Relationship of petrous temporal bone pneumatization to the eustachian tube lumen.

Overview

OBJECTIVES/HYPOTHESIS: Objectives were to determine the incidence of petrous apex pneumatization and to define the relationship between a pneumatized petrous temporal bone and the eustachian tube lumen. STUDY DESIGN: Retrospective study with institutional review board approval including only adult patients. METHODS: One hundred head computed tomography (ct) scans and 204 petrous temporal bone CT scans performed at a tertiary teaching hospital were reviewed. The two senior authors (s.h.s., p.c.s.) independently reviewed the petrous temporal bone CT scans for grade of pneumatization. Pneumatized CT scans were then reviewed for the presence of a direct communication with the eustachian tube lumen. Significance was determined using the chi test and Pearson correlation of ranks. RESULTS: The incidence of peritubal cells opening into the eustachian tube anterior to the tympanic orifice was 92%. CONCLUSION: The direct communication of peritubal cells with the bony eustachian tube may play a role in the development of persistent cerebrospinal fluid rhinorrhea after cerebellopontine angle surgery.