Search

Proton sound detectors rely on sensing the weak thermoacoustic signals emitted by the fast energy deposition at the end of the beam penetration path through the energy absorber. The energy of the ions/protons is first converted into heat, and then, into pressure by a thermodynamic process. The pressure signal propagates through the energy absorber, and it is read by an acoustic sensor, which, in turn, converts the pressure wave into an analog electrical voltage. Such an analog signal is digitalized by the analog front-end. Its digital representation is used for the measurement of the beam depth. This emerging technique attracts attention in both physics experiments and medical applications (hadron therapy). This article investigates the signal-to-noise-ratio performance in proton sound detectors exploring all critical steps that lead to both reduction of the power of the electrical signal and noise power increasing. Nonetheless, this article proposes specific technical solutions to mitigate such signal-to-noise-ratio degradations with particular attention to higher energy (i.e., 200 MeV) proton beams, which are crucial for medical applications, and where the maximum achievable signal-to-noise ratio can be 50/60 dB lower than 20 MeV acoustic pulses.

Myocardial fibrosis, seen in ischemic and nonischemic cardiomyopathies, is associated with adverse cardiac outcomes. Noninvasive imaging plays a key role in early identification and quantification of myocardial fibrosis with the use of an expanding array of techniques including cardiac magnetic resonance, computed tomography, and nuclear imaging. This review discusses currently available noninvasive imaging techniques, provides insights into their strengths and limitations, and examines novel developments that will affect the future of noninvasive imaging of myocardial fibrosis.

Cardiac sarcoidosis (CS) is an inflammatory disease with high morbidity and mortality, with a pathognomonic feature of non-caseating granulomatous inflammation. While 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) is a well-established modality to image inflammation and diagnose CS, there are limitations to its specificity and reproducibility. Imaging focused on the molecular processes of inflammation including the receptors and cellular microenvironments present in sarcoid granulomas provides opportunities to improve upon FDG-PET imaging for CS. This review will highlight the current limitations of FDG-PET imaging for CS while discussing emerging new nuclear imaging molecular targets for the imaging of cardiac sarcoidosis.

To investigate the differences in small cell lung cancer (SCLC) diagnostic imaging utilization relative to National Comprehensive Cancer Network (NCCN) guidelines.We retrospectively reviewed SCLC records at our institution between January 1, 2003 and August 1, 2019 (n = 529). Patients were grouped by extensive-stage versus limited-stage and diagnosis date. Clinical, CT, MRI, and nuclear imaging data was collected. Imaging utilization was compared using Student's t-test or Kruskal-Wallis-test/Wilcoxon-Rank-Sums test. Survival was compared using Log-rank-test and Kaplan-Meier-curves.SCLC patients had a median survival of 290 days. Extensive-stage patients with SCLC demonstrated an increase in emergency imaging utilization when diagnosed in 2011-2019 compared to 2003-2010 (CT abdomen/pelvis p 0.001, CTA chest for pulmonary embolism p 0.01, CT head p 0.003). Limited-stage patients with SCLC demonstrated an increase in inpatient imaging utilization (CT abdomen/pelvis p 0.04) and decreased total/outpatient imaging utilization (CT chest-abdomen-pelvis p 0.05, CT head p 0.003) when diagnosed in 2011-2019 compared to 2003-2010. All patients with SCLC had decreased average number of bone-scan studies when diagnosed in 2011-2019 compared to 2003-2010 (Extensive-stage p 0.006, Limited-stage p 0.0006).Imaging utilization trends in the management of patients with SCLC at our institution differed between 2003 and 2010 and 2011-2019 reflecting the changes in the NCCN guidelines.

The Korean Society of Nuclear Medicine (KSNM) is celebrating its 60th anniversary in honor of the nuclear medicine professionals who have dedicated their efforts towards research, academics, and the more comprehensive clinical applications and uses of nuclear imaging modalities. Nuclear cardiology in Korea was at its prime time in the 1990s, but its growth was interrupted by a long pause. Despite the academic and practical challenges, nuclear cardiology in Korea now meets the second leap, attributed to the growth in molecular imaging tailored for many non-coronary diseases and the genuine values of nuclear myocardial perfusion imaging. In this review, we describe the trends, achievements, challenges, and perspectives of nuclear cardiology throughout the 60-year history of the KSNM.

The collection of large, heterogeneous electronic datasets and imaging from patients with cardiovascular disease (CVD) has lent itself to the use of sophisticated analysis using artificial intelligence (AI). AI techniques such as machine learning (ML) are able to identify relationships between data points by linking input to output variables using a combination of different functions, such as neural networks. In cardiovascular medicine, this is especially pertinent for classification, diagnosis, risk prediction and treatment guidance. Common cardiovascular data sources from patients include genomic data, cardiovascular imaging, wearable sensors and electronic health records (EHR). Leveraging AI in analysing such data points: (I) for clinicians: more accurate and streamlined image interpretation and diagnosis; (II) for health systems: improved workflow and reductions in medical errors; (III) for patients: promoting health with further education and promoting primary and secondary cardiovascular health prevention. This review addresses the need for AI in cardiovascular medicine by reviewing recent literature in different cardiovascular imaging modalities: electrocardiography, echocardiography, cardiac computed tomography, cardiac nuclear imaging, and cardiac magnetic resonance (CMR) imaging as well as the role of EHR. This review aims to conceptulise these studies in relation to their clinical applications, potential limitations and future opportunities and directions.

