Pathogenesis and endoscopic treatment of the hypopharyngeal (Zenker's) diverticulum.

The authors review the literature about the pathogenesis -still unknown- of Zenker's diverticulum as well as their experience of endoscopic treatment of this disease. From 1964 till 1988, they have treated endoscopically 507 patients, 323 by electrocoagulation, 184 by CO2-laser. The endoscopic procedure is described, consisting in precise division of the tissue bridge between the oesophagus and the diverticulum by micro-endoscopic surgery under general anesthesia. In recent years, the CO2-laser was found preferable, since it may cause less tissue necrosis and consequently less fibrous scar tissue. The results were very favourable, with more than 99% of the patients satisfied. Although many patients were old and in poor condition, only one patient died two days after operation because of cardiac failure. Complications such as bleeding, emphysema, mediastinitis and stenosis were seen in 5% of the patients, but in most cases there complications were mild and conservative therapy was sufficient. Stenosis occurred in 8 patients treated by electrocoagulation and in none of the patients treated by laser. Microendoscopic surgery is a safe and efficient method of therapy for the hypopharyngeal diverticulum.