1. Facial nerve and pterygopalatine fossa
Dissection reveals the facial nerve branches, hypoglossal nerve, stylohyoid muscle, accessory nerve, vagus nerve, and inferior facial vein. The posterior neck dissection exposes the great auricular nerve, splenius, and trapezius muscles. Further dissection of the skull base reveals the trigeminal nerve divisions, middle meningeal artery, optic nerve, and internal carotid artery. The medial surface dissection exposes the turbinates and pterygopalatine structures, and the sphenoid sinus is opened to reveal the sellar floor.
Annotations Facial nerve (VII), Frontal branch of the facial nerve, Zygomatic branch of the facial nerve, Buccal branch of the facial nerve, Mandibular branch of the facial nerve, Ramus colli of the facial nerve, Masseter muscle, Hypoglossal nerve (XII), Stylohyoid muscle, Sternocleidomastoid muscle, Digastric muscle, Vagus nerve (X), Inferior facial vein, Great auricular nerve, Splenius muscle, Trapezius muscle, Tentorium, Orbital roof, Greater sphenoid wing, Cribriform plate, Superior petrosal sinus, Arcuate eminence, Middle meningeal artery, Mandibular division of trigeminal nerve (V3), Maxillary division of the trigeminal nerve (V2), Gasserian ganglion, Ophthalmic division of trigeminal nerve (V1), Superior orbital fissure, Oculomotor nerve (III), Anterior clinoid process, Internal carotid artery, Middle cerebral artery, Anterior cerebral artery, Optic nerve (II), Tuberculum sellae, Inferior turbinate, Medial turbinate, Superior turbinate, Pterygopalatine nerve, Pterygopalatine artery.
Dissection reveals the facial nerve branches, hypoglossal nerve, stylohyoid muscle, accessory nerve, vagus nerve, and inferior facial vein. The posterior neck dissection exposes the great auricular nerve, splenius, and trapezius muscles. Further dissection of the skull base reveals the trigeminal nerve divisions, middle meningeal artery, optic nerve, and internal carotid artery. The medial surface dissection exposes the turbinates and pterygopalatine structures, and the sphenoid sinus is opened to reveal the sellar floor.
Annotations Facial nerve (VII), Frontal branch of the facial nerve, Zygomatic branch of the facial nerve, Buccal branch of the facial nerve, Mandibular branch of the facial nerve, Ramus colli of the facial nerve, Masseter muscle, Hypoglossal nerve (XII), Stylohyoid muscle, Sternocleidomastoid muscle, Digastric muscle, Vagus nerve (X), Inferior facial vein, Great auricular nerve, Splenius muscle, Trapezius muscle, Tentorium, Orbital roof, Greater sphenoid wing, Cribriform plate, Superior petrosal sinus, Arcuate eminence, Middle meningeal artery, Mandibular division of trigeminal nerve (V3), Maxillary division of the trigeminal nerve (V2), Gasserian ganglion, Ophthalmic division of trigeminal nerve (V1), Superior orbital fissure, Oculomotor nerve (III), Anterior clinoid process, Internal carotid artery, Middle cerebral artery, Anterior cerebral artery, Optic nerve (II), Tuberculum sellae, Inferior turbinate, Medial turbinate, Superior turbinate, Pterygopalatine nerve, Pterygopalatine artery.
2. Uncinate process and bulla ethmoidalis, vagus nerve and ansa cervicalis
The exocranial neck dissection includes lateral mobilization of the sternocleidomastoid muscle to visualize the common carotid artery (CCA) and its bifurcation, and removal of the submandibular fat pad to expose the facial artery and styloglossus muscle. The hypoglossal nerve (XII) is dorsal to the CCA bifurcation. Posterior cranial fossa dissection involves resecting the tentorium, revealing the straight sinus, superior cerebellar surface, and transversus sinus. Tentorial dura resection exposes the trochlear nerve (IV), trigeminal nerve (V), and the facial and vestibulocochlear nerves complex (VII and VIII). Endocranial dissection of the middle turbinate exposes the uncinate process, bulla ethmoidalis, semilunar hiatus and maxillary sinus opening.
