An essentially radiation-transparent body coil integrated with a patient rotation system for MR-guided particle therapy.

Background: The pursuit of adaptive radiotherapy using MR imaging for better precision in patient positioning puts stringent demands on the hardware components of the MR scanner. Particularly in particle therapy, the dose distribution and thus the efficacy of the treatment is susceptible to beam attenuation from interfering materials in the irradiation path. This severely limits the usefulness of conventional imaging coils, which contain highly attenuating parts such as capacitors and preamplifiers in an unknown position, and requires development of a dedicated radiofrequency (RF) coil with close consideration of the materials and components used.

Recent technical developments and clinical research applications of sodium (Na) MRI.

Sodium is an essential ion that plays a central role in many physiological processes including the transmembrane electrochemical gradient and the maintenance of the body's homeostasis. Due to the crucial role of sodium in the human body, the sodium nucleus is a promising candidate for non-invasively assessing (patho-)physiological changes. Almost 10 years ago, Madelin et al.

First implementation of dynamic oxygen-17 (O) magnetic resonance imaging at 7 Tesla during neuronal stimulation in the human brain.

Objective: First implementation of dynamic oxygen-17 (O) MRI at 7 Tesla (T) during neuronal stimulation in the human brain.

Methods: Five healthy volunteers underwent a three-phase O gas (O) inhalation experiment. Combined right-side visual stimulus and right-hand finger tapping were used to achieve neuronal stimulation in the left cerebral hemisphere.

First application of dynamic oxygen-17 magnetic resonance imaging at 7 Tesla in a patient with early subacute stroke.

Dynamic oxygen-17 (O) magnetic resonance imaging (MRI) is an imaging method that enables a direct and non-invasive assessment of cerebral oxygen metabolism and thus potentially the distinction between viable and non-viable tissue employing a three-phase inhalation experiment. The purpose of this investigation was the first application of dynamic O MRI at 7 Tesla (T) in a patient with stroke. In this proof-of-concept experiment, dynamic O MRI was applied during O inhalation in a patient with early subacute stroke.

Assessment of Sodium MRI at 7 Tesla as Predictor of Therapy Response and Survival in Glioblastoma Patients.

The purpose of this work was to prospectively investigate sodium (Na) MRI at 7 Tesla (T) as predictor of therapy response and survival in patients with glioblastoma (GBM). Thus, 20 GBM patients underwent Na MRI at 7T before, immediately after and 6 weeks after chemoradiotherapy (CRT). The median tissue sodium concentration (TSC) inside the whole tumor excluding necrosis was determined.

7 Tesla and Beyond: Advanced Methods and Clinical Applications in Magnetic Resonance Imaging.

Ultrahigh magnetic fields offer significantly higher signal-to-noise ratio, and several magnetic resonance applications additionally benefit from a higher contrast-to-noise ratio, with static magnetic field strengths of B0 ≥ 7 T currently being referred to as ultrahigh fields (UHFs). The advantages of UHF can be used to resolve structures more precisely or to visualize physiological/pathophysiological effects that would be difficult or even impossible to detect at lower field strengths. However, with these advantages also come challenges, such as inhomogeneities applying standard radiofrequency excitation techniques, higher energy deposition in the human body, and enhanced B0 field inhomogeneities.

3D sodium ( Na) magnetic resonance fingerprinting for time-efficient relaxometric mapping.

Purpose: To develop a framework for 3D sodium ( Na) MR fingerprinting (MRF), based on irreducible spherical tensor operators with tailored flip angle (FA) pattern and time-efficient data acquisition for simultaneous quantification of T , , , and in addition to ΔB .

Methods: Na-MRF was implemented in a 3D sequence and irreducible spherical tensor operators were exploited in the simulations. Furthermore, the Cramér Rao lower bound was used to optimize the flip angle pattern.

[Perspectives of X-nuclei magnetic resonance imaging in neuro-oncology].

Background: X‑nuclei magnetic resonance imaging (MRI) yields a broad spectrum of metabolic and functional imaging techniques with increasing clinical feasibility.

Objective: Current X‑nuclei techniques in (neuro)oncology with emphasis on potential clinical applications of sodium and oxygen MRI are described and discussed.

Materials And Methods: Review with discussion of state-of-the-art literature on X‑nuclei imaging.

Ultra-high-field sodium MRI as biomarker for tumor extent, grade and IDH mutation status in glioma patients.

Purpose: This prospective clinical trial investigated sodium (Na) MRI at 7 Tesla (T) field strength as biomarker for tumor extent, isocitrate dehydrogenase (IDH) mutation and O6-methylguanine DNA methyltransferase (MGMT) promotor methylation in glioma patients.

Methods: 28 glioma patients underwent Na MRI on a 7T scanner (Siemens Healthcare, Erlangen, Germany) parallel to standard 3T MRI before chemoradiation. Areas of Gadolinium-contrast enhancement (gdce), non-enhancing T2-hyperintensity (regarded as edema), necrosis, and normal-appearing white matter (nawm) were segmented on 3T MRI imaging and were co-registered with the Na images.

Quantitative Dynamic Oxygen 17 MRI at 7.0 T for the Cerebral Oxygen Metabolism in Glioma.

Background Altered metabolism is a characteristic of cancer. Because of a shift in glucose metabolism from oxidative phosphorylation to lactate production for energy generation, malignant tumors are characterized by increased glycolysis followed by lactic acid fermentation, even in the presence of abundant oxygen (the Warburg effect). Purpose To quantitatively investigate dynamic oxygen 17 (O) MRI in healthy participants and participants with untreated glioma to understand altered cerebral oxygen metabolism in glioma.

Multinuclear MRI at Ultrahigh Fields.

In this article, an overview of the current developments and research applications for non-proton magnetic resonance imaging (MRI) at ultrahigh magnetic fields (UHFs) is given. Due to technical and methodical advances, efficient MRI of physiologically relevant nuclei, such as Na, Cl, Cl, K, O, or P has become feasible and is of interest to obtain spatially and temporally resolved information that can be used for biomedical and diagnostic applications. Sodium (Na) MRI is the most widespread multinuclear imaging method with applications ranging over all regions of the human body.

Corrections of myocardial tissue sodium concentration measurements in human cardiac Na MRI at 7 Tesla.

Purpose: To quantify the tissue sodium concentration (TSC) in cardiac Na MRI. To evaluate the influence of different correction methods on the measured myocardial TSC.

Methods: Na MRI of four healthy subjects was conducted at a whole-body 7T MRI system using an oval-shaped Na birdcage coil.