Infiltrative cardiomyopathies result from the deposition or anomalous storage of specific substances in the heart, leading to impaired cardiac function and heart failure. In this review, we describe the utility of a variety of imaging modalities for the diagnosis of infiltrative cardiomyopathies and provide algorithms for clinicians to use to evaluate patients with these disorders. We have divided infiltrative cardiomyopathies into two different categories: (1) infiltrative cardiomyopathies characterised by increased wall thickness (eg, cardiac amyloidosis and Anderson-Fabry disease (AFD)) and (2) infiltrative cardiomyopathies that can mimic ischaemic or dilated cardiomyopathies (eg, cardiac sarcoidosis (CS) and iron overload cardiomyopathy). Echocardiography is the first modality of choice for the evaluation of cardiomyopathies in either category, and the differential can be narrowed using cardiac magnetic resonance (CMR) and nuclear imaging techniques. The diagnosis of cardiac amyloidosis is supported with key findings seen on echocardiography, CMR and nuclear imaging, whereas AFD can be suggested by unique features on CMR. CMR and nuclear imaging are also important modalities for the diagnosis of CS, while iron overload cardiomyopathy is mostly diagnosed using tissue characterisation on CMR. Overall, multimodality imaging is necessary for the accurate non-invasive diagnosis of infiltrative cardiomyopathies, which is important to ensure appropriate treatment and prognostication.

BACKGROUND: Thyrotoxicosis is a common medical problem. Thyroid nuclear imaging with either I 123 or technetium-99m (Tc-99m) pertechnetate are used to determine the cause. Although I 123 has been the standard technique, Tc-99m pertechnetate is now commonly used, acceptable and easier to perform. The commonly used normal value of Tc-99m pertechnetate is 1–4%, but lower normal values have been reported in different populations. OBJECTIVE: Determine normal reference range of Tc-99m pertechne-tate thyroid uptake for thyroid scintigraphy in Saudi Arabia. DESIGN: Retrospective, cross-sectional. SETTING: Nuclear medicine service at tertiary care center in Riyadh. PATIENTS AND METHODS: We used data from biochemically euthyroid patients who underwent a thyroid Tc-99m pertechnetate scan while having parathyroid scintigraphy for hyperparathyroidism between April 2009 to April 2019. Medical records and biochemical thyroid function tests were reviewed and Tc-99m pertechnetate thyroid uptake values were determined for each patient. MAIN OUTCOME MEASURES: Thyroid uptake of Tc-99m pertechne-tate in euthyroid patients. SAMPLE SIZE: 167 RESULTS: The mean and median uptake of Tc-99m pertechnetate in euthyroid patients were 0.86% and 1.0%, respectively, and the inter-quartile range was 0.0–1.0%. The normal reference range in the study population was 0.2-2%. Thyroid uptake inversely correlated with age in females (r=−0.37, P P =.001), and for all patients (r=?0.39, P CONCLUSION: The range for normal thyroid Tc-99m pertechnetate was lower than the standard 1-4% range. Moreover, uptake decreased with age. Further studies are needed to establish the normal age-adjusted uptake for the thyroid Tc-99m pertechnetate scan. LIMITATIONS: Single center and retrospective. CONFLICT OF INTEREST: None.

Many methods applied to data acquired by various imaging modalities have been evaluated for their benefit in localizing lesions in magnetic resonance (MR) negative epilepsy patients. No approach has proven to be a stand‐alone method with sufficiently high sensitivity and specificity. The presented study addresses the potential benefit of the automated fusion of results of individual methods in presurgical evaluation. We collected electrophysiological, MR, and nuclear imaging data from 137 patients with pharmacoresistant MR‐negative/inconclusive focal epilepsy. A subgroup of 32 patients underwent surgical treatment with known postsurgical outcomes and histopathology. We employed a Gaussian mixture model to reveal several classes of gray matter tissue. Classes specific to epileptogenic tissue were identified and validated using the surgery subgroup divided into two disjoint sets. We evaluated the classification accuracy of the proposed method at a voxel‐wise level and assessed the effect of individual methods. The training of the classifier resulted in six classes of gray matter tissue. We found a subset of two classes specific to tissue located in resected areas. The average classification accuracy (i.e., the probability of correct classification) was significantly higher than the level of chance in the training group (0.73) and even better in the validation surgery subgroup (0.82). Nuclear imaging, diffusion‐weighted imaging, and source localization of interictal epileptic discharges were the strongest methods for classification accuracy. We showed that the automatic fusion of results can identify brain areas that show epileptogenic gray matter tissue features. The method might enhance the presurgical evaluations of MR‐negative epilepsy patients., There is no known stand‐alone imaging method for epileptogenic zone identification in nonlesional epilepsy. We examined the potential benefit of the automated fusion of results from individual methods. The proposed method can identify epileptogenic tissue with high accuracy at the voxel level, that is, at a millimeters scale.

Medical imaging is foundational in the care of children, and much of the medical imaging province depends on ionizing radiation: radiography, fluoroscopy, CT and nuclear imaging. Many considerations for this imaging in children are distinct in the domains of appropriate radiation use, other factors that determine examination quality, the opportunities to engage and educate through networking, and the translation of research efforts. Given these needs, it is worth approaching the contributions and their impact by the pediatric radiology community, especially to the enhancement of this value in the care of children.

Several types of gene- and cell-based therapeutics are now emerging in the cancer immunotherapy, transplantation, and regenerative medicine landscapes. Radionuclear-based imaging can be used as a molecular imaging tool for repetitive and non-invasive visualization as well as in vivo monitoring of therapy success. In this review, we discuss the principles of nuclear-based imaging and provide a comprehensive overview of its application in gene and cell therapy. This review aims to inform investigators in the biomedical field as well as clinicians on the state of the art of nuclear imaging, from probe design to available radiopharmaceuticals and advances of direct (probe-based) and indirect (transgene-based) strategies in both preclinical and clinical settings. Notably, as the nuclear-based imaging toolbox is continuously expanding, it will be increasingly incorporated into the clinical setting where the distribution, targeting, and persistence of a new generation of therapeutics can be imaged and ultimately guide therapeutic decisions., Graphical Abstract, This review aims to inform investigators and clinicians on the basic principles and new emerging radionuclear-based imaging approaches for the repetitive and non-invasive interrogation of gene and cell therapy and guide them in the advancement and clinical application of a new generation of therapeutics.

