From the Guidelines
CT enterography with oral contrast is the preferred imaging modality for evaluating recurrent small bowel obstruction (SBO), as it provides optimal distension of the small bowel and detection of bowel pathology. This recommendation is based on the American College of Radiology (ACR) Appropriateness Criteria for suspected small-bowel obstruction, which suggests that CT enterography has greater patient acceptance and can optimize detection of bowel pathology 1. The use of oral contrast ingestion protocol in CT enterography increases distention of the small bowel, potentially benefiting the identification of intermittent or low-grade SBO.
When performing CT enterography for recurrent SBO, the following protocol is recommended:
- Oral contrast (typically a neutral contrast agent like VoLumen or water) should be administered to distend the bowel, improving visualization of the intestinal lumen and wall.
- IV contrast should also be administered unless contraindicated, as it enhances the bowel wall and mesentery, helping to identify inflammation, ischemia, or neoplasms.
- The typical protocol involves having the patient drink 1-1.5 liters of oral contrast over 45-60 minutes before scanning, followed by IV contrast administration immediately before imaging.
The advantages of CT enterography over standard CT with contrast for recurrent SBO include:
- Better distension of the small bowel loops, allowing for more accurate assessment of partial obstructions and subtle lesions.
- Improved detection of subtle abnormalities like Crohn's disease, radiation enteritis, or small tumors that may be causing intermittent obstructions.
- Greater patient acceptance due to the non-invasive nature of the procedure.
Overall, CT enterography with oral contrast is a valuable diagnostic tool for evaluating recurrent SBO, particularly in patients with recurrent symptoms where the cause remains elusive after standard workup 1.
From the Research
CT Enterorrhaphy with or without Contrast for Recurrent SBO
- The use of CT enterorrhaphy with or without contrast for recurrent small bowel obstruction (SBO) has been evaluated in several studies 2, 3, 4, 5, 6.
- A study from 1999 found that computed tomography (CT) was superior to small bowel follow-through in identifying masses, malignancies, and features of strangulation in patients with SBO 2.
- A 2019 study compared the sensitivity of unenhanced CT and contrast-enhanced CT for identifying the etiology of bowel obstruction, and found that sensitivity was not significantly different between the two methods 3.
- Another study from 2019 provided evidence-based recommendations for the evaluation and management of SBO in the emergency department, including the use of CT and ultrasound for diagnosis 4.
- A 2015 study outlined a practical step-by-step approach to evaluating and managing SBO, including the use of CT and Gastrografin to efficiently sort patients into those who will resolve their obstructions and those who will fail nonoperative management 5.
- A 2023 study found that operative intervention was associated with a statistically significant decrease in recurrence rates of SBO within one year of presentation, but found no significant difference in recurrences with the use of small bowel follow-through (SBFT) 6.
Key Findings
- CT enterorrhaphy with or without contrast can be used to diagnose and manage recurrent SBO 2, 3, 4, 5.
- The use of contrast may not be necessary in all cases, particularly when the etiology of the obstruction is already known or when the patient has a normal bowel wall thickness 3.
- Operative intervention is associated with a decrease in recurrence rates of SBO 6.
- SBFT may not be effective in reducing recurrence rates of SBO 6.