title: Assessment of the anatomical relationship between the arcuate eminence and superior semicircular canal by computed tomography.
abstract: The anatomical relationship between the arcuate eminence (AE) and the superior semicircular canal (SSC) was examined by computed tomography (CT) in 52 petrous bones of 26 patients. After acquiring volume data by multidetector CT, 1-mm thick oblique bone window images perpendicular to the SSC were obtained from the axial images. The distances between the AE and the SSC, and the SSC and the superior surface of the petrous bone were measured. The AE corresponded exactly with the SSC in only 2/52 petrous bones, and corresponded well in 7/52. The AE was lateral to the SSC in 25/52 cases, medial to the SSC in 6/52 cases, intersected in 3/52 cases, and was indiscernible in 9/52 cases. The distance between the SSC and the petrous surface was 0 mm in 45/52 petrous bones, 1 mm in 5/52, 2 mm in 1/52, and 3 mm in 1/52. The SSC typically does not correspond exactly with the AE, and is generally located just under the surface of the petrous bone. Planning of the middle cranial fossa approach requires location of the SSC by CT.
authors.affiliation: Department of Neurosurgery, Nakamura Memorial Hospital, Chuo-ku, Sapporo, Hokkaido, Japan. yseo@med.nmh.or.jp
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Seo
authors.forename: Tamio
authors.initials: T
authors.lastname: Ito
authors.forename: Takehiko
authors.initials: T
authors.lastname: Sasaki
authors.forename: Jyoji
authors.initials: J
authors.lastname: Nakagawara
authors.forename: Hirohiko
authors.initials: H
authors.lastname: Nakamura
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000886:Anthropometry / Q000379:methods; D002648:Child; D003056:Cochlear Nerve / Q000033:anatomy & histology / Q000601:surgery; D035301:Cranial Fossa, Middle / Q000033:anatomy & histology* / Q000000981:diagnostic imaging* / Q000601:surgery; D007758:Ear, Inner / Q000033:anatomy & histology / Q000000981:diagnostic imaging / Q000601:surgery; D005154:Facial Nerve / Q000033:anatomy & histology / Q000601:surgery; D005155:Facial Nerve Diseases / Q000601:surgery; D005260:Female; D006801:Humans; D008297:Male; D008866:Microsurgery / Q000379:methods / Q000592:standards; D008875:Middle Aged; D019635:Neurosurgical Procedures / Q000379:methods / Q000592:standards; D010579:Petrous Bone / Q000033:anatomy & histology* / Q000000981:diagnostic imaging* / Q000601:surgery; D012016:Reference Values; D012665:Semicircular Canals / Q000033:anatomy & histology* / Q000000981:diagnostic imaging* / Q000601:surgery; D013701:Temporal Bone / Q000033:anatomy & histology / Q000000981:diagnostic imaging / Q000601:surgery; D014057:Tomography, X-Ray Computed / Q000379:methods; D014725:Vestibular Nerve / Q000033:anatomy & histology / Q000601:surgery; D000160:Vestibulocochlear Nerve Diseases / Q000601:surgery