Publications by authors named "Mark Widmaier"
The creatine kinase (CK) is a key enzyme involved in brain bioenergetics, playing a key role in brain function and the pathogenesis of neurological and psychiatric diseases, but imaging its activity noninvasively in the human brain in vivo remains a significant challenge. This study aims to advance the magnetization transfer (MT)- P magnetic resonance fingerprinting (MRF) for 3D Creatine Kinase Imaging (CKI). The method was implemented and validated on a clinical 7 Tesla MRI scanner.
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- Phosphorus Magnetic Resonance Spectroscopy (P MRS) is a noninvasive technique used to assess energy metabolism, but high magnetic fields often create sensitivity and spatial issues; the novel fast double-angle method (fDAM) is proposed to address these challenges.
- The fDAM method utilizes advanced 3D acquisitions and frequency-selective pulses to efficiently map phosphocreatine signals at 7T, showing promising results in both phantom studies and human brain/muscle applications.
- The study findings demonstrate that fDAM provides a strong correlation with traditional methods while significantly reducing mapping time and improving coverage, suggesting its potential for quick P MRSI applications in future research.
Purpose: Phosphorus Magnetic Resonance Spectroscopy (P MRS) enables non-invasive assessment of energy metabolism, yet its application is hindered by sensitivity limitations. To overcome this, often high magnetic fields are used, leading to challenges such as spatial inhomogeneity and therefore the need for accurate flip angle determination in accelerated acquisitions with short repetition times . In response to these challenges, we propose a novel short and look-up table-based Double-Angle Method for fast 3D P mapping (fDAM).
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- NAD is crucial for the brain's circadian clock but its metabolism in humans is not well understood.
- A study using magnetic resonance spectroscopy examined NAD levels in the occipital brain at different times of day with 25 participants, confirming physiological differences through salivary cortisol.
- Results showed that circadian rhythm had no significant impact on NAD or other metabolites, except for taurine, while it did affect risk-taking behavior and cortisol levels.
A new and efficient magnetisation transfer P magnetic resonance fingerprinting (MT- P-MRF) approach is introduced to measure the creatine kinase metabolic rate between phosphocreatine (PCr) and adenosine triphosphate (ATP) in human brain. The MRF framework is extended to overcome challenges in conventional P measurement methods in the human brain, enabling reduced acquisition time and specific absorption rate (SAR). To address the challenge of creating and matching large multiparametric dictionaries in an MRF scheme, a nested iteration interpolation method (NIIM) is introduced.
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