Abstract
The aim of this study was to develop and evaluate a gadolinium - barium sulfate solution for use in both conventional and MR enteroclysis. Eighteen vials of 20% barium sulfate and various gadolinium concentrations (lower 2.5 ml/lt, higher 45 ml/lt) were prepared and placed in the magnet. The imaging protocol was consisted of the following sequences: true FISP, HASTE with fat saturation and 3d FLASH with fat saturation in various flip angles. The lowest gadolinium concentration in the barium sulfate solution generating low intraluminal signal on HASTE and high intraluminal signal on true FISP and 3d FLASH sequences was 15 ml/lt. Ten patients underwent conventional enteroclysis with 1.5 lt of 20% barium sulfate enema and 22.5 ml of gadolinium. MR Enteroclysis was performed afterwards using true FISP, fat suppressed 3d FLASH and fat suppressed HASTE sequences. In all patients the proposed contrast medium acted as positive in 3d FLASH (T1w), true FISP (T2/T1 w) and as a negative in HASTE (T2w). In conclusion, a 20% barium sulfate enema with 15 ml/lt gadolinium is appropriate for conventional and MR Enteroclysis studies.

Keywords: MRI, contrast medium, gadolinium, Crohn's disease, Enteroclysis Text
Introduction
Fast and ultrafast sequences, high performance gradient coils and dedicated abdominal phased array coils resulted in significant improvement in MR Imaging of the small bowel (SB). Resent reports indicated that MRI may be clinically useful for anatomic demonstration, identification and characterization of SB abnormalities, providing information from the bowel lumen - wall and the mesenteries (1-8). However, there is no consensus on the optimum sequences that should be used for SB imaging or on the appropriate contrast media for lumen opacification. In the present study different gadolinium concentrations within a 20%