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.

A Randomized, Double-Blind, Placebo-Controlled, Short-Term Monotherapy Study of MK-6186, an HIV-1 Non-Nucleoside Reverse Transcriptase Inhibitor, in Treatment-Naïve HIV-Infected Participants.

To assess the antiviral activity, pharmacokinetics, and safety of MK-6186 in HIV-1 non-nucleoside reverse transcriptase inhibitor (NNRTI)-naïve, HIV-1-infected male participants. Double-blind, randomized, two-panel study. In 2 sequential panels, 18 participants received MK-6186 (40 mg [Panel A] or 150 mg [Panel B]) or matching placebo once daily for 7 days.

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.

Assessment of lesion insertion tool in pelvis PET/MR data with applications to attenuation correction method development.

Background: In modern positron emission tomography (PET) with multi-modality imaging (e.g., PET/CT and PET/MR), the attenuation correction (AC) is the single largest correction factor for image reconstruction.

Pollen effects in a changing climate: Ragweed pollen exposure and sleepiness in immunotherapy patients of a Southeastern Michigan allergy clinic.

Allergic rhino-conjunctivitis (AR) is a globally relevant health disorder characterized by sneezing, rhinorrhea and sleep disturbance. Ragweed (Ambrosia artemisiifolia) is a plant common to North America and an important allergen. Coarse methods of measuring airborne pollen counts are used to predict seasonal allergy symptoms.

Therapeutic DBS for OCD Suppresses the Default Mode Network.

Background: Deep brain stimulation (DBS) of the anterior limb of the internal capsule (ALIC) is an emerging 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.

Preclinical evaluation of transaxial intraputaminal trajectory for enhanced distribution of grafted cells in Parkinson's disease.

Objective: The objective of this study was to develop and evaluate the feasibility and safety of a novel transaxial surgical approach for the delivery of human induced pluripotent stem cell-derived dopaminergic neuroprogenitor cells (DANPCs) into the putamen nucleus using nonhuman primates and surgical techniques and tools relevant to human clinical translation.

Methods: Nine immunosuppressed, unlesioned adult cynomolgus macaques (4 females, 5 males) received intraputaminal injections of vehicle or DANPCs (0.9 × 105 to 1.

Precision targeting in the globus pallidus interna: insights from the multicenter, prospective, blinded VA/NINDS CSP 468 study.

Objective: Deep brain stimulation (DBS) targeting the globus pallidus interna (GPi) has been shown to significantly improve motor symptoms for the treatment of medication-refractory Parkinson's disease. Yet, heterogeneity in clinical outcomes persists, possibly due to suboptimal target identification within the GPi. By leveraging robust sampling of the GPi and 6-month postsurgical outcomes, this study aims to determine optimal symptom-specific GPi DBS targets.

Protocol for producing hyperpolarized C-bicarbonate for clinical MRI of extracellular pH in aggressive tumors.

Tumor acidosis is one of the hallmarks indicating the initiation and progression of various cancers. Here, we present a protocol for preparing a hyperpolarized (HP) C-bicarbonate tissue pH MRI imaging contrast agent to detect aggressive tumors. We describe the steps for the formulation and polarization of a precursor molecule C-glycerol carbonate (C-GLC), the post-dissolution reaction, and converting HP C-GLC to an injectable HP C-bicarbonate solution.

Linac- and CyberKnife-based MRI-only treatment planning of prostate SBRT using an optimized synthetic CT calibration curve.

Purpose: CT Hounsfield Units (HUs) are converted to electron density using a calibration curve obtained from physical measurements of an electron density phantom. HU values assigned to an MRI-derived synthetic computed tomography (sCT) may present a different relationship with electron density compared to CT HU. Correct assignment of sCT HU values is critical for accurate dose calculation and delivery.

A pharmacokinetic model for hyperpolarized C-pyruvate MRI when using metabolite-specific bSSFP sequences.

Purpose: Metabolite-specific balanced SSFP (MS-bSSFP) sequences are increasingly used in hyperpolarized [1-C]Pyruvate (HP C) MRI studies as they improve SNR by refocusing the magnetization each TR. Currently, pharmacokinetic models used to fit conversion rate constants, k and k, and rate constant maps do not account for differences in the signal evolution of MS-bSSFP acquisitions.

