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European Heart Journal Oct 2023
Topics: Humans; Endocarditis; Endocarditis, Bacterial; Heart Valve Prosthesis; Prosthesis-Related Infections; Positron Emission Tomography Computed Tomography; Fluorodeoxyglucose F18; Radiopharmaceuticals
PubMed: 37622656
DOI: 10.1093/eurheartj/ehad193 -
Radiology. Imaging Cancer Jul 2023Theranostics is the combination of two approaches-diagnostics and therapeutics-applied for decades in cancer imaging using radiopharmaceuticals or paired... (Review)
Review
Theranostics is the combination of two approaches-diagnostics and therapeutics-applied for decades in cancer imaging using radiopharmaceuticals or paired radiopharmaceuticals to image and selectively treat various cancers. The clinical use of theranostics has increased in recent years, with U.S. Food and Drug Administration (FDA) approval of lutetium 177 (Lu) tetraazacyclododecane tetraacetic acid octreotate (DOTATATE) and Lu-prostate-specific membrane antigen vector-based radionuclide therapies. The field of theranostics has imminent potential for emerging clinical applications. This article reviews critical areas of active clinical advancement in theranostics, including forthcoming clinical trials advancing FDA-approved and emerging radiopharmaceuticals, approaches to dosimetry calculations, imaging of different radionuclide therapies, expanded indications for currently used theranostic agents to treat a broader array of cancers, and emerging ideas in the field. Molecular Imaging, Molecular Imaging-Cancer, Molecular Imaging-Clinical Translation, Molecular Imaging-Target Development, PET/CT, SPECT/CT, Radionuclide Therapy, Dosimetry, Oncology, Radiobiology © RSNA, 2023.
Topics: United States; Male; Humans; Precision Medicine; Radiopharmaceuticals; Positron Emission Tomography Computed Tomography; Radioisotopes; Neoplasms
PubMed: 37477566
DOI: 10.1148/rycan.220157 -
European Heart Journal. Cardiovascular... Oct 2023In this EACVI clinical scientific update, we will explore the current use of multi-modality imaging in the diagnosis, risk stratification, and follow-up of patients with...
In this EACVI clinical scientific update, we will explore the current use of multi-modality imaging in the diagnosis, risk stratification, and follow-up of patients with aortic stenosis, with a particular focus on recent developments and future directions. Echocardiography is and will likely remain the key method of diagnosis and surveillance of aortic stenosis providing detailed assessments of valve haemodynamics and the cardiac remodelling response. Computed tomography (CT) is already widely used in the planning of transcutaneous aortic valve implantation. We anticipate its increased use as an anatomical adjudicator to clarify disease severity in patients with discordant echocardiographic measurements. CT calcium scoring is currently used for this purpose; however, contrast CT techniques are emerging that allow identification of both calcific and fibrotic valve thickening. Additionally, improved assessments of myocardial decompensation with echocardiography, cardiac magnetic resonance, and CT will become more commonplace in our routine assessment of aortic stenosis. Underpinning all of this will be widespread application of artificial intelligence. In combination, we believe this new era of multi-modality imaging in aortic stenosis will improve the diagnosis, follow-up, and timing of intervention in aortic stenosis as well as potentially accelerate the development of the novel pharmacological treatments required for this disease.
Topics: Humans; Consensus; Artificial Intelligence; Aortic Valve Stenosis; Aortic Valve; Multimodal Imaging
PubMed: 37395329
DOI: 10.1093/ehjci/jead153 -
Radiologia Oct 2023Chronic expansive hematoma (CEH) is a rare lesion, characterized by the persistence and increase in size of an hematoma for a period greater than one month since the...
