Brain 18 F-FDG PET reveals cortico-subcortical hypermetabolic dysfunction in juvenile neuropsychiatric systemic lupus erythematosus.

Background: In juvenile systemic lupus erythematosus (j-SLE) with neuropsychiatric (NP) symptoms, there is a lack of diagnostic biomarkers. Thus, we study whether PET-FDG may identify any metabolic dysfunction in j-NPSLE.

Methods: A total of 19 FDG-PET exams were consecutively performed using PET-MRI system in 11 non-sedated patients presenting with j-NPSLE (11-18y) for less than 18 months (m) and without any significant lesion at MRI.

Local and distant response to intratumoral immunotherapy assessed by immunoPET in mice.

Background: Despite the promising efficacy of immune checkpoint blockers (ICB), tumor resistance and immune-related adverse events hinder their success in cancer treatment. To address these challenges, intratumoral delivery of immunotherapies has emerged as a potential solution, aiming to mitigate side effects through reduced systemic exposure while increasing effectiveness by enhancing local bioavailability. However, a comprehensive understanding of the local and systemic distribution of ICBs following intratumoral administration, as well as their impact on distant tumors, remains crucial for optimizing their therapeutic potential.

Relevance of F-DOPA visual and semi-quantitative PET metrics for the diagnostic of Parkinson disease in clinical practice: a machine learning-based inference study.

Purpose: To decipher the relevance of visual and semi-quantitative 6-fluoro-(18F)-L-DOPA (F-DOPA) interpretation methods for the diagnostic of idiopathic Parkinson disease (IPD) in hybrid positron emission tomography (PET) and magnetic resonance imaging.

Material And Methods: A total of 110 consecutive patients (48 IPD and 62 controls) with 11 months of median clinical follow-up (reference standard) were included. A composite visual assessment from five independent nuclear imaging readers, together with striatal standard uptake value (SUV) to occipital SUV ratio, striatal gradients and putamen asymmetry-based semi-quantitative PET metrics automatically extracted used to train machine learning models to classify IPD versus controls.

Head-to-Head Comparison Between Rabbit Sign and EANM/SNMMI Criteria for the 18F-DOPA Visual Assessment of Parkinsonian Syndromes in PET/MRI: A Multiple Expert-Based and Blinded Controlled Study.

Purpose: The aim of this study was to compare the diagnostic performance of the rabbit visual pattern versus the one endorsed by the EANM/SNMMI for the diagnosis of parkinsonian syndromes in PET/MRI.

Patients And Methods: The 18F-DOPA PET images of 129 consecutive patients (65 Park+ and 64 controls) with 1 year of clinical follow-up were reviewed independently by 5 experienced readers on the same imaging workstation, blinded to the final clinical diagnosis. Two visual methods were assessed independently, with several days to months of interval: the criteria endorsed by EANM/SNMMI and the "rabbit" shape of the striate assessed on 3D MIP images.

[C]glyburide PET imaging for quantitative determination of the importance of Organic Anion-Transporting Polypeptide transporter function in the human liver and whole-body.

Organic Anion-Transporting Polypeptides (OATPs) are known to control the liver uptake of many drugs. Non-hepatic expression of OATPs has been reported although functional importance for whole-body pharmacokinetics (WBPK) remains unknown. Glyburide is a well described substrate of several hepatic and non-hepatic OATPs.

Optimizing Immuno-PET Imaging of Tumor PD-L1 Expression: Pharmacokinetic, Biodistribution, and Dosimetric Comparisons of Zr-Labeled Anti-PD-L1 Antibody Formats.

PET imaging of programmed cell death ligand 1 (PD-L1) may help to noninvasively predict and monitor responses to anti-programmed cell death 1/anti-PD-L1 immunotherapies. In this study, we compared the imaging characteristics of 3 radioligands derived from the anti-PD-L1 IgG1 complement 4 (C4). In addition to the IgG C4, we produced a fragment antigen-binding (Fab) C4, as well as a double-mutant IgG C4 (H310A/H435Q) with minimal affinity for the murine neonatal Fc receptor.

F-FDG PET/MR in focal epilepsy: A new step for improving the detection of epileptogenic lesions.

Purpose: Hybrid PET/MR is a promising tool in focal drug-resistant epilepsy, however the additional value for the detection of epileptogenic lesions and surgical decision-making remains to be established.