Cancer during pregnancy is increasingly diagnosed due to the trend of delaying pregnancy to a later age and probably also because of increased use of non-invasive prenatal testing for fetal aneuploidy screening with incidental finding of maternal cancer. Pregnant women pose higher challenges in imaging, diagnosis, and staging of cancer. Physiological tissue changes related to pregnancy makes image interpretation more difficult. Moreover, uncertainty about the safety of imaging modalities, fear of (unnecessary) fetal radiation, and lack of standardized imaging protocols may result in underutilization of the necessary imaging tests resulting in suboptimal staging. Due to the absence of radiation exposure, ultrasound and MRI are obvious first-line imaging modalities for detailed locoregional disease assessment. MRI has the added advantage of a more reproducible comprehensive organ or body region assessment, the ability of distant staging through whole-body evaluation, and the combination of anatomical and functional information by diffusion-weighted imaging which obviates the need for a gadolinium-based contrast-agent. Imaging modalities with inherent radiation exposure such as CT and nuclear imaging should only be performed when the maternal benefit outweighs fetal risk. The cumulative radiation exposure should not exceed the fetal radiation threshold of 100 mGy. Imaging should only be performed when necessary for diagnosis and likely to guide or change management. Radiologists play an important role in the multidisciplinary team in order to select the most optimal imaging strategies that balance maternal benefit with fetal risk and that are most likely to guide treatment decisions. Our aim is to provide an overview of possibilities and concerns in current clinical applications and developments in the imaging of patients with cancer during pregnancy. ispartof: INTERNATIONAL JOURNAL OF GYNECOLOGICAL CANCER vol:31 issue:3 pages:423-431 ispartof: location:England status: published

The coronavirus disease 2019 (COVID-19) outbreak has devastated the healthcare systems and economies of over 200 countries in just a few months. The etiological agent of COVID-19, SARS-CoV-2, is a highly contagious virus that can be transmitted by asymptomatic and symptomatic carriers alike. While in vitro testing techniques have allowed for population-wide screening, prognostic tools are required to assess the disease severity and therapeutic response, contributing to improve the patient clinical outcomes. Moreover, no specific antiviral against COVID-19 exists at the time of publication, severely limiting treatment against the infection. Hence, there is an urgent clinical need for innovative therapeutic strategies that may contribute to manage the COVID-19 outbreak and prevent future pandemics. Herein, we critically examine recent diagnostic, prognostic, and therapeutic advancements for COVID-19 in the field of radiopharmaceuticals. First, we summarize the gold standard techniques used to diagnose COVID-19, including in vitro assays and imaging techniques, and then discuss how radionuclide-based nuclear imaging provides complementary information for prognosis and treatment management of infected patients. Second, we introduce new emerging types of radiotherapies that employ radioimmunoconjugates, which have shown selective cytotoxic response in oncological studies, and critically analyze how these compounds could be used as therapeutic agents against SARS-CoV-2. Finally, this Perspective further discusses the emerging applications of radionuclides to study the behavior of pulmonary SARS-CoV-2 aerosol particles.

Immunotherapy has revolutionized the treatment of several malignancies. Notwithstanding the encouraging results, many patients do not respond to treatments. Evaluation of the efficacy of treatments is challenging and robust methods to predict the response to treatment are not yet available. The outcome of immunotherapy results from changes that treatment evokes in the tumor immune landscape. Therefore, a better understanding of the dynamics of immune cells that infiltrate into the tumor microenvironment may fundamentally help in addressing this challenge and provide tools to assess or even predict the response. Noninvasive imaging approaches, such as PET and SPECT that provide whole-body images are currently seen as the most promising tools that can shed light on the events happening in tumors in response to treatment. Such tools can provide critical information that can be used to make informed clinical decisions. Here, we review recent developments in the field of noninvasive cancer imaging with a focus on immunotherapeutics and nuclear imaging technologies and will discuss how the field can move forward to address the challenges that remain unresolved.

Validation study of simulation codes was performed based on the measurement of a sphere phantom and the National Electrical Manufacturers Association (NEMA) body phantoms. SIMIND and Prominence Processor were used for the simulation. Both source and density maps were generated using the characteristics of 99mTc energy. A full width at half maximum (FWHM) of the sphere phantom was measured and simulated. Simulated recovery coefficient and the background count coefficient of variation were also compared with the measured values in the body phantom study. When the two simulation codes were compared with actual measurements, maximum relative errors of FWHM values were 3.6% for Prominence Processor and -10.0% for SIMIND. The maximum relative errors of relative recovery coefficients exhibited 11.8% for Prominence Processor and -2.0% for SIMIND in the body phantom study. The coefficients of variation of the SPECT count in the background were significantly different among the measurement and two simulation codes. The simulated FWHM values and recovery coefficients paralleled measured results. However, the noise characteristic differed among actual measurements and two simulation codes in the background count statistics.

