A reliable radiologic landmark for the facial nerve in axial temporal bone computed tomography scans.
OBJECTIVE
We sought to test the reliability of a radiologic marker in identifying the vertical portion of the facial nerve in axial computed tomography (CT) temporal bone scans.


METHODS
At a tertiary care academic center, we used, with a random sample of 25 CT scans, a marker (the "B-line") to identify the facial nerve. The variations in distance from this marker to the facial nerve were measured.


RESULTS
This marker, which consists of a tangent line extrapolated from the posterior border of the basal turn of the cochlea, fell within 1 mm of the facial nerve on average. The average distance from the midpoint of the posterior border of the basal turn of the cochlea to the facial nerve was 11 +/- 1 mm.


CONCLUSIONS
This is a very reliable marker for the vertical portion of the facial nerve.


CONCLUSIONS
This marker can be used to rapidly find the facial nerve, even in diseased or postsurgical temporal bones.
Bance
Manohar
M
Department of Otology/Neurotology, Division of Otolaryngology, Dalhousie University. m.bance@dal.ca
Erb
Jason
J
D005154:Facial Nerve / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008297:Male; D010036:Otolaryngology / Q000379:methods; D015203:Reproducibility of Results; D013701:Temporal Bone / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed