Examination of the Lipid Metabolism of the Liver After Choline Substitution in Cystic Fibrosis

Inclusion Criteria: * Age \> 18 years * male * Cystic fibrosis is verified * pancreatic insufficiency * Decline of plasma phosphatidylcholine and steatosis of the liver * informed consent is given Exclusion Criteria: * cirrhosis of the liver * Hyperreactivity to choline containing food * allergic bronchopulmonary aspergillosis or other acute exacerbations of pulmonary infections * FEV1 \< 40% * smoker * chronic alcohol consume * clinically relevant diseases (for example thyroid dysfunction, disturbance of lipid metabolism, renal diseases, significant left or right ventricular functional restriction) which will change the lipid metabolism of the liver * Implants or other reasons which make magnetic resonance examinations impossible