1 Unit of Digestive Radiology (First Surgery University Clinic), Center of Radiology and MR, Clinical Center of Serbia, Koste Todorovica 6, Beograd, 11000, Serbia.
2 Unit of Digestive Radiology (First Surgery University Clinic), Center of Radiology and MR, Clinical Center of Serbia, Koste Todorovica 6, Beograd, 11000, Serbia. avstefan@eunet.rs.
3 Faculty of Medicine, University of Belgrade, Belgrade, Serbia. avstefan@eunet.rs.