Upper Gastrointestinal Series with Small Intestine Follow-Through: Current Role in Clinical Practice
Upper gastrointestinal series (UGIS) with small intestine follow-through (SIS) should be discontinued as a routine procedure and only used selectively for specific clinical indications, as it has been largely replaced by more effective imaging modalities.
Current Role of UGIS with Small Intestine Follow-Through
The role of UGIS with small intestine follow-through has significantly diminished in modern clinical practice due to several factors:
When UGIS with SIS is Still Indicated:
Suspected malrotation: UGIS remains the reference standard for evaluating malrotation, with a sensitivity of 96% 1. However, even in this scenario, it has limitations with false-positive rates of 10-15% and false-negative rates of 2-3% 1.
Equivocal UGI findings: When initial UGIS shows equivocal findings for malrotation, small bowel follow-through to the cecum may be pursued for clarification 1.
Pre-surgical planning: In patients with severe GERD requiring surgical intervention (e.g., Nissen fundoplication), UGIS can help exclude anatomic abnormalities like esophageal stricture or malrotation that would need to be addressed during surgery 1.
When UGIS with SIS Should NOT Be Used:
Chronic constipation evaluation: The American College of Radiology explicitly states there are no data supporting the use of UGIS with small bowel follow-through for evaluating chronic constipation 2.
Gastroesophageal reflux diagnosis: UGIS is not useful for diagnosing GER due to poor sensitivity (31-86%) and specificity (21-83%) compared to pH monitoring 1.
Acute gastrointestinal bleeding: Fluoroscopy with barium or iodinated contrast has no role in evaluating acute upper GI bleeding as positive oral contrast obscures active hemorrhage and may interfere with subsequent endoscopy, angiography, or CT 1.
Superior Alternatives to UGIS with SIS
For Upper GI Evaluation:
- Endoscopy: Direct visualization with ability to obtain biopsies and perform therapeutic interventions
- CT with contrast: Higher sensitivity for detecting pathology with cross-sectional imaging
For Small Bowel Evaluation:
- CT enterography: Superior for detecting small bowel pathology, though primarily used for finding potential bleeding sources rather than active bleeding 1
- Capsule endoscopy: Novel approaches like the UMGI capsule endoscopy system provide alternative screening modalities for the upper and mid-GI tract with good diagnostic yield (96.2% sensitivity) 3
Specific Clinical Scenarios
For Suspected Malrotation:
- UGIS remains first-line imaging
- Ultrasound can be complementary (whirlpool sign is specific for volvulus) 1
- If UGIS is equivocal, small bowel follow-through to the cecum may be pursued 1
For Small Bowel Obstruction:
- Gastrografin SBFT can be valuable in management, leading to shorter time to operative intervention (1.0 vs 3.7 days) and faster resolution with non-operative management (1.8 vs 4.7 days) 4
For Bariatric Surgery Patients:
- Selective rather than routine UGIS after laparoscopic Roux-en-Y gastric bypass has been shown to reduce hospital stay without adversely affecting morbidity or mortality 5
Pitfalls and Caveats
- Radiation exposure: UGIS with small bowel follow-through exposes patients to ionizing radiation, which is particularly concerning for pregnant patients and young individuals
- Limited diagnostic yield: For many conditions, the diagnostic yield is inferior to newer imaging modalities
- Potential interference: Barium studies may interfere with subsequent imaging or endoscopic procedures
- Time-consuming: SBFT can be lengthy, requiring multiple images over time to track contrast through the small intestine
Conclusion
While UGIS with small intestine follow-through still has select indications (primarily for suspected malrotation), it should no longer be used routinely due to the availability of superior diagnostic modalities with better sensitivity, specificity, and reduced radiation exposure. Clinicians should select the most appropriate imaging study based on the specific clinical question, with UGIS with SIS reserved for particular scenarios where it offers unique diagnostic value.