Idiopathic sphenoidal defects detected by 3D computed tomography.

A 38-year-old man with pneumococcal meningitis, pneumocephalus, and CSF rhinorrhea was admitted to our hospital. The CSF rhinorrhea had no traumatic or iatrogenic etiology. The patient was treated with meropenem and recovered from meningitis. Axial plain CT showed pneumocephalus (figure 1, A and B), but no skull defects. Three-dimensional CT revealed defects of the posterior walls of the sphenoidal sinus (clivus) (figure 2A), which were not seen on plain CT (figure 1, C–F), although it was reported that clivus defects could be detected by axial plain CT.1,2 The defects were repaired with transsphenoidal surgery (figure 2B, see page 158).