214 THE LARYNX, BRONCHI AND OESOPHAGUS exist, namely, perforation by foreign body, excessive vomiting, surgical trauma, and erosion by caustics or drugs, but the commonest cause is oesophagoscopy. The perforation may be in the cervical oesophagus or the thoracic oeso- phagus and it is important to distinguish these in the management of the condition. Perforation of the cervical oesophagus may be caused by trying to force a way through cricopharyngeus thus creating a false passage posteriorly (through the weak area), or by entering a pharyngeal pouch instead of the oesophagus and attempting to force a way through it. In the thoracic oesophagus perforations are most likely to occur by attempting to dilate a benign or malignant stricture, or by taking too deep a biopsy of a carcinoma or an oesophagitis. Rough attempts at removal of sharp foreign bodies can also perforate the oesophagus. DIAGNOSIS. The symptoms manifest themselves within a few hours of the procedure. There is pain in the back between the shoulder blades and also painful dysphagia. After a short time the temperature rises rapidly to around 39 °C and surgical emphysema is palpable. Radiography shows a broadened mediastinum and if Dionosil is swallowed, the site of the perforation may be seen. TREATMENT. At whatever stage the diagnosis is made a nasogastric tube should be passed, all oral feeding stopped, broad-spectrum antibiotics started and half-hourly vital sign charts commenced. If the diagnosis is made in the first 24 hours the neck or the chest should be opened, the perforation closed surgically and the wound drained. If the diagnosis is delayed, the edges of the perforation become necrotic, surgical closure is less certain and a conservative line of treatment is more likely to be successful. It is in this group that the mortality is high.