Methods: We retrospectively compared F-FDG PET/MR images with those obtained by a previous F-FDG PET co-registered with MRI (PET+MR) in 25 consecutive patients (16 females, 13-60 years) investigated for focal drug-resistant epilepsy. Visual analysis was performed by two readers blinded from imaging modalities, asked to assess the technical characteristics (co-registration, quality of images), the confidence in results, the location of PET abnormalities and the presence of a structural lesion on MRI.

Fully Integrated Quantitative Multiparametric Analysis of Non-Small Cell Lung Cancer at 3-T PET/MRI: Toward One-Stop-Shop Tumor Biological Characterization at the Supervoxel Level.

Introduction: The aim of this study was to study the feasibility of a fully integrated multiparametric imaging framework to characterize non-small cell lung cancer (NSCLC) at 3-T PET/MRI.

Patients And Methods: An 18F-FDG PET/MRI multiparametric imaging framework was developed and prospectively applied to 11 biopsy-proven NSCLC patients. For each tumor, 12 parametric maps were generated, including PET full kinetic modeling, apparent diffusion coefficient, T1/T2 relaxation times, and DCE full kinetic modeling.

PET imaging of immune checkpoint proteins in oncology.

Despite the remarkable clinical successes of immune checkpoint inhibitors (ICIs) in various advanced cancers, response is still limited to a subset of patients that generally exhibit tumoral expression of immune checkpoint (IC) proteins. Development of biomarkers assessing the expression of such ICs is therefore a major challenge nowadays to refine patient selection and improve therapeutic benefits. Positron emission tomography (PET) imaging using IC-targeted radiolabeled monoclonal antibodies (immunoPET) provides a non-invasive and whole-body visualization of in vivo IC biodistribution.

Challenges and Perspectives of the Hybridization of PET with Functional MRI or Ultrasound for Neuroimaging.

Hybridization of positron emission tomography (PET) with other functional neuroimaging techniques such as functional magnetic resonance imaging (fMRI) or functional ultrasound (fUS) still raises technical and methodological challenges. Beyond the co-registration of anatomical images with functional data, development of hybrid imaging systems has paved the way for a large field of research based on the concept of bimodal functional neuroimaging such as PET/fMRI. In this framework, comparison of respective performances of brain PET and fUS suggests complementarity and great potential of hybrid PET/fUS for preclinical neuroimaging.

F-FDG PET and DCE kinetic modeling and their correlations in primary NSCLC: first voxel-wise correlative analysis of human simultaneous [18F]FDG PET-MRI data.

Objectives: To decipher the correlations between PET and DCE kinetic parameters in non-small-cell lung cancer (NSCLC), by using voxel-wise analysis of dynamic simultaneous [18F]FDG PET-MRI.

Material And Methods: Fourteen treatment-naïve patients with biopsy-proven NSCLC prospectively underwent a 1-h dynamic [18F]FDG thoracic PET-MRI scan including DCE. The PET and DCE data were normalized to their corresponding T-weighted MR morphological space, and tumors were masked semi-automatically.

Diffusion-weighted Imaging Voxelwise-matched Analyses of Lung Cancer at 3.0-T PET/MRI: Reverse Phase Encoding Approach for Echo-planar Imaging Distortion Correction.

Background PET/MRI has drawn increasing interest in thoracic oncology due to the simultaneous acquisition of PET and MRI data. Geometric distortions related to diffusion-weighted imaging (DWI) limit the evaluation of voxelwise multimodal analyses. Purpose To assess the effectiveness of reverse phase encoding in correcting DWI geometric distortion for multimodal PET/MRI voxelwise lung tumor analyses.

Correction to: F-FDG PET in drug-resistant epilepsy due to focal cortical dysplasia type 2: additional value of electroclinical data and coregistration with MRI.

The original version of this article has added numbers in the text which are unnecessary. Correct line should be: "We also performed PET/MRI based surgical resections in an increasing number of MRI negative/ doubtful cases with favourable outcome."

F-FDG PET in drug-resistant epilepsy due to focal cortical dysplasia type 2: additional value of electroclinical data and coregistration with MRI.

Purpose: To assess the localizing value of F-FDG PET in patients operated on for drug-resistant epilepsy due to focal cortical dysplasia type 2 (FCD).

Methods: We analysed F-FDG PET scans from 103 consecutive patients (52 males, 7-65 years old) with histologically proven FCD. PET and MRI data were first reviewed by visual analysis blinded to clinical information and FCD location.