Annotations Facial nerve (VII), Frontal branch of the facial nerve, Zygomatic branch of the facial nerve, Buccal branch of the facial nerve, Mandibular branch of the facial nerve, Ramus colli of the facial nerve, Masseter muscle, Hypoglossal nerve (XII), Styloglossus muscle, Sternocleidomastoid muscle, Digastric muscle, Vagus nerve (X), Facial artery, Internal jugular vein, Common carotid artery, Internal carotid artery, External carotid artery, Superior root of ansa cervicalis, Accessory nerve (XI), Semispinalis capitii muscle, Splenius muscle, Occipitalis major nerve (greater auricular nerve), Superior (tentorial) cerebellar surface, Straight sinus, Transverse sinus, Tegmen tympani, Throclear nerve, Trigeminal nerve, Vestibulocochlear nerve, Suprameatal tubercle, Arcuate eminence, Middle meningeal artery, Mandibular branch of trigeminal nerve (V3), Maxillary branch of trigeminal nerve (V2), Ophtalmic branch of the trigeminal nerve (V1), Oculomotor nerve (III), Internal carotid artery, Middle cerebral artery, Anterior cerebral artery, Optic nerve (II), Superior turbinate, Inferior turbinate, Uncinate process, Bulla ethmoidalis, Pterygopalatine artery, Pterygopalatine nerve, Eustachian tube, Pituitary gland, carotid prominence.
The exocranial neck dissection includes lateral mobilization of the sternocleidomastoid muscle to visualize the common carotid artery (CCA) and its bifurcation, and removal of the submandibular fat pad to expose the facial artery and styloglossus muscle. The hypoglossal nerve (XII) is dorsal to the CCA bifurcation. Posterior cranial fossa dissection involves resecting the tentorium, revealing the straight sinus, superior cerebellar surface, and transversus sinus. Tentorial dura resection exposes the trochlear nerve (IV), trigeminal nerve (V), and the facial and vestibulocochlear nerves complex (VII and VIII). Endocranial dissection of the middle turbinate exposes the uncinate process, bulla ethmoidalis, semilunar hiatus and maxillary sinus opening.
Annotations Facial nerve (VII), Frontal branch of the facial nerve, Zygomatic branch of the facial nerve, Buccal branch of the facial nerve, Mandibular branch of the facial nerve, Ramus colli of the facial nerve, Masseter muscle, Hypoglossal nerve (XII), Styloglossus muscle, Sternocleidomastoid muscle, Digastric muscle, Vagus nerve (X), Facial artery, Internal jugular vein, Common carotid artery, Internal carotid artery, External carotid artery, Superior root of ansa cervicalis, Accessory nerve (XI), Semispinalis capitii muscle, Splenius muscle, Occipitalis major nerve (greater auricular nerve), Superior (tentorial) cerebellar surface, Straight sinus, Transverse sinus, Tegmen tympani, Throclear nerve, Trigeminal nerve, Vestibulocochlear nerve, Suprameatal tubercle, Arcuate eminence, Middle meningeal artery, Mandibular branch of trigeminal nerve (V3), Maxillary branch of trigeminal nerve (V2), Ophtalmic branch of the trigeminal nerve (V1), Oculomotor nerve (III), Internal carotid artery, Middle cerebral artery, Anterior cerebral artery, Optic nerve (II), Superior turbinate, Inferior turbinate, Uncinate process, Bulla ethmoidalis, Pterygopalatine artery, Pterygopalatine nerve, Eustachian tube, Pituitary gland, carotid prominence.