The concept of targeted radionuclide therapy (TRT) is the accurate and efficient delivery of radiation to disseminated cancer lesions while minimizing damage to healthy tissue and organs. Critical aspects for successful development of novel radiopharmaceuticals for TRT are: i) the identification and characterization of suitable targets expressed on cancer cells; ii) the selection of chemical or biological molecules which exhibit high affinity and selectivity for the cancer cell-associated target; iii) the selection of a radionuclide with decay properties that suit the properties of the targeting molecule and the clinical purpose. The Center for Radiopharmaceutical Sciences (CRS) at the Paul Scherrer Institute in Switzerland is privileged to be situated close to unique infrastructure for radionuclide production (high energy accelerators and a neutron source) and access to C/B-type laboratories including preclinical, nuclear imaging equipment and Swissmedic-certified laboratories for the preparation of drug samples for human use. These favorable circumstances allow production of non-standard radionuclides, exploring their biochemical and pharmacological features and effects for tumor therapy and diagnosis, while investigating and characterizing new targeting structures and optimizing these aspects for translational research on radiopharmaceuticals. In close collaboration with various clinical partners in Switzerland, the most promising candidates are translated to clinics for 'first-in-human' studies. This article gives an overview of the research activities at CRS in the field of TRT by the presentation of a few selected projects., Chimia, 74 (12), ISSN:0009-4293

Single-domain antibodies have the characteristics of small molecular weight, strong tissue penetration, and high affinity, and are widely used to construct molecular probes for disease diagnosis and treatment. This article reviews molecular imaging studies including positron emission tomography (PET), single-photon emission computed tomography/computed tomography (CT), PET/CT, and fluorescent imaging of molecular probes composed of single-domain antibodies against eight esophageal squamous cell carcinoma biological targets. These 8 targets are highly expressed on the membrane of esophageal squamous cell carcinoma cells and include epidermal growth factor receptor, human epidermal growth factor receptor 2, human epidermal growth factor receptor 3, hepatocyte growth factor receptor, vascular endothelial growth factor receptor 2, chemokine receptor 4, chemokine receptor 7, and carcinoembryonic antigen. The current problems and solutions are also discussed to provide a reference for future design of molecular imaging probes targeting esophageal squamous cell carcinoma.

Since its development in the late 1970s, 18F-FDG has been a major driver of basic science and translational discoveries, which have revolutionized the day-to-day clinical practice of nuclear imaging ([1][1]). Initially launched as a tracer for imaging brain metabolism, 18F-FDG rapidly found its

123I-15-(p-iodophenyl)-3(R,S)-methylpentadecanoic acid ([123I]BMIPP), a fatty acid analog, is widely used for the diagnosis of cardiac diseases. Feeding condition is one of the important factors in the myocardial fatty acid uptake, which may also affect myocardial accumulation of [123I]BMIPP and image quality of [123I]BMIPP scintigraphy. However, the relationship between the myocardial accumulation of [123I]BMIPP and the feeding condition is not entirely clear. Therefore, we determined the myocardial accumulation of [125I]BMIPP in mice at various metabolic statuses induced by fasting in comparison with the hepatic accumulation. Fed or fasted (6-, 12-, and 24-h fasted) mice were intravenously injected with [125I]BMIPP (35.2–75.0 kBq, 4 nmol). Radioactivities in the heart and liver were measured at 1, 5, 10, 30, 60, and 120 min after the injection (n = 5–15/time point for each group), and then, the heart-to-liver (H/L) ratios were calculated. The myocardial accumulation level of [125I]BMIPP in the fed group was almost the same as that in the 6-h-fasted group at each time point, although it was decreased by 12- and 24-h fasting. The H/L ratios of [125I]BMIPP accumulation level were significantly decreased by fasting (1.92 ± 0.22, 1.45 ± 0.13, 1.12 ± 0.13, and 0.91 ± 0.15 at 10 min, and 3.30 ± 0.62, 2.09 ± 0.35, 1.79 ± 0.34, and 1.27 ± 0.06 at 30 min after the injection, respectively, for the fed group and the 6-, 12-, and 24-h-fasted groups; p

We present not‐yet‐seen multimodal images of a 55‐year‐old female patient with isolated atrial amyloidosis (IAA) who clinically suffered from multiple atrial arrhythmias and heart failure symptoms with preserved left ventricular ejection fraction. We aim to show structural and functional abnormalities detected by electrophysiological voltage mapping, cardiac magnetic resonance imaging (MRI) [cMRI; atrial strain measurements, late gadolinium enhancement (LGE) visualization], and 99mTc‐DPD scintigraphy. Bipolar voltage mapping performed during two electrophysiological procedures showed diffuse left atrial low‐voltage areas (bipolar

Magnetic resonance imaging (MRI) is widely used for screening, diagnosis, image-guided therapy, and scientific research. A significant advantage of MRI over other imaging modalities such as computed tomography (CT) and nuclear imaging is that it clearly shows soft tissues in multi-contrasts. Compared with other medical image super-resolution (SR) methods that are in a single contrast, multi-contrast super-resolution studies can synergize multiple contrast images to achieve better super-resolution results. In this paper, we propose a one-level non-progressive neural network for low up-sampling multi-contrast super-resolution and a two-level progressive network for high up-sampling multi-contrast super-resolution. Multi-contrast information is combined in high-level feature space. Our experimental results demonstrate that the proposed networks can produce MRI super-resolution images with good image quality and outperform other multi-contrast super-resolution methods in terms of structural similarity and peak signal-to-noise ratio. Also, the progressive network produces a better SR image quality than the non-progressive network, even if the original low-resolution images were highly down-sampled., Comment: 10 figures, 5 tables, 11 pages