Cross-sectional variations of white and grey matter in older hypertensive patients with subjective memory complaints.

Mild cognitive impairment and Alzheimer's dementia involve a grey matter disease, quantifiable by F-Fluorodeoxyglucose positron emission tomography (FDG-PET), but also white matter damage, evidenced by diffusion tensor magnetic resonance imaging (DTI), which may play an additional pathogenic role. This study aimed to determine whether such DTI and PET variations are also interrelated in a high-risk population of older hypertensive patients with only subjective memory complaints (SMC). Sixty older hypertensive patients (75 ± 5 years) with SMC were referred to DTI and FDG-PET brain imaging, executive and memory tests, as well as peripheral and central blood pressure (BP) measurements.

Experimental transfusion of variant CJD-infected blood reveals previously uncharacterised prion disorder in mice and macaque.

Exposure of human populations to bovine spongiform encephalopathy through contaminated food has resulted in <250 cases of variant Creutzfeldt-Jakob disease (vCJD). However, more than 99% of vCJD infections could have remained silent suggesting a long-term risk of secondary transmission particularly through blood. Here, we present experimental evidence that transfusion in mice and non-human primates of blood products from symptomatic and non-symptomatic infected donors induces not only vCJD, but also a different class of neurological impairments.

Using P-MRI of hydroxyapatite for bone attenuation correction in PET-MRI: proof of concept in the rodent brain.

Background: The correction of γ-photon attenuation in PET-MRI remains a critical issue, especially for bone attenuation. This problem is of great importance for brain studies due to the density of the skull. Current techniques for skull attenuation correction (AC) provide indirect estimates of cortical bone density, leading to inaccurate estimates of brain activity.

Rate of Distant Metastases on 18F-FDG PET/CT at Initial Staging of Breast Cancer: Comparison of Women Younger and Older Than 40 Years.

Unlabelled: Women who have breast cancer and are younger than 40 y have a poorer outcome than older women. A higher rate of undetected metastases at the time of diagnosis in younger women has been proposed to account for this difference. Our main objective was to test this hypothesis by comparing the distant metastasis rate (DMR) on initial F-FDG PET/CT in a group of breast cancer patients younger than 40 y (<40 y group) with that in a group of breast cancer patients older than 40 y (≥40 y group).

Intracellular metabolites in the primate brain are primarily localized in long fibers rather than in cell bodies, as shown by diffusion-weighted magnetic resonance spectroscopy.

Due to their pure intracellular compartmentation, the translational diffusion of brain metabolites in vivo depends on the intracellular environment, including viscosity, molecular crowding and subcellular structures. However, as the diffusion time is increased, metabolites have enough time to significantly encounter cell boundaries, so that cell size and geometry are expected to strongly determine metabolite diffusion path. In the present work, diffusion-weighted nuclear magnetic resonance spectroscopy was used to investigate brain metabolite diffusion in vivo, at long and ultra-long diffusion times (from ~80 ms to more than 1 s), in a voxel with equal proportions of white and grey matter in macaque monkeys.

Mutations in SQSTM1 encoding p62 in amyotrophic lateral sclerosis: genetics and neuropathology.

Mutations in SQSTM1 encoding the sequestosome 1/p62 protein have recently been identified in familial and sporadic cases of amyotrophic lateral sclerosis (ALS). p62 is a component of the ubiquitin inclusions detected in degenerating neurons in ALS patients. We sequenced SQSTM1 in 90 French patients with familial ALS (FALS) and 74 autopsied ALS cases with sporadic ALS (SALS).

Anomalous diffusion of brain metabolites evidenced by diffusion-weighted magnetic resonance spectroscopy in vivo.

Translational displacement of molecules within cells is a key process in cellular biology. Molecular motion potentially depends on many factors, including active transport, cytosol viscosity and molecular crowding, tortuosity resulting from cytoskeleton and organelles, and restriction barriers. However, the relative contribution of these factors to molecular motion in the cytoplasm remains poorly understood.

Reactive astrocytes overexpress TSPO and are detected by TSPO positron emission tomography imaging.

Astrocytes and microglia become reactive under most brain pathological conditions, making this neuroinflammation process a surrogate marker of neuronal dysfunction. Neuroinflammation is associated with increased levels of translocator protein 18 kDa (TSPO) and binding sites for TSPO ligands. Positron emission tomography (PET) imaging of TSPO is thus commonly used to monitor neuroinflammation in preclinical and clinical studies.