MR imaging of the small bowel using the HASTE sequence

OBJECTIVE. To establish the normal MR appearance of small bowel on half-Fourier acquisition single-shot turbo spin-echo (HASTE) sequence and to determine the ability of HASTE to reveal small-bowel disease. MATERIALS AND METHODS. HASTE images in 50 patients without small-bowel disease were reviewed retrospectively to determine the normal MR appearance of small bowel. All patients fasted for at least 6 hr. The images of 18 patients with proven small-bowel abnormalities that were obtained with the HASTE sequence were also reviewed retrospectively by one observer unaware of the findings. The ability to characterize small-bowel diseases using the HASTE sequence was assessed. RESULTS. In the 50 patients with normal small bowel, no fluid was seen in the jejunum and ileum loops in four (8%). Fluid was present in less than 25% of small-bowel loops in 20 patients (40%), 25-50% of small-bowel loops in 20 patients (40%), and 50-75% of small-bowel loops in six patients (12%). Equal amounts of fluid were present in the jejunum and ileum in 30 patients (60%). More fluid was seen in the jejunum than the ileum in 16 patients (32%) and the reverse was true in four patients (8%). The mean diameter of the jejunum was 2.1 cm (SD = 0.34 cm) and of the ileum, 1.9 cm (SD = 0.41 cm), The thickness of the small-bowel wall and valvulae conniventes averaged 2 mm. Findings of dilatation of the bowel lumen and increased thickness of the bowel wall and valvulae conniventes were identified in 18 patients with small-bowel abnormalities. CONCLUSION. The normal and abnormal small bowel can be assessed using the HASTE sequence.