Publications by authors named "Mary McLean"

Introduction: Localised renal masses are an increasing burden on healthcare due to the rising number of cases. However, conventional imaging cannot reliably distinguish between benign and malignant renal masses, and renal mass biopsies are unable to characterise the entirety of the tumour due to sampling error, which may lead to delayed treatment or overtreatment. There is an unmet clinical need to develop novel imaging techniques to characterise renal masses more accurately.

View Article and Find Full Text PDF
Article Synopsis
  • Hyperpolarized carbon-13 (C) MRI can non-invasively evaluate how the brain metabolizes [1-C]pyruvate, revealing insights about enzymatic activities beyond the commonly studied lactate dehydrogenase (LDH) and pyruvate dehydrogenase (PDH).
  • After injecting hyperpolarized pyruvate, researchers detected cerebral carbon dioxide (CO) and bicarbonate (HCO3), allowing for brain pH measurements, which averaged 7.40 in a small sample of volunteers, indicating the method's reliability.
  • The study also identified hyperpolarized [1-C]aspartate and alanine, suggesting additional metabolic pathways and localization of alanine to skeletal muscle, emphasizing
View Article and Find Full Text PDF

Hyperpolarised magnetic resonance imaging (HP-C-MRI) has shown promise as a clinical tool for detecting and characterising prostate cancer. Here we use a range of spatially resolved histological techniques to identify the biological mechanisms underpinning differential [1-C]lactate labelling between benign and malignant prostate, as well as in tumours containing cribriform and non-cribriform Gleason pattern 4 disease. Here we show that elevated hyperpolarised [1-C]lactate signal in prostate cancer compared to the benign prostate is primarily driven by increased tumour epithelial cell density and vascularity, rather than differences in epithelial lactate concentration between tumour and normal.

View Article and Find Full Text PDF

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.

View Article and Find Full Text PDF

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.

View Article and Find Full Text PDF

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.

View Article and Find Full Text PDF
Article Synopsis
  • - MRI with hyperpolarized (HP) C agents allows for the measurement of altered metabolism in various diseases, including cancers and organ diseases, and has seen increased application in human studies over the last decade due to improved preparation methods of HP agents.
  • - This paper focuses on the use of [1-C]pyruvate, the most popular HP agent, and is organized into four main sections: agent preparation, MRI system setup, data collection, and analysis, highlighting essential components for effective studies.
  • - The findings come from the "HP C MRI Consensus Group" and aim to provide a comprehensive guide for best practices, addressing both successful studies and existing gaps, while fostering future advancements in metabolic imaging.
View Article and Find Full Text PDF
Article Synopsis
  • * Patients with intermediate-risk prostate cancer could benefit from more advanced diagnostic techniques to better assess their risk.
  • * The study demonstrates that imaging tumor lactate using hyperpolarized C MRI can help identify patients likely to experience BCR, supporting further research on this metabolic imaging approach in clinical settings.
View Article and Find Full Text PDF

MRI with hyperpolarized (HP) C agents, also known as HP C MRI, can measure processes such as localized metabolism that is altered in numerous cancers, liver, heart, kidney diseases, and more. It has been translated into human studies during the past 10 years, with recent rapid growth in studies largely based on increasing availability of hyperpolarized agent preparation methods suitable for use in humans. This paper aims to capture the current successful practices for HP MRI human studies with [1-C]pyruvate - by far the most commonly used agent, which sits at a key metabolic junction in glycolysis.

View Article and Find Full Text PDF

Kratom () is an herb that is sold over the counter in both pill and liquid forms. It contains opioid and stimulant properties and is used for relaxation as well as for weaning off opioid addictions. While a few adverse effects of kratom have been already reported, mainly with concerns around its toxicity, very little is known about it.

View Article and Find Full Text PDF

Introduction: Hospitals have implemented various wellness interventions to offset the negative effects of coronavirus disease 2019 (COVID-19) on emergency physician morale and burnout. There is limited high quality evidence regarding effectiveness of hospital-directed wellness interventions, leaving hospitals without guidance on best practices. We sought to determine intervention effectiveness and frequency of use in the spring/summer 2020.

View Article and Find Full Text PDF

Background: Hospitals have implemented innovative strategies to address overcrowding by optimizing patient flow through the emergency department (ED). Vertical split flow refers to the concept of assigning patients to vertical chairs instead of horizontal beds based on patient acuity.

Objective: Evaluate the impact of vertical split flow implementation on ED Emergency Severity Index (ESI) level 3, patient length of stay, and throughput at a community hospital.

