Introduction
This topic covers two groups of gastric disease seen on imaging: hiatal hernia, a displacement of abdominal structures through the oesophageal hiatus of the diaphragm, and the benign and malignant tumours of the stomach. For each, the answer should give the definition, classification, mechanism, clinical picture, the radiological and endoscopic signs, complications and the main treatment principles.
Hiatal hernia: definition and types
A hiatal hernia is the protrusion of part of the stomach, or of other abdominal organs, through the oesophageal hiatus into the thorax. The hiatus is normally closed around the oesophagus by the muscular fibres of the right crus of the diaphragm, and weakening of this sphincteric mechanism is the basis of the disease. Hernias are classified by the anatomical relation of the gastro-oesophageal junction and the herniated stomach.
Causes, mechanism and clinical picture
- Predisposing factors: increasing age, female sex, obesity, pregnancy, chronic cough, straining, and raised intra-abdominal pressure.
- Mechanism: a widened hiatus and a weak phrenoesophageal membrane allow the stomach to move upwards, and the lower oesophageal sphincter is displaced so that gastro-oesophageal reflux becomes more frequent.
- Symptoms of sliding hernia: heartburn, regurgitation, retrosternal burning, and sometimes dysphagia or chronic cough; many patients have few symptoms.
- Symptoms of paraoesophageal hernia: postprandial fullness, epigastric pain, early satiety, and anaemia from chronic blood loss (Cameron lesions); acute pain, vomiting and inability to pass a nasogastric tube suggest incarceration.