Head Anatomy Flashcards
How are the bones of the skull formed?
Intramembranous ossification
What joints join the bones of the skull?
Sutures (fibrous joints)
What are the two parts of the cranium?
Neurocranium
Viscerocranium
What is the subdivisions of the cranium?
Cranial roof
Cranial base
What comprises the cranial roof?
Frontal bone
Occipital bone
2 Parietal bones
What comprises the cranial base?
Frontal bone
Sphenoid bone
Ethmoid bone
Occipital bone
Parietal bone
Temporal bone
What are the facial bones?
Zygomatic (2)
Lacrimal (2)
Nasal (2)
Inferior nasal conchae (2)
Palatine (2)
Maxilla (2)
Vomer
Mandible
What do sutures represent clinically?
Points of potential weakness in the skull
What are the main sutures in the adult skull?
Coronal suture- frontal and 2 parietal
Sagittal suture- both parietal
Lamboid suture- occipital and 2 parietal
What forms the temporomandibular joint?
Articulation of the mandible and the temporal bone of the cranium
What does the sphenoid bone consist of?
Body
Paired greater wings
Paired lesser wings
Two pterygoid processes
What two processes project out of the temporal bone?
Zygomatic process
Styloid process
What forms the zygomatic arch?
Zygomatic process of temporal bone
Temporal process of zygomatic bone
What is a foramen?
An opening that allows passage of structures from one region to another
What are the 8 cranial foramen?
Cribriform foramina
Optic canal and foramen
Superior orbital fissure
Foramen rotundum
Foramen ovale
Internal acoustic meatus
Jugular foramen
Hypoglossal canal
In which bone is the cribriform foramina?
Ethmoid bone
What does the cribriform plate foramina conduct?
Olfactory I
In which bone is the optic canal?
Sphenoid bone
What does the optical canal conduct?
Optic II
In which bone is the superior orbital fissure?
Sphenoid bone
What does the superior orbital fissure conduct?
Oculomotor III
Trochlear IV
Opthalmic V1
Abducens VI
In which bone is the foramen rotundum?
Sphenoid bone
What does the foramen rotundum conduct?
Maxillary V2
In which bone is the foramen ovale?
Sphenoid bone
What does the foramen ovale conduct?
Mandibular V3
In which bone is the internal acoustic meatus?
Temporal bone
What does the internal acoustic meatus conduct?
Facial VII
Vestibulocochlear VIII
In which bone is the jugular foramen?
Anterior: temporal bone
Posterior: occipital bone
What does the jugular foramen conduct?
Glossopharyngeal IX
Vagus X
Accessory XI
In which bone is the hypoglossal canal?
Occipital bone
What does the hypoglossal canal conduct?
Hypoglossal XII
Where are the muscles of facial expression located?
Subcutaneous tissue
What is the embryonic origin of the muscles of facial expression?
2nd pharyngeal branch
What nerve innervates all of the muscles of facial expression?
Facial nerve:
- Temporal branches
- Zygomatic branches
- Buccal branches
- marginal mandibular branches
- Cervical branches
What are the three groups of the facial muscles?
Orbital
Nasal
Oral
What muscles are part of the orbital group?
Orbicularis oculi
Corrugator supercilii
What are the three parts of the orbicularis oculi?
Palpebral
Lacrimal
Orbital
What is the action of the palpebral part of the orbicularis oculi?
Gently closes the eyelids
What is the action of the lacrimal part of the orbicularis oculi?
Drainage of tears
What is the action of the orbital part of the orbicularis oculi?
Tightly closes the eyelids
What muscles are part of the nasal group?
Nasalis
Procerus
Depressor septi Nasi
What muscles are part of the oral group?
Orbicularis oris
Buccinator
Other oral muscles
What is the action of the orbicularis oris?
Purses the lips
What is the action of the buccinator?
Pulls cheek inwards against the teeth, preventing accumulation of food in that area
What is the action of the muscles of mastication?
Movements of temporomandibular joint (jaw)
What are the muscles of mastication?
Masseter
Temporalis
Medial pterygoid
Lateral pterygoid
What is the action of the masseter muscle?
Elevates mandible, closing the mouth
What is the action of the temporalis muscle?
Elevates mandible, closing the mouth
Retracts mandible, pulling jaw posteriorly
What is the action of the medial pterygoid muscle?
Elevates the mandible, closing the mouth
What is the action of the lateral pterygoid muscle?
Bilateral: protract the mandible, pushing the jaw forward
Unilateral: side to side movement of jaw
What is the embryological origin of the muscles of mastication?
