Gastro-oesophageal reflux disease (GORD) is a spectrum of disease that occurs when gastric acid refluxes from the stomach into the lower end of the oesophagus across the lower oesophageal sphincter (LOS).
Minor reflux disease
In most patients with reflux disease, reflux is initiated by transient collapses of LOS pressure. This results in the lower end of the oesophagus being bathed in gastric acid for longer than normal. Patients may be symptomatic without developing endoscopic appearances of oesophagitis (40% of cases). These patients will also have no detectable abnormality on a barium swallow.
Loss of appropriate LOS function gives rise to symptoms of reflux and globus symptoms, e.g. sensation of a lump at the back of the throat. It is affected by anatomical and physiological abnormalities:
- prolonged fundal distension
- sphincter shortening
- repetitive transient LOS pressure collapse
In normal patients, the intra-abdominal oesophagus improves LOS function. However, in patients with hiatus hernia, the amount of intra-abdominal oesophagus is reduced and increases in intra-abdominal pressure are more likely to overcome the LOS pressure and cause reflux.
Advanced reflux disease
In patients with a permanently low LOS pressure, symptoms are generally more severe and there is evidence of disease in endoscopic or barium studies. Abnormalities that are radiologically detectable include:
- free reflux
- impaired primary peristalsis and poor clearance
- abnormal oesophageal contractions
- oesophagitis with scarring
- strictures, Barrett oesophagus and aspiration
- sacculations and intramural pseudodiverticula
Theoretical response to acid
Traditional theories hold that GORD invokes a linear response of severity dependant on exposure to acid. Mild oesophagitis progresses severe ulcerated oesophagitis. This then progresses to Barrett oesophagus and then, in a proportion of patients, dysplasia and eventually cancer develop.
Modern theory suggests that there is no such linear response to acid exposure in the lower osesophagus. Instead, the oesophagus, under the stimulus of excess acid exposure, undergoes change in one of three ways:
- columnal lined oesophagus (metaplastic): short-segment; long-segment; cancer
- reflux oesophagitis (inflammatory): low grade; high grade; peptic stricture
- endoscopically negative GORD: little visible response but have significant symptoms
Treatment and prognosis
- medical treatment in minor cases.
- surgery for advanced and resistant cases; fundoplication is the operation of choice, it can be done endoscopically or open surgery; a fold from the gastric fundus is wrapped around the lower esophageal junction to enforces the action of the sphincter
- oesophageal dysmotility
- oesophageal tumours
- benign oesophageal neoplasms
- malignant oesophageal neoplasms
- gastro-oesophageal reflux disease
- oesophageal stricture
- 1. The Radiology Interactive Training Initiative (RITI), Royal College of Radiologists, UK