Diagnostic modalities of oesophageal disease
Investigations for gastroesophageal reflux disease
Many modalities may be used in gastroesophageal reflux disease:
- Upper endoscopy
- Oesophageal pH monitoring
- Oesophageal impedance
- Bilitec®
Oesophageal pH monitoring
Oesophageal pH can be monitored by a probe or wireless capsule placed in the stomach near the lower oesophagus for 24 hours, allowing measurement of acid in the distal oesophagus.
Oesophageal impedance
Oesophageal impedance measures the flow of reflux into the oesophagus. It works on the principle of measuring impedance (resistance to electrical flow). It can measure reflux of gas and liquid, not only pH. It’s often measured simultaneously as pH monitoring detailed above with the same device.
Bilitec
Bilitec® detects bilirubin in the oesophagus and is a test for biliary reflux.
Investigations for oesophageal motility disorders
These investigations are used for the diagnosis of oesophageal motility disorders like achalasia or diffuse oesophageal spasm.
- Oesophageal manometry
- Barium swallow
Oesophageal manometry
Manometry is the gold standard for diagnosis of motility disorders. It uses a transnasal catheter with pressure sensors to analyse pressure at different points in the oesophagus, allowing analysis of the peristaltic waves in the oesophagus.
Barium swallow
Barium swallow, also called an oesophagogram, involves making the patient swallow barium contrast while the oesophagus is imaged by fluoroscopy. This allows visualisation of food moving through the oesophagus in real time.
Investigations for oesophageal cancer
The diagnosis of oesophageal cancer is histologic, and a biopsy is obtained by upper endoscopy (oesophagoscopy).
CT and PET-CT are also important in the evaluation of oesophageal cancer but somewhat out of the scope of the topic.