Outline of content Temporal fossa Infratemporal fossa Pterygopalatine fossa Terminal branches of external carotid artery Pterygoid venous plexus Boundary Content Communication Mandibular division of trigeminal nerve Chorda tympani and otic ganglion
Temporal fossa Depression in the lateral skull, above zygomatic arch and infratemporal crest of sphenoid bone Bounded by Processes of frontal & zygomatic bones superior temporal line Supramastoid crest Zygomatic arch
Temporal fossa Maxilla Frontal Sphenoid Parietal Temporal Floor Parietal bone Frontal bone Greater wing of sphenoid bone Squamous part of temporal bone Pterion : A thin-boned area on lateral side of head, where those 4 bones articulate Clinical landmark overlies anterior branch of middle meningeal artery, within skull
Pterion about 4 cm from zygomatic arch about 3 cm from zygomatic frontal bone landmark for frontal / anterior branch of middle meningeal artery
Pterion Trauma to the pterion can lead to tearing of the meningeal branches of the middle meningeal arteries. The middle meningeal vessels lie between the dura mater and the periosteum of the internal aspect of the skull. The build up of blood in this extradural space may lead to: brain shift away from hematoma compress against midbrain and displace downward through opening of tentorium compress vasculature of midbrain and reticular formation decrease level of consciousness untreated hemorrhage may cause death in a few hour
Contents of temporal fossa Skin & superficial fascia Auricularis muscles (anterior, superior & posterior) Auriculotemporal nerve & zygomaticotemporal nerve Superficial temporal vessels Temporal & parietal branches of facial nerve Temporal fascia (Intermediate temporal vessels) Temporal muscle Deep temporal vessels
Contents of temporal fossa superficial temporal vls auriculotemporal br of CN V3 zygomaticotemporal br of CN V2 5 branches of facial nerve
Contents of temporal fossa temporal fascia temporal muscle deep temporal vessels deep temporal branch (SVE & GSA) of CN V3
Temporal fascia
Transverse Sections of Head A B A B
Transverse & Coronal Sections of Head
Communication of Temporal Fossa Communicate with infratemporal fossa Interval between Zygomatic arch, laterally Infratemporal crest of greater wing of sphenoid bone, medially Temporal muscle pass downward to insert coronoid process of mandible
Infratemporal fossa Irregular space below temporal fossa Inferior to zygomatic arch Medial to ramus of mandible Posterior to maxilla Boundary Lateral mandible Medial sphenoid bone Roof sphenoid bone Anterior maxilla Posterior - free
Infratemporal fossa Contents Lower part of temporal muscle Medial & lateral pterygoid muscles Maxillary artery & vein Pterygoid venous plexus Mandibular division of trigeminal nerve Chorda tympani CN VII Otic ganglion CN IX
Infratemporal fossa Contents Lower part of temporal muscle Medial & lateral pterygoid muscles Maxillary artery & vein Pterygoid venous plexus Mandibular division of trigeminal nerve Chorda tympani CN VII Otic ganglion CN IX
Coronal Sections of Head
Maxillary artery Terminal branch of external carotid artery 3 parts related to lateral pterygoid muscle Mandibular part Pterygoid part Pterygopalatine part
Pterygoid venous plexus Network of vein in infratemporal fossa, surrounding maxillary artery Situate between temporal and external pterygoid muscles, partly between 2 pterygoid muscles Receives numerous veins corresponding with branches of maxillary artery
Tributaries Pterygoid Venous Plexus Cavernous sinus Maxillary vein (& superficial temporal vein) Facial vein Retromandibular vein (& facial vein) Common facial vein Internal jugular vein (& posterior auricular vein) External jugular vein Subclavian vein
Pterygoid venous plexus Continuous with Cavernous venous sinus Veins of orbit Veins of superficial face These connections have clinical importance, Veins of head, including pterygoid venous sinus, do not have valve Thus infection may spread from face to cavernous sinus
Mandibular division of Trigeminal nerve Formed by union of sensory and motor roots Motor fiber to muscles derived from first pharyngeal arch Exit cranial cavity, through foramen ovale Undivided trunk Anterior division Long buccal nerve Posterior division Lingual nerve Inferior alveolar nerve Auriculotemporal nerve
Undivided trunk of CN V3 Meningeal branch, enter foramen spinosum Nerve to medial pterygoid muscle, Nerve to tensor palatine muscle Nerve to tensor tympani muscle
Branches of anterior division of CN V3 Masseter nerve Deep temporal nerves Nerve to lateral pterygoid muscle Long buccal nerve
Branches of posterior division of CN V3 Lingual nerve supply floor of mouth, lingual gingiva, ant 2/3 tongue & chordae tympani taste (ant.2/3 of tongue) submandibular ganglion Inferior alveolar nerve mylohyoid branch inferior dental branch incisive branch mental branch Auriculotemporal nerve parotid branch articular branch anterior auricular branch superficial temporal branch
Chorda tympani (CN VII) & Otic ganglion (CN IX) Otic ganglion parasympathetic ganglion of CN IX; supply parotid gland Chorda tympani taste fiber (SVA) from ant 2/3 of tongue parasympathetic fiber (GVE) to submandibular ganglion supply sublingual & submandibular salivary glands
Communications of Infratemporal Fossa Temporal fossa Cranial fossa : foramen ovale & foramen spinosum Orbital cavity : inferior orbital fissure Pterygopalatine fossa : pterygomaxillary fissure Posterior superior alveolar canal
Pterygopalatine (or sphenopalatine) Fossa Small pyramidal space, inferior to apex of orbit Between pterygoid process of sphenoid bone and tuberosity of maxilla Medial wall - vertical plate of palatine bone Lateral - pterygomaxillary fissure Roof - greater wing of sphenoid bone Floor pyramidal process of palatine bone
Contents of Pterygopalatine Fossa Third part of maxilllary artery & its branches Maxillary division of trigeminal nerve Pterygopalatine (or sphenopalatine) ganglion
Communications of Pterygopalatine Fossa Infratemporal fossa : pterygomaxillary fissure Nasal cavity : sphenopalatine foramen Orbital cavity : inferior orbital fissure Oral cavity : palatine canal Cranial cavity : foramen rotundum Pharynx : pterygoid canal