View Article and Find Full Text PDF

There is increasing evidence to support the use of temozolomide therapy for the treatment of metastatic phaeochromocytoma/paraganglioma (PPGL) in adults, particularly in patients with mutations. In children however, very little data is available. In this report, we present the case of a 12-year-old female with a SDHB-related metastatic paraganglioma treated with surgery followed by temozolomide therapy.

View Article and Find Full Text PDF

Objectives: To investigate the relationship between magnetization transfer (MT) imaging and tissue macromolecules in high-grade serous ovarian cancer (HGSOC) and whether MT ratio (MTR) changes following neoadjuvant chemotherapy (NACT).

Methods: This was a prospective observational study. 12 HGSOC patients were imaged before treatment.

View Article and Find Full Text PDF
Article Synopsis
  • This study aimed to assess glioblastoma metabolism using hyperpolarized carbon-13 MRI by tracking the exchange of hyperpolarized carbon from injected [1-C]pyruvate to tumor lactate and bicarbonate.
  • Seven treatment-naive GBM patients underwent imaging, revealing that the bicarbonate-to-pyruvate ratio was significantly lower in tumors compared to normal brain areas, while lactate levels were similar.
  • The research indicated strong correlations between the intensities of lactate and bicarbonate signals and pyruvate, suggesting variations in tumor metabolism that could have implications for understanding glioblastoma.
View Article and Find Full Text PDF

Hyperpolarised [1-C]pyruvate MRI (HP-C-MRI) is an emerging metabolic imaging technique that has shown promise for evaluating prostate cancer (PCa) aggressiveness. Accurate tumour delineation on HP-C-MRI is vital for quantitative assessment of the underlying tissue metabolism. However, there is no consensus on the optimum method for segmenting HP-C-MRI, and whole-mount pathology (WMP) as the histopathological gold-standard is only available for surgical patients.

View Article and Find Full Text PDF

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.

View Article and Find Full Text PDF

Background: Following mild traumatic brain injury (mTBI), also known as concussion, many patients with chronic symptoms (>3 months post injury) receive conventional imaging such as computed tomography (CT) or magnetic resonance imaging (MRI). However, these modalities often do not show changes after mTBI. We studied the benefit of triaging patients with ongoing symptoms >3 months post injury by quantitative electroencephalography (qEEG) and then completing a brain single positron emission computed tomography (SPECT) to aid in diagnosis and early detection of brain changes.

View Article and Find Full Text PDF
Article Synopsis
  • Breast cancer is a major health issue, and researchers are exploring the use of non-invasive sodium MRI to improve diagnosis and treatment monitoring in preclinical models.* -
  • In studies with mice that had breast tumors, sodium MRI showed higher sodium levels in tumor areas compared to normal tissues, linking these levels to increased cell density.* -
  • The combination of sodium MRI and diffusion-weighted imaging provided better classification of tumor regions, suggesting that sodium MRI could serve as a more sensitive and non-invasive biomarker for tracking treatment response.*
View Article and Find Full Text PDF

In the community, there is a need to more objectively evaluate the response of common chronic psychiatric disorders to treatment. Brain single photon emission computed tomography (SPECT) indirectly measures cerebral functional activity by uptake of a radiotracer, which follows regional cerebral blood flow. Brain 3D Thresholded SPECT scans are thresholded three dimensional images derived from brain SPECT data.

View Article and Find Full Text PDF

Introduction: The 2019 novel coronavirus pandemic has caused significant disruptions in the clinical operations of hospitals as well as clinical education, training, and research at academic centers. New York State was among the first and largest epicenters of the pandemic, resulting in significant disruptions across its 29 emergency medicine (EM) residency programs. We conducted a cross-sectional observational study of EM residency programs in New York State to assess the impact of the pandemic on resident education and training programs.

View Article and Find Full Text PDF
Article Synopsis
  • HP C-MRI is a new imaging technique that helps differentiate aggressive prostate cancer from less serious types by analyzing lactate production after injecting hyperpolarised [1-C]pyruvate.
  • The study found that HP C-MRI primarily measures metabolic activity in the cancer's epithelial cells rather than the surrounding stroma, correlating MRI results with the expression of key metabolic enzymes and transporters.
  • This method was also validated through comparisons with existing data on tumours, showing consistent metabolic patterns that can help in identifying clinically significant disease based on cellular differences.
View Article and Find Full Text PDF

Background: The COVID-19 pandemic displaced newly matched emergency medicine "pre-interns" from in-person educational experiences at the end of medical school. This called for novel remote teaching modalities.

Objective: This study assesses effectiveness of a multisite Accreditation Council for Graduate Medical Education (ACGME) sub-competency-based curricular implementation on Slack during the first wave of the COVID-19 pandemic in the United States.

View Article and Find Full Text PDF