A5042553961- Medical Imaging Techniques and Applications
- Advanced X-ray and CT Imaging
- Radiation Detection and Scintillator Technologies
- Radiation Dose and Imaging
- Advanced Radiotherapy Techniques
- Radiomics and Machine Learning in Medical Imaging
- Advanced MRI Techniques and Applications
- Atomic and Subatomic Physics Research
- Long-Term Effects of COVID-19
- COVID-19 Clinical Research Studies
- Nuclear Physics and Applications
- Cardiac Structural Anomalies and Repair
- Radiopharmaceutical Chemistry and Applications
- Cancer Immunotherapy and Biomarkers
- Signaling Pathways in Disease
- Peptidase Inhibition and Analysis
- Immunotherapy and Immune Responses
- Immune cells in cancer
- Lung Cancer Treatments and Mutations
- Spondyloarthritis Studies and Treatments
- Medical Imaging and Pathology Studies
- Lanthanide and Transition Metal Complexes
- Glioma Diagnosis and Treatment
- Digital Radiography and Breast Imaging
- Cardiac Fibrosis and Remodeling
University of California, Davis
2020-2025
Klinikum rechts der Isar
2015-2022
Technical University of Munich
2015-2022
Philips (Germany)
2012-2015
RWTH Aachen University
2015
Philips (Finland)
2013
The world’s first total-body PET scanner with an axial field of view (AFOV) 194 cm is now in clinical and research use at our institution. uEXPLORER PET/CT system the commercially available scanner. Here we present a detailed physical characterization this based on National Electrical Manufacturers Association (NEMA) NU 2-2018 along new set measurements devised to appropriately characterize AFOV. <b>Methods:</b> Sensitivity, count-rate performance, time-of-flight resolution, spatial image...
Heart failure remains a major source of late morbidity and mortality after myocardial infarction (MI). The temporospatial presence activated fibroblasts in the injured myocardium predicts quality cardiac remodeling MI. Therefore, monitoring is great interest for studying Fibroblast activation protein (FAP) expression upregulated fibroblasts. This study investigated feasibility imaging with new <sup>68</sup>Ga-labeled FAP inhibitor (<sup>68</sup>Ga-FAPI-04) PET fibroblast preclinical model...
The collaboration of Yale, the University California, Davis, and United Imaging Healthcare has successfully developed NeuroEXPLORER, a dedicated human brain PET imager with high spatial resolution, sensitivity, built-in 3-dimensional camera for markerless continuous motion tracking. It depth-of-interaction time-of-flight resolutions, along 52.4-cm transverse field view (FOV) an extended axial FOV (49.5 cm) to enhance sensitivity. Here, we present physical characterization, performance...
With most of the T cells residing in tissue, not blood, developing noninvasive methods for vivo quantification their biodistribution and kinetics is important studying role immune response memory. This study presents first use dynamic positron emission tomography (PET) kinetic modeling measurement CD8
Our aim was to define a lower limit of reduced injected activity in delayed [
Immunotherapies, especially checkpoint inhibitors such as anti–programmed cell death protein 1 (anti–PD-1) antibodies, have transformed cancer treatment by enhancing the immune system's capability to target and kill cells. However, predicting immunotherapy response remains challenging. <sup>18</sup>F-arabinosyl guanine ([<sup>18</sup>F]F-AraG) is a molecular imaging tracer targeting activated T cells, which may facilitate therapy assessment noninvasive quantification of activity within tumor...
MADPET4 is the first small animal PET insert with two layers of individually read out crystals in combination silicon photomultiplier technology. It has a novel detector arrangement, which all face center field view transaxially. In this work, performance was evaluated and compared to other preclinical scanners using NEMA NU 4 measurements, followed by imaging mouse-size hot-rod resolution phantom vivo simultaneous PET/MRI scans 7 T MRI scanner. The had peak sensitivity 0.49%, an energy...
Autoimmune inflammatory arthritides (AIA), such as psoriatic arthritis and rheumatoid arthritis, are chronic systemic conditions that affect multiple joints of the body. Recently, total-body (TB) PET/CT scanners exhibiting superior technical characteristics (total-body coverage, geometric sensitivity) could benefit AIA evaluation, compared with conventional systems, have become available. The objectives this work were to assess performance an ultra-low-dose, 18F-FDG TB acquisition protocol...
Absolute quantification of regional tissue concentration radioactivity in positron emission tomography (PET) is a critical parameter-of-interest across various clinical and research applications affected by complex interplay factors including scanner calibration, data corrections, image reconstruction. The emergence long axial field-of-view (FOV) PET systems widens the dynamic range accessible to creates new opportunities reducing scan time radiation dose, delayed or low imaging, as well...
Abstract Objective. This study presents and evaluates a robust Monte Carlo-based scatter correction (SC) method for long axial field of view (FOV) total-body positron emission tomography (PET) using the uEXPLORER PET/CT scanner. Approach. Our algorithm utilizes Carlo (MC) tool SimSET to compute SC factors in between individual image reconstruction iterations within our in-house list-mode time-of-flight-based framework. We also introduced unique scaling technique at detector block-level...
