Cranial nerves APO4 Flashcards
What is the weakest point of the neurocrainium? Why is this significant?
The pterion
middle meningeal artery flows underneath here. Trauma often results in an extradural hematoma (ie between dura and the skull)
What is the anterior cranial fossa? What does it contain what are the important structures to note?
consists of the frontal bone ethmoid bone and body of sphenoid and its two lesser wings
contains the two frontal lobes of the cerebral cortex
contains cribriform plate where olfactory bulb of CNI rests
Middle cranial fossa? What is it formed from? What are the key structures to note?
Formed from the temporal bone as well as greater wings and body of sphenoid
Temporal lobes of brain sit here
Contains the sella turcica on the body of the sphenoid that houses the pituitary gland
What passes through the optic canal?
The optic nerve (CNVII)
What passes through the superior orbital fissure?
CNIII, CNIV, CNV1, CNVI
what passes through the foramen rotundum
The maxillary nerve V2
What passes through the foramen ovale?
The mandibular nerve V3
What passes through the foramen spinosum?
Middle meningeal artery and its veins
What is the formamen magnum? What passes through it?
Largest foramen in the skull. Brain stem passes through it to link to the spinal cord
What is the hypoglossal canal? Where is it what does it contain?
Locted just inside and at the top of the foramen magnum
contains the hypoglossal nerve CNXII
What does the internal acoustic meatus contain
CNVII facial that then branches into the stylomastoid foramen
and CNVIII the vestibulocochlear
What does the jugular foramen contain?
Internal jugular vein as well as CNIX CNX CNXI
What are the names of all the cranial nerves?
Optic, olfactory, oculomotor, trochlear, trigeminal, abducens, facial, vestibulocochlear, glossopharyngeal, vagus, accessory, hypoglossal
Olfactory nerve
What does it supply
What type of nerve is it
What type of fibres does it contain
Smell specialised olfactory nerve branches from main bulb
is a sensory nerve
SVA special visceral afferent fibres –> help to mediate visceral sensations
Optic nerve
What does it supply
What type of nerve is it
What type of fibres does it contain
Vision specialised sensory cells in retina i.e. involved in vision
is a sensory nerve
SSA specialised somatic afferent derived from ectoderm
Oculomotor nerve
What does it supply
What type of nerve is it
What type of fibres does it contain
Extra-ocular muscles surrounding the eye
also muscles that allow for accommodation and pupil reflex
Motor nerve
Contains
GSE (general somatic efferent fibres innervates SK muscle)
GVE (general visceral efferent fibres supply smooth muscle and internal organs)
Trochlear
What does it supply
What type of nerve is it
What type of fibres does it contain
Superior oblique extra-ocular muscle
Motor
Contains GSE fibres
Trigeminal what are main branches and main structure
Mixed nerve sensory and motor divisions
branches into three nerves
What is the ophthalmic nerve
What does it supply
What type of nerve is it
What type of fibres does it contain
V1 branch of trigeminal nerve
Supplies conjunctiva eyes lacrimal gland supper eyelid and anterior part of scalp
Sensory
GSA fibers (general sensory afferent)
What is the maxillary nerve?
What does it supply
What type of nerve is it
What type of fibres does it contain
V2 branch of trigeminal nerve
Supplies the nasopharynx soft palate nasal cavity teeth of upper jaw skin coving the nose lower eye lid cheek and upper lip
Sensory
GSA
What is the mandibular nerve?
What does it supply
What type of nerve is it
What type of fibres does it contain
V3 branch of the trigeminal nerve
Supplies the muscles of mastication
sensory branches front the cheek lower lip anterior part of ear muscosa of the cheek the mandible (lower jaw teeth) and dura in the middle cranial fossa
SVE (special visceral efferent) or Branchial efferent
supply muscles derived from the pharyngeal arches
GSA (general somatic afferent)
Abducens nerve
What does it supply
What type of nerve is it
What type of fibres does it contain
innervates lateral rectus muscle (extra-ocular muscle)
Motor
GSE
Facial nerve CNVII
What does it supply
What type of nerve is it
What type of fibres does it contain
GSA sensory input from skin of posterior ear and around external acoustic meatus
GVE innervate lacrimal glands, mucosa of the nasal cavity
SVA innervates the anterior 2/3 of the tongue involved with taste
SVE that innervate muscles of facial expression
Mixed nerve
Vestibulocochlear
What does it supply
What type of nerve is it
What type of fibres does it contain
Supplies vestibule involved in balance as well as cochlear for hearing
Sensory
SSA (special somatic afferent) derived from ectoderm
Glossopharyngeal
What does it supply
What type of nerve is it
What type of fibres does it contain
GVA carotid body and sinus monitoring blood pressure and O2
GSA supplies posterior 1/3 of tongue taste, mucosa of middle ear, oropharynx and soft palate
SSA taste posterior 1/3 of the tongue
GVE fibres supplying salivary glands
SVE innervate muscles derived from third pharyngeal arch
Vagus
What does it supply
What type of nerve is it
What type of fibres does it contain
GSA sensory input to the larynx laryngopharynx and the auricle of the acoustic meatus as well as dura matter in the posterior cranial fossa
GVA sensory input to aortic chemoreceptors and baroreceptors as well as oesophagus bronchi heart and other abdominal viscera
SSA for taste around the epiglottis and pharynx
GVE fibers innervate smooth muscle of pharynx and larynx
SVE innervate palatoglossus muscle of tongue and the muscles of the soft palate
Accessory
What does it supply
What type of nerve is it
What type of fibres does it contain
innervates sternocleidomastoid muscles and trapezius muscles
Motor
SVE
Hypoglossal
What does it supply
What type of nerve is it
What type of fibres does it contain
all intrinsic and most of the extrinsic muscles of the tongue
Motor
GSE general somatic efferent
