targeted approach to noninvasively assess biologic processes in vivo. By assessing key elements in specific cellular processes prior to irreversible end-organ damage, molecular tools will allow for earlier detection and intervention, improving management and outcomes associated with cardiovascular diseases. The goal of those working to expand this field is not just to provide diagnostic and prognostic information, but rather to guide an individual's pharmacological, cell-based, or genetic therapeutic regimen. This article will review molecular imaging tools in the context of our current understanding of biological processes of the myocardium, including angiogenesis, ventricular remodeling, inflammation, and apoptosis. The focus will be on radiotracer-based molecular imaging modalities with an emphasis on clinical application. Though this field is still in its infancy and may not be fully ready for widespread use, molecular imaging of myocardial biology has begun to show promise of clinical utility in acute and chronic ischemia, acute myocardial infarction, congestive heart failure, as well as in more global inflammatory and immune-mediated responses in the heart-like myocarditis and allogeneic cardiac transplant rejection. With continued research and development, molecular imaging promises to be an important tool for the optimization of cardiovascular care.

The successful management of prostate cancer requires early detection, appropriate risk assessment, and optimum treatment. An unmet goal of prostate cancer imaging is to differentiate indolent from aggressive tumors, as treatment may vary for different grades of the disease. Different modalities have been tested to diagnose, stage, and monitor prostate cancer during therapy. This review briefly describes the key clinical issues in prostate cancer imaging and therapy and summarizes the various new imaging modalities and agents in use and on the horizon.

A promising role of cellular therapies in cancer treatment is reflected by the constantly growing number of clinical trials with adoptively transferred cells. Direct and indirect cell labeling for the nuclear imaging of transferred cells has been proven reliable for imaging adoptive cellular therapies. Both methods show their advantages and limitations. Direct labeling is a relatively easy, inexpensive, and well-established methodology. Indirect labeling using a reporter gene imaging paradigm allows for reliable, stable, and harmless visualization of cellular trafficking, persistence, proliferation, and function at the target site. It is expected that new human-derived reporter genes will be rapidly translated into clinical applications that require repetitive imaging for the effective monitoring of various genetic and cellular therapies.

The objective of cardiac stress testing is to detect coronary artery disease (CAD) and to prevent future adverse events, such as myocardial infarction or death. The progression from electrocardiographically based stress testing to current SPECT and PET technologies has brought improvements in diagnostic efficacy and resolution. Myocardial perfusion imaging facilitates management of CAD in elective and acute settings by providing valuable diagnostic and prognostic information. Hybrid PET/CT and SPECT/CT systems impart complementary information of coronary anatomy and its physiologic significance on blood flow reserve. In the current era, diagnosis and treatment of cardiovascular disease is increasingly defined by underlying molecular and genomic aberrations rather than by clinical signs and symptoms alone. Nuclear imaging is uniquely primed to exploit the targeting of expressed cell-surface molecules and intracellular processes of cardiovascular disease and to foster the development of innovative therapeutic interventions in the future.

Echocardiography, magnetic resonance imaging and, more recently, multidetector computed tomography, have led to major advances in noninvasive image assessment of anatomy in pediatric cardiology. The radionuclide methods often lack sufficient resolution to precisely characterize complex morphology in congenital heart lesions. However, these methods provide an accurate and reproduceable quantitative assessment of the physiological consequences of structural heart disease. These unique capabilities will continue to assure ongoing clinical relevance of radionuclide methodology, as is the case in the assessment of heart disease in adult cardiology.