3. Lamina papyracea
The exocranial dissection of the lateral head exposes the masseteric nerve and the trajectory of the hypoglossal nerve (XII), along with the superior thyroid artery branching from the external carotid artery. Removal of the splenius muscle reveals the longissimus capitis and deeper posterior neck muscles and the suboccipital triangle muscles. Presigmoid retrolabyrinthine drilling of the mastoid exposes the sigmoid sinus and facial nerve. Further dissection of the cerebellum and periorbital fat reveals intraorbital nerves. Endocranial drilling of the sphenoid sinus exposes segments of the internal carotid artery and optic-carotid recess, along with the lamina papyracea.
Annotations Zygomatic branch of the facial nerve, Buccal branch of the facial nerve, Mandibular branch of the facial nerve, Ramus colli of the facial nerve, Facial artery, Facial vein, Facial nerve (VII), Digastric muscle, Common carotid artery, Internal carotid artery, External carotid artery, Hypoglossal nerve (XII), Internal jugular vein, Sternocleidomastoid muscle, Accessory nerve (XI), Vagus nerve (X), Longissimus capitis muscle, Levator scapulae muscle, Semispinalis capitis muscle, Splenium muscle, Spinous process of C2, Rectus capitis posterior major muscle, Rectus capitis posterior minor, Superior oblique muscle, Inferior oblique muscle, Sigmoid sinus, Intrafallopian course of the facial nerve, Labyrinthine block, Digastric sulcus, Straight sinus, Transverse sinus, Tentorial incisura, Gasserian ganglion, Mandibular branch of the trigeminal nerve, Maxillary branch of the trigeminal nerve, Ophthalmic branch of the trigeminal nerve, Throclear nerve (IV), Oculomotor nerve (III), Frontal nerve, Sellar floor, Sphenoid sinus, Lacerum segment (C3) of the internal carotid artery, C5 segment of the internal carotid artery, Optico-carotid recess, Eustachian tube, Pterygopalatine ganglion, Inferior turbinate, Pterygopalatine artery, Pterygopalatine, nerve, Lamina papyracea.
The exocranial dissection of the lateral head exposes the masseteric nerve and the trajectory of the hypoglossal nerve (XII), along with the superior thyroid artery branching from the external carotid artery. Removal of the splenius muscle reveals the longissimus capitis and deeper posterior neck muscles and the suboccipital triangle muscles. Presigmoid retrolabyrinthine drilling of the mastoid exposes the sigmoid sinus and facial nerve. Further dissection of the cerebellum and periorbital fat reveals intraorbital nerves. Endocranial drilling of the sphenoid sinus exposes segments of the internal carotid artery and optic-carotid recess, along with the lamina papyracea.
Annotations Zygomatic branch of the facial nerve, Buccal branch of the facial nerve, Mandibular branch of the facial nerve, Ramus colli of the facial nerve, Facial artery, Facial vein, Facial nerve (VII), Digastric muscle, Common carotid artery, Internal carotid artery, External carotid artery, Hypoglossal nerve (XII), Internal jugular vein, Sternocleidomastoid muscle, Accessory nerve (XI), Vagus nerve (X), Longissimus capitis muscle, Levator scapulae muscle, Semispinalis capitis muscle, Splenium muscle, Spinous process of C2, Rectus capitis posterior major muscle, Rectus capitis posterior minor, Superior oblique muscle, Inferior oblique muscle, Sigmoid sinus, Intrafallopian course of the facial nerve, Labyrinthine block, Digastric sulcus, Straight sinus, Transverse sinus, Tentorial incisura, Gasserian ganglion, Mandibular branch of the trigeminal nerve, Maxillary branch of the trigeminal nerve, Ophthalmic branch of the trigeminal nerve, Throclear nerve (IV), Oculomotor nerve (III), Frontal nerve, Sellar floor, Sphenoid sinus, Lacerum segment (C3) of the internal carotid artery, C5 segment of the internal carotid artery, Optico-carotid recess, Eustachian tube, Pterygopalatine ganglion, Inferior turbinate, Pterygopalatine artery, Pterygopalatine, nerve, Lamina papyracea.
