[Endoscopic ethmoidectomy. How to prevent complications?].

The use of the microscope and more recently of the endoscope, improve the conditions of endonasal surgery. These techniques must not give the impression of complete security. The complications of the ethmoidectomy exist. A good knowledge of the anatomy of the sinus cavities and a gradual apprenticeship are the best means to prevent these complications. We present the different types of complications and their preventions.