Chronic expansive hematoma (CEH) is a rare lesion, characterized by the persistence and increase in size of an hematoma for a period greater than one month since the initial hemorrhage. The clinical importance of this pathology is due to the fact that it can simulate malignant soft tissue neoplasms, both clinically as a result of its progressive growth and radiologically for its findings in imaging studies. This article will review three cases of CEH in different scenarios, explaining the radiological findings in different imaging techniques such as ultrasound, computed tomography (CT), magnetic resonance imaging (MRI), and PET-CT.
Topics: Humans; Hematoma; Magnetic Resonance Imaging; Positron Emission Tomography Computed Tomography; Tomography, X-Ray Computed
PubMed: 37858357
DOI: 10.1016/j.rxeng.2023.09.006 -
Journal of Nuclear Medicine : Official... Sep 2023Radiolabeled fibroblast activation protein (FAP) inhibitors (FAPIs) have shown promise as cancer diagnostic agents; however, the relatively short tumor retention of...
Radiolabeled fibroblast activation protein (FAP) inhibitors (FAPIs) have shown promise as cancer diagnostic agents; however, the relatively short tumor retention of FAPIs may limit their application in radioligand therapy. In this paper, we report the design, synthesis, and evaluation of a FAPI tetramer. The aim of the study was to evaluate the tumor-targeting characteristics of radiolabeled FAPI multimers in vitro and in vivo, thereby providing information for the design of FAP-targeted radiopharmaceuticals based on the polyvalency principle. FAPI tetramers were synthesized on the basis of FAPI-46 and radiolabeled with Ga, Cu, and Lu. In vitro FAP-binding characteristics were identified using a competitive cell-binding experiment. To evaluate their pharmacokinetics, small-animal PET, SPECT, and ex vivo biodistribution analyses were performed on HT-1080-FAP and U87MG tumor-bearing mice. In addition, the 2 tumor xenografts received radioligand therapy with Lu-DOTA-4P(FAPI), and the antitumor efficacy of the Lu-FAPI tetramer was evaluated and compared with that of the Lu-FAPI dimer and monomer. Ga-DOTA-4P(FAPI) and Lu-DOTA-4P(FAPI) were highly stable in phosphate-buffered saline and fetal bovine serum. The FAPI tetramer exhibited high FAP-binding affinity and specificity both in vitro and in vivo. Ga-, Cu-, and Lu-labeled FAPI tetramers exhibited higher tumor uptake, longer tumor retention, and slower clearance than FAPI dimers and FAPI-46 in HT-1080-FAP tumors. The uptake (percentage injected dose per gram) of Lu-DOTA-4P(FAPI), Lu-DOTA-2P(FAPI), and Lu-FAPI-46 in HT-1080-FAP tumors at 24 h was 21.4 ± 1.7, 17.1 ± 3.9, and 3.4 ± 0.7, respectively. Moreover, Ga-DOTA-4P(FAPI) uptake in U87MG tumors was approximately 2-fold the uptake of Ga-DOTA-2P(FAPI) (SUV, 0.72 ± 0.02 vs. 0.42 ± 0.03, < 0.001) and more than 4-fold the uptake of Ga-FAPI-46 (0.16 ± 0.01, < 0.001). In the radioligand therapy study, remarkable tumor suppression was observed with the Lu-FAPI tetramer in both HT-1080-FAP and U87MG tumor-bearing mice. The satisfactory FAP-binding affinity and specificity, as well as the favorable in vivo pharmacokinetics of the FAPI tetramer, make it a promising radiopharmaceutical for theranostic applications. Improved tumor uptake and prolonged retention of the Lu-FAPI tetramer resulted in excellent characteristics for FAPI imaging and radioligand therapy.
Topics: Humans; Animals; Mice; Tissue Distribution; Gallium Radioisotopes; Neoplasms; Protein Binding; Biological Transport; Positron Emission Tomography Computed Tomography
PubMed: 37321827
DOI: 10.2967/jnumed.123.265599 -
Current Opinion in Rheumatology Nov 2023Imaging techniques such as MRI, ultrasound and PET/computed tomography (CT) have roles in the detection, diagnosis and management of myositis or idiopathic inflammatory... (Review)
Review
PURPOSE OF REVIEW
Imaging techniques such as MRI, ultrasound and PET/computed tomography (CT) have roles in the detection, diagnosis and management of myositis or idiopathic inflammatory myopathy (IIM). Imaging research has also provided valuable knowledge in the understanding of the pathology of IIM. This review explores the latest advancements of these imaging modalities in IIM.
RECENT FINDINGS
Recent advancements in imaging of IIM have seen a shift away from manual and qualitative analysis of the images. Quantitative MRI provides more objective, and potentially more sensitive characterization of fat infiltration and inflammation in muscles. In addition to B-mode ultrasound changes, shearwave elastography offers a new dimension to investigating IIM. PET/CT has the added advantage of including IIM-associated findings such as malignancies.
SUMMARY
It is evident that MRI, ultrasound and PET/CT have important roles in myositis. Continued technological advancement and a quest for more sophisticated applications help drive innovation; this has especially been so of machine learning/deep learning using artificial intelligence and the developing promise of texture analysis.
Topics: Humans; Positron Emission Tomography Computed Tomography; Artificial Intelligence; Myositis; Inflammation; Muscle, Skeletal
PubMed: 37656661
DOI: 10.1097/BOR.0000000000000975 -
Thrombosis Research Jun 2024The first-choice imaging test for visualization of thromboemboli in the pulmonary vasculature in patients with suspected acute pulmonary embolism (PE) is multidetector... (Review)
Review
The first-choice imaging test for visualization of thromboemboli in the pulmonary vasculature in patients with suspected acute pulmonary embolism (PE) is multidetector computed tomography pulmonary angiography (CTPA) - a readily available and widely used imaging technique. Through technological advancements over the past years, alternative imaging techniques for the diagnosis of PE have become available, whilst others are still under investigation. In particular, the evolution of artificial intelligence (AI) is expected to enable further innovation in diagnostic management of PE. In this narrative review, current CTPA techniques and the emerging technology photon-counting CT (PCCT), as well as other modern imaging techniques of acute PE are discussed, including CTPA with iodine maps based on subtraction or dual-energy acquisition, single-photon emission CT (SPECT), magnetic resonance angiography (MRA), and magnetic resonance direct thrombus imaging (MRDTI). Furthermore, potential applications of AI are discussed.
Topics: Pulmonary Embolism; Humans; Acute Disease; Computed Tomography Angiography
PubMed: 38703584
DOI: 10.1016/j.thromres.2024.04.016 -
The British Journal of Radiology Dec 2023CT of the heart, in particular ECG-controlled coronary CT angiography (cCTA), has become clinical routine due to rapid technical progress with ever new generations of CT... (Review)
Review
CT of the heart, in particular ECG-controlled coronary CT angiography (cCTA), has become clinical routine due to rapid technical progress with ever new generations of CT equipment. Recently, CT scanners with photon-counting detectors (PCD) have been introduced which have the potential to address some of the remaining challenges for cardiac CT, such as limited spatial resolution and lack of high-quality spectral data. In this review article, we briefly discuss the technical principles of photon-counting detector CT, and we give an overview on how the improved spatial resolution of photon-counting detector CT and the routine availability of spectral data can benefit cardiac applications. We focus on coronary artery calcium scoring, cCTA, and on the evaluation of the myocardium.
Topics: Humans; Phantoms, Imaging; Tomography, X-Ray Computed; Heart; Coronary Angiography; Computed Tomography Angiography; Photons
PubMed: 37750856
DOI: 10.1259/bjr.20230407 -
The Journal of Clinical Investigation Jan 2024BACKGROUNDImproving and predicting tumor response to immunotherapy remains challenging. Combination therapy with a transforming growth factor-β receptor (TGF-βR)...
BACKGROUNDImproving and predicting tumor response to immunotherapy remains challenging. Combination therapy with a transforming growth factor-β receptor (TGF-βR) inhibitor that targets cancer-associated fibroblasts (CAFs) is promising for the enhancement of efficacy of immunotherapies. However, the effect of this approach in clinical trials is limited, requiring in vivo methods to better assess tumor responses to combination therapy.METHODSWe measured CAFs in vivo using the 68Ga-labeled fibroblast activation protein inhibitor-04 (68Ga-FAPI-04) for PET/CT imaging to guide the combination of TGF-β inhibition and immunotherapy. One hundred thirty-one patients with metastatic colorectal cancer (CRC) underwent 68Ga-FAPI and 18F-fluorodeoxyglucose (18F-FDG) PET/CT imaging. The relationship between uptake of 68Ga-FAPI and tumor immunity was analyzed in patients. Mouse cohorts of metastatic CRC were treated with the TGF-βR inhibitor combined with KN046, which blocks programmed death ligand 1 (PD-L1) and CTLA-4, followed by 68Ga-FAPI and 18F-FDG micro-PET/CT imaging to assess tumor responses.RESULTSPatients with metastatic CRC demonstrated high uptake rates of 68Ga-FAPI, along with suppressive tumor immunity and poor prognosis. The TGF-βR inhibitor enhanced tumor-infiltrating T cells and significantly sensitized metastatic CRC to KN046. 68Ga-FAPI PET/CT imaging accurately monitored the dynamic changes of CAFs and tumor response to combined the TGF-βR inhibitor with immunotherapy.CONCLUSION68Ga-FAPI PET/CT imaging is powerful in assessing tumor immunity and the response to immunotherapy in metastatic CRC. This study supports future clinical application of 68Ga-FAPI PET/CT to guide precise TGF-β inhibition plus immunotherapy in CRC patients, recommending 68Ga-FAPI and 18F-FDG dual PET/CT for CRC management.TRIAL REGISTRATIONCFFSTS Trial, ChiCTR2100053984, Chinese Clinical Trial Registry.FUNDINGNational Natural Science Foundation of China (82072695, 32270767, 82272035, 81972260).
Topics: Humans; Animals; Mice; Receptors, Transforming Growth Factor beta; Positron Emission Tomography Computed Tomography; Fluorodeoxyglucose F18; Positron-Emission Tomography; Colonic Neoplasms; Immunotherapy; Antibodies, Bispecific; Transforming Growth Factor beta; Quinolines
PubMed: 38175716
DOI: 10.1172/JCI170490 -
Cancer Imaging : the Official... Aug 2023F18-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) plays a crucial role in tumour diagnosis, staging, and therapy response evaluation... (Review)
Review
F18-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) plays a crucial role in tumour diagnosis, staging, and therapy response evaluation of various cancer types and has been a standard imaging modality used in clinical oncology practice for many years. However, it has certain limitations in evaluating some particular gastrointestinal cancer types due to low FDG-avidity or interphering physiological background activity. Fibroblast activation protein (FAP), a protein of the tumour microenvironment, is overexpressed in a wide range of cancers which makes it an attractive target for both tumour imaging and therapy. Recently, FAP-targeted radiopharmaceuticals are widely used in clinical research and achieved great results in tumour imaging. Considering the limitations of FDG PET/CT and the lack of physiological FAP-targeted tracer uptake in liver and intestinal loops, gastrointestinal cancers are among the most promising indications of FAP-targeted imaging. Herein, we present a comprehensive review of FAP-targeted imaging in gastrointestinal cancers in order to clarify the current and potential future role of this class of molecules in gastrointestinal oncology.
Topics: Humans; Positron Emission Tomography Computed Tomography; Fluorodeoxyglucose F18; Gastrointestinal Neoplasms; Positron-Emission Tomography; Liver; Tumor Microenvironment
PubMed: 37608378
DOI: 10.1186/s40644-023-00598-z