4. Infratemporal fossa and orbit
The exocranial dissection extends to expose the masseteric nerve, medial pterygoid, and buccinator muscles in the infratemporal fossa, revealing the internal maxillary artery (IMAX) and the mandible. The buccal nerve is identified between the medial pterygoid and buccinator muscles. Dissecting anterior to the external auditory canal reveals the superficial temporal artery and styloid process. The suboccipital triangle and posterior atlantooccipital membrane dissection exposes the vertebral artery's V3 segment. Drilling the mastoid process reveals the facial nerve's course and exit from the sylomastoid foramen as well as the jugular bulb. Removal of the superior cerebellar surface identifies the trigeminal nerve at the cerebellopontine angle entering the porus trigeminus. Anterior cranial fossa dissection exposes intraorbital nerves and muscles. Endocranial drilling of the lamina papyracea exposes periorbital fat and the medial and inferior rectus muscles.
Annotations Masseteric nerve, Internal maxillary artery (IMAX), Medial pterygoid muscle, Buccinator muscle, Buccal nerve, External ear canal, Styloid process, Superficial temporal artery, Facial nerve (VII), Buccal branch of the facial nerve, Mandibular branch of the facial nerve, Hypoglossal nerve (XII), Internal carotid artery, External carotid artery, Superior thyroid artery, Common carotid artery, Vagus nerve (X), Superior root of ansa cervicalis, Internal jugular vein, Accessory nerve (XI), Levator scapulae muscle, Vertebral artery, C2 nerve root, C1 transverse process, Jugular bulb, Sigmoid sinus, Labyrinthine block, Intrafallopian course of the facial nerve, Cisternal segment of the trochlear nerve, Trigeminal nerve (V), Porus trigeminus, Gasserian ganglion, Mandibular branch of the trigeminal nerve, Maxillary branch of the trigeminal nerve, Ophthalmic branch of the trigeminal nerve, Oculomotor nerve (III), Frontal nerve , Optic nerve, Eustachian tube, Pterygopalatine ganglion, Optic carotid recess, Pituitary gland, Medial rectus muscle, Inferior rectus muscle.
The exocranial dissection extends to expose the masseteric nerve, medial pterygoid, and buccinator muscles in the infratemporal fossa, revealing the internal maxillary artery (IMAX) and the mandible. The buccal nerve is identified between the medial pterygoid and buccinator muscles. Dissecting anterior to the external auditory canal reveals the superficial temporal artery and styloid process. The suboccipital triangle and posterior atlantooccipital membrane dissection exposes the vertebral artery's V3 segment. Drilling the mastoid process reveals the facial nerve's course and exit from the sylomastoid foramen as well as the jugular bulb. Removal of the superior cerebellar surface identifies the trigeminal nerve at the cerebellopontine angle entering the porus trigeminus. Anterior cranial fossa dissection exposes intraorbital nerves and muscles. Endocranial drilling of the lamina papyracea exposes periorbital fat and the medial and inferior rectus muscles.
Annotations Masseteric nerve, Internal maxillary artery (IMAX), Medial pterygoid muscle, Buccinator muscle, Buccal nerve, External ear canal, Styloid process, Superficial temporal artery, Facial nerve (VII), Buccal branch of the facial nerve, Mandibular branch of the facial nerve, Hypoglossal nerve (XII), Internal carotid artery, External carotid artery, Superior thyroid artery, Common carotid artery, Vagus nerve (X), Superior root of ansa cervicalis, Internal jugular vein, Accessory nerve (XI), Levator scapulae muscle, Vertebral artery, C2 nerve root, C1 transverse process, Jugular bulb, Sigmoid sinus, Labyrinthine block, Intrafallopian course of the facial nerve, Cisternal segment of the trochlear nerve, Trigeminal nerve (V), Porus trigeminus, Gasserian ganglion, Mandibular branch of the trigeminal nerve, Maxillary branch of the trigeminal nerve, Ophthalmic branch of the trigeminal nerve, Oculomotor nerve (III), Frontal nerve , Optic nerve, Eustachian tube, Pterygopalatine ganglion, Optic carotid recess, Pituitary gland, Medial rectus muscle, Inferior rectus muscle.
