55: Major Vascular Injuries in Children Undergoing Myringotomy for Tube Placement

The temporal bone is home to some of the largest vascular structures encountered in the head and neck region. Both the internal carotid artery and the internal jugular vein traverse the temporal bone emoute from the neck to the cranial vault. Knowledge of the normal anatomic position of these structures is crucial in minimizing the risk for major vascular injuries during otologic surgery. The internal carotid artery normally enters the temporal bone through the carotid canal, beginning just medial to the styloid process. It ascends vertically anterior to the tympanic cavity, then bends sharply anteriorally and medially. It passes inferior to the eustachian tube, then through the foramen lacerum to enter the cranium at the petrous apex.l The jugular bulb forms the connecting link between the internal jugular vein inferiorly and the sigmoid and inferior petrosal sinuses superiorly. It normally rests in the jugular fossa, which is a hollowed concavity in the undersurface of the petrous bone beneath the middle ear cavity. It averages 15 mm wide ~2 mm high and is larger on the right in 75% of the patients because the contributing transverse sinus tends to be larger on the right.2-” Both the internal carotid artery and the jugular bulb are normally encased in compact bone. This anatomic feature, and the surgeon’s