Arterial spin labeling (ASL) MRI is a promising, noninvasive technique to image cerebral blood flow (CBF) but difficult use in cerebrovascular patients with abnormal, long arterial transit times through collateral pathways. To be clinically adopted, ASL must first optimized and validated against reference standard these challenging patient cases.We compared standard-delay (post-label delay=2.025 seconds), multidelay delay=0.7-3.0 long-label long-delay acquisitions delay=4.0 seconds)...

More widespread use of positron emission tomography (PET) imaging is limited by its high cost and radiation dose. Reductions in PET scan time or radiotracer dosage typically degrade diagnostic image quality (DIQ). Deep-learning-based reconstruction may improve DIQ, but such methods have not been clinically evaluated a realistic multicenter, multivendor environment. In this study, we the performance generalizability deep-learning-based image-quality enhancement algorithm applied to fourfold...

15 O-H 2 O PET imaging is an accurate method to measure cerebral blood flow (CBF) but it requires arterial input function (AIF). Historically, image-derived AIF estimation suffers from low temporal resolution, spill-in, and spill-over problems. Here, we optimized tracer dose on a time-of-flight PET/MR according the acquisition-specific noise-equivalent count rate curve. An of 850 MBq was determined, which allowed sufficient counts reconstruct short time-frame angiogram (PETA) during phase....

Abstract Tissue hypoxia occurs in pathologic conditions, such as cancer, ischemic heart disease and stroke when oxygen demand is greater than supply. An imaging method that can differentiate hypoxic versus normoxic tissue could have an immediate impact on therapy choices. In this work, the gadolinium(III) complex of 1,4,7,10‐tetraazacyclododecane‐1,4,7,10‐tetraacetic acid (DOTA) with a 2‐nitroimidazole attached to one carboxyl group via amide linkage was prepared, characterized tested...

Abstract Hexamethyldisiloxane (HMDSO) has been identified as a sensitive proton NMR indicator of tissue oxygenation (pO 2 ) based on spectroscopic spin‐lattice relaxometry. A rapid MRI approach now designed, implemented, and tested. The technique, imaging siloxanes to map levels (PISTOL), utilizes frequency‐selective excitation the HMDSO resonance chemical‐shift selective suppression residual water signal effectively eliminate fat signals pulse‐burst saturation recovery 1 H echo planar T...

The purpose of this study was to assess safety, biodistribution, and radiation dosimetry in humans for the highly selective σ-1 receptor PET agent ¹⁸F-6-(3-fluoropropyl)-3-(2-(azepan-1-yl)ethyl)benzo[<i>d</i>]thiazol-2(3H)-one (¹⁸F-FTC-146). <b>Methods:</b> Ten healthy volunteers (5 women, 5 men; age ± SD, 34.3 6.5 y) were recruited, written informed consent obtained from all participants. Series whole-body PET/MRI examinations acquired up 3 h after injection (357.2...

Florbetaben, a 18F-labeled stilbene derivative (Neuraceq®, formerly known as BAY-949172), is diagnostic radiopharmaceutical developed to visualize β-amyloid plaques in the brain. Here, we report pilot study evaluating patients with suspected cardiac amyloidosis for systemic extent of disease. We prospectively enrolled nine patients, 61–86 year old (mean ± SD 69.4 8.6), referred from amyloid clinic. First, dynamic imaging heart was acquired immediately after injection 222–318.2 MBq 270.1...

Gallium-68-labeled radiopharmaceuticals pose a challenge for scatter estimation because their targeted nature can produce high contrast in these regions of the kidneys and bladder. Even small errors estimate result washout artifacts. Administration diuretics reduce artifacts, but they may adverse events. Here, we investigated ability algorithmic modifications to mitigate artifacts eliminate need or other interventions.

To investigate if a deep learning convolutional neural network (CNN) could enable low-dose fluorine 18 (18F) fluorodeoxyglucose (FDG) PET/MRI for correct treatment response assessment of children and young adults with lymphoma.In this secondary analysis prospectively collected data (ClinicalTrials.gov identifier: NCT01542879), 20 patients lymphoma (mean age, 16.4 years ± 6.4 [standard deviation]) underwent 18F-FDG between July 2015 August 2019 at baseline after induction chemotherapy....

Quantitative in vivo oximetry has been reported using 19 F MRI conjunction with reporter molecules, such as perfluorocarbons, for tissue oxygenation ( p O 2 ). Recently, hexamethyldisiloxane (HMDSO) proposed a promising alternative molecule 1 H MRI‐based measurement of . To aid biocompatibility potential systemic administration, we prepared various nanoemulsion formulations wide range HMDSO volume fractions and to surfactant ratios. Calibration curves R versus ) all emulsion were found be...

Abstract There is increasing interest in the development of reporter agents to reveal enzyme activity vivo using imaging small animals. We have previously demonstrated feasibility detecting lacZ gene commercially available 3,4‐cyclohexenoesculetin‐β‐ D ‐galactopyranoside (S‐Gal) as a 1 H MRI reporter. Specifically, β‐galactosidase (β‐gal) releases aglycone, which forms magnetic resonance contrast‐inducing paramagnetic precipitate presence Fe 3+ . Contrast was primarily T 2 ‐weighted signal...

To investigate the efficacy of a novel respiratory motion scheme, where only center k-space is gated using navigators, versus fully respiratory-gated acquisition for three-dimensional flow imaging.Three-dimensional images were acquired axially gradient echo sequence in volume, covering ascending and descending aorta, pulmonary artery bifurcation 12 healthy subjects (33.2 ± 15.8 years; five men). For compensation, two gating tracking strategies used with 7-mm window: (1) All within window...

An emerging need for evaluation of promising cellular therapies is a non-invasive method to image the movement and health cells following transplantation.However, use single modality serve this purpose may not be advantageous as it convey inaccurate or insufficient information.Multi-modal imaging strategies are becoming more popular in vivo molecular because their improved sensitivity, higher resolution structural/functional visualization.This study aims at formulating Nile Red doped...

Purpose To develop a positron emission tomography (PET)/magnetic resonance (MR) imaging protocol for evaluation of the brain, heart, and joints pediatric cancer survivors chemotherapy-induced injuries in one session. Materials Methods Three teams experts neuroimaging, cardiac imaging, bone were tasked to 20-30-minute PET/MR detection tissue bone. In an institutional review board-approved, HIPAA-compliant, prospective study from April July 2016, 10 who completed chemotherapy underwent with...

Integrated PET/MRI is a hybrid imaging technique enabling clinicians to acquire diagnostic images for tumor assessment and treatment monitoring with both high soft tissue contrast added metabolic information. has shown be valuable in the clinical setting many promising future applications. The protocol presented here will provide step-by-step instructions acquisition of whole-body 2-deoxy-2-(18F)fluoro-D-glucose (18F-FDG) data children cancer. It also provides on how combine staging scan...

Abstract Tissue oximetry can assist in diagnosis and prognosis of many diseases enable personalized therapy. Previously, we reported the ability hexamethyldisiloxane (HMDSO) for accurate measurements tissue oxygen tension (pO 2 ) using Proton Imaging Siloxanes to map Oxygenation Levels (PISTOL) magnetic resonance imaging. Here report feasibility several commercially available linear cyclic siloxanes (molecular weight 162–410 g/mol) as PISTOL-based reporters by characterizing their...

Magnetic gold-coated iron oxide nanoparticles (Fe@Au NPs) have recently emerged as a new type of nanoparticle based magnetic resonance imaging (MRI) contrast agents, in which the gold shell provides conveniently tunable surface for presentation multiple functional molecules. Given versatility this nanoplatform and intrinsic sensitivity limitation MRI approach was developed work to incorporate radioisotopes with suitable half-lives into core Fe@Au NPs impart superior nuclear nanoplatform. The...

Integrated PET/MRI is a hybrid imaging technique enabling clinicians to acquire diagnostic images for tumor assessment and treatment monitoring with both high soft tissue contrast added metabolic information. has shown be valuable in the clinical setting many promising future applications. The protocol presented here will provide step-by-step instructions acquisition of whole-body 2-deoxy-2-(18F)fluoro-D-glucose (18F-FDG) data children cancer. It also provides on how combine staging scan...

An unrolled network with explicit MR image degradation modeling and physical property constraints, termed PGDNet, is proposed for adaptive denoising deblurring. Preliminary evaluation demonstrated that PGDNet can achieve similar/superior quality enhancement compared to the conventional task-specific networks, outperform others in joint deblurring tasks. provides a promising solution restore of accelerated clinical scans.