Relationship of eustachian tube bony landmarks and temporal bone pneumatization.

Anatomic and functional differences of the eustachian tube have been suggested as etiologic factors in patients with otitis media. We studied eustachian tube lengths and vectors of the tensor veli palatini muscle in 25 unilateral specimens from adult human cadavers. The extent of temporal bone pneumatization, as determined by computed tomography and plain lateral radiographs, was used as an indicator of prior otitis media. Increased length of the cartilaginous eustachian tube was associated positively (r = .53, p less than .01) with volume of pneumatization. However, neither the length of the bony eustachian tube nor the vector of maximum pull of the tensor veli palatini muscle was associated statistically with the extent of pneumatization. It may be that the longer cartilaginous eustachian tube is more protective of the middle ear.