1Division of Endocrinology and Metabolism, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria, 2MR Center of Excellence, Medical University of Vienna, Vienna, Austria, 3Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria, 4High-Field MR Center, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria, 5Christian Doppler Laboratory for Clinical Molecular MR Imaging, Medical University of Vienna, Vienna, Austria