BACKGROUND: To evaluate and compare the diagnostic power of [18F]FLT-PET with ceMRI in patients with brain tumours or other focal lesions. METHODS: 121 patients with suspected brain tumour or those after brain tumour surgery were enroled in this retrospective study (61 females, 60 males, mean age 37.3 years, range 1-80 years). All patients underwent [18F]FLT-PET/MRI with gadolinium contrast agent application. In 118 of these patients, a final diagnosis was made, verified by histopathology or by follow-up. Agreement between ceMRI and [18F]FLT-PET of the whole study group was established. Further, sensitivity and specificity of ceMRI and [18F]FLT-PET were calculated for differentiation of high-grade vs. low-grade tumours, high-grade vs. low-grade tumours together with non-tumour lesions and for differentiation of high-grade tumours from all other verified lesions. RESULTS: [18F]FLT-PET and ceMRI findings were concordant in 119 cases (98%). On closer analysis of a subset of 64 patients with verified gliomas, the sensitivity and specificity of both PET and ceMRI were identical (90% and 84%, respectively) for differentiating low-grade from high-grade tumours, if the contrast enhancement and [18F]FLT uptake were considered as hallmarks of high-grade tumour. For differentiation of high-grade tumours from low-grade tumours and lesions of nontumorous aetiology (e.g., inflammatory lesions or post-therapeutic changes) in a subgroup of 93 patients by visual evaluation, the sensitivity of both PET and ceMRI was 90%, whereas the specificity of PET was slightly higher (61%) compared to ceMRI (57%). By receiver operating characteristic analysis, the sensitivity and specificity were 82% and 74%, respectively, when the threshold of SUVmax in the tumour was set to 0.9 g/ml. CONCLUSION: We demonstrated a generally very high correlation of [18F]FLT accumulation with contrast enhancement visible on ceMRI and a comparable diagnostic yield in both modalities for differentiating high-grade tumours from low-grade tumours and lesions of other aetiology.
- Klíčová slova
- Brain tumour, High grade, Low grade, PET/MRI, Tumour-like lesions, [18F]FLT,
- MeSH
- dideoxynukleosidy MeSH
- dítě MeSH
- dospělí MeSH
- gadolinium * farmakokinetika MeSH
- kojenec MeSH
- kontrastní látky MeSH
- lidé středního věku MeSH
- lidé MeSH
- magnetická rezonanční tomografie * metody MeSH
- mladiství MeSH
- mladý dospělý MeSH
- multimodální zobrazování metody MeSH
- nádory mozku * diagnostické zobrazování patologie metabolismus MeSH
- pozitronová emisní tomografie * metody MeSH
- předškolní dítě MeSH
- radiofarmaka MeSH
- retrospektivní studie MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- senzitivita a specificita MeSH
- Check Tag
- dítě MeSH
- dospělí MeSH
- kojenec MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- předškolní dítě MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- alovudine MeSH Prohlížeč
- dideoxynukleosidy MeSH
- gadolinium * MeSH
- kontrastní látky MeSH
- radiofarmaka MeSH
This article presents the protocol on Quality Controls in PET/CT and PET/MRI published online in May 2022 by the European Federation of Organisations for Medical Physics (EFOMP), which was developed by the Working group for PET/CT and PET/MRI Quality Control (QC) protocol. The main objective of this protocol was to comprehensively provide simple and practical procedures that may be integrated into clinical practice to identify changes in the PET/CT/MRI system's performance and avoid short- and long-term quality deterioration. The protocol describes the quality control procedures on radionuclide calibrators, weighing scales, PET, CT and MRI systems using selected and measurable parameters that are directly linked to clinical images quality. It helps to detect problems before they can impact clinical studies in terms of safety, image quality, quantification accuracy and patient radiation dose. CT and MRI QCs are described only in the context of their use for PET (attenuation correction and anatomical localization) imaging. Detailed step-by-step instructions have been provided, limiting any misinterpretations or interpersonal variations as much as possible. This paper presents the main characteristics of the protocol illustrated together with a brief summary of the content of each chapter. A regular QC based on the proposed protocol would guarantee that PET/CT and PET/MRI systems operate under optimal conditions, resulting in the best performance for routine clinical tasks.
