Endoscopically controlled trocar and cannula insertion.

One of the keys to safe laparoscopic or thoracoscopic surgery is an expeditious and reliable access to the region of interest. To minimise the risk of accidental injury to major vessels, lung, intestine and other important structures the principle of controlled visualised access has been advocated. This has led to several developments in the field of trocars, cannulae and puncture techniques. Examples are the insertion of a needle scope into a Veress needle, complex access cannulae and our new principle of using an "optical scalpel". The direct visualisation of an active, controllable penetration of the abdominal wall is expected to become indispensable. A selected variety of endoscopically assisted trocar and cannula systems such as the "windowed trocar", the "optical trocar", the "Visiport" and the "optical scalpel" are described.