Local arterial administration of acidified malonate as an adjunct therapy to mechanical thrombectomy in ischemic stroke.

Aims: Ischemic stroke is increasingly treated by mechanical thrombectomy (MT) with the more rapid and complete reperfusion of the ischemic tissue, enhancing patient outcome, compared to recombinant tissue plasminogen activator (rtPA) alone. Even so, there is still extensive brain infarction and disability following MT, which is exacerbated by ischemia-reperfusion injury (IRI) and other pathological processes during reperfusion. Hence, an adjunct therapy to MT that decreases IRI should enhance patient outcomes.

Development and optimization of human deuterium MR spectroscopic imaging at 3 T in the abdomen.

Purpose: To establish and optimize abdominal deuterium MR spectroscopic imaging in conjunction with orally administered H-labeled molecules.

Methods: A flexible transmit-receive surface coil was used to image naturally abundant deuterium signal in phantoms and healthy volunteers and after orally administered HO in a patient with a benign renal tumor (oncocytoma).

Results: Water and lipid peaks were fitted with high confidence from both unlocalized spectra and from voxels within the liver, kidney, and spleen on spectroscopic imaging.

K-Means Clustering of Hyperpolarised C-MRI Identifies Intratumoral Perfusion/Metabolism Mismatch in Renal Cell Carcinoma as the Best Predictor of the Highest Grade.

: Early and accurate grading of renal cell carcinoma (RCC) improves patient risk stratification and has implications for clinical management and mortality. However, current diagnostic approaches using imaging and renal mass biopsy have limited specificity and may lead to undergrading. : This study explored the use of hyperpolarised [1-C]pyruvate MRI (HP C-MRI) to identify the most aggressive areas within the tumour of patients with clear cell renal cell carcinoma (ccRCC) as a method to guide biopsy targeting and to reduce undergrading.

Multiparametric MRI-Based Deep Learning Radiomics Model for Assessing 5-Year Recurrence Risk in Non-Muscle Invasive Bladder Cancer.

Background: Accurately assessing 5-year recurrence rates is crucial for managing non-muscle-invasive bladder carcinoma (NMIBC). However, the European Organization for Research and Treatment of Cancer (EORTC) model exhibits poor performance.

Purpose: To investigate whether integrating multiparametric MRI (mp-MRI) with clinical factors improves NMIBC 5-year recurrence risk assessment.

Deuterium Metabolic Imaging of Alzheimer Disease at 3-T Magnetic Field Strength: A Pilot Case-Control Study.

Background Impaired glucose metabolism is characteristic of several types of dementia, preceding cognitive symptoms and structural brain changes. Reduced glucose uptake in specific brain regions, detected using fluorine 18 (F) fluorodeoxyglucose (FDG) PET, is a valuable diagnostic marker in Alzheimer disease (AD). However, the use of F-FDG PET in clinical practice may be limited by equipment availability and high cost.

Na MRI: inter-reader reproducibility of normal fibroglandular sodium concentration measurements at 3 T.

Background: To study the reproducibility of Na magnetic resonance imaging (MRI) measurements from breast tissue in healthy volunteers.

Methods: Using a dual-tuned bilateral Na/H breast coil at 3-T MRI, high-resolution Na MRI three-dimensional cones sequences were used to quantify total sodium concentration (TSC) and fluid-attenuated sodium concentration (FASC). B-corrected TSC and FASC maps were created.

Deep learning-based quantification of osteonecrosis using magnetic resonance images in Gaucher disease.

Gaucher disease is one of the most common lysosomal storage disorders. Osteonecrosis is a principal clinical manifestation of Gaucher disease and often leads to joint collapse and fractures. T1-weighted (T1w) modality in MRI is widely used to monitor bone involvement in Gaucher disease and to diagnose osteonecrosis.

Quantitative Na magnetic resonance imaging in the abdomen at 3 T.

Objectives: To assess the feasibility of sodium-23 MRI for performing quantitative and non-invasive measurements of total sodium concentration (TSC) and relaxation in a variety of abdominal organs.

Materials And Methods: Proton and sodium imaging of the abdomen was performed in 19 healthy volunteers using a 3D cones sequence and a sodium-tuned 4-rung transmit/receive body coil on a clinical 3 T system. The effects of B non-uniformity on TSC measurements were corrected using the double-angle method.

New Horizons in Hyperpolarized C MRI.

Hyperpolarization techniques significantly enhance the sensitivity of magnetic resonance (MR) and thus present fascinating new directions for research and applications with in vivo MR imaging and spectroscopy (MRI/S). Hyperpolarized C MRI/S, in particular, enables real-time non-invasive assessment of metabolic processes and holds great promise for a diverse range of clinical applications spanning fields like oncology, neurology, and cardiology, with a potential for improving early diagnosis of disease, patient stratification, and therapy response assessment. Despite its potential, technical challenges remain for achieving clinical translation.

