Surgical anatomy of petrous part of the internal carotid artery

The purpose of this study was to reveal the anatomical relationships of petrous part of the internal carotidartery. Sixteen human cadavers were investigated via preauricular surgical approach (bilateral exposure oneach cadaver). A 6 cm long incision was made in front of the auricle, along the posterior border of the ramusof mandible, as higher as the level of the temporomandibular joint. After luxation of temporo-mandibulararticulation and milling of tympanic bone, vertical and horizontal segments of petrous part of the internalcarotid artery were exposed.The vertical segment’s mean length was 12 mm (ranged 10 mm to 15 mm). The relationships of the verticalsegment were the jugular fossa posteriorly, tympanic bone laterally, and Eustachian tube anteriorly. Horizontalsegment’s mean length was 20 mm (ranged 18 mm to 22 mm). Angle between vertical and horizontal segmentsof the petrous part of the internal carotid artery was measured 105° (ranged 95 to 110°).V, VII, IX, X, XII cranial nerves, internal jugular vein, and Eustachian tube are important structures, whichmust be protected during high carotid surgery.