First pharyngeal arch
What nerve innervates the muscles of mastication?
Mandibular nerve (CNV3)
What are the intrinsic muscles of the tongue?
Superior longitudinal
Inferior longitudinal
Transverse
Vertical
What are the extrinsic muscles of the tongue?
Genioglossus
Hyoglossus
Styloglossus
Palatoglossus
What is the innervation of the intrinsic and extrinsic muscles of the tongue?
Hypoglossal nerve (XII)
Except palatoglossus which is innervated by vagus nerve (X)
What are the divisions of the floor of the cranial cavity?
Anterior cranial fossa
Middle cranial fossa
Posterior cranial fossa
What is the action of the genioglossus?
Inferior fibres: protrude tongue
Middle fibres: depress tongue
Superior fibres: draw tip back and down
What is the action of the hyoglossus?
Depresses and retracts tongue
What is the action of the styloglossus?
Retracts and elevates the tongue
What is the action of the palatoglossus?
Elevates posterior aspect of the tongue
What is the sensory innervation of the anterior tongue?
General sensory: Lingual nerve (Mandibular)
Special sensory: Chorda tympani (Facial)
What is the sensory innervation of the posterior tongue?
Both general and special is glossopharyngeal nerve
What is the vasculature of the tongue?
Lingual artery
Lingual vein
What 3 bones does the anterior cranial fossa consist of?
Frontal bone
Ethmoid bone
Sphenoid bone
What 3 bones does the middle cranial fossa consist of?
Sphenoid bone
2 Temporal bones
What 3 bones does the posterior cranial fossa consist of?
Occipital bone
2 Temporal bones
What are the 5 layers of the scalp?
Skin
Connective tissue dense
Aponeurosis of occipitofrontalis muscle
Loose areolar connective tissue
Periosteum
What is the arterial supply of the scalp?
External carotid artery
Ophthalmic artery
What are the branches of the external carotid artery that supply the scalp?
Superficial temporal
Posterior auricular
Occipital
What are the branches of the Opthalmic artery that supply the scalp?
Supraorbital
Supratrochlear
What is the innervation of the scalp?
Trigeminal nerve branches
cervical nerve roots
What branches of the trigeminal nerve supply the scalp?
Supratrochlear (opthalmic nerve)
Supraorbital (opthalmic nerve)
Zygomaticotemporal nerve (maxillary nerve)
Auriculotemporal nerve (mandibular nerve)
What cervical nerves supply the scalp?
Lesser occipital nerve (anterior ramus of C2)
Greater occipital nerve (posterior ramus of C2)
Great auricular nerve (anterior rami of C2 and C3)
Third occipital nerve (posterior ramus of C3)
What is CNI?
Olfactory nerve
What is CN II?
Optic nerve
What is CNIII?
Oculomotor nerve
What is CNIV?
Trochlear nerve
What is CNV?
Trigeminal nerve
What are the 3 branches of the trigeminal nerve?
Opthalmic (V1)
Maxillary (V2)
Mandibular (V3)
What are the 3 main branches of the ophthalmic nerve?
Frontal nerve- Supraorbital, Supratrochlear
Lacrimal nerve
Nasociliary nerve
What are the branches of the maxillary nerve?
Superior alveolar
Middle meningeal
Infraorbital
Zygomatic
Inferior palpebral
Superior labial
Pharyngeal
Greater and lesser palatine
Nasopalatine
What are the branches of the mandibular nerve?
Auriculotemporal
Buccal
Inferior alveolar
Lingual
What is CNVI?
Abducens nerve
What is CNVII?
Facial nerve
What is CNVIII?
Vestibulocochlear nerve
What is CNIX?
Glossopharyngeal nerve
What is CNX?
Vagus nerve
What is CNXI?
Accessory nerve
What is CNXII?
Hypoglossal nerve
What are the divisions of the ear?
External
Middle
Inner
What are the divisions of the external ear?
Auricle (pinna)
External acoustic meatus
What structures form the auricle?
Helix
Antihelix
Superior crus
Inferior crus
Tragus
Antitragus
Concha
Lobule
What part of the auricle is not cartilagenous?
Lobule
What is the concha?
Hollow depression in middle of auricle
Continues into the skull as the external acoustic meatus
Where does the external acoustic meatus extend from and to?
Extends from deep part of concha to the tympanic membrane
What are the walls of the external 1/3 of the extenral acoustic meatus?