5. Infra temporal fossa extended
The exocranial dissection begins with a complete osteotomy of the mandible, removing the temporomandibular joint. The external carotid artery branches into the superficial temporal artery and the IMAX. Dissection of the infratemporal fossa reveals the sphenopalatine artery and infraorbital nerve, while the mandibular division of the trigeminal nerve (CN V) branches into the lingual, buccal, and inferior alveolar nerves. The brain is removed leaving only the cranial nerve stumps. Posteriorly, retrosigmoid drilling reveals the transverse and sigmoid sinuses and cranial nerves entering in their foramina. Anteriorly, opening the cavernous sinus exposes the trochlear nerve (CN IV) and the ICA. Endocranially, drilling exposes the sphenopalatine artery and the the ICA segments from sphenoidal sinus perspective, as well as the cavernous sinus.
Annotations Superficial temporal artery, Masseteric nerve, Internal maxillary artery (IMAX), Pterygopalatine artery, Infraorbital nerve, Mandibular branch of the trigeminal nerve, Inferior alveolar nerve, Lingual nerve, Buccal nerve, Lateral pterygoid muscle, Buccinator muscle, Hypoglossal nerve, External carotid artery, Internal carotid artery, Accessory nerve (XI), Common carotid artery, Vagus nerve (X), Internal jugular artery, Facial nerve (VII), Styloid process, C2 nerve root, Vertebral artery, Occipital condyle, Sigmoid sinus, Transverse sinus, Mastoid emissary vein, Intrafallopian course of the facial nerve, Labyrinthine block, Jugular bulb, Tegmen tympani, Gasserian ganglion, Maxillary branch of the trigeminal nerve, Ophthalmic branch of the trigeminal nerve, Medial rectus muscle, Inferior rectus muscle, Inferior turbinate, Sphenopalatine artery, Pterygopalatine ganglion, Lacerum segment (C3) of the internal carotid artery, cavernous segment (C4) of the internal carotid artery, Clinoid segment (C5) of the internal carotid artery, Abducens nerve (VI).
The exocranial dissection begins with a complete osteotomy of the mandible, removing the temporomandibular joint. The external carotid artery branches into the superficial temporal artery and the IMAX. Dissection of the infratemporal fossa reveals the sphenopalatine artery and infraorbital nerve, while the mandibular division of the trigeminal nerve (CN V) branches into the lingual, buccal, and inferior alveolar nerves. The brain is removed leaving only the cranial nerve stumps. Posteriorly, retrosigmoid drilling reveals the transverse and sigmoid sinuses and cranial nerves entering in their foramina. Anteriorly, opening the cavernous sinus exposes the trochlear nerve (CN IV) and the ICA. Endocranially, drilling exposes the sphenopalatine artery and the the ICA segments from sphenoidal sinus perspective, as well as the cavernous sinus.
