Persistent stapedial artery: CT findings.

CT of a patient with conductive hearing loss showed a small vascular structure leaving the carotid canal and passing through the stapes to join the facial nerve canal. The small bony channel paralleled the anterior tympanic segment of the facial nerve, continuing beyond the geniculate ganglion into the middle cranial fossa. Otoendoscopic photography documented the presence of a persistent stapedial artery.