Deuterium metabolic imaging and hyperpolarized C-MRI of the normal human brain at clinical field strength reveals differential cerebral metabolism.

Deuterium metabolic imaging (DMI) and hyperpolarized C-pyruvate MRI (C-HPMRI) are two emerging methods for non-invasive and non-ionizing imaging of tissue metabolism. Imaging cerebral metabolism has potential applications in cancer, neurodegeneration, multiple sclerosis, traumatic brain injury, stroke, and inborn errors of metabolism. Here we directly compare these two non-invasive methods at 3 T for the first time in humans and show how they simultaneously probe both oxidative and non-oxidative metabolism.

Hyperpolarized C-Pyruvate Metabolism as a Surrogate for Tumor Grade and Poor Outcome in Renal Cell Carcinoma-A Proof of Principle Study.

Differentiating aggressive clear cell renal cell carcinoma (ccRCC) from indolent lesions is challenging using conventional imaging. This work prospectively compared the metabolic imaging phenotype of renal tumors using carbon-13 MRI following injection of hyperpolarized [1-C]pyruvate (HP-C-MRI) and validated these findings with histopathology. Nine patients with treatment-naïve renal tumors (6 ccRCCs, 1 liposarcoma, 1 pheochromocytoma, 1 oncocytoma) underwent pre-operative HP-C-MRI and conventional proton (H) MRI.

Quantitative analysis of the ACL and PCL using T1rho and T2 relaxation time mapping: an exploratory, cross-sectional comparison between OA and healthy control knees.

Background: Quantitative magnetic resonance imaging (MRI) methods such as T1rho and T2 mapping are sensitive to changes in tissue composition, however their use in cruciate ligament assessment has been limited to studies of asymptomatic populations or patients with posterior cruciate ligament tears only. The aim of this preliminary study was to compare T1rho and T2 relaxation times of the anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) between subjects with mild-to-moderate knee osteoarthritis (OA) and healthy controls.

Methods: A single knee of 15 patients with mild-to-moderate knee OA (Kellgren-Lawrence grades 2-3) and of 6 age-matched controls was imaged using a 3.

Multiparametric MRI of early tumor response to immune checkpoint blockade in metastatic melanoma.

Background: Immune checkpoint inhibitors are now standard of care treatment for many cancers. Treatment failure in metastatic melanoma is often due to tumor heterogeneity, which is not easily captured by conventional CT or tumor biopsy. The aim of this prospective study was to investigate early microstructural and functional changes within melanoma metastases following immune checkpoint blockade using multiparametric MRI.

Federated learning for predicting clinical outcomes in patients with COVID-19.

Federated learning (FL) is a method used for training artificial intelligence models with data from multiple sources while maintaining data anonymity, thus removing many barriers to data sharing. Here we used data from 20 institutes across the globe to train a FL model, called EXAM (electronic medical record (EMR) chest X-ray AI model), that predicts the future oxygen requirements of symptomatic patients with COVID-19 using inputs of vital signs, laboratory data and chest X-rays. EXAM achieved an average area under the curve (AUC) >0.

Combined Na and C imaging at 3.0 Tesla using a single-tuned large FOV birdcage coil.

Purpose: An unmet need in carbon-13 ( C)-MRI is a transmit system that provides uniform excitation across a large FOV and can accommodate patients of wide-ranging body habitus. Due to the small difference between the resonant frequencies, sodium-23 ( Na) coil developments can inform C coil design while being simpler to assess due to the higher naturally abundant Na signal. Here we present a removable Na birdcage, which also allows operation as a C abdominal coil.

How to Design AI-Driven Clinical Trials in Nuclear Medicine.

Artificial intelligence (AI) is an overarching term for a multitude of technologies which are currently being discussed and introduced in several areas of medicine and in medical imaging specifically. There is, however, limited literature and information about how AI techniques can be integrated into the design of clinical imaging trials. This article will present several aspects of AI being used in trials today and how imaging departments and especially nuclear medicine departments can prepare themselves to be at the forefront of AI-driven clinical trials.

Characterization and correction of center-frequency effects in X-nuclear eddy current compensations on a clinical MR system.

Purpose: The aim of the study was to investigate whether incorrectly compensated eddy currents are the source of persistent X-nuclear spectroscopy and imaging artifacts, as well as methods to correct this.

Methods: Pulse-acquire spectra were collected for H and X-nuclei ( Na or P) using the minimum TR permitted on a 3T clinical MRI system. Data were collected in 3 orientations (axial, sagittal, and coronal) with the spoiler gradient at the end of the TR applied along the slice direction for each.