Cartilage
What are the walls of the internal 2/3 of the external acoustic meatus?
Temporal bone
What are the coverings of the tympanic membrane?
Skin on the outside
Mucous membrane on the inside- connected to temporal bone by fibrocartilaginous ring
What attaches to the tympanic membrane?
The handle of the malleus at a point called the umbo of the tympanic membrane
What is the arterial supply of the external ear?
Branches of ECA:
- Posterior auricular
- Superficial temporal
- Occipital
- Maxillary
What is the innervation of the external ear?
Greater auricular nerve
Lesser occipital nerve
Auriculotemporal nerve
Branches of facial ad vagus nerves
What bone does the middle ear lie within?
Temporal
Where does the middle ear extend from and to?
Tympanic membrane to the lateral wall of the inner ear
What is the main function of the middle ear?
Transmit vibrations from the tympanic membrane to the inner ear via the auditory ossicles
What are the divisions of the middle ear?
Tympanic cavity- contains auditory ossicles
Epitympanic recess- space superior to tympanic cavity next to mastoid air cells
What are the auditory ossicles?
Malleus
Incus
Stapes
What is the function of the mastoid air cells?
Releases air into tympanic cavity when pressure is too low
What is the eustachian tube?
Cartilaginous and bony tube that connects the middle ear to the nasopharynx.
Also acts to equalise the pressure of the middle ear to that of the external auditory meatus
What does the inner ear contain?
The vestibulocochlear organs
What are the functions of the inner ear?
Convert mechanical signals from middle ear into electrical signals
Maintain balance
What are the 2 main components of the inner ear?
Bony labyrinth
Membranous labyrinth
What does the bony labyrinth consist of?
Cochlea
Vestibule
3 Semi-circular canals
What does the membranous labyrinth consist of?
Cochlear duct
Saccule and Utricle
Semi-circular ducts
What is the innervation of the inner ear?
Vestibulocochlear nerve (VIII)
Divides into vestibular nerve and cochlear nerve
What are the surface features of the nose?
Root
Bridge
Dorsum nasi
Ala
Apex
What is the skeleton of the nose made up of?
Bony component
Cartilagenous component
What is the internal nasal septum composed of?
Paired bones: nasal, maxillary, palatine
Unpaired bones: ethmoid, vomer
What is the arterial supply of the external nose?
Branches of facial artery:
- Maxillary arteries
- Opthelamic arteries
What is the innervation of the external nose?
Trigeminal nerve (V)
What are the paranasal sinuses?
Air filled extensions of the nasal cavity
What are the 4 paired paranasal sinuses?
Maxillary
Frontal
Sphenoid
Ethmoid
Where do the paranasal sinuses drain?
Into the nasal cavity
What is the drainage of the frontal sinuses?
Middle meatus
What is the drainage of the sphenoid sinuses?
Open into spheno-ethmoidal recess
What is the drainage of the ethmoidal sinuses?
Anterior- middle meatus
Middle- ethmoidal bulla
Posterior- superior meatus
What is the drainage of the maxillary sinuses?
Middle meatus
What are the 4 functions of the nasal cavity?
Warm and humidify air
Remove and trap pathogens
Sense of smell
Drains and clears paranasal sinuses and lacrimal ducts
What are the divisions of the nasal cavity?
Vestibule
Respiratory region
Olfactory region
What forms the floor of the nasal cavity?
Hard palate:
- Palatine bone posteriorly
- Palatine process of maxilla anteriorly
What forms the roof of the nasal cavity?
Cribriform plate of ethmoid bone
What are conchae/turbinates?
Curved shelves of bone projecting out lateral walls of the nasal cavity
Create 4 pathways for air to flow
What is the function of the conchae?
Increase surface area of nasal cavity
Disrupt fast, laminar flow of air making it slow and turbulent- air spends longer in nasal cavity so it can be hunidified
What are meatuses?
Pathways for air to flow
Created by conchae
What are the 4 meatuses?
Inferior- between inferior concha and floor of nasal cavity
Middle- between inferior and middle concha
Superior- between middle and superior concha
Spheno-ethmoidal recess- superior and posterior to superior conchae
In addition to the paranasal structures what other structures open into the nasal cavity?
Nasolacrimal duct- inferior meatus
Eustachian tube- inferior meatus
What is the arterial supply of the nose?
ICA
ECA
What is the anatomical division of the parotid duct?
Deep lobe
Superficial lobe
Separated by facial nerve
What is the other name for the parotid duct?