Nuclear imaging is used in the evaluation of painful arthroplasties for diagnosing loosening or periprosthetic joint infection (PJI). The purpose of this systematic review is to depict the reproducibility of the various nuclear imaging modalities used in the assessment of painful hip and knee arthroplasties. A systematic review of the literature was conducted with a comprehensive search of MEDLINE to identify clinical studies investigating the intra-and inter-observer agreement of nuclear imaging modalities in diagnosing PJI and mechanical loosening. A total of 3.000 studies, published between 2004 and 2020, were reviewed and 16 studies met the inclusion criteria. Quality assessment identified concerns with regard to the internal validity in approximately 40% of the included studies. A meta-analysis could not be performed because of insufficient available clinical data. The intra-observer agreement was poorly investigated. The included studies reported an inter-observer agreement of “slight” to “excellent” for bone scintigraphy, “moderate” to “substantial” for leukocyte scintigraphy, “substantial” to “almost perfect” for combined leukocyte and bone marrow scintigraphy, and “fair” to “substantial” for anti-granulocyte scintigraphy. Hybrid imaging with SPECT/CT and FDG-PET/CT demonstrated “substantial” and “almost perfect” inter-observer agreement for symptomatic hip prostheses, respectively. The reproducibility of nuclear imaging is underreported in clinical studies investigating painful knee and hip arthroplasties. Moreover, the included studies demonstrated methodological concerns with a high risk of bias. The available evidence demonstrated a wide range of inter-observer agreement using scintigraphy. Hybrid imaging with SPECT/CT and FDG-PET/CT may improve the accuracy of interpretation and reproducibility. However, literature provides limited data to support this assumption.

Increased mortality rates from infectious diseases is a growing public health concern. Successful management of acute bacterial infections requires early diagnosis and treatment, which are not always easy to achieve. Structural imaging techniques such as CT and MRI are often applied to this problem. However, these methods generally rely on secondary inflammatory changes and are frequently not specific to infection. The use of nuclear medicine techniques can add crucial complementary information, allowing visualization of infectious pathophysiology beyond morphologic imaging. This review will discuss the current structural and functional imaging techniques used for the diagnosis of bacterial infection and their roles in different clinical scenarios. We will also present several new radiotracers in development, with an emphasis on probes targeting bacteria-specific metabolism. As highlighted by the current coronavirus disease 2019 epidemic, caused by the novel severe acute respiratory syndrome coronavirus 2, similar thinking may apply in imaging viral pathogens; for this case, prominent effects on host proteins, most notably angiotensin-converting enzyme 2, might also provide worthwhile imaging targets.

COVID-19 has infected millions of people, with an estimated total dead in the hundreds of thousands. This has significantly impacted health care, including who is delivering it, how it is delivered, and how it is taught. This article describes challenges of the COVID-19 pandemic from the perspective of a Canadian nuclear medicine resident, including new risks with nuclear imaging, navigating new and sometimes challenging guidelines, as well as working and living within the confines of social distancing.

Cardiac amyloidosis is a heterogeneous and challenging diagnostic disease with poor prognosis that is now being altered by introduction of new therapies. Echocardiography remains the first-line imaging tool, and when disease is suspected on echocardiography, cardiac magnetic resonance imaging and nuclear imaging play critical roles in the non-invasive diagnosis and evaluation of cardiac amyloidosis. Advances in multi-modality cardiac imaging allowing earlier diagnosis and initiation of novel therapies have significantly improved the outcomes in these patients. Cardiac imaging also plays important roles in the risk stratification of patients presenting with cardiac amyloidosis. In the current review, we provide a clinical and imaging focused update, and importantly outline the imaging protocols, diagnostic and prognostic utility of multimodality cardiac imaging in the assessment of cardiac amyloidosis.

The expansion of cancer therapeutics has paved the way for improved cancer-related outcomes. Cardiotoxicity from cancer therapy occurs in a small but significant subset of patients, is often poorly understood, and contributes to adverse outcomes at all stages of cancer treatment. Given the often-idiopathic occurrence of cardiotoxicity, novel strategies are needed for risk-stratification and early identification of cancer patients experiencing cardiotoxicity. Clinical and research tools extending from imaging to blood-based biomarkers and pluripotent stem cells are being explored as methods to study the cardiovascular impact of various cancer treatments. Here we provide an overview of tools currently available for evaluation of cardiotoxicity and highlight novel techniques in development aimed at understanding underlying pathophysiologic mechanisms.

Aims To evaluate the diagnosis and imaging of patients with suspected endocarditis and the management in routine clinical practice across Europe, the EACVI Scientific Initiatives Committee performed a survey across European centres. In particular, the routine use of echocardiography, advanced imaging modalities and multidisciplinary team was explored. Methods and results A total of 100 European Echocardiography Laboratories from 29 different countries responded to the survey, which consisted of 20 questions. For most of the use of echocardiography and advanced imaging, answers from the centres were relatively homogeneous and demonstrated good adherence to current recommendations. In particular, two-thirds of centres report the use of a specific endocarditis team for decision-making. Echocardiography plays a key role in the diagnosis and management of endocarditis. Nuclear imaging modalities are broadly available among the centres and are mainly used in prosthetic valve endocarditis and cardiac device-related infective endocarditis. Computed tomography (CT) is widely available and used to assess for structural valve abnormalities, neurological complications, and to preoperative assessment of the coronary arteries. Most institutions provide structured patients follow-up following hospital discharge. Conclusion In Europe, a relatively homogenous adherence to current recommendation was observed for most diagnostic and management including the follow-up of patients with endocarditis. Decision-making is most commonly performed by a multidisciplinary team. Echocardiography remains the first line and central imaging modality for patient diagnosis and assessment, but 60% of centres also commonly use CT, whilst positron emission tomography imaging is used in patients with prosthetic valve endocarditis or device infection.