Methods: In this work, a flexible MS-bSSFP model was built that can be used to fit conversion rate constants for these experiments.

Data Format Standardization and DICOM Integration for Hyperpolarized C MRI.

Hyperpolarized (HP) C MRI has shown promise as a valuable modality for measurements of metabolism and is currently in human trials at 15 research sites worldwide. With this growth it is important to adopt standardized data storage practices as it will allow sites to meaningfully compare data. In this paper we (1) describe data that we believe should be stored and (2) demonstrate pipelines and methods that utilize the Digital Imaging and Communications in Medicine (DICOM) standard.

Data Format Standardization and DICOM Integration for Hyperpolarized C MRI.

Hyperpolarized (HP) C MRI has shown promise as a valuable modality for in vivo measurements of metabolism and is currently in human trials at 15 research sites worldwide. With this growth, it is important to adopt standardized data storage practices as it will allow sites to meaningfully compare data. In this paper, we (1) describe data that we believe should be stored and (2) demonstrate pipelines and methods that utilize the Digital Imaging and Communications in Medicine (DICOM) standard.

Psychotropic Medication Use and Polypharmacy Among Children and Adolescents Initiating Intensive Behavioral Therapy for Severe Challenging Behavior.

Objective: To evaluate the prevalence, trends, and factors associated with psychotropic medication use and polypharmacy among children and adolescents initiating intensive behavioral therapy for severe challenging behavior over a 10-year period.

Study Design: In this retrospective observational study, we examined data from caregiver interviews and patient medical records on the number and types of psychotropic medications prescribed to patients initiating intensive behavioral therapy between January 1, 2013, and December 31, 2022. Trends in medication use and polypharmacy across the 10-year period were analyzed using regression analysis, while differences in demographics and clinical factors for patients with use and polypharmacy were analyzed using nonparametric statistical analysis with odds ratios presented for significant factors.

Drug delivery systems for wound healing treatment of upper airway injury.

Introduction: Endotracheal intubation is a common procedure to maintain an open airway with risks for traumatic injury. Pathological changes resulting from intubation can cause upper airway complications, including vocal fold scarring, laryngotracheal stenosis, and granulomas and present with symptoms such as dysphonia, dysphagia, and dyspnea. Current intubation-related laryngotracheal injury treatment approaches lack standardized guidelines, relying on individual clinician experience, and surgical and medical interventions have limitations and carry risks.

Mixed Supervision of Histopathology Improves Prostate Cancer Classification From MRI.

Non-invasive prostate cancer classification from MRI has the potential to revolutionize patient care by providing early detection of clinically significant disease, but has thus far shown limited positive predictive value. To address this, we present a image-based deep learning method to predict clinically significant prostate cancer from screening MRI in patients that subsequently underwent biopsy with results ranging from benign pathology to the highest grade tumors. Specifically, we demonstrate that mixed supervision via diverse histopathological ground truth improves classification performance despite the cost of reduced concordance with image-based segmentation.

Preliminary analyses of accumulation of carcinogenic contaminants on retired firefighter ensembles.

Personal protective equipment (PPE) is designed to protect firefighters from hazards encountered on the fire scene, including heat and products of combustion. Decontamination practices for firefighter turnout gear have been developed to remove combustion products and other contaminants from the fabric of structural firefighting ensembles (i.e.

Tractography-based DBS lead repositioning improves outcome in refractory OCD and depression.

Deep brain stimulation (DBS) of the anterior limb of the internal capsule (ALIC) has been used to treat refractory obsessive-compulsive disorder (OCD) and depression, but outcomes are variable, with some patients not responding to this form of invasive neuromodulation. A lack of benefit in some patients may be due to suboptimal positioning of DBS leads. Recently, studies have suggested that specific white matter tracts within the ALIC are associated with improved outcomes.

Scan-Specific Self-Supervised Bayesian Deep Non-Linear Inversion for Undersampled MRI Reconstruction.

Magnetic resonance imaging is subject to slow acquisition times due to the inherent limitations in data sampling. Recently, supervised deep learning has emerged as a promising technique for reconstructing sub-sampled MRI. However, supervised deep learning requires a large dataset of fully-sampled data.