Abnormal petrous apex aeration. Review of 12 cases.

OBJECTIVE

Abnormal aeration of the petrous bone, which may be responsible for some clinical symptoms, is an incidental radiological finding. It has been reported that people with abnormal aeration at the petrous bone are more prone to develop complications. In an attempt to make clear the clinical importance of a giant air cell at the petrous apex or abnormal aeration of this region, a prospective analysis has been planned.

METHOD: 430 temporal bone CTs taken for diagnostic imaging only between 1992-2000 have been reviewed and 12 cases with petrous air cell were selected. Aeration was measured on computer basis. Patients were invited for interview and subjected to complete audilogical and ENG testing Symptoms of the patients were reviewed and the possible link with the radiological findings has been discussed.

RESULTS

The internal distance of the air cell was ranging between 1.6 to 2.5 cm at transverse axis and between 2.0 to 4.2 cm at longitudinal axis. It was noted that all patients with large air cell at the apex also had extensive mastoid and temporal bone aeration. The degree of temporal bone aeration and the size of air cell was the same in both sexes. Four patients had balance problems. One patient had sudden hearing loss. Two patients had Bell's palsy. Two patients were asymptomatic. Six patients had normal hearing level. Five patients demonstrated ENG abnormality.

CONCLUSIONS

It was found that these patients had some ear symptoms which were usually vague and nonlocalizing. It was unlikely to attribute these symptoms to a giant apical air cell or abnormal aeration of the petrous bone.