[Modern, minimally invasive surgery of the lacrimal duct system].

Epiphora (tearing) is the main symptom of a dysfunction of the lacrimal drainage. Tearing is a common problem and the cause can not easily be identified. Since development and miniaturisation of gastroduodenal endoscopes in the 1990s, it is possible to check the anatomical structure and the pathological changes of the lacrimal drainage system, which has a diameter of 1 mm. Mechanical stenosis is often caused by recurring chronic inflammation. Complete stenosis is usually only punctual and seldom over a long distance. Shortly after the development of microendoscopic diagnostic tools, therapeutic techniques using a laser for the dacryoplasty (LDP) or a microdrill for the dacryoplasty (MDP) were established. For the first time, these treatments enable preservation of the whole physiology of the lacrimal drainage system in spite of surgical intervention.