3D Models Related Images

View of the Jugular Foramen Region after Petrosectomy and Mastoidectomy

Surgical Correlation


View of the jugular foramen region after petrosectomy and mastoidectomy. The cranial nerve VII-VIII complex has been transected from the root exit zone to the geniculate ganglion, allowing visualization of the anterior inferior cerebellar artery. Cranial nerves IX, X and XI exit the lateral medulla and traverse the lateral medullary cistern into the jugular foramen. The jugular foramen is divided into two sections: the smaller anteromedial pars nervosa and the larger posterolateral pars vascularis. Within the pars nervosa is the inferior petrosal sinus and the glossopharyngeal nerve (IX). Within the pars vascularis courses the sigmoid sinus, the vagus and spinal accessory nerves, and the posterior meningeal branch of the ascending pharyngeal artery (not visible). Deep to the tympanic membrane, the middle ear consists of the stapes, the incus and the malleus bones. The chorda tympani courses directly over the tympanic membrane and middle ear complex. The incus is connected to the mastoid bone via the incus posterior ligament and, in combination with the ligaments of the malleus, forms the axis around which the ossicles rotate. (Image courtesy of AL Rhoton, Jr.)