Transarterial radioembolization (TARE) is a locoregional radiopharmaceutical therapy based on the delivery of radioactive 90Y microspheres to liver tumors. The importance personalized dosimetry make TARE safer and more effective has been demonstrated in recent clinical studies, stressing need for quantification dose-response relationship ultimately optimize administered activity before treatment image it after treatment. dosimetric studies are challenging because lack accurate precise...
The current generation of total-body positron emission tomography (PET) scanners offer significant sensitivity increase with an extended axial imaging extent. With the large volume lutetium-based scintillation crystals that are used as detector elements in these scanners, there is increased flux background radiation originating from 176Lu decay and higher for detecting it. Combined ability scanning entire body a single bed position, this allows more effective utilization lutetium...
Wound healing after myocardial infarction (MI) is a dynamic and complex multiple phase process, coordinated cellular response required for proper scar formation. The current paradigm suggests that pro-inflammatory monocytes infiltrate the MI zone during initial differentiate into inflammatory macrophages, then switch their phenotypes to anti-inflammatory reparative phase. Visualization of post-MI great interest because it may reveal delayed resolution inflammation, which in turn predicts...
Conventional whole-body static <sup>18</sup>F-FDG PET imaging provides a semiquantitative evaluation of overall glucose metabolism without insight into the specific transport and metabolic steps. Here we demonstrate ability total-body multiparametric to quantitatively evaluate using macroparametric quantification assess delivery phosphorylation processes microparametric for studying recovery from coronavirus disease 2019 (COVID-19). <b>Methods:</b> The study included 13 healthy subjects 12...
Compromises in the design of a positron emission tomography (PET) insert for magnetic resonance imaging (MRI) system should minimize deterioration image quality both modalities, particularly when simultaneous demanding acquisitions are performed. In this work, advantages using individually read-out crystals with high-gain silicon photomultipliers (SiPMs) were studied small animal PET 7 T MRI system, which SiPM charge was transferred to outside scanner coaxial cables. The interferences...
With the majority of CD8+ T cells residing and functioning in tissue, not blood, developing noninvasive methods for vivo quantification their biodistribution kinetics humans offers means studying key role adaptive immune response memory. This study is first report on using positron emission tomography (PET) dynamic imaging compartmental kinetic modeling measurement whole-body human subjects. For this, a 89Zr-labeled minibody with high affinity CD8 (89Zr-Df-Crefmirlimab) was used total-body...
Parallax error is a common issue in high-resolution preclinical positron emission tomography (PET) scanners as well clinical that have long axial field of view (FOV), which increases estimation uncertainty the annihilation position and therefore degrades spatial resolution. A way to address this depth-of-interaction (DOI) estimation. In work we propose two machine learning-based algorithms, dense convolutional neural network (NN), multiple linear regression (MLR)-based method estimate DOI...
Detectors for simultaneous positron emission tomography and magnetic resonance imaging in particular with sub-mm spatial resolution are commonly composed of scintillator crystal arrays, readout via arrays solid state sensors, such as avalanche photo diodes (APDs) or silicon photomultipliers (SiPMs). Usually a light guide between the crystals sensor is used to enable identification which smaller than elements. However, this complicates at gaps edges arrays. A solution use many sensors direct...
ABSTRACT Immunotherapies, especially the checkpoint inhibitors such as anti-PD-1 antibodies, have transformed cancer treatment by enhancing immune system’s capability to target and kill cells. However, predicting immunotherapy response remains challenging. 18 F-AraG is a molecular imaging tracer targeting activated T cells, which may facilitate therapy assessment non-invasive quantification of cell activity within tumor microenvironment elsewhere in body. The aim this study was obtain...
This paper evaluates the performance of a new type PET detectors called sensitivity encoded silicon photomultiplier (SeSP), which allows direct coupling small-pitch crystal arrays to detector with reduction in number readout channels. Four SeSP devices two separate encoding schemes 1D and 2D were investigated this study. Furthermore, both manufactured different sizes 4 ×4 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> 7. 73 ×7. 9 ,...
Conventional whole-body 18 F-FDG PET imaging provides a semi-quantitative evaluation of overall glucose metabolism without gaining insight into the specific transport and metabolic steps. Here we demonstrate ability total-body multiparametric to quantitatively evaluate using macroparametric quantification assess delivery phosphorylation processes microparametric for studying recovery from coronavirus disease 2019 (COVID-19).The study included thirteen healthy subjects twelve recovering...
Dual-energy computed tomography (DECT) enables material decomposition for tissues and produces additional information PET/CT imaging to potentially improve the characterization of diseases. PET-enabled DECT (PDECT) allows generation PET images simultaneously with a conventional scanner without need second x-ray CT scan. In PDECT, high-energy γ-ray (GCT) at 511 keV are obtained from time-of-flight (TOF) data combined existing form imaging. We have developed kernel-based maximum-likelihood...