Annotations Superficial temporal artery, Masseteric nerve, Internal maxillary artery (IMAX), Pterygopalatine artery, Infraorbital nerve, Mandibular branch of the trigeminal nerve, Inferior alveolar nerve, Lingual nerve, Buccal nerve, Lateral pterygoid muscle, Buccinator muscle, Hypoglossal nerve, External carotid artery, Internal carotid artery, Accessory nerve (XI), Common carotid artery, Vagus nerve (X), Internal jugular artery, Facial nerve (VII), Styloid process, C2 nerve root, Vertebral artery, Occipital condyle, Sigmoid sinus, Transverse sinus, Mastoid emissary vein, Intrafallopian course of the facial nerve, Labyrinthine block, Jugular bulb, Tegmen tympani, Gasserian ganglion, Maxillary branch of the trigeminal nerve, Ophthalmic branch of the trigeminal nerve, Medial rectus muscle, Inferior rectus muscle, Inferior turbinate, Sphenopalatine artery, Pterygopalatine ganglion, Lacerum segment (C3) of the internal carotid artery, cavernous segment (C4) of the internal carotid artery, Clinoid segment (C5) of the internal carotid artery, Abducens nerve (VI).
6. Semicircular canals
On the exocranial side, drilling MacEwen's triangle and the spine of Henle, along with the tegmen tympani and arcuate eminence, exposes the semicircular canals and incus within the middle ear. An anterior petrosectomy, including drilling Kawase's and Glasscock's triangles, exposes the petrous segment (C2) of the internal carotid artery, GSPN, and Eustachian tube and the cochlea at the cochlear angle. Endocranially, the facial nerve (VII) and vestibulocochlear nerve (VIII), along with the labyrinthine artery from AICA, enter the internal acoustic meatus. Exocranially the IX nerve as well as the ascending pharyngeal artery are presented.
Annotations Sphenopalatine artery, Infraorbital nerve, Pterygopalatine artery, Mandibular branch of the trigeminal nerve, Lingual nerve, Lingual artery, Styloid process, Facial nerve (VII), Jugular vein, Hypoglossal nerve (XII), External carotid artery, Internal carotid artery, Sympathetic chain, Accessory nerve (XI), Common carotid artery, Vagus nerve (X), Transverse sinus, Sigmoid sinus, Jugular bulb, Mastoid emissary vein, Tegmen tympani, Intrafallopian course of the facial nerve, External acoustic canal, Posterior semicircular canal, Lateral semicircular canal, Superior semicircular canal, Incus, Great superficial petrosal nerve (GSPN), Petrous segment (C3) of the internal carotid artery, Middle meningeal artery, Eustachian tube, Cochlea, Maxillary branch of the trigeminal nerve, Ophthalmic branch of the trigeminal nerve, Communicating segment (C7) of the internal carotid artery, Oculomotor nerve (III), Trochlear nerve (IV), Abducens nerve (VI), Optic-carotid recess. Glossopharyngeal n., Ascending pharyngeal artery
On the exocranial side, drilling MacEwen's triangle and the spine of Henle, along with the tegmen tympani and arcuate eminence, exposes the semicircular canals and incus within the middle ear. An anterior petrosectomy, including drilling Kawase's and Glasscock's triangles, exposes the petrous segment (C2) of the internal carotid artery, GSPN, and Eustachian tube and the cochlea at the cochlear angle. Endocranially, the facial nerve (VII) and vestibulocochlear nerve (VIII), along with the labyrinthine artery from AICA, enter the internal acoustic meatus. Exocranially the IX nerve as well as the ascending pharyngeal artery are presented.
