Chapter 8 Stuff to Remember Anterior View of Skull Orbit several bones joined together Frontal zygomatic sphenoid ethmoid lacrimal palatine maxillary Superior and inferior orbital fissures Opening of optic canal Lateral View of Skull Pterygopalatine Fossa underneath zygomatic arch upper part of the ramus of the mandible Surrounded by maxilla in front greater wing and pterygoid process of scaphoid bone in back body of sphenoid from above and the palatine bone medially Pyterygoid canal nerve and artery of the pterygoid canal Greater and lesser palatine canals greater and lesser palatine canals Pharyngeal canal pharyngeal branch of the maxillary nerve and the pterygoid branches of the maxillary nerve and the pterygoid branches of the maxillary artery Sphenopalatine foramen connects nasal cavity with the pterygopalatine fossa transmits the sphenopalatine artery and vein and superior nasal and nasopalatine nerves Foramen rotundum transmits maxillary nerve Infratemporal Fossa underneath upper part of ramus and mandible maxilla anterior and inferior borders parts of sphenoid posterior and superior boundaries lateral pterygoid plate medial boundary ramus of mandible surround it laterally Inferior basal View of Skull Incisive foramen nasopalatine nerve and vessels Greater and lesser palatine foramina greater and lesser palatine nerves and vessels Foramen ovale mandibular nerve Foramen rotundum maxillary nerve Foramen spinosum middle meningeal artery and a small branch of the of the trigeminal artery Foramen lacerum covered by cartilage in a living person transmits small vessels internal carotid artery runs above and across but not through Carotid canal internal carotid artery Jugular foramen internal jugular vein and cranial nerves IX X and XI Stylomastoid foramen facial nerve and stylomastoid artery Mandibular fossa site for articulation wit the mandible External acoustic meatus Foramen magnum spinal cord vertebral arteries accessory nerves spinal vessels Condylar canal transmits emissary veins Inferior View of the Skull Anterior Cranial Fossa Foramen caecum emissary vein Cribiform plates flank crista galli transmits olfactory nerves CNI Middle Cranial Fossa Optic Canal optic nerve and ophthalmic artery Superior Orbital fissure cranial nerves III IV V and VI ophthalmic veins sympathetic nerves Foramen rotumdum maxillary nerve Foramen ovale mandibular branch of trigeminal nerve Foramen spinosum middle meningeal artery Greater and lesser petrosal fissures behind foramen ovale and foramen spinosum greater and lesser petrosal nerve superior tympanic artery lesser Carotid Canal internal carotid artery sympathetic nerve plexus Posterior Cranial Fossa Internal acoustic meatus cranial nerves VII VII and labyrinthine artery Jugular foramen cranial nerves IX X XI meningeal arteries Hypoglossal canal hypoglossal nerve Foramen magnum spinal cord vertebral arteries accessory nerve Mandible Mandibular foramen inferior alveolar nerve branch of mandibular nerve CN V3 Mental foramen terminal branch of alveolar nerve leaves mental foramen as mental nerve Innervation of the Head Three branches of trigeminal nerve innervate face Ophthalmic branch skin of forehead in mediolateral direction via supratrochlear and supraorbital nerves and laterally via zygomaticotemporal nerve area above the orbitand the superolateral aspect of the nose Maxillary nerve infraorbital region Mandibular nerve mandible area below and lateral to the oral region Greater occipital nerve C2 skin scalp of posterior and lateral aspects of the head Third occipital nerve C3 lateral aspect of upper neck in retromandibular region and continues in front over the thyroid area C4 C6 nerves posterior lateral and anterior aspects of neck Facial nerve CN VII superficial muscles of face Mandibular branch of CNV deeper muscles of face masticatory muscles masseter medial lateral pterygoids and temporalis Accessory nerve sternocleidomastoid and trapezius Cervical ansa cervical plexus infrahyoid muscles in deeper layer on anterior aspect of the neck Branches of cranial nerves V VII cranial nerves suprahyoid muscles Skin Innervation and Blood Supply Skin is covered in hair sebaceous and sweat glands strongly bounded to subcutaneous tissue Scalp is made up of 5 layers skin subcutaneous tissue or superficial fascia thick strong containing vessels and nerves aponeurosis of Galea deep fascia subaponeurotic layer and the pericranium periosteum loosely fixed to the bones by connective tissue 1st 2nd and 3rd layers can move easily as a unit over one another Innervated by cervical nerves and terminal branches of trigeminal nerve Blood Supply Supraorbital and supratrochlear branches of ophthalmic artery carry blood to forehead region Superficial temporal posterior auricular and occipital branches of external carotid artery supply blood to superior lateral and posterior aspects of head Regions of the Head Frontal Region Boundaries Forehead and anterior portion of head o Superior and inferior coronal suture and supraorbital margin o Medial line near the midline of the forehead o Lateral boundary reaches anterior aspect of temporal lines Superficial sensory nerves can be seen beneath the skin terminal branches of ophthalmic nerve supraorbital and supratrochlear nerves along with arteries and veins Underneath nerves mimetric muscles including orbicularis oculi corrugator supercilli and frontal bellies of epicranius and galea aponeurosis Temporal Region From superior temporal line down to zygomatic arch Temporoparietalis a mimetic muscle superficial beneath skin Skin of region skin over ramus of the mandible parts of the auricle and the external auditory meatus innervated auriculotemporal nerve branch of mandibular branch of trigeminal Under skin mimetic muscles innervated by temporal and zygomatic branches of the facial nerve o Superficial temporal artery and superficial temporal veins can also be seen Temporalis muscle deep in region innervated by deep temporal muscles coming from CN V3 Seep anterior and posterior temporal arteries can be seen supplying deep muscles Occipital and Nuchal Regions Occipital region over occipital bone continuous with posterior cervical region nuchal nuchal region between the external occipital protuberance and the mastoid process down to spinous process of C7 vertebra Greater and lesser occipital nerves C2 and third occipital nerve C3 innervate skin Nuchal region innervated by lesser occipital nerve C2 behind ear great auricular nerve