[1] Univ Med Ctr Gottingen, Dept Diagnost & Intervent Radiol, D-37075 Gottingen, Germany
[2] Univ Med Ctr Gottingen, Dept Gastroenterol & Gastrointestinal Oncol, Gottingen, Germany
[3] Univ Med Ctr, Dept Gen Visceral & Paediat Surg, Gottingen, Germany
[4] Max Planck Inst Biophys Chem, Biomed NMR, Gottingen, Germany