Introduction
This topic covers the main benign and malignant diseases of the oesophagus that a radiologist meets: oesophageal diverticula, achalasia, oesophageal tumours, corrosive oesophagitis and oesophageal varices. For each, the answer should give the definition, the mechanism, the typical imaging findings, the key differentials, the complications and the treatment direction, with the role of endoscopy and other tests made clear.
Oesophageal diverticula
A diverticulum is a saccular outpouching or dilation of the oesophageal wall; it is often without symptoms and appears as a white dot on X-ray. Two mechanisms: pulsion (e.g. Zenker's diverticulum at the border between hypopharynx and oesophagus, which has no muscle coat, a pseudodiverticulum) and traction (a true diverticulum in the mid-oesophagus, involving all layers and with a pull). The three main types differ in location and cause.
- Zenker (pharyngo-oesophageal) diverticulum: posterior hypopharyngeal herniation through Killian's dehiscence, caused by cricopharyngeal dysfunction with raised intraluminal pressure; typically in older adults, on the left posterolateral wall.
- Mid-thoracic (traction) diverticulum: pulled out by adhesions to mediastinal lymph nodes, classically from old tuberculosis or granulomatous disease; now rare.
- Epiphrenic diverticulum: distal, just above the diaphragm, usually pulsion, and strongly associated with an underlying motility disorder such as achalasia or spasm.
Imaging: barium swallow with lateral and oblique views is the key test. It shows a contrast-filled sac that may contain an air-fluid level and retains barium after the rest of the oesophagus has emptied. In Zenker disease the sac is seen at the upper oesophagus, and it can cause regurgitation of food, halitosis and aspiration. Complications include aspiration pneumonia, food retention, and rarely perforation or malignant change. Treatment is surgical (cricopharyngeal myotomy with diverticulectomy or diverticulopexy) for symptomatic cases; asymptomatic small diverticula are watched.