Spatially constrained hyperpolarized 13C MRI pharmacokinetic rate constant map estimation using a digital brain phantom and a U-Net.

Fitting rate constants to Hyperpolarized [1-C]Pyruvate (HP C13) MRI data is a promising approach for quantifying metabolism in vivo. Current methods typically fit each voxel of the dataset using a least-squares objective. With these methods, each voxel is considered independently, and the spatial relationships are not considered during fitting.

Chronic and infectious respiratory mortality and short-term exposures to four types of pollen taxa in older adults in Michigan, 2006-2017.

Introduction: Levels of plant-based aeroallergens are rising as growing seasons lengthen and intensify with anthropogenic climate change. Increased exposure to pollens could increase risk for mortality from respiratory causes, particularly among older adults. We determined short-term, lag associations of four species classes of pollen (ragweed, deciduous trees, grass pollen and evergreen trees) with respiratory mortality (all cause, chronic and infectious related) in Michigan, USA.

Therapeutic DBS for OCD Suppresses the Default Mode Network.

Deep brain stimulation (DBS) of the anterior limb of the internal capsule (ALIC) is a circuit-based treatment for severe, refractory obsessive-compulsive disorder (OCD). The therapeutic effects of DBS are hypothesized to be mediated by direct modulation of a distributed cortico-striato-thalmo-cortical network underlying OCD symptoms. However, the exact underlying mechanism by which DBS exerts its therapeutic effects still remains unclear.

Time-resolved MR fingerprinting for T* signal extraction: MR fingerprinting meets echo planar time-resolved imaging.

Purpose: This study leverages the echo planar time-resolved imaging (EPTI) concept in MR fingerprinting (MRF) framework for a new time-resolved MRF (TRMRF) approach, and explores its capability for fast simultaneous quantification of multiple MR parameters including T, T, T*, proton density, off resonance, and B .

Methods: The proposed TRMRF method uses the concept of EPTI to track the signal change along the EPI echo train for T* weighting with a k-t Poisson-based sampling order designed for acquisition. A two-dimensional decomposition algorithm was designed for the image reconstruction, enabling fast and precise subspace modeling.

Initial Experience of Metabolic Imaging with Hyperpolarized [1-C]pyruvate MRI in Kidney Transplant Patients.

Background: Kidney transplant is the treatment of choice for patients with end-stage renal disease. Early detection of allograft injury is important to delay or prevent irreversible damage.

Purpose: To investigate the feasibility of hyperpolarized (HP) [1-C]pyruvate MRI for assessing kidney allograft metabolism.