Simon Konstandin

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Sodium accumulation is involved in neuronal injury occurring in multiple sclerosis (MS). We aimed to assess sodium accumulation in progressive MS, known to suffer from severe neuronal injury. 3D-23Na-MRI was obtained on a 3T-MR-scanner in 20 progressive MS patients [11 primary-progressive (PPMS) and nine secondary-progressive (SPMS)] and 15 controls. Total(More)
PURPOSE To quantify brain sodium accumulations and characterize for the first time the spatial location of sodium abnormalities at different stages of relapsing-remitting (RR) multiple sclerosis (MS) by using sodium 23 ((23)Na) magnetic resonance (MR) imaging. MATERIALS AND METHODS This study was approved by the local committee on ethics, and written(More)
PURPOSE To qualitatively and quantitatively assess the corticomedullary sodium 23 ((23)Na) concentration in human kidneys before and after oral administration of a water load by using 3-T magnetic resonance (MR) imaging. MATERIALS AND METHODS Fourteen healthy volunteers (mean age, 28 years; range, 24-34 years) were included in this institutional review(More)
The purpose of this prospective study was to assess the normal physiologic ranges of the renal corticomedullary 23Na-concentration ([23Na]) gradient at 3.0T in healthy volunteers. The corticomedullary [23Na] gradient was correlated with other functional MR imaging parameters—blood oxygenation level dependent (BOLD) and diffusion-weighted imaging (DWI)—and(More)
BACKGROUND CONTEXT 1H magnetic resonance imaging (MRI) of the spine can rule out common causes of low back pain (LBP), such as disc protrusions or nerve root compression; however, no significant causal relation exists between morphology and the extent of symptoms. Functional MRI techniques, such as 23Na, may provide additional information, allowing indirect(More)
Sodium magnetic resonance imaging ((23)Na MRI) is a unique and non-invasive imaging technique which provides important information on cellular level about the tissue of the human body. Several applications for (23)Na MRI were investigated with regard to the examination of the tissue viability and functionality for example in the brain, the heart or the(More)
PURPOSE 23Na-MRI has been proposed as a potential imaging biomarker for the assessment of tumor viability and the evaluation of therapy response but has not yet been evaluated in patients with lung cancer. We aimed to assess the feasibility of 23Na-MRI in patients with lung cancer. MATERIALS AND METHODS Three patients with stage IV adenocarcinoma of the(More)
Sampling density-weighted apodization projection reconstruction sequences are evaluated for three-dimensional radial imaging. The readout gradients of the sampling density-weighted apodization sequence are designed such that the locally averaged sampling density matches a Hamming filter function. This technique is compared with density-adapted projection(More)
Sodium magnetic resonance imaging (²³Na MRI) is a non-invasive technique which allows spatial resolution of the tissue sodium concentration (TSC) in the human body. TSC measurements could potentially serve to monitor early treatment success of chemotherapy on patients who suffer from whole body metastases. Yet, the acquisition of whole body sodium (²³Na)(More)
BACKGROUND Established imaging methods are still not confident in the determination of stroke onset. Sodium imaging in animal models and lately in humans implicates that the sodium signal intensity within the ischemic lesion increases in a time-dependent fashion. Sodium imaging usually requires a time-consuming change of resonators or magnetic resonance(More)