Head Anatomy 1 Flashcards
What are the bones that make up the facial bones?
There are 5 facial bones:
Frontal
Zygomatic
Maxilla
Sphenoid
Ethmoid
What bones make up the orbit?
Superior= frontal bone
Inferior= maxilla
Lateral= zygomatic + sphenoid
Medial= Ethmoid
What bones make up the zygomatic arch?
Zygomatic process of temporal bone
Zygomatic bone
What space separates the sphenoid bone and maxilla in the orbit?
The infra-temporal fossa
What part of the skull base forms the ceiling of the orbit?
Anterior cranial fossa floor
What space separates the greater and lesser wings of the sphenoid bone?
Superior orbital fissure
Fracture at which area can cause an EDH due to trauma to middle meninges artery?
Which bones make up this area?
Pterion:
Frontal
Parietal
Sphenoid
Temporal
What fossa are found in the anterior cranial fossa and what structures pass through?
Cribriform plate
Olfactory nerve
What are the foramina in the middle cranial fossa?
Optic canal
Superior orbital fissure
Foramen rotundum
Foramen ovale
Foramen spinosum
What are the foramina in the posterior cranial fossa?
Carotid canal
Hypoglossal canal
Formen magnum
What fossa does the middle meningeal artery and meningeal branch of V3 (CN5) pass through?
Formen spinosum
What structures pass through the superior orbital fissure?
Occulomotor nerve
Trochlear nerve
Ophthalmic branch of trigeminal
Abducens
Ophthalmic vein
What foramen does the emissary veins and mandibular branch of trigeminal pass through?
Foramen ovale
What structures pass through the Jugular foramen?
Glossopharyngeal
Vagus
Accessory nerves
IJV
What structures pass through the foramen magnum?
Medulla
Spinal roots of CN11
Vertebral artery
Anterior and posterior spinal arteries
Cerebella’s tentorium
Apical ligament of dens
Le fort classification of patient presenting with:
Midface swelling
CSF rhinorrheoa
Mall-occlusion
Epistaxis
Le fort 2
Signs of patient with Le fort 3 fracture
Lengthening and flattening of face
Haemotympaneum
Mastoid bruising
Enophthalmos
What are the parasympathetic ganglia of the head & neck and the final structures they supply?
E ginger Westphalia- sphincter papillae & cilliary bodies
Superior salivatory- nasal & lacrimal glands + submandibular & sublingual glands
Inferior salivatory- parotid gland
What are the pre and post synaptic nerves associated with the following ganglia:
Otic
Submandibular
Cilliary
Pterygopalatine
Otic:
Pre=lesser petrosal nerve
Post= auriculotemporal
Submandibular:
Pre=chorda tympani
PST=lingual
Cilliary:
Pre= occulomotor
Post=short ciliary
Pterygopalatine:
Pre=greater petrodollars
Post=maxillary
What are the clinical signs of occulomotor nerve palsy?
-down & out pupil
Dilated pupil (mydirasis)
Between which 2 arteries does the CN3 pass between near its origin?
Posterior cerebral & superior cerebellar arteries
How would a patient with an aneurysm compressing the CN3 present initially?
-dilated pupil
-loss of accommodation
(Loss of parasympathetic control=peripheral compression)
How would a patient with diabetic neuropathy of CN3 present?
Motor symptoms;
-ptosis
-down & out pupil (extra-ocular muscles)
Middle of nerve =motor
What nerve innervates the superior oblique muscle?
Trochlear (CN4)
What does a patient with CN4 palsy present with?
Eye looking up and inwards
Unable to look down or outwards/ can look at the floor/ can’t read a book
Which nerve innervates the lateral rectus muscle?
Abducens (CN6)
What is action of lateral rectus?
Lateral gaze
What 2 spaces do CN3, 4 & 6 all pass through?
Cavernous sinus and superior orbital fissure
What artery passes through the cavernous sinus?
Internal carotid
What muscle causes inferior movement and intorsion of the eye?
Superior oblique
What muscle causes movement of the eyelid?
Le vet or palpebrae superiorioris
What are the functions of the trigeminal nerve?
Sensation to the face
Innervates muscles of mastication
What area of the face is innervated by maxillary branch of CN5?
Lower eyelid—> upper lip
What nerve gives sensation to the forehead?
Ophthalmic branch of CN5
What are all the muscles innervated by CN5?
Muscles of mastication:
-masseter
-temporalis
-medial Pterygopalatine
-lateral Pterygopalatine
Anterior belly of digastric
Mylohyoid
Tensor tympani
Tensor veil palatini
What branch of the CN5 gives motor innervation?
V3 branch
Which muscle of mastication causes:
-Opening jaw
-Closing jaw
Closing = medial, temporalis, masseter
Opening = lateral pterygoid
What area of the face does not receive sensory supply from the CN5?
What nerve supplies this area instead?
Ankle of the mandible supplied by great auricular nerve
What branch of the trigeminal nerve gives general sensation to the anterior 2/3rd of the tongue?
Lingual nerve
What type of cartilage is found at the TMJ?
Fibrocartilage
What are the types of movement seen at the TMJ?
Hinge
Sliding
What is the first neurological sign of a cavernous sinus thrombosis? Explain why.
CN6 palsy (unable to abduct eye)
Abducens is only nerve that lies inside/ medial wall of the sinus so is affected first.
What are the structures passing through the cavernous sinus?
CN3, CN4, CN V1, CNV2, CN6 and ICA
What are the causes of cavernous sinus thrombosis?
Infection (face, ear, nose)
ICA rupture
Compression (tumours, thrombosis)
Where is the cavernous sinus located?
In middle cranial fossa
On either side of the sella turcica
What are the general functions of the facial nerve?
Sensation
Motor
Parasympathetic
Which areas receive sensory supply from facial nerve?
Anterior 2/3rds of tongue (taste) via chorda tympani
Which muscles are innervated by the facial nerve?
-muscles of facial expression
+
2nd brachial arches derivatives:
-posterior belly of digastric
-stapedius
-stylohyoid
What is the function of the parasympathetic supply of CN7?
Supplies:
-lacrimal glands
-submandibular and sublingual salivary glands
What is the intra-cranial route taken by the facial nerve?
Origin: between pons & medulla
Enters internal acoustic meatus
Through facial canal
Leaves via stylomastoid foramen
What ganglion originates from fusion of motor and sensory nerve roots of CN 7?
Geniculate ganlion
What are the 3 branches given off by CN 7 inside the facial canal?
Greater petrosal nerve
Nerve to stapedius
Chorda tympani
What is the extra-cranial route taken by CN 7?
Leaves stylomastoid foramen
Turns anterior to the external ear
Runs under the parotid gland
Gives terminal branches
What are the terminal branches of the facial nerve?
Temporal
Zygomatic
Marginal mandibular
Buccal
Cervical
What are the 3 extra-cranial branches of facial nerve?
Posterior auricular
Nerve to post belly of digastric
Nerve to stylohyoid