Clinicians are beginning to understand the importance of quantification for use in medicine, particularly nuclear medicine. With the recent introduction of mandates by CMS, ASNC, and the SNMMI for quantification, it is not surprising that professional papers are beginning to be published on the topic. One recent publication paper by Zhao et al. demonstrates the misunderstanding that is plaguing the field of modern nuclear medicine. The second publication by Dorbala et al. discusses a major flaw in the current understanding of redistribution measurements of isotopes such as Sestamibi and Tetrofsomin

Дилатаційна кардіоміопатія (ДКМП) визначається наявністю дилатації лівого шлуночка або обох шлуночків та систолічною дисфункцією за відсутності патологічних умов навантаження або ішемічної хвороби серця, достатніх, щоб пояснити ці зміни. Це гетерогенна група захворювань, що часто має генетичне підґрунтя. Серцево-судинна візуалізація є надзвичайно важливою для встановлення діагнозу, оцінювання прогнозу та лікування. Мультимодальний підхід до візуалізації забезпечує найповнішу оцінку всіх аспектів, пов’язаних із цим захворюванням. Цей документ має на меті забезпечити детальні рекомендації з використання мультимодальної візуалізації відповідно до клінічних вимог з урахуванням сучасних світових доказових даних і рекомендацій та з адаптацією до існуючих практик в Україні. Вибір того чи іншого засобу візуалізації має базуватися на конкретних клінічних умовах та індивідуальному контексті. Методи візуалізації розглядаються з точки зору «клінічно релевантних» та засобів, що «можуть використовуватися». До сьогодні лишаються певні пробіли в доказовій базі щодо впливу мультимодальної візуалізації на ведення та лікування пацієнтів з ДКМП, що свідчить про важливість подальших досліджень у цьому напрямку.

Abnormalities in the cardiac sympathetic nervous system have been documented in various heart diseases and have been directly implicated in their pathogenesis and disease progression. Noninvasive techniques using single-photon-emitting radiotracers for planar scintigraphy and single-photon emission computed tomography, and positron-emitting tracers for positron emissions tomography, have been used to characterize the cardiac sympathetic nervous system with norepinephrine analogs [123I]meta-iodobenzylguanidine for planar and single-photon emission computed tomography imaging and [11C]meta-hydroxyephedrine for positron emissions tomography. Their usefulness in prognostication and risk stratification for cardiac events has been demonstrated. This review bridges basic and clinical research and focuses on applying an understanding of tracer kinetics and neuronal biology, to aid in the interpretation of nuclear imaging of cardiac sympathetic innervation.

Right ventricular (RV) function and autonomic dysfunction are important determinants of morbidity and mortality in patients with pulmonary arterial hypertension (PAH). Although successful in animal studies, effects of beta-blocker therapy on RV function in clinical trials were disappointing. To understand this discrepancy, we studied whether beta-blocker therapy changes RV sympathetic activity. Idiopathic PAH (IPAH) patients received beta-blocker therapy (uptitrated to a maximal tolerated dose) and underwent cardiac magnetic resonance imaging, right heart catheterization, and a [ 11 C]-hydroxyephedrine positron emission tomography ([ 11 C]HED PET) scan at baseline to determine, respectively, RV ejection fraction (RVEF), RV pressures, and sympathetic activity. [ 11 C]HED, a norepinephrine analogue, allows determination of sympathetic innervation of the RV. [ 11 C]HED retention index reflects norepinephrine transporter activity. As a consequence of excessive catecholamine levels in the synaptic cleft, this transporter may be downregulated. Therefore, low [ 11 C]HED retention index indicates high sympathetic activity. 13 IPAH patients underwent [ 11 C]HED PET scans at baseline and after bisoprolol treatment. Although heart rate was reduced, systemic modulation of autonomic activity by bisoprolol did not affect local RV sympathetic nerve activity, RV function, or RV wall tension. In PAH patients, RV [ 11 C]HED retention index was lower compared to LV tracer uptake (p

In this comprehensive review we present an overview of the main aspects of classification, radiological signs and nuclear imaging findings of typical lung carcinoids (TCs). A literature search on the PubMed literature database was conducted using the terms “positron emission tomography—PET”, “PET/CT”, “FDG”, “18F-fluorodeoxyglucose”, “MDCT—Contrast-enhanced multi-detector computed tomography” “typical lung carcinoid” “SRS—Somatostatin receptor scintigraphy”, “68 Ga DOTA-peptides” alone and in combination, extending until December 2019. TCs are rare tumours, accounting for only 1–2% of all pulmonary neoplasms. They tend to occur usually in the fourth-to-sixth decade of life and are characterized by mitotic count of less 2/2 mm2 and absent necrosis. Contrast-enhanced multi-detector computed tomography (MDCT) is the most largely used imaging modality for the localization, characterization and staging of lung TCs. Nuclear medicine imaging assists MDCT in the diagnosis of these rare tumour entities, especially by somatostatin receptor scintigraphy, PET imaging with Gallium-68-tetrazacyclododecanetetraacetic acid (68 Ga DOTA-peptides) and with 18F-fluorodeoxyglucose (18F-FDG). TCs of lung are rare lung tumours placed within a defined classification system. MDCT morphological features combined with functional nuclear medicine imaging are an important tool for the detection of these rare neoplasms and contribute to their characterisation and staging. Therefore, MDCT and nuclear medicine parameters could give a preliminary orientation before the pathological examination, on the biological behaviour and the prognostic outcome of TCs.

This review discusses nuclear imaging of inflammation using molecular probes beyond fluoro-d-glucose, is structured by cellular targets, and focuses on those tracers that have been successfully applied clinically.

