[The operative cavity in the treatment of congenital atresia (author's transl)].

In the treatment of the various malformations of the external and middle ear (atresia of the bony canal, malformed ossicles, reduced volume of the middle ear in varying degrees, atypical course of the facial nerve), the indirect approach to the middle ear via the antrum appears to be the safest operative procedure for a tympanoplasty in cases of congenital atresia. A wide open external canal is required for a permanently successful hearing result. A special double plasty using skin and periosteum for the anterior canal wall has proved to be the method of choice.