Magnetic iron oxide nanocrystals (MIONs) are established as potent theranostic nanoplatforms due to their biocompatibility and the multifunctionality of their spin-active atomic framework. Recent insights have also unveiled their attractive near-infrared photothermal properties, which are, however, limited by their low near-infrared absorbance, resulting in noncompetitive photothermal conversion efficiencies (PCEs). Herein, we report on the dramatically improved photothermal conversion of condensed clustered MIONs, reaching an ultrahigh PCE of 71% at 808 nm, surpassing the so-far MION-based photothermal agents and even benchmark near-infrared photothermal nanomaterials. Moreover, their surface passivation is achieved through a simple self-assembly process, securing high colloidal stability and structural integrity in complex biological media. The bifunctional polymeric canopy simultaneously provided binding sites for anchoring additional cargo, such as a strong near-infrared-absorbing and fluorescent dye, enabling in vivo optical and photoacoustic imaging in deep tissues, while the iron oxide core ensures detection by magnetic resonance imaging. In vitro studies also highlighted a synergy-amplified photothermal effect that significantly reduces the viability of A549 cancer cells upon 808 nm laser irradiation. Integration of such-previously elusive-photophysical properties with simple and cost-effective nanoengineering through self-assembly represents a significant step toward sophisticated nanotheranostics, with great potential in the field of nanomedicine.
- Klíčová slova
- condensed clusters, iron oxides, multimodal imaging, noncovalent functionalization, photothermal agents,
- MeSH
- buňky A549 MeSH
- fotochemické procesy MeSH
- lidé MeSH
- magnetická rezonanční tomografie MeSH
- magnetické nanočástice chemie toxicita MeSH
- multimodální zobrazování metody MeSH
- myši MeSH
- optoakustické techniky metody MeSH
- teranostická nanomedicína metody MeSH
- viabilita buněk účinky léků MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- magnetické nanočástice MeSH
The imaging modality choice depends on the clinical question in hepatocellular carcinoma (HCC); when HCC is suspected, then ultrasound serves as imaging at the first line, followed by computed tomography. When specialized differential dia-gnosis or bio-logical behaviour of HCC is a clinical issue, magnetic resonance imaging with a use of hepatospecific contrast agent or hybrid imaging using positron emission tomography and computed tomography or positron emission tomography and magnetic resonance imaging with the application of 18F-fluorodeoxglucose or 18F-fluorocholine are exploited. In the therapy of HCC, it is possible to use locally destructive methods of interventional radiology, especially radiofrequency ablation or transarterial chemoembolization, or radioembolization, as the case may be.
- Klíčová slova
- computed tomography, hepatocellular carcinoma, hybrid imaging methods, magnetic resonance imaging, positron emission tomography,
- MeSH
- chirurgie s pomocí počítače metody MeSH
- hepatocelulární karcinom diagnostické zobrazování patologie chirurgie MeSH
- katetrizační ablace metody MeSH
- lidé MeSH
- multimodální zobrazování metody MeSH
- nádory jater patologie chirurgie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Hybrid imaging combining the beneficial properties of radioactivity and optical imaging within one imaging probe has gained increasing interest in radiopharmaceutical research. In this study, we modified the macrocyclic gallium-68 chelator fusarinine C (FSC) by conjugating a fluorescent moiety and tetrazine (Tz) moieties. The resulting hybrid imaging agents were used for pretargeting applications utilizing click reactions with a trans-cyclooctene (TCO) tagged targeting vector for a proof of principle both in vitro and in vivo. Starting from FSC, the fluorophores Sulfocyanine-5, Sulfocyanine-7, or IRDye800CW were conjugated, followed by introduction of one or two Tz motifs, resulting in mono and dimeric Tz conjugates. Evaluation included fluorescence microscopy, binding studies, logD, protein binding, in vivo biodistribution, µPET (micro-positron emission tomography), and optical imaging (OI) studies. 68Ga-labeled conjugates showed suitable hydrophilicity, high stability, and specific targeting properties towards Rituximab-TCO pre-treated CD20 expressing Raji cells. Biodistribution studies showed fast clearance and low accumulation in non-targeted organs for both SulfoCy5- and IRDye800CW-conjugates. In an alendronate-TCO based bone targeting model the dimeric IRDye800CW-conjugate resulted in specific targeting using PET and OI, superior to the monomer. This proof of concept study showed that the preparation of FSC-Tz hybrid imaging agents for pretargeting applications is feasible, making such compounds suitable for hybrid imaging applications.