Annotations Sphenopalatine artery, Infraorbital nerve, Pterygopalatine artery, Mandibular branch of the trigeminal nerve, Lingual nerve, Lingual artery, Styloid process, Facial nerve (VII), Jugular vein, Hypoglossal nerve (XII), External carotid artery, Internal carotid artery, Sympathetic chain, Accessory nerve (XI), Common carotid artery, Vagus nerve (X), Transverse sinus, Sigmoid sinus, Jugular bulb, Mastoid emissary vein, Tegmen tympani, Intrafallopian course of the facial nerve, External acoustic canal, Posterior semicircular canal, Lateral semicircular canal, Superior semicircular canal, Incus, Great superficial petrosal nerve (GSPN), Petrous segment (C3) of the internal carotid artery, Middle meningeal artery, Eustachian tube, Cochlea, Maxillary branch of the trigeminal nerve, Ophthalmic branch of the trigeminal nerve, Communicating segment (C7) of the internal carotid artery, Oculomotor nerve (III), Trochlear nerve (IV), Abducens nerve (VI), Optic-carotid recess. Glossopharyngeal n., Ascending pharyngeal artery
7. Vertebral artery and carotid artery segments
The exocranial dissection proceeds into the infratemporal fossa after removing the mandible, exposing the middle meningeal artery branching from the IMAX and entering the skull base through the foramen spinosum. Dissection follows the cervical segment (C1) of the ICA, drilling the carotid canal to expose the petrous segment (C2). The trigeminal nerve is retracted medially and the lacerum segment (C3) , and cavernous (C4) of the ICA medially to the abducens nerve (VI). Anteriorly, dissection of the prevertebral fascia exposes cervical nerve roots, the sympathetic chain, and the superior laryngeal nerve. The foraminal segment (V2) of the vertebral artery is then exposed coursing anteriorly to the spinal nerve roots.
Annotations Sphenopalatine artery, Internal maxillary artery (IMAX), Maxillary nerve, Middle meningeal artery, Ascending pharyngeal artery, Lingual nerve, Buccal nerve, Glossopharingeal nerve (IX), Hypoglossal nerve (XII), Common carotid artery, Internal carotid artery, External carotid artery, Vagus nerve (X), External jugular vein, Facial nerve (VII), Accessory nerve (XI), Jugular bulb, Intrafallopian course of the facial nerve, Posterior semicircular canal, Lateral semicircular canal, Superior semicircular canal, Incus, Cochlea, Infraorbital nerve, Pterygopalatine artery, Pterygopalatine nerve, Optic nerve (II), Ophthalmic division of the trigeminal nerve, Maxillary division of the trigeminal nerve, Mandibular division of the trigeminal nerve, Abducens nerve (VI), Cervical segment (C1) of the internal carotid artery, Petrous segment (C2) of the internal carotid artery, Lacerum segment (C3) of the internal carotid artery, Sympathetic chain, Superior laryngeal nerve, C4 nerve root, Vertebral artery.
The exocranial dissection proceeds into the infratemporal fossa after removing the mandible, exposing the middle meningeal artery branching from the IMAX and entering the skull base through the foramen spinosum. Dissection follows the cervical segment (C1) of the ICA, drilling the carotid canal to expose the petrous segment (C2). The trigeminal nerve is retracted medially and the lacerum segment (C3) , and cavernous (C4) of the ICA medially to the abducens nerve (VI). Anteriorly, dissection of the prevertebral fascia exposes cervical nerve roots, the sympathetic chain, and the superior laryngeal nerve. The foraminal segment (V2) of the vertebral artery is then exposed coursing anteriorly to the spinal nerve roots.
Annotations Sphenopalatine artery, Internal maxillary artery (IMAX), Maxillary nerve, Middle meningeal artery, Ascending pharyngeal artery, Lingual nerve, Buccal nerve, Glossopharingeal nerve (IX), Hypoglossal nerve (XII), Common carotid artery, Internal carotid artery, External carotid artery, Vagus nerve (X), External jugular vein, Facial nerve (VII), Accessory nerve (XI), Jugular bulb, Intrafallopian course of the facial nerve, Posterior semicircular canal, Lateral semicircular canal, Superior semicircular canal, Incus, Cochlea, Infraorbital nerve, Pterygopalatine artery, Pterygopalatine nerve, Optic nerve (II), Ophthalmic division of the trigeminal nerve, Maxillary division of the trigeminal nerve, Mandibular division of the trigeminal nerve, Abducens nerve (VI), Cervical segment (C1) of the internal carotid artery, Petrous segment (C2) of the internal carotid artery, Lacerum segment (C3) of the internal carotid artery, Sympathetic chain, Superior laryngeal nerve, C4 nerve root, Vertebral artery.