Is oral contrast required?

Oral contrast can be helpful in abdominal and pelvic CT. Its increased density defines bowel loops, can identify intrinsic bowel masses or site of leaks. Because of the lack of mesenteric fat, it can be particularly useful in thin patients.

However, the use of oral contrast adds time to the study. Patients must drink contrast 1-2 hours prior to the CT exam. In patients with bowel obstruction, often the oral contrast may never reach the site of obstruction.

Oral contrast can interfere with 3D reconstructions of CT angiograms or bone studies. For this reason, we may use water ingested just prior to the scan as a "negative" oral contrast agent in CTA, multiphase study of solid organs, mesenteric ischemia studies or pelvic fracture assessments.

Oral contrast CAN be ordered for any abdominal/pelvic CT. Allergies are very rare and in general oral contrast will not harm the patient.