Stensen duct
Where does the parotid duct pierce?
Buccinator muscle and opens into the oral cavity near the second upper molar
What neurovascular structures pass through the parotid gland?
Facial nerve (VII)
ECA
Retromandibular vein
What is the arterial supply of the parotid gland?
Posterior auricular artery
Superficial temporal artery
Both are branches of ECA
What is the venous drainage of the parotid gland?
Retromandibular vein
What is the sensory innervation of the parotid gland?
Sensory: auriculotemporal nerve and greater auricular nerve
What is the autonomic innervation of the parotid gland?
Parasympathetic: Glossopharyngeal nerve synapses with otic ganglion. Auriculotemporal nerve then carries the parasympathetic fibres from the otic ganglion to the parotid gland
Sympathetic: originates from superior cervical ganglion, part of paravertebral chain
What are the borders of the sublingual glands?
Lateral: mandible
Medial: genioglossus muscle
What passes along the medial aspect of the sublingual glands?
Submandibular duct
Lingual nerve
Where do the sublingual glands drain?
Minor sublingual ducts opening out onto the sublingual folds
What is the vasculature of the sublingual glands?
Sublingual a./v. (lingual)
Submental a./v. (internal jugular)
What is the parasympathetic innervation of the sublingual glands?
Originates from the superior salivatory nucleus via chorda tympani branch of facial nerve.
Chorda tympani unifies with the lingual branch of mandibular nerve.
Synapses at submandibular ganglion
Post ganglionic secretomotor fibres
What is the sympathetic innervation of the sublingual glands?
Superior cervical ganglion
Where are the submandibular glands located?
Submandibular triangle
What is the anatomical structure of the submandibular glands?
Superficial arm
Deep arm
What muscle does the submandibular glands hook around?
Mylohyoid muscle
What is the other name for the submandibular duct?
Wharton’s duct
Where does the submandibular duct open?
Small sublingual papillae at base of lingual frenulum bilaterally
What nerves are associated with the submandibular duct?
Lingual nerve
Hypoglossal nerve
Facial nerve (marginal mandibular branch)
What is the arterial supply of the submandibular glands?
Submental artery (facial)
Sublingual (lingual)
What is the venous drainage of the submandibular glands?
Facial vein -> IJV
Sublingual vein -> lingual -> IJV
What is the innervation of the submandibular glands?
Autonomic
Same as sublingual glands
Wat does the oral cavity span between?
Oral fissure
Oropharyngeal isthmus
What are the divisions of the oral cavity?
Vestibule
Mouth proper
What is the roof of the mouth composed of?
Hard palate- bony plate
Soft palate- muscular structure
What are the cheeks of the mouth composed of?
Buccinator muscle
What is the floor of the mouth composed of?
Muscular diaphragm- mylohyoid muscles
Geniohyoid muscles
Tongue
Salivary glands and ducts
What is the innervation of the oral cavity?
All supplied by branches of trigeminal nerve (CNV)
Hard palate: Greater palatine and Nasopalatine nerve (Maxillary division)
Soft palate: Lesser palatine nerve (Maxillary division)
Floor: Lingual nerve (Mandibular division)
Cheeks: Buccal nerve (Mandibular divsion)
What forms the floor of the nasal cavity?
Hard palate
- Palatine bone posteriorly
- Palatine process of maxilla anteriorly
What is the lining of the superior palate?
Respiratory epithelium
What is the lining of the inferior palate?
Oral mucosa
What is the central process that hangs from the soft palate?
Uvula
What is the fauces?
Arched opening at the back of the mouth leading to the pharynx
What arches bind the soft palate to the tongue and pharynx?
Palatoglossal arches anteriorly
Palatopharyngeal arches posteriorly
What lies between the two arches?
Palatine tonsils
What are the muscles of the soft palate?
Tensor Veli Palatini
Levator Veli Palatini
Palatoglossus
Palatopharyngeus
Musculus Uvulae
What is the innervation of the muscles of the soft palate?
Pharyngeal branch of vagus nerve
Except Tensor Veli Palatini which is innervated by media ptterygoid nerve (Branch of CNV3)
What is the arterial supply of the palate?
Greater palatine arteries
What is the venous drainage of the palate?
Pterygoid venous plexus
What is the innervation of the palate?
Maxillary branch of trigeminal nerve
What is the primary dentition composed of?
20 teeth, 10 in each arch
What is the permanent dentition composed of?
32 teeth, 16 in each arch
What are the 2 main parts of a tooth?
Crown
Root
What covers the crown?
