Normal Upper GI Series Results
A normal upper GI series demonstrates the duodenojejunal junction (ligament of Treitz) positioned to the left of midline at approximately the level of the duodenal bulb, with the duodenum crossing the midline and coursing in a normal C-shaped configuration around the pancreatic head. 1
Key Anatomic Landmarks in a Normal Study
The upper GI series evaluates the esophagus, stomach, pylorus, and duodenum through the duodenojejunal junction 1. Normal findings include:
Duodenal position: The duodenum should demonstrate a normal C-loop configuration with the third portion passing behind the superior mesenteric artery (SMA), and the duodenojejunal junction (ligament of Treitz) positioned to the left of the vertebral column at approximately the level of the duodenal bulb 1
Esophageal appearance: Smooth mucosal surface without nodularity, erosions, ulcers, thickened folds, strictures, or masses 1. The esophagus should demonstrate normal peristaltic activity and appropriate passage of contrast 1
Gastric findings: Normal areae gastricae pattern (polygonal mucosal pattern), smooth gastric folds without thickening, nodularity, or mass effect 1. No evidence of ulceration or filling defects 1
Pylorus and duodenal bulb: Patent pyloric channel with normal passage of contrast, smooth duodenal bulb without deformity or ulceration 1
Technical Considerations
Meticulous technique is essential, as redundant duodenum, bowel distension, and variable jejunal position can lead to false-positive or false-negative interpretations 1. Studies have documented false-positive rates of 10-15% and false-negative rates of 2-4% even for experienced interpreters 1.
What a Normal Study Excludes
A technically adequate normal upper GI series effectively excludes:
Malrotation: The most critical diagnosis to exclude, particularly in infants with bilious vomiting, though sensitivity is 96% with potential for both false-positives and false-negatives 1
Structural abnormalities: Including hiatal hernia (when adequately evaluated), esophageal strictures, gastric outlet obstruction, and duodenal webs or stenosis 1
Ulcer disease: Though small or superficial ulcers may be missed, particularly on single-contrast technique 1
Critical Limitations to Recognize
Gastroesophageal reflux cannot be reliably diagnosed or excluded by upper GI series due to the brief examination duration and high rate of physiologic reflux 1. Sensitivity ranges from only 31-86% and specificity from 21-83% compared to pH monitoring 1
Early mucosal disease may be missed without double-contrast technique, which achieves 80-88% sensitivity for esophagitis compared to 77% for single-contrast 1
Mobile cecum occurs in up to 15% of normal individuals, which can complicate interpretation when malrotation is suspected 1