What are the recommended diagnostic procedures and treatment options for a hiatal hernia?

Diagnostic Approach to Hiatal Hernia

The biphasic esophagram (combining double-contrast and single-contrast barium studies) is the recommended initial diagnostic test for hiatal hernia, achieving 88% sensitivity and providing both anatomic and functional information about the esophagus and gastroesophageal junction. 1

Primary Diagnostic Imaging

First-Line: Fluoroscopic Studies

• Biphasic esophagram is superior to single imaging techniques, combining double-contrast views (optimizing detection of inflammatory conditions) with single-contrast views (optimizing detection of hiatal hernias and esophageal rings/strictures). 1
• The double-contrast upper GI series alone achieves 80% sensitivity for detecting associated esophagitis and is particularly beneficial for evaluating structural and functional abnormalities of the esophagus, stomach, and duodenum. 1
• Single-contrast esophagram may miss mucosal irregularities from reflux disease and should not be used as the sole imaging modality. 2
• All patients being considered for antireflux surgery must undergo barium esophagogram according to the American College of Surgeons' Esophageal Diagnostic Advisory Panel. 1

When to Add Upper GI Series

• For large hiatal hernias, include a complete upper GI series to fully evaluate the stomach anatomy and position. 1, 3
• This provides critical information about esophageal length, presence of strictures, and gastroesophageal reflux. 2

Secondary Diagnostic Methods

CT Scanning: When and Why

• CT scan is the gold standard for diagnosing complicated diaphragmatic hernias, with 87% specificity, and should be used when complications are suspected (volvulus, ischemia, strangulation). 1, 2
• CT with IV contrast is superior for determining the presence, location, and size of diaphragmatic defects when chest X-ray findings are inconclusive but clinical suspicion remains high. 1
• Key CT findings indicating complications include: absence of gastric wall contrast enhancement, intestinal wall thickening with target enhancement, diaphragmatic discontinuity, "collar sign," and "dependent viscera" sign. 2
• Critical caveat: Normal chest radiographs occur in 11-62% of diaphragmatic hernias, so negative plain films do not exclude the diagnosis. 1, 2

Endoscopy: Role and Limitations

• Endoscopy is essential for evaluating esophagitis erosiva, esophageal strictures, and differentiating other pathologies like eosinophilic esophagitis. 3
• Endoscopy has higher sensitivity (67%) than high-resolution manometry (52%) for detecting hiatal hernias, but lower specificity (68% versus 95%). 4
• Endoscopy produces more false positives (31.71%) compared to high-resolution manometry (4.88%). 4
• Both endoscopy and manometry have high false-negative rates (45-48%), making negative results unreliable for ruling out hiatal hernia. 4

Manometry: Limited Diagnostic Value

• Esophageal manometry has only 20% sensitivity for detecting hiatal hernias compared to endoscopy, though specificity is 99%. 5
• High-resolution manometry (defining hiatal hernia as >2 cm separation between gastroesophageal junction and crural diaphragm) has better specificity than endoscopy but similar poor sensitivity. 4
• Manometry does not provide diagnostic value as a primary test for hiatal hernia; its role is limited to assessing esophageal peristalsis in preoperative planning. 6

Diagnostic Algorithm

Step 1: Initial Evaluation

• Order biphasic esophagram/double-contrast upper GI series as the first imaging study for suspected hiatal hernia. 1, 3
• Include complete upper GI series if a large hernia is suspected based on symptoms (significant dysphagia, early satiety, chest discomfort). 1, 3

Step 2: If Fluoroscopy is Inconclusive or Complications Suspected

• Obtain CT chest and abdomen with IV contrast if clinical suspicion remains high despite negative or equivocal fluoroscopic studies. 1, 2
• CT is mandatory if symptoms suggest complications: acute chest pain, vomiting suggesting volvulus, signs of gastric ischemia. 2

Step 3: Endoscopy for Treatment Planning

• Perform upper endoscopy to evaluate for reflux esophagitis, Barrett's esophagus, strictures, and to rule out eosinophilic esophagitis. 3
• Endoscopy is required before considering antireflux surgery to assess mucosal damage. 3

Step 4: Special Populations

• In pregnant patients, use ultrasonography first, followed by MRI if necessary, to avoid radiation exposure. 2
• In post-bariatric surgery patients with suspected internal hernia, contrast-enhanced CT with both oral and IV contrast is mandatory. 2

Common Pitfalls to Avoid

• Do not order CT as first-line imaging for uncomplicated hiatal hernia when fluoroscopic studies are more appropriate and informative. 2
• Do not rely on chest X-ray alone—it misses 11-62% of diaphragmatic hernias. 1, 2
• Do not use non-contrast CT when evaluating potential vascular complications or relationship to cardiac structures. 2
• Do not assume a negative endoscopy or manometry rules out hiatal hernia—both have false-negative rates approaching 50%. 4
• Do not skip barium esophagogram in patients being considered for antireflux surgery, regardless of other imaging findings. 1