Enamel
What covers the root?
Cementum
What layer lies beneath the enamel and cementum?
Dentine
What are the 4 types of teeth?
Incisors
Canines
Premolars
Molars
Which bones form the boundaries of the orbit?
Frontal
Sphenoid
Lacrimal
Ethmoid
Maxilla
Zygomatic
Palatine
What forms the roof of the orbit?
Frontal bone
Lesser wing of sphenoid bone
What forms the floor of the orbit?
Maxilla
Palatine
Zygomatic
What forms the medial wall of the orbit?
Ethmoid
Maxilla
Lacrimal
Sphenoid
What forms the lateral wall of the orbit?
Zygomatic
Greater wing of sphenoid
What are the contents of the eyeballs?
Eyeballs
Extraocular muscles
Eyelids
Nerves
Blood vessels
What are the pathways into the orbit?
Optic canal
Superior orbital fissure
Inferior orbital fissure
What does the optic canal transmit?
Optic nerve
Opthalmic artery
What does the superior orbital fissure transmit?
Lacrimal nerve
Frontal nerve
Trochlear nerve (IV)
Oculomotor nerve (III)
Naso ciliary nerve
Abducens nerve (VI)
What does the inferior orbital fissure transmit?
Zygomatic branch of maxillary nerve
Inferior ophthalmic vein
Sympathetic nerves
Where do the recti muscles originate from?
Common tendinous ring
What is the attachment of the SR?
Superior and anterior aspect of slcera
What is the action of SR?
Elevation
Adduction
Medial rotation
What is the innervation of SR?
CNIII
What is the attachment of IR?
Inferior and anterior aspect of sclera
What is the actions of IR?
Depression
Adduction
Lateral rotation
What is the innervation of IR?
CNIII
What is the attachment of MR?
Anteromedial aspect of sclera
What is the action of MR?
Adducts eyeball
What is the innervation of MR?
CNIII
What is the attachment of LR?
Anterolateral aspect of sclera
What is the action of LR?
Abducts eyeball
What is the innervation of LR?
Abducens nerve (CNVI)
What is the origin and attachment of SO?
Origin: body of sphenoid bone
Insertion: posterior sclera
What is the action of SO?
Depression
Abduction
Medial rotation
What is the innervation of SO?
Trochlear nerve (CNIV)
What is the origin and attachment of IO?
Origin: orbital floor
Insertion: posterior sclera
What is the action of IO?
Elevation
Abduction
Lateral rotation
What is the innervation of IO?
Oculomotor (CNIII)
What does the fibrous layer of the eyeball consist of?
Sclera
Cornea
What does the vascular layer of the eyeball consist of?
Choroid
Ciliary body
Iris
What are the 2 fluid filled chambers in the body?
Anterior chamber
Posterior chamber
Both filled with aqueous humour
What is the vasculature of the eyeball?
Ophthalmic artery
Superior and inferior ophthalmic veins
What are the 5 main layers of the eyelid?
Skin and subcutaneous tissue
Orbicularis oculi
Tarsal plates
Levator apparatus
Conjunctiva
What are the 2 tarsal plates?
Superior tarsus- upper eyelid
Inferior tarsus- lower eyelid
What gland lies in the tarsal plates?
Meibomian glands (tarsal glands)
What is the arterial supply of the eyelid?
Rich arterial supply:
- Ophthalmic artery
- Facial artery
- Superficial temporal artery
What is the venous drainage of the eyelid?
Superficial temporal vein
What is the innervation of the upper eyelid?
Ophthalmic nerve (V1):
- Supraorbital
- Supratrochlear
- Infratrochlear
- Lacrimal
What is the innervation of the lower eyelid?
Maxillary nerve (V2):
- Infraorbital
- Zygomaticofacial
Where is the lacrimal gland located?
Anteriorly in superolateral aspect of orbit within the lacrimal fossa
What are the 2 main parts of the lacrimal gland?
Orbital
Palpebral
What is the lacrimal apparatus?
The system responsible for the drainage of lacrimal fluid from the orbit.
What is the lacrimal sac?
The dilated end of the nasolacrimal duct,
Where does the nasolacrimal duct empty?
Inferior meatus of nasal cavity
What is the arterial supply of the lacrimal gland?
Lacrimal artery (ophthalmic)
What is the venous drainage of the lacrimal gland?
Superior ophthalmic vein -> cavernous sinus
What is the sensory innervation of the lacrimal gland?
Lacrimal nerve (branch of V3)