- Klíčová slova
- PET, click chemistry, fluorescence, fusarinine C, gallium-68, optical imaging,
- MeSH
- fluorescenční protilátková technika MeSH
- kyseliny hydroxamové * chemie MeSH
- multimodální zobrazování * metody MeSH
- optické zobrazování metody MeSH
- ověření koncepční studie MeSH
- pozitronová emisní tomografie MeSH
- radiofarmaka * chemie MeSH
- radioizotopy galia MeSH
- radionuklidy MeSH
- syntetická chemie okamžité shody MeSH
- tkáňová distribuce MeSH
- železité sloučeniny * chemie MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- fusigen MeSH Prohlížeč
- Gallium-68 MeSH Prohlížeč
- kyseliny hydroxamové * MeSH
- radiofarmaka * MeSH
- radioizotopy galia MeSH
- radionuklidy MeSH
- železité sloučeniny * MeSH
BACKGROUND AND AIM: The availability of new treatments for metastatic castrate-resistant prostate cancer (mCRPC) patients increases the need for reliable biomarkers to help clinicians to choose the better sequence strategy. The aim of the present retrospective and observational work is to investigate the prognostic value of 18F-fluorocholine (18F-FCH) positron emission tomography (PET) parameters in mCRPC. MATERIALS AND METHODS: Between March 2013 and August 2016, 29 patients with mCRPC were included. They all received three-weekly docetaxel after androgen deprivation therapy, and they underwent 18F-FCH PET/computed tomography (CT) before and after the therapy. Semi-quantitative indices such as maximum standardized uptake value (SUVmax), mean standardized uptake value (SUVmean) with partial volume effect (PVC-SUV) correction, metabolically active tumour volume (MATV), and total lesion activity (TLA) with partial volume effect (PVC-TLA) correction were measured both in pre-treatment and post-treatment 18F-FCH PET/CT scans for each lesion. Whole-body indices were calculated as sum of values measured for each lesion (SSUVmax, SPVC-SUV, SMATV, and STLA). Progression-free survival (PFS) and overall survival (OS) were considered as clinical endpoints. Univariate and multivariate hazard ratios for whole-body 18F-FCH PET indices were performed, and p < 0.05 was considered as significant. RESULTS: Cox regression analysis showed a statistically significant correlation between PFS, SMATV, and STLA. No correlations between OS and 18F-FCH PET parameters were defined probably due to the small sample size. CONCLUSIONS: Semi-quantitative indices such as SMATV and STLA at baseline have a prognostic role in patients treated with docetaxel for mCRPC, suggesting a potential role of 18F-FCH PET/CT imaging in clinical decision-making.
- MeSH
- antagonisté androgenů aplikace a dávkování MeSH
- cholin aplikace a dávkování analogy a deriváty chemie MeSH
- doba přežití bez progrese choroby MeSH
- docetaxel aplikace a dávkování chemie MeSH
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- metastázy nádorů MeSH
- multimodální zobrazování metody MeSH
- nádory prostaty rezistentní na kastraci diagnostické zobrazování farmakoterapie patologie MeSH
- PET/CT metody MeSH
- prognóza MeSH
- radioisotopová scintigrafie metody MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- tumor burden účinky léků MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- antagonisté androgenů MeSH
- cholin MeSH
- docetaxel MeSH
- fluorocholine MeSH Prohlížeč
Fabry disease (FD) is a rare genetic X-linked disorder that can impact multiple organs. Cardiac involvement influences the prognosis of patients with FD, being one of the main causes of mortality. Cardiac imaging has proven essential in all aspects of Fabry cardiomyopathy evaluation, such as diagnosis (including detection of early organ changes), disease progression, and guideline for starting enzyme therapy. Imaging techniques used in cardiac evaluation of FD range from 2D and deformation studies in echocardiography to cardiac magnetic resonance (CMR), cardiac scintigraphy and positron emission tomography. The present review summarizes the imaging 'red flags' demonstrated to be able to differentiate early cardiac FD from normal controls and Fabry cardiomyopathy from other causes of hypertrophic cardiomyopathy. Also, it discusses the current evidence for the role of CMR in myocardial tissue characterization, as well as other imaging methods that have shown promise in FD. Current knowledge of the evaluation of the presence and extent of cardiac involvement at baseline and during follow-up of enzyme therapy efficiency are further presented. Multiple studies demonstrated that imaging parameters can be reliably used in establishing diagnosis and monitoring therapy in FD. Given the rarity of this disorder, we conclude that awareness should be raised about these imaging 'red flags' and likely patients sent for evaluation in expert centres.
