gms | German Medical Science

Background: Spontaneous dehiscences of the lateral skull base are a not uncommon finding in cadaver studies. Clinical signs may be a persistent middle ear effusion or conductive hearing loss. The most significant complication and sometimes initial presentation of persistent cerebrospinal fluid leakage is a bacterial meningitis.

Materials and methods: In this retrospective analysis we report on two patients with meningitis caused by pneumococci. Radiologic examination showed bilateral dehiscences in the lateral skull base in both cases. Medical treatment was performed in the years 2006 and 2007 in the Martin-Luther-University Halle/Wittenberg, Germany.

Results: The initial CT-scan showed an unilateral mastoidal opacification. Afterwards a high-resolution CT of the temporal bone approved bony dehiscences of the tegmen tympani or mastoideum in both cases on both sides. An infection per continuitatem was assumed. Within the surgical exploration through a transmastoidal approach in one case the radiological findings could be confirmed. A sufficient repair was obtained using multilayered technique. In the other case a conservative treatment at intensive care unit was successful.

Conclusion: Spontaneous dehiscences of the lateral skull base present an anatomical variation with meningitis as an uncommon initial clinical sign. A high-resolution CT-scan of the temporal bone is essential for the exact diagnosis. Normally a transmastoidal approach is adequate for successful surgery. We recommend the application of temporalis fascia, fibrin glue and bone meal in context of multilayered closure.