[Meningocerebral hernia and defects of the tegmen. Diagnosis and surgical treatment].

Eight defects of the tegmen tympani or antri have been operated on during the last two years. Among these cases, 4 brain herniae were associated with the defect of the tegmen. Magnetic resonance imaging permitted to evaluate accurately the space occupying lesions into the mastoid cavity and disclosed the brain and/or meningeal herniations. The defect of the tegmen was oblitered through a middle fossa approach whereas the hernia was resected through a mastoid approach when necessary.