GI Studies
39 Esophagus
Anatomy
- Mouth
- Pharynx
- Esophagus
- Stomach
- Esophagogastric junction
- Cardiac antrum
Indications, Contraindications, and Patient Preparation
Indications
- Anatomical anomalies (e.g., birth defects, strictures)
- Foreign body obstruction
- Esophageal reflux (GERD)
- Esophageal varices (dilated veins in the esophagus)
- Motility disorders
Contraindications
- No absolute contraindications
- Do not use barium sulfate if recent surgery or suspected perforation → substitute water-soluble iodinated contrast (e.g., Gastrografin)
Patient Preparation
- No prep required if esophagram only
- If combined with Upper GI: patient should be NPO for at least 8 hours
- Always check for contrast allergies: iodine, seafood, x-ray dye if iodinated contrast will be used
Projections
PA or AP Esophagus
CR Location & Positioning
- SID: 40 inches
- Patient position: Supine or upright; MSP centered to IR
- Adjustments: Arms down at sides, shoulders level
- CR: Perpendicular to IR, centered at level of T5–T6 (≈ 3″ below jugular notch)
- Pt. Instructions: “Drink, drink, drink…” (Swallow contrast while exposure is made)
- Exposure: During swallowing
Evaluation Criteria
- Entire esophagus filled with barium
- No body rotation (SC joints symmetric)
RAO Esophagus
CR Location & Positioning
- SID: 40 inches
- Patient position: Prone, rotated 35–40° into RAO
- Adjustments: Right arm down, left arm flexed at elbow, head turned slightly toward IR
- CR: Perpendicular to IR, centered at T5–T6 (3″ below jugular notch)
- Pt. Instructions: “Drink, drink, drink…” (Swallow contrast while exposure is made)
- Exposure: During swallowing
Evaluation Criteria
- Esophagus projected between spine and heart
- Entire esophagus filled with contrast
- Arms not obscuring field
Lateral Esophagus
CR Location & Positioning
- SID: 40 inches
- Patient position: True lateral, MCP centered to IR
- Adjustments: Arms raised forward to avoid superimposition
- CR: Perpendicular to IR, centered at T5–T6
- Pt. Instructions: “Drink, drink, drink…” (Swallow contrast while exposure is made)
- Exposure: During swallowing
Evaluation Criteria
- Esophagus seen between spine and heart shadow
- Posterior ribs superimposed (true lateral)
- Entire esophagus filled with contrast
LAO Esophagus (Optional)
CR Location & Positioning
- SID: 40 inches
- Patient position: Prone, rotated 35–40° into LAO
- Adjustments: Left arm down, right arm up across chest
- CR: Perpendicular to IR, centered at T5–T6
- Pt. Instructions: “Drink, drink, drink…” (Swallow contrast while exposure is made)
- Exposure: During swallowing
Evaluation Criteria
- Esophagus projected between hilar region and T-spine
- Entire esophagus filled with contrast
- Arms not superimposing field
Procedure Adaptation
- Preferred oblique: RAO → provides better visualization of esophagus between spine and heart compared to LAO.
- Pediatrics: Smaller volumes of contrast; may require immobilization.
- Trauma / immobile patients: AP supine with horizontal beam.
- Motility studies: Multiple swallows may be recorded to evaluate peristalsis.
Exposure Factors & Technical Considerations
- SID: 40 inches
- kVp: 100–110 for single contrast; 90–100 for double contrast
- mAs: Low, short exposures to freeze swallowing motion
- Collimation: Include entire esophagus from oropharynx to stomach
- Contrast:
- Positive contrast → barium sulfate
- Negative contrast → air (effervescent crystals)
- Shielding: Gonadal shielding when possible
Hows & Whys of Esophagus Radiography
Anatomy & Function
- What are the boundaries of the oral cavity?
The teeth, hard and soft palates, and tongue. - What is the medical term for chewing?
Mastication. - What is the medical term for swallowing?
Deglutition. - Where does the oral cavity connect posteriorly?
To the pharynx. - At what level does the pharynx transition into the esophagus?
C6. - Where are the indentations of the esophagus located?
At the aortic arch and where it crosses the left primary bronchus. - What is the esophageal hiatus, and at what level is it located?
An opening in the diaphragm where the esophagus passes through at T10. - What is the cardiac antrum?
The portion of the esophagus below the diaphragm, just before it joins the stomach. - Where does the esophagus join the stomach, and what is this opening called?
At the esophagogastric junction, also called the cardiac orifice, at level T11.
Contrast & Technique
- What types of contrast media are used in an esophagram?
Positive (radio-opaque, e.g., barium sulfate) and negative (radiolucent, e.g., air from gas crystals). - What is positive contrast?
Material that appears white on images, such as barium or iodinated agents. - What is negative contrast?
Material that appears black on images, such as air. - Who performs the fluoroscopy during an esophagram?
The radiologist, with the technologist assisting the patient. - Why is the RAO position usually preferred over the LAO position?
It places the esophagus between the spine and heart, giving the clearest visualization. - What is the Valsalva maneuver?
Forcing exhalation against a closed glottis, as if straining to have a bowel movement. - What does the Valsalva maneuver demonstrate?
Increases intra-abdominal and thoracic pressure, which may demonstrate esophageal reflux.
Indications & Safety
- What are the common indications for an esophagram?
Anomalies, foreign body obstruction, reflux, esophageal varices, motility disorders. - Are there any contraindications to an esophagram?
No major ones. Avoid barium sulfate if perforation is suspected or after recent surgery. - When might water-soluble contrast be used instead of barium?
When perforation or post-surgical leakage is suspected. - What allergies should be checked if water-soluble contrast is used?
Iodine, seafood, “x-ray dye.” - Is there any special preparation before an esophagram?
No preparation unless combined with an Upper GI study (then patient must be NPO for 8 hours).