Background::The rising incidence rate of prostate cancer (PCa) has promoted the development of new diagnostic and therapeutic radiopharmaceuticals during the last decades. Promising improvements have been achieved in clinical practice using prostate specific membrane antigen (PSMA) labeled agents, including specific antibodies and small molecular weight inhibitors. Focusing on molecular docking studies, this review aims to highlight the progress in the design of PSMA targeted agents for a potential use in nuclear medicine.Results::Although the first development of radiopharmaceuticals able to specifically recognize PSMA was exclusively oriented to macromolecule protein structure such as radiolabeled monoclonal antibodies and derivatives, the isolation of the crystal structure of PSMA served as the trigger for the synthesis and the further evaluation of a variety of low molecular weight inhibitors. Among the nuclear imaging probes and radiotherapeutics that have been developed and tested till today, labeled Glutamate-ureido inhibitors are the most prevalent PSMA-targeting agents for nuclear medicine applications.Conclusion::PSMA represents for researchers the most attractive target for the detection and treatment of patients affected by PCa using nuclear medicine modalities. [99mTc]MIP-1404 is considered the tracer of choice for SPECT imaging and [68Ga]PSMA-11 is the leading diagnostic for PET imaging by general consensus. [18F]DCFPyL and [18F]PSMA-1007 are clearly the emerging PET PSMA candidates for their great potential for a widespread commercial distribution. After paving the way with new imaging tools, academic and industrial R&Ds are now focusing on the development of PSMA inhibitors labeled with alpha or beta minus emitters for a theragnostic application.

Understanding the subclinical pathway to cellular engraftment following haemopoietic stem cell transplantation (HSCT) has historically been limited by infrequent marrow biopsies, which increase the risk of infections and might poorly represent the health of the marrow space. Nuclear imaging could represent an opportunity to evaluate the entire medullary space non-invasively, yielding information about cell number, proliferation, or metabolism. Because imaging is not associated with infectious risk, it permits assessment of neutropenic timepoints that were previously inaccessible. This Viewpoint summarises the data regarding the use of nuclear medicine techniques to assess the phases of HSCT: pre-transplant homoeostasis, induced aplasia, early settling and engraftment of infused cells, and later recovery of lymphocytes that target cancers or mediate tolerance. Although these data are newly emerging and preliminary, nuclear medicine imaging approaches might advance our understanding of HSCT events and lead to novel recommendations to enhance outcomes.

The 2019 American College of Cardiology Scientific Sessions displayed innovation in many areas for the evaluation and management of cardiovascular disease from preventive evaluation and care to advanced interventions. Imaging played a central role in these developments with a highlight of the conference being the imaging research presented. This review will summarize key imaging studies which were presented at this scientific meeting which will lead to innovation in the evaluation and management of cardiovascular disease. Experts in nuclear imaging (DW/MA), echocardiography (MS), cardiac magnetic resonance (SL), and cardiac computed tomography (RB) selected abstracts which they found to be of particular interest to the multimodality imaging audience and were integrated into this review (LP).

Purpose Fracture-related infection (FRI) is a complication of surgical fracture treatment and can be challenging to diagnose. Recent studies show promising results for the use of either FDG-PET/CT or WBC/anti-granulocyte scintigraphy. The purpose of this pictorial essay is to outline recent developments in nuclear imaging techniques to diagnose FRI. Methods The current literature on this topic is reviewed. Additionally, three examples of patients who underwent nuclear imaging as part of their clinical work-up and surgical treatment for FRI are presented. Results Based on recent retrospective studies, FDG-PET/CT (accuracy 0.83) and WBC scintigraphy with SPECT/CT (accuracy 0.92) both have a good diagnostic accuracy for diagnosing fracture-related infection. Nuclear imaging contributes to a correct diagnosis in patients with FRI. Conclusion Retrospective studies show promising results for both FDG-PET/CT and WBC scintigraphy with SPECT/CT in diagnosing FRI. A prospective, multicenter study (IFI trial), directly comparing MRI, FDG-PET/CT, and WBC scintigraphy with SPECT/CT in patients with suspected FRI, is currently in progress.

Catheter ablation is an effective treatment option for ventricular tachycardia (VT) in patients with non-ischaemic cardiomyopathy (NICM). The heterogeneous nature of NICM aetiologies and VT substrate in patients with NICM play a role in long-term ablation outcomes in this population. Over the past decades, more precise identification of NICM aetiologies and better characterisation of various substrates have been made. Application of multimodal imaging has greatly contributed to the accurate diagnosis of NICM subtypes and improved VT ablation strategies. This article summarises the current knowledge of multimodal imaging used in the characterisation of non-ischaemic NICM substrates, procedural planning and image integration for the optimisation of VT ablation.

Cardiac amyloidosis is an infiltrative disorder caused by transthyretin or immunoglobulin free light-chain deposition, which determines clinical disease with similar phenotype but different time course, prognosis and therapy. Multimodality imaging is the cornerstone for disease diagnosis and management. Multimodality imaging has revolutionized the approach to the disease favoring its awareness and simplifying its diagnosis, especially in ATTR cardiac amyloidosis. This describes the different imaging tools, from the traditional to the more novel ones, and highlights the different approach in each different setting (prognosis, subtyping, prognosis, monitoring disease progression, and response to therapy).

Transthyretin amyloid cardiomyopathy (ATTR-CM) has emerged as an increasingly identified etiology of heart failure. Fortunately, the disease now has an approved therapy, with many others under development. Assessment of prognosis in ATTR-CM is critical to inform patients about the disease course and guide clinical decisions. This review discusses the evidence behind clinical, biomarker, and imaging findings that inform prognosis in patients with ATTR-CM and can assist providers in the shared decision-making process during management of this disease., Central Illustration, Highlights • Prognostic factors for ATTR-CM can guide patient expectations and inform clinical decisions. • Clinical features, blood biomarkers, and imaging obtained during workup for ATTR-CM convey prognostic information. • Further studies in determining the incremental value of prognostic factors are warranted.

