The use of MRI to demonstrate small bowel obstruction during pregnancy

Patients who present during pregnancy with acute abdominal symptoms often present a significant diagnostic challenge. Although ultrasound is often the first mode of abdominal imaging, in complex cases further imaging is often necessary. MRI of the small bowel has been made possible with the development of rapid scanning techniques. This has increased the attractiveness of a modality whose benefits include multiplanar imaging, excellent soft tissue contrast and the avoidance of ionizing radiation. With these capabilities MRI has been shown to be a useful adjunct when imaging the small bowel in pregnancy. Although MRI has been employed to investigate small bowel obstruction in the obstetric setting, to date there have been no reports of MR identifying small bowel obstruction secondary to extrinsic compression from a gravid uterus. During pregnancy, small bowel obstruction is most commonly attributed to adhesions. However, there are also antenatal occurrences of small bowel obstruction secondary to uterine compression. We present the MRI findings of an unusual case of small bowel obstruction occurring secondary to compression from a 32-week gravid uterus, in a patient with an end ileostomy. Furthermore, while clinical history and examination are fundamental to diagnosis of intestinal obstruction, the following case highlights the value of MRI in pregnancy as a confirmatory test.