[Frontobasal injuries and csf fistulas. Attempt at an anatomoclinical classification. Therapeutic incidence].

The authors present a classification of trauma to the cranial base, based on observation in 80 cases. There are five types. Type I : involves only the anterior wall of the frontal sinus. Type II : involves the face (craniofacial disjunction of the Lefort II type or crush face) and extend upward to the cranial base and, in occurency, to the anterior wall of the frontal sinus, because of the facial retrusion. Type III : ivolves frontal part of the skull and extend down to the cranial base. Type IV : is a combination of types II and III. Type V : involves only ethmoidal or sphenoidal bones. Cerebrospinal fluid leak is unfrequent in types II, and transitionnal, if it occurs ; but it often occurs in types III, IV and V which include in every case a dural tear. Correct diagnosis facilitates treatment. Fractures of types I and II can be fully treated by maxillo-facial surgeons, whereas for types III, IV, and V, they need the help of a neuro-surgeon.