Radioembolization gains continuous traction as a primarily palliative radiation treatment for hepatic tumours. A form of nuclear medicine therapy, Yttrium-90 containing microspheres are catheter guided and injected into the right, left, or a specifically selected hepatic artery. A multitude of comprehensive planning steps exist to ensure a thorough and successful treatment. Clear clinical and physiological guidelines have been established and nuclear imaging is used to plan and verify dose distributions. Radioembolization's treatment rationale is based on tumour and blood vessel dynamics that allow a targeted treatment approach. However, radioembolization's dosimetry is grossly oversimplified. In fact, the currently utilized clinical dosimetric standards (e.g. partition method) have persisted since the 1990s. Moreover, the multitude of radioembolization's intertwining components lies disjointed within the literature. Particularly relevant to new readers, this review provides a methodical guide that presents the treatment rationale behind every clinical step. The emerging dosimetry methods and its factors are further discussed to provide a comprehensive review on an essential research direction.

In the Last decades, nanotechnology has provided novel and alternative methodologies and tools in the field of medical oncology, in order to tackle the issues regarding the control and treatment of cancer in modern society. In particular, the use of gold nanoparticles (AuNPs) in radiopharmaceutical development has provided various nanometric platforms for the delivery of medically relevant radioisotopes for SPECT/PET diagnosis and/or radionuclide therapy. In this review, we intend to provide insight on the methodologies used to obtain and characterize radiolabeled AuNPs while reporting relevant examples of AuNPs developed during the last decade for applications in nuclear imaging and/or radionuclide therapy, and highlighting the most significant preclinical studies and results.

Purpose TSPO PET imaging may hold promise as a single-step diagnostic work-up for clinical immunopsychiatry. This review paper on the clinical applicability of TSPO PET for primary psychiatric disorders discusses if and why TSPO PET imaging might become the first clinical immunopsychiatry biomarker and the investment prerequisites and scientific advancements needed to accommodate this transition from bench to bedside. Methods We conducted a systematic search of the literature to identify clinical studies of TSPO PET imaging in patients with primary psychiatric disorders. We included both original case-control studies as well as longitudinal cohort studies of patients with a primary psychiatric diagnosis. Results Thirty-one original studies met our inclusion criteria. In the field of immunopsychiatry, TSPO PET has until now mostly been studied in schizophrenia and related psychotic disorders, and to a lesser extent in mood disorders and neurodevelopmental disorders. Quantitative TSPO PET appears most promising as a predictive biomarker for the transdiagnostic identification of subgroups or disease stages that could benefit from immunological treatments, or as a prognostic biomarker forecasting patients' illness course. Current scanning protocols are still too unreliable, impractical and invasive for clinical use in symptomatic psychiatric patients. Conclusion TSPO PET imaging in its present form does not yet offer a sufficiently attractive cost-benefit ratio to become a clinical immunopsychiatry biomarker. Its translation to psychiatric clinical practice will depend on the prioritising of longitudinal research and the establishment of a uniform protocol rendering clinically meaningful TSPO uptake quantification at the shortest possible scan duration without arterial cannulation.

Purpose: White blood cell (WBC) scintigraphy is considered the gold-standard nuclear imaging technique for diagnosing fracture-related infection (FRI). Correct interpretation of WBC scans in FRI is important since a false positive or false negative diagnosis has major consequences for the patient in terms of clinical decision-making. The European Association of Nuclear Medicine (EANM) guideline for correct analysis and interpretation of WBC scans recommends semiquantitative analysis of visually equivocal scans. Therefore, this study aims to assess the diagnostic accuracy of semiquantitative analysis of visually equivocal WBC scans for diagnosing FRI. Methods: A retrospective single-center study was performed in consecutive patients who received WBC scintigraphy in the diagnostic work-up for FRI between February 2012 and January 2017. All the visually equivocal scans were analysed using semiquantitative analysis by comparing leukocyte uptake in the manually selected suspected infection focus with the contralateral bone marrow (L/R ratio). Cut-off points for a ‘positive’ scan result of >0%, >10% and >20% leukocyte increase between the early and late scans were used in separate analyses. The discriminative ability was quantified by calculating the sensitivity, specificity and diagnostic accuracy. Results: In total, 153 WBC scans were eligible for inclusion. After visual assessment of all the scans, 28 visually equivocal scans were included. Dichotomization of the ratios using the cut-off of >0% resulted in a sensitivity of 30%, a specificity of 45% and a diagnostic accuracy of 40%. The >10% cut-off point resulted in a sensitivity of 18%, a specificity of 82% and a diagnostic accuracy of 66%. The >20% cut-off point resulted in a sensitivity of 0%, a specificity of 89% and a diagnostic accuracy of 67%. Conclusion: Semiquantitative analysis of visually equivocal WBC scans is insufficient for correctly diagnosing FRI.

Cancer is one of the leading causes of death in the world. A cancer-targeted multifunctional probe labeled with the radionuclide has been developed to provide multi-modalities for NIR fluorescence and nuclear imaging (PET, SPECT), for photothermal therapy (PTT), and targeted radionuclide therapy of cancer. In this study, synthesis, characterization, in vitro, and in vivo biological evaluation of the cyanine-based probe (DOTA-NIR790) were demonstrated. The use of cyanine dyes for the selective accumulation of cancer cells were used to achieve the characteristics of tumor markers. Therefore, all kinds of organ tumors can be targeted for diagnosis and treatment. The DOTA-NIR790 labeled with lutetium-111 could detect original or metastatic tumors by using SPECT imaging and quantify tumor accumulation. The β-emission of 177Lu-DOTA-NIR790 can be used for targeted radionuclide therapy of tumors. The DOTA-NIR790 enabled imaging by NIR fluorescence and by nuclear imaging (SPECT) to monitor in real-time the tumor accumulation and the situation of cancer therapy, and to guide the surgery or the photothermal therapy of the tumor. The radionuclide-labeled heptamethine cyanine based probe (DOTA-NIR790) offers multifunctional modalities for imaging and therapies of cancer.