Cranial Nerves and foramina and fissure Flashcards
all about CN and Foramina
Which Cranial nerve(s) helps with eye movement
CN III (Oculo - motor), CN IV (Trochlear), CN VI (Adbucent)
What does CN II (Optic) do?
Vision
Which Cranial nerve(s) controls facial muscles
CN VII (Facial)
Which Cranial nerves are sensory only
Cranial nerve I - olfactory, CN II - optic & CN VIII - vestibulo-cochlear
Which Cranial nerves are motor only
CN III- oculo-motor, IV - Trochlear, VI - Adbucent, XI - Accessory , XII - Hypoglossal
Which Cranial nerves carry parasympathetic fibers
CN III - Oculo-motor, CN VII - Facial, CN IX - Glosso-pharyneal, CN X -Vagus
Which nerves are not considered true Cranial nerves and why?
Olfactory & Optic, Do not have ganglia or synapses outside the central nervous system.
What does CN I do and it’s name
Smell and olfactory
Which CN nerve controls hearing and balance
Vestibulocochlear CN VIII
Which nerve is the sensory from the throat and tongue
Glosso-pharyngeal (CN IX)
What type of nerve is the Accessory nerve and where is it located
CN XI, Motor, sternocleido-mastoid and trapezius muslces
Which Cranial nerve allows tongue movement
CN XII - hypoglossal
Which nerves are found in the forebrain
Olfactory CN I & Optic CN II
Where in the brain stem would you locate CN III (Oculo-motor) & CN IV (Trochlear)
Midbrain
Which nerves are found in the pons region of the brainstem
V (Trigeminal)
VI (adbucent)
VII (Facial)
VIII (Vestibulo-cochlear)
In the Brainstem where would you locate CN IX (Glosso-pharyngeal) , CN X (Vagus), CN XI (Spinal Accessory) & CN XII (hypoglossal)
Medulla
What is the difference between nerve pathway and tracts pathway
A nerve is a nerve pathway outside the CNS. A tract is a nerve pathway within the CNS.
What are the 5 means that the vagus nerve can be disrupted
Injury or restriction to the efferent supply anywhere along it’s pathway
Sensory feedback from viscera and other sources
Toxicity
Disturbance within brainstem and brain
Psycho-emotional factors (ANS imbalance and sympathetic overstimulation)
are cranial nerves part of the CNS or PNS
PNS - All nerves are part of the PNS. including Cranial nerves
Which nerve is involved in the Meniere’s disease
CN VIII - Vestibulo-cochlear
3 diagnostic symptoms of Meniere disease
Vertigo , hearing loss and motion sickness
What is Meniