PET Imaging in Cardiac Sarcoidosis: A Narrative Review with Focus on Novel PET Tracers

Sarcoidosis is a multi-system inflammatory disease characterized by the development of inflammation and noncaseating granulomas that can involve nearly every organ system, with a predilection for the pulmonary system. Cardiac involvement of sarcoidosis (CS) occurs in up to 70% of cases, and accounts for a significant share of sarcoid-related mortality. The clinical presentation of CS can range from absence of symptoms to conduction abnormalities, heart failure, arrhythmias, valvular disease, and sudden cardiac death. Given the significant morbidity and mortality associated with CS, timely diagnosis is important. Traditional imaging modalities and histologic evaluation by endomyocardial biopsy often provide a low diagnostic yield. Cardiac positron emission tomography (PET) has emerged as a leading advanced imaging modality for the diagnosis and management of CS. This review article will summarize several aspects of the current use of PET in CS, including indications for use, patient preparation, image acquisition and interpretation, diagnostic and prognostic performance, and evaluation of treatment response. Additionally, this review will discuss novel PET radiotracers currently under study or of potential interest in CS.

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A Gas Phase Route to [18F]fluoroform with Limited Molar Activity Dilution

Scientific Reports ◽

10.1038/s41598-019-50747-3 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 5

Author(s):

Bo Yeun Yang ◽

Sanjay Telu ◽

Mohammad B. Haskali ◽

Cheryl L. Morse ◽

Victor W. Pike

Keyword(s):

Gas Phase ◽

Imaging Modality ◽

Fluoride Ion ◽

Full Potential ◽

High Dilution ◽

New Approach ◽

Molar Activity ◽

Positron Emission ◽

Pet Radiotracers ◽

Trifluoromethyl Groups

Abstract Positron emission tomography (PET) is an important imaging modality for biomedical research and drug development. PET requires biochemically selective radiotracers to realize full potential. Fluorine-18 (t1/2 = 109.8 min) is a major radionuclide for labeling such radiotracers but is only readily available in high activities from cyclotrons as [18F]fluoride ion. [18F]fluoroform has emerged for labeling tracers in trifluoromethyl groups. Prior methods of [18F]fluoroform synthesis used difluoro precursors in solution and led to high dilution with carrier and low molar activity (Am). We explored a new approach for the synthesis of [18F]fluoroform based on the radiosynthesis of [18F]fluoromethane from [18F]fluoride ion and then cobaltIII fluoride mediated gas phase fluorination. We estimate that carrier dilution in this process is limited to about 3-fold and find that moderate to high Am values can be achieved. We show that [18F]fluoroform so produced is highly versatile for rapidly and efficiently labeling various chemotypes that carry trifluoromethyl groups, thereby expanding prospects for developing new PET radiotracers.

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Cardiac PET-CT: A Brief Review of Indications and Feasibility in the Indian Scenario

Indian Journal of Cardiovascular Disease in Women WINCARS ◽

10.1055/s-0040-1713688 ◽

2020 ◽

Vol 5 (02) ◽

pp. 129-136

Author(s):

Kavitha Nallapareddy ◽

V. L. Gowthami Rayaprolu

Keyword(s):

Single Photon ◽

Imaging Modality ◽

Photon Emission ◽

Myocardial Inflammation ◽

Emission Computed Tomography ◽

Cardiac Positron Emission Tomography ◽

Positron Emission ◽

Perfusion Agents ◽

Perfusion Assessment ◽

Positron Emitters

AbstractCardiac positron emission tomography (PET) is a functional imaging modality with the predominant indications being an assessment of myocardial perfusion and viability using short-lived positron emitters. PET procedures are used for perfusion assessment only when single-photon emission computed tomography is equivocal. Perfusion agents are ultra short-lived and have limited availability in our country, that is, only at centers with onsite cyclotron. Viability assessment with fluorodeoxyglucose (FDG) is widely performed in many centers across the country due to the availability of FDG. The other important indication is in the detection of inflammatory myocarditis, the most common being cardiac sarcoidosis done with special dietary instructions and FDG as a tracer. This indication is widely used for early detection of myocardial inflammation which would be reversible if treated early. It is also used in the assessment of treatment response. Newer tracer 68 Ga Dotapeptide is also used in this application.

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[18F]FDG positron emission tomography and ultrasound in the diagnosis of giant cell arteritis: congruent or complementary imaging methods?

Rheumatology ◽

10.1093/rheumatology/kez362 ◽

2019 ◽

Vol 59 (4) ◽

pp. 772-778 ◽

Cited By ~ 2

Author(s):

Stephan Imfeld ◽

Markus Aschwanden ◽

Christof Rottenburger ◽

Elke Schegk ◽

Christoph T Berger ◽

...

Keyword(s):

False Positive ◽

Vessel Wall ◽

Axillary Artery ◽

Diagnostic Yield ◽

Imaging Modality ◽

Temporal Artery ◽

Positron Emission ◽

Pet Ct ◽

Diagnostic Work ◽

Fdg Pet Ct

Abstract Objectives [18F]Fluorodeoxyglucose (FDG)-PET/CT and US are both well established for diagnosing GCA. The present study investigates their accuracy and whether they provide overlapping or complementary information in a cohort of patients presenting with suspicion of GCA. Methods We selected consecutive patients from our cohort of suspected GCA cases that underwent both extended vascular US and PET/CT for diagnostic work-up between December 2006 and August 2012. Results A total of 102 patients were included. Diagnosis of GCA was confirmed in 68 patients and excluded in 34 patients (controls). Vasculitic changes in US were most often found in the temporal artery with 32 positive findings on each side, followed by the popliteal artery (10 right, 9 left) and the subclavian/axillary artery (7 right, 8 left). By contrast, PET/CT showed vasculitis most frequently in the vertebral (23 right, 33 left) and common carotid arteries (32 right, 24 left), followed by the subclavian arteries (16 right, 18 left), and the thoracic (17) and abdominal aorta (23). In 37/68 GCA patients PET/CT and US both revealed vasculitic findings, 11/68 had positive findings in US only and 14/68 in PET/CT only. Specificity of US was higher (one false-positive vs five false-positive in PET/CT). On a single segment level, only 20 of 136 positive segments were positive in both imaging modalities. Conclusion PET/CT measuring vessel wall metabolism and US vessel wall morphology showed a comparable diagnostic accuracy for GCA. However PET/CT and US were often discrepant within single vascular regions. Thus PET/CT and US should be considered as complementary methods, with a second imaging modality increasing the diagnostic yield by 16–20%.

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Combined PET/MRI in brain glioma imaging

British Journal of Hospital Medicine ◽

10.12968/hmed.2019.80.7.380 ◽

2019 ◽

Vol 80 (7) ◽

pp. 380-386 ◽

Cited By ~ 1

Author(s):

Karar O Almansory ◽

Francesco Fraioli

Keyword(s):

Positron Emission Tomography ◽

Imaging Modality ◽

Disease Recurrence ◽

Emission Tomography ◽

Molecular Characteristics ◽

Low Grade ◽

Advantages And Disadvantages ◽

Primary Brain Tumours ◽

Positron Emission ◽

Pet Radiotracers

Gliomas are the most common primary brain tumours in children and adults, consisting of a heterogeneous group of neoplastic diseases arise from the supporting cells of the CNS (glial cells). Their histopathological and molecular characteristics vary considerably as do their management and prognosis. Conventional gadolinium-enhanced magnetic resonance imaging (MRI) is considered the primary imaging modality for initial work up and follow up of patients with gliomas, although it has some limitations, especially in differentiating high from low grade tumours and in distinguishing disease recurrence from post-therapy changes. Hybrid positron emission tomography (PET)/MRI is a relatively novel tool that combines MRI sequences with metabolic information from PET, and therefore different PET radiotracers, in a single scan. This article discusses the main advantages and disadvantages of combined PET/MRI compared to other conventional or more widely available imaging tools, such as MRI or combined positron emission tomography–computed tomography. The main uses of PET/MRI and the most commonly used PET radiotracers in providing diagnostic, prognostic and predictive information in patients with glioma are covered.

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FDG-PET/CT Assessment of Pulmonary Sarcoidosis: A Guide for Internists

Current Medical Imaging Formerly Current Medical Imaging Reviews ◽

10.2174/1573405614666180528101755 ◽

2018 ◽

Vol 15 (1) ◽

pp. 21-25 ◽

Cited By ~ 1

Author(s):

Marco Tana ◽

Silvio di Carlo ◽

Marcello Romano ◽

Massimo Alessandri ◽

Cosima Schiavone ◽

...

Keyword(s):

Computed Tomography ◽

Fdg Pet ◽

Correct Diagnosis ◽

Pulmonary Sarcoidosis ◽

High Resolution Computed Tomography ◽

Inflammatory Conditions ◽

Positron Emission ◽

Pet Ct ◽

Noncaseating Granulomas ◽

Fdg Pet Ct

Background:18F-fluorodeoxyglucose positron emission tomography integrated with computed tomography (18-F-FDG-PET/CT) is getting wide consensus in the diagnosis and staging of neoplastic disorders and represents a useful tool in the assessment of various inflammatory conditions. </P><P> Discussion: Sarcoidosis is an uncommon disease characterized by the systemic formation of noncaseating granulomas. Lungs are the sites most often affected, and investigation with high resolution computed tomography and biopsy is essential to achieve a correct diagnosis. 18-F-FDGPET/ CT is effective in the assessment of pulmonary sarcoidosis by demonstrating pulmonary and extrathoracic involvement and findings correlate well with pulmonary function in patients affected.Conclusion:This review would illustrate the usefulness and limits of 18-F-FDG-PET/CT in the assessment of pulmonary sarcoidosis.

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18F-Sodium Fluoride PET as a Diagnostic Modality for Metabolic, Autoimmune, and Osteogenic Bone Disorders: Cellular Mechanisms and Clinical Applications

International Journal of Molecular Sciences ◽

10.3390/ijms22126504 ◽

2021 ◽

Vol 22 (12) ◽

pp. 6504

Author(s):

Peter Sang Uk Park ◽

William Y. Raynor ◽

Yusha Sun ◽

Thomas J. Werner ◽

Chamith S. Rajapakse ◽

...

Keyword(s):

Sodium Fluoride ◽

Recent Literature ◽

Imaging Modality ◽

Bone Diseases ◽

Skeletal System ◽

Cellular Mechanisms ◽

Diagnostic Modality ◽

Bone Disorders ◽

Osteoblastic Activity ◽

Positron Emission

In a healthy body, homeostatic actions of osteoclasts and osteoblasts maintain the integrity of the skeletal system. When cellular activities of osteoclasts and osteoblasts become abnormal, pathological bone conditions, such as osteoporosis, can occur. Traditional imaging modalities, such as radiographs, are insensitive to the early cellular changes that precede gross pathological findings, often leading to delayed disease diagnoses and suboptimal therapeutic strategies. 18F-sodium fluoride (18F-NaF)-positron emission tomography (PET) is an emerging imaging modality with the potential for early diagnosis and monitoring of bone diseases through the detection of subtle metabolic changes. Specifically, the dissociated 18F- is incorporated into hydroxyapatite, and its uptake reflects osteoblastic activity and bone perfusion, allowing for the quantification of bone turnover. While 18F-NaF-PET has traditionally been used to detect metastatic bone disease, recent literature corroborates the use of 18F-NaF-PET in benign osseous conditions as well. In this review, we discuss the cellular mechanisms of 18F-NaF-PET and examine recent findings on its clinical application in diverse metabolic, autoimmune, and osteogenic bone disorders.

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Radiochemistry, Production Processes, Labeling Methods, and ImmunoPET Imaging Pharmaceuticals of Iodine-124

Molecules ◽

10.3390/molecules26020414 ◽

2021 ◽

Vol 26 (2) ◽

pp. 414

Author(s):

Krishan Kumar ◽

Arijit Ghosh

Keyword(s):

Physical Properties ◽

Imaging Modality ◽

Target Selection ◽

Positron Emission Tomography Imaging ◽

High Sensitivity ◽

High Specificity ◽

Production Processes ◽

Positron Emission ◽

Significant Research ◽

Clinical Environments

Target-specific biomolecules, monoclonal antibodies (mAb), proteins, and protein fragments are known to have high specificity and affinity for receptors associated with tumors and other pathological conditions. However, the large biomolecules have relatively intermediate to long circulation half-lives (>day) and tumor localization times. Combining superior target specificity of mAbs and high sensitivity and resolution of the PET (Positron Emission Tomography) imaging technique has created a paradigm-shifting imaging modality, ImmunoPET. In addition to metallic PET radionuclides, 124I is an attractive radionuclide for radiolabeling of mAbs as potential immunoPET imaging pharmaceuticals due to its physical properties (decay characteristics and half-life), easy and routine production by cyclotrons, and well-established methodologies for radioiodination. The objective of this report is to provide a comprehensive review of the physical properties of iodine and iodine radionuclides, production processes of 124I, various 124I-labeling methodologies for large biomolecules, mAbs, and the development of 124I-labeled immunoPET imaging pharmaceuticals for various cancer targets in preclinical and clinical environments. A summary of several production processes, including 123Te(d,n)124I, 124Te(d,2n)124I, 121Sb(α,n)124I, 123Sb(α,3n)124I, 123Sb(3He,2n)124I, natSb(α, xn)124I, natSb(3He,n)124I reactions, a detailed overview of the 124Te(p,n)124I reaction (including target selection, preparation, processing, and recovery of 124I), and a fully automated process that can be scaled up for GMP (Good Manufacturing Practices) production of large quantities of 124I is provided. Direct, using inorganic and organic oxidizing agents and enzyme catalysis, and indirect, using prosthetic groups, 124I-labeling techniques have been discussed. Significant research has been conducted, in more than the last two decades, in the development of 124I-labeled immunoPET imaging pharmaceuticals for target-specific cancer detection. Details of preclinical and clinical evaluations of the potential 124I-labeled immunoPET imaging pharmaceuticals are described here.

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Imaging modalities for cardiovascular phenotyping in asymptomatic people living with HIV

Vascular Medicine ◽

10.1177/1358863x20978702 ◽

2021 ◽

pp. 1358863X2097870

Author(s):

Maria Bonou ◽

Chris J Kapelios ◽

Eleni Athanasiadi ◽

Sophie I Mavrogeni ◽

Mina Psichogiou ◽

...

Keyword(s):

Cardiac Computed Tomography ◽

Imaging Modalities ◽

People Living With Hiv ◽

Cvd Risk ◽

Improve Risk Stratification ◽

Positron Emission ◽

Pet Ct ◽

Living With Hiv ◽

Subclinical Cvd ◽

Related Mortality

Cardiovascular disease (CVD) has emerged as a leading cause of non-HIV-related mortality among people living with HIV (PLWH). Despite the growing CVD burden in PLWH, there is concern that general population risk score models may underestimate CVD risk in these patients. Imaging modalities have received mounting attention lately to better understand the pathophysiology of subclinical CVD and provide improved risk assessment in this population. To date, traditional and well-established techniques such as echocardiography, pulse wave velocity, and carotid intima thickness continue to be the basis for the diagnosis and subsequent monitoring of vascular atherosclerosis and heart failure. Furthermore, novel imaging tools such as cardiac computed tomography (CT) and cardiac CT angiography (CCTA), positron emission tomography/CT (PET/CT), and cardiac magnetic resonance (CMR) have provided new insights into accelerated cardiovascular abnormalities in PLWH and are currently evaluated with regards to their potential to improve risk stratification.

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Value of PET imaging for radiation therapy

Nuklearmedizin ◽

10.1055/a-1525-7029 ◽

2021 ◽

Author(s):

Constantin Lapa ◽

Ursula Nestle ◽

Nathalie L. Albert ◽

Christian Baues ◽

Ambros Beer ◽

...

Keyword(s):

Radiation Treatment ◽

Imaging Modality ◽

Tumour Response ◽

Emission Tomography ◽

Current Status ◽

Response Monitoring ◽

Radiation Treatment Planning ◽

Policy Makers ◽

Comprehensive Review ◽

Positron Emission

AbstractThis comprehensive review written by experts in their field gives an overview on the current status of incorporating positron emission tomography (PET) into radiation treatment planning. Moreover, it highlights ongoing studies for treatment individualisation and per-treatment tumour response monitoring for various primary tumours. Novel tracers and image analysis methods are discussed. The authors believe this contribution to be of crucial value for experts in the field as well as for policy makers deciding on the reimbursement of this powerful imaging modality.

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In Vivo Imaging of Biodegradable Implants and Related Tissue Biomarkers

Polymers ◽

10.3390/polym13142348 ◽

2021 ◽

Vol 13 (14) ◽

pp. 2348

Author(s):

Leon Riehakainen ◽

Chiara Cavallini ◽

Paolo Armanetti ◽

Daniele Panetta ◽

Davide Caramella ◽

...

Keyword(s):

Imaging Modality ◽

Imaging Techniques ◽

Special Focus ◽

Tissue Remodelling ◽

Biodegradable Implant ◽

Advantages And Disadvantages ◽

Non Invasive ◽

Positron Emission ◽

Longitudinal Imaging

Non-invasive longitudinal imaging of osseointegration of bone implants is essential to ensure a comprehensive, physical and biochemical understanding of the processes related to a successful implant integration and its long-term clinical outcome. This study critically reviews the present imaging techniques that may play a role to assess the initial stability, bone quality and quantity, associated tissue remodelling dependent on implanted material, implantation site (surrounding tissues and placement depth), and biomarkers that may be targeted. An updated list of biodegradable implant materials that have been reported in the literature, from metal, polymer and ceramic categories, is provided with reference to the use of specific imaging modalities (computed tomography, positron emission tomography, ultrasound, photoacoustic and magnetic resonance imaging) suitable for longitudinal and non-invasive imaging in humans. The advantages and disadvantages of the single imaging modality are discussed with a special focus on preclinical imaging for biodegradable implant research. Indeed, the investigation of a new implant commonly requires histological examination, which is invasive and does not allow longitudinal studies, thus requiring a large number of animals for preclinical testing. For this reason, an update of the multimodal and multi-parametric imaging capabilities will be here presented with a specific focus on modern biomaterial research.

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