- MeSH
- časná diagnóza MeSH
- echokardiografie metody MeSH
- Fabryho nemoc diagnostické zobrazování terapie MeSH
- interpretace obrazu počítačem * MeSH
- kardiologické zobrazovací techniky metody MeSH
- lidé MeSH
- magnetická rezonance kinematografická metody MeSH
- monitorování fyziologických funkcí metody MeSH
- multimodální zobrazování metody MeSH
- pozitronová emisní tomografie metody MeSH
- prognóza MeSH
- vzácné nemoci MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
PURPOSE: The purpose of this study was to evaluate a set of widely used nuclear medicine imaging agents as possible methods to study the early effects of systemic inflammation on the living brain in a mouse model of sepsis-associated encephalopathy (SAE). The lipopolysaccharide (LPS)-induced murine systemic inflammation model was selected as a model of SAE. PROCEDURES: C57BL/6 mice were used. A multimodal imaging protocol was carried out on each animal 4 h following the intravenous administration of LPS using the following tracers: [99mTc][2,2-dimethyl-3-[(3E)-3-oxidoiminobutan-2-yl]azanidylpropyl]-[(3E)-3-hydroxyiminobutan-2-yl]azanide ([99mTc]HMPAO) and ethyl-7-[125I]iodo-5-methyl-6-oxo-4H-imidazo[1,5-a][1,4]benzodiazepine-3-carboxylate ([125I]iomazenil) to measure brain perfusion and neuronal damage, respectively; 2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) to measure cerebral glucose uptake. We assessed microglia activity on another group of mice using 2-[6-chloro-2-(4-[125I]iodophenyl)-imidazo[1,2-a]pyridin-3-yl]-N-ethyl-N-methyl-acetamide ([125I]CLINME). Radiotracer uptakes were measured in different brain regions and correlated. Microglia activity was also assessed using immunohistochemistry. Brain glutathione levels were measured to investigate oxidative stress. RESULTS: Significantly reduced perfusion values and significantly enhanced [18F]FDG and [125I]CLINME uptake was measured in the LPS-treated group. Following perfusion compensation, enhanced [125I]iomazenil uptake was measured in the LPS-treated group's hippocampus and cerebellum. In this group, both [18F]FDG and [125I]iomazenil uptake showed highly negative correlation to perfusion measured with ([99mTc]HMPAO uptake in all brain regions. No significant differences were detected in brain glutathione levels between the groups. The CD45 and P2Y12 double-labeling immunohistochemistry showed widespread microglia activation in the LPS-treated group. CONCLUSIONS: Our results suggest that [125I]CLINME and [99mTc]HMPAO SPECT can be used to detect microglia activation and brain hypoperfusion, respectively, in the early phase (4 h post injection) of systemic inflammation. We suspect that the enhancement of [18F]FDG and [125I]iomazenil uptake in the LPS-treated group does not necessarily reflect neural hypermetabolism and the lack of neuronal damage. They are most likely caused by processes emerging during neuroinflammation, e.g., microglia activation and/or immune cell infiltration.
- Klíčová slova
- LPS, Microglia activation, Neuroinflammation, PET/MRI, SPECT/CT, Systemic infection, [125I]CLINME, [125I]iomazenil, [18F]FDG, [99mTc]HMPAO,
- MeSH
- fluorodeoxyglukosa F18 farmakokinetika MeSH
- glukosa metabolismus MeSH
- jednofotonová emisní výpočetní tomografie metody MeSH
- lipopolysacharidy MeSH
- modely nemocí na zvířatech MeSH
- mozek diagnostické zobrazování metabolismus MeSH
- multimodální zobrazování metody MeSH
- myši inbrední C57BL MeSH
- myši MeSH
- neurozobrazování metody MeSH
- nukleární lékařství metody MeSH
- pozitronová emisní tomografie metody MeSH
- radioaktivní indikátory * MeSH
- radioisotopová scintigrafie metody MeSH
- radioizotopy jodu farmakokinetika MeSH
- septická encefalopatie chemicky indukované diagnóza metabolismus patologie MeSH
- technecium 99mTc exametazim farmakokinetika MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
- práce podpořená grantem MeSH
- Názvy látek
- fluorodeoxyglukosa F18 MeSH
- glukosa MeSH
- Iodine-125 MeSH Prohlížeč
- lipopolysacharidy MeSH
- radioaktivní indikátory * MeSH
- radioizotopy jodu MeSH
- technecium 99mTc exametazim MeSH
AIM: To evaluate our own experience with 18F- fluoromethylcholine-(FCH)-positron-emission tomography combined with magnetic resonance imaging (PET/MRI) in restaging of patients with prostatic carcinoma and elevated serum prostate-specific antigen (PSA) level. PATIENTS AND METHODS: The analysis was performed on a sample of 100 male patients who underwent 18F-FCH-PET/MRI, with a mean age of 63.2 years (range=47-78 years). The imaging was performed using an integrated PET/MRI hybrid system after intravenous application of 18F-FCH at a dose of 1.25 MBq/kg. The number and sites of pathological accumulation of FCH related to local recurrence, nodal spread and skeletal metastases were compared to corresponding MRI findings; furthermore, the relation of PSA level and presence of FCH accumulation in tumorous tissue was assessed; finally we correlated the findings of different sites of metastatic involvement. RESULTS: In patients with a PSA level up to 2 ng/ml, accumulation in tumorous tissue of local recurrence or metastases was found in 83.33% in cases of biochemical relapse, and in patients with PSA level above 5 ng/ml in 100% of cases. In general, we found any finding explained rise of PSA level in 94% of patients. CONCLUSION: 18F-FCH-PET/MRI using an integrated system with 1,25 MBq/kg dosing of FCH is a valuable tool in evaluation of restaging in patients with prostatic carcinoma, with high detection rate even in those with a low serum PSA level.
- Klíčová slova
- PET/MRI, PSA, Prostatic carcinoma, fluoromethylcholine, restaging,
- MeSH
- adenokarcinom diagnostické zobrazování patologie MeSH
- cholin analogy a deriváty MeSH
- lidé středního věku MeSH
- lidé MeSH
- magnetická rezonanční tomografie metody MeSH
- multimodální zobrazování metody MeSH
- nádory prostaty diagnostické zobrazování patologie MeSH
- pozitronová emisní tomografie metody MeSH
- prostatický specifický antigen MeSH
- radiofarmaka MeSH
- radioizotopy fluoru MeSH
- senioři MeSH
- staging nádorů metody MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- cholin MeSH
- fluorocholine MeSH Prohlížeč
- prostatický specifický antigen MeSH
- radiofarmaka MeSH
- radioizotopy fluoru MeSH
- MeSH
- echokardiografie metody MeSH
- endomyokardiální fibróza komplikace diagnostické zobrazování chirurgie MeSH
- Hodgkinova nemoc komplikace diagnóza MeSH
- hodnocení rizik MeSH
- lidé středního věku MeSH
- lidé MeSH
- lymfatické uzliny chirurgie MeSH
- multimodální zobrazování metody MeSH
- následné studie MeSH
- pozitronová emisní tomografie metody MeSH
- srdeční selhání diagnostické zobrazování etiologie terapie MeSH
- výsledek terapie MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- kazuistiky MeSH