Unlabelled: The Subcommittee on Survey of Nuclear Medicine Practice in Japan has performed a nationwide survey of nuclear medicine practice every five years since 1982 to provide detailed information on its current status., Methods: Questionnaires were sent to every institution known to the Japan Radioisotope Association to provide nuclear medicine examinations. The questionnaires address the number and kind of nuclear medicine examinations performed as well as the kind and dose of the radiopharmaceuticals used during the month of June 2002. The annual number of total or specific examinations was then estimated., Results: Of the institutions sent questionnaires, 1,204 were for in vivo study, 124 were for in vitro study, and 36 were for positron emission tomography (PET) study. Out of these, 95.8% answered them. A total of 1,697 gamma cameras were installed in 1,160 facilities, of which 50% were dual-head cameras. The estimated total annual number of examinations expressed by the number of administered radiopharmaceuticals was 1.60 million, similar to that of the previous survey (1997). The frequency of study with single photon emission computed tomography (SPECT) increased to 40%, from 30% in the previous survey. The scintigraphy most frequently performed was bone (35%), followed by myocardium (24%) and brain perfusion (12%). All showed a continuous increase over the past 20 years. Tumor imaging, however, fell from third to fourth place. The most commonly used radiopharmaceutical for each scintigraphy was 99mTc-HMDP for bone, 201Tl-chloride for myocardium, 67Ga-citrate for tumor, and 123I-IMP for brain. A total of 29,376 PET studies were performed yearly. Among them, 18F-FDG rapidly increased 3.7-fold. 131I therapy for thyroid cancer and hyperthyroidism was conducted yearly in 1,647 and 3,347 patients, respectively. A total of 31.35 million in vitro radioassays were carried out yearly, the number of which has been decreasing continuously since 1992., Conclusions: It was proved that the content of nuclear medicine practice in Japan has changed in the past five years. This report might be useful for understanding the current trends of nuclear medicine practice in Japan.

This review article forecasts developments in nuclear medicine instrumentation which are on the horizon. Special attention is paid to the physical properties of detectors and multiple-processor parallel processing systems needed for fast and high-quality imaging in emission tomography. Advances in detector technology will improve imaging resolution below 5 mm and will increase sensitivity and quantitative accuracy. In addition, high count rate list-mode acquisition enables 'true' four-dimensional data-sets. A sandwich-like construction of two different crystals allows the simultaneous use of conventional tracers and positron tracers (multiple emission tomography, MET). Transmission-based attenuation and scatter compensation with fast iterative reconstruction methods will further improve image quality. The clinical and scientific importance of improved images and the limits on advances in instrumentation are also reviewed.

Over the past 2 decades we have witnessed an explosion of new radioisotopic tracers aimed at detecting, staging and eventually treating tumors. In fact, nuclear oncology has evolved into a field on its own. Aside from aspecific radioisotopic tracers such as thallium 201 or gallium 67, clinicians and oncologists can now use specific radiolabeled monoclonal antibodies and metabolic tracers. In the near future, molecular probes based on the sequencing of the human genome with an exquisite specificity should also become available. In this article, we shall review the most recent developments in this new field.

The use of radionuclides for medical and for a multitude of other basic research applications has continued to grow at a very rapid pace. Procedures, based on their use as radiotracers for nuclear medicine imaging and for radiotherapy of cancer and other pathology, have become firmly established as important clinical modalities. It is estimated that on an annual basis in the United States alone, radionuclides are used medically in over 13 million imaging procedures, in over 100 million laboratory tests, and in an ever increasing number (> 100,000) for therapeutic administrations. One out of every four hospital patients undergoes a procedure that involves the use of radionuclides. Diagnostic imaging methods using planar/single-photon emission computed tomography and positron-emission tomography (PET) imaging, as well as the measurement of in vivo organ function, physiology, or biochemistry, have become indispensable tools in patient workup and management. More than 80% of all imaging studies (mostly anatomic) currently use technetium-99m (99mTc), because it has turned out to be the ideal isotope from various considerations. However, over the past few years, nuclear medicine has experienced a slow but steady evolution towards functional studies, quantitative PET imaging, and novel therapeutic approaches. New radionuclides are required for these applications, and their development has attracted considerable interest. This article reviews the current status and future prospects for the development of many new potential isotopes. Practical issues, such as the feasibility of large-scale production and wide-spread availability in a continuous reliable fashion, are addressed. To date, the data are not sufficient to answer the question as to whether any of these radionuclides (or their applications, for that matter) will eventually assume as broad-based a role as that of 99mTc. Nonetheless, there are a number of promising radionuclides that could assume an important place in the future practice of nuclear medicine.