Gastrointestinal tract labeling for MDCT of abdomen: comparison of low density barium and low density barium in combination with water.

The purpose of the study was to compare the quality of stomach and small bowel marking/labeling using 1,350 ml of low-density barium alone (VoLumen) with 900 ml of low-density barium and 450 ml of water for 16-MDCT scans of the abdomen and pelvis and assess cost benefits with the two protocols. In this IRB approved study, 80 consecutive patients scheduled for routine CECT (contrast-enhanced CT) of the abdomen-pelvis were studied. Patients were randomized into two groups and were administered either 1,350 ml of VoLumen (two bottles at 20-min intervals, one half bottle at 50 min and the last half on the table) or 900 ml of VoLumen (two bottles at 20-min intervals and 450 ml water on the table). Portal venous phase scanning (detector collimation=0.625 mm, speed=18.75 mm, thickness=5 mm) was subsequently performed. Images were reconstructed in axial and coronal plane at the CT console. Two blinded readers used a pre-designed template to assess distension and wall characteristics of the stomach and small bowel on a 5-point scale. Median scores with the two protocols were compared using the Wilcoxon rank sum test. The stomach and small bowel labeling was rated fair to optimal in all patients and did not differ significantly in the two protocols. The mean scores for distension of the small bowel and stomach were comparable. Inter-observer agreement for bowel labeling was found to be excellent (k 0.81). With the use of coronal images there was increased reader confidence in tracing the small bowel with both protocols. Acceptance for two bottles of VoLumen and water was greater among patients as compared to three bottles of VoLumen. Use of two bottles of VoLumen and water combination cost less than three bottles of VoLumen. Stomach and small bowel labeling with administration of 900 ml of VoLumen followed by 450 ml of water is cost effective and compares well to 1,350 ml of VoLumen alone.