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- Eriksson, Olof, et al.
(författare)
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Imaging the islet graft by positron emission tomography
- 2012
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Ingår i: European Journal of Nuclear Medicine and Molecular Imaging. - : Springer Science and Business Media LLC. - 1619-7070 .- 1619-7089. ; 39:3, s. 533-542
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Forskningsöversikt (refereegranskat)abstract
- Clinical islet transplantation is being investigated as a permanent cure for type 1 diabetes mellitus (T1DM). Currently, intraportal infusion of islets is the favoured procedure, but several novel implantation sites have been suggested. Noninvasive longitudinal methodologies are an increasingly important tool for assessing the fate of transplanted islets, their mass, function and early signs of rejection. This article reviews the approaches available for islet graft imaging by positron emission tomography and progress in the field, as well as future challenges and opportunities.
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| 3. |
- Eriksson, Olof, et al.
(författare)
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On the use of [F-18]DOPA as an imaging biomarker for transplanted islet mass
- 2014
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Ingår i: Annals of Nuclear Medicine. - : Springer Science and Business Media LLC. - 0914-7187 .- 1864-6433. ; 28:1, s. 47-52
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Tidskriftsartikel (refereegranskat)abstract
- AimIslet transplantation is being developed as a potential cure for patients with type 1 diabetes. There is a need for non-invasive imaging techniques for the quantification of transplanted islets, as current transplantation sites are associated with a substantial loss of islet viability. The dopaminergic metabolic pathway is present in the islets; therefore, we propose Fluorine-18 labeled l-3,4-dihydroxyphenylalanine ([F-18]DOPA) as a biomarker for transplanted islet mass.MethodsThe expression of enzymes involved in the dopaminergic metabolic pathway was investigated in both native and transplanted human islets. The specific uptake of [F-18]DOPA in islets and immortalized beta cells was studied in vitro by selective blocking of dopa decarboxylase (DDC). Initial in vivo PET imaging of viable subcutaneous human islets was performed using [F-18]DOPA.ResultsDDC and vesicular monoamine transporter 2 are co-localized with insulin in the native human pancreas, and the expression is retained after transplantation. Islet uptake of the [F-18]DOPA could be modulated by inhibiting DDC, indicating that the uptake followed the normal dopaminergic metabolic pathway. In vivo imaging revealed [F-18]DOPA uptake at the site of the functional islet graft. Based on the in vitro and in vivo results presented in this study, we propose to further validate [F-18]DOPA-PET as a sensitive imaging modality for imaging extrahepatically transplanted islets.
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| 4. |
- Kepe, Vladimir, et al.
(författare)
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Amyloid-beta Positron Emission Tomography Imaging Probes : A Critical Review
- 2013
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Ingår i: Journal of Alzheimer's Disease. - 1387-2877 .- 1875-8908. ; 36:4, s. 613-631
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Forskningsöversikt (refereegranskat)abstract
- The rapidly rising prevalence and cost of Alzheimer's disease in recent decades has made the imaging of amyloid-beta deposits the focus of intense research. Several amyloid imaging probes with purported specificity for amyloid-beta plaques are currently at various stages of FDA approval. However, a number of factors appear to preclude these probes from clinical utilization. As the available "amyloid specific" positron emission tomography imaging probes have failed to demonstrate diagnostic value and have shown limited utility for monitoring therapeutic interventions in humans, a debate on their significance has emerged. The aim of this review is to identify and discuss critically the scientific issues contributing to the extensive inconsistencies reported in the literature on their purported in vivo amyloid specificity and potential utilization in patients.
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| 5. |
- Muser, Daniele, et al.
(författare)
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Risk Stratification of Patients With Apparently Idiopathic Premature Ventricular Contractions A Multicenter International CMR Registry
- 2020
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Ingår i: JACC. - : ELSEVIER. - 2405-500X .- 2405-5018. ; 6:6, s. 722-735
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES This study investigated the prevalence and prognostic significance of concealed myocardial abnormalities identified by cardiac magnetic resonance (CMR) imaging in patients with apparently idiopathic premature ventricular contractions (PVCs). BACKGROUND The rote of CMR imaging in patients with frequent PVCs and otherwise negative diagnostic workup is uncertain. METHODS This was a multicenter, international study that included 518 patients (age 44 +/- 15 years; 57% men) with frequent (>1,000/24 h) PVCs and negative routine diagnostic workup. Patients underwent a comprehensive CMR protocol including late gadolinium enhancement imaging for detection of necrosis and/or fibrosis. The study endpoint was a composite of sudden cardiac death, resuscitated cardiac arrest, and nonfatal episodes of ventricular fibrillation or sustained ventricular tachycardia that required appropriate implantable cardioverter-defibrillator therapy. RESULTS Myocardial abnormalities were found in 85 (16%) patients. Mate gender (odds ratio [OR]: 4.28; 95% confidence interval [CI]: 2.06 to 8.93; p = 0.01), family history of sudden cardiac death and/or cardiomyopathy (OR: 3.61; 95% CI: 1.33 to 9.82; p = 0.01), multifocat PVCs (OR: 11.12; 95% CI: 4.35 to 28.46; p < 0.01), and non-left bundle branch block inferior axis morphology (OR: 14.11; 95% CI: 7.35 to 27.07; p < 0.01) were alt significantly related to the presence of myocardial abnormalities. After a median follow-up of 67 months, the composite endpoint occurred in 26 (5%) patients. Subjects with myocardial abnormalities on CMR had a higher incidence of the composite outcome (n = 25; 29%) compared with those without abnormalities (n = 1; 0.2%; p < 0.01). CONCLUSIONS CMR can identify concealed myocardial abnormalities in 16% of patients with apparently idiopathic frequent PVCs. Presence of myocardial abnormalities on CMR predict worse clinical outcomes. (C) 2019 by the American College of Cardiology Foundation.
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- Saboury, Babak, et al.
(författare)
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Alavi–carlsen calcification score (Accs): A simple measure of global cardiac atherosclerosis burden
- 2021
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Ingår i: Diagnostics. - : MDPI AG. - 2075-4418. ; 11:8
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Tidskriftsartikel (refereegranskat)abstract
- Multislice cardiac CT characterizes late stage macrocalcification in epicardial arteries as op-posed to PET/CT, which mirrors early phase arterial wall changes in epicardial and transmural coronary arteries. With regard to tracer, there has been a shift from using mainly18 F-fluorodeoxyglucose (FDG), indicating inflammation, to applying predominantly18 F-sodium fluoride (NaF) due to its high affinity for arterial wall microcalcification and more consistent association with cardiovascular risk factors. To make NaF-PET/CT an indispensable adjunct to clinical assessment of cardiac atherosclerosis, the Alavi–Carlsen Calcification Score (ACCS) has been proposed. It constitutes a global assessment of cardiac atherosclerosis burden in the individual patient, supported by an artificial intelligence (AI)-based approach for fast observer-independent segmentation. Common measures for characterizing epicardial coronary atherosclerosis by NaF-PET/CT as the maximum standardized uptake value (SUV) or target-to-background ratio are more versatile, error prone, and less reproducible than the ACCS, which equals the average cardiac SUV. The AI-based approach ensures a quick and easy delineation of the entire heart in 3D to obtain the ACCS expressing ongoing global cardiac atherosclerosis, even before it gives rise to CT-detectable coronary calcification. The quantification of global cardiac atherosclerotic burden by the ACCS is suited for management triage and monitoring of disease progression with and without intervention.
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