Computed tomographic versus surgical findings in complicated acute otomastoiditis.

Computed tomography (CT) plays an important role in planning surgery in cases of complicated middle ear infection. The purpose of this study was to determine, by comparison of radiologic and surgical findings, the diagnostic value of CT in complicated acute otomastoiditis. The study group consisted of 37 patients without a history of chronic ear disease. In this study, CT enabled correct diagnosis of 26 of 27 cases (96%) of subperiosteal abscess, 17 of 18 cases (94%) of mastoid cortex erosion in patients with subperiosteal abscess, and several intracranial complications, including epidural abscess, subdural empyema, and perisinus abscess. The CT scan produced overdiagnosis in some cases: sigmoid sinus thrombosis in 1 patient, mastoid cortex erosion in 2 children with subperiosteal abscess, and bone erosion toward the posterior cranial fossa in 1 patient with meningitis. My findings suggest that subperiosteal abscess is a disease of young children; however, when it develops in an older child, cholesteatoma should be suspected. Furthermore, acute mastoiditis complicated with facial nerve paralysis may be associated with cholesteatoma in 66% of cases. My experience showed that CT had a sensitivity of 97% and a positive predictive value of 94% in the diagnosis of complicated acute otomastoiditis.