Metabolic MRI With Hyperpolarized 13 C-Pyruvate for Early Detection of Fibrogenic Kidney Metabolism.

Objectives: Fibrosis is the final common pathway for chronic kidney disease and the best predictor for disease progression. Besides invasive biopsies, biomarkers for its detection are lacking. To address this, we used hyperpolarized 13 C-pyruvate MRI to detect the metabolic changes associated with fibrogenic activity of myofibroblasts.

A Framework for Predicting X-Nuclei Transmitter Gain Using H Signal.

Commercial human MR scanners are optimised for proton imaging, containing sophisticated prescan algorithms with setting parameters such as RF transmit gain and power. These are not optimal for X-nuclear application and are challenging to apply to hyperpolarised experiments, where the non-renewable magnetisation signal changes during the experiment. We hypothesised that, despite the complex and inherently nonlinear electrodynamic physics underlying coil loading and spatial variation, simple linear regression would be sufficient to accurately predict X-nuclear transmit gain based on concomitantly acquired data from the proton body coil.

Daytime Variation in Kidney Perfusion, Oxygenation, and Sodium Concentration Assessed by Multiparametric MRI in Healthy Volunteers.

Background: MRI can provide information on kidney structure, perfusion, and oxygenation. Furthermore, it allows for the assessment of kidney sodium concentrations and handling, allowing multiparametric evaluation of kidney physiology. Multiparametric MRI is promising for establishing prognosis and monitoring treatment responses in kidney diseases, but its intraindividual variation during the day is unresolved.

Considering whole-body metabolism in hyperpolarized MRI through C breath analysis-An alternative way to quantification and normalization?

Purpose: Hyperpolarized [1- C]pyruvate MRI is an emerging clinical tool for metabolic imaging. It has the potential for absolute quantitative metabolic imaging. However, the method itself is not quantitative, limiting comparison of images across both time and between individuals.

Gadolinium-enhanced MRI visualizing backflow at increasing intra-renal pressure in a porcine model.

Introduction: Intrarenal backflow (IRB) is known to occur at increased intrarenal pressure (IRP). Irrigation during ureteroscopy increases IRP. Complications such as sepsis is more frequent after prolonged high-pressure ureteroscopy.

Fibrosis imaging with multiparametric proton and sodium MRI in pig injury models.

Chronic kidney disease (CKD) is common and has huge implications for health and mortality. It is aggravated by intrarenal fibrosis, but the assessment of fibrosis is limited to kidney biopsies, which carry a risk of complications and sampling errors. This calls for a noninvasive modality for diagnosing and staging intrarenal fibrosis.

Lactate saturation limits bicarbonate detection in hyperpolarized C-pyruvate MRI of the brain.

Purpose: To investigate the potential effects of [1- C]lactate RF saturation pulses on [ C]bicarbonate detection in hyperpolarized [1- C]pyruvate MRI of the brain.

Methods: Thirteen healthy rats underwent MRI with hyperpolarized [1- C]pyruvate of either the brain (n = 8) or the kidneys, heart, and liver (n = 5). Dynamic, metabolite-selective imaging was used in a cross-over experiment in which [1- C]lactate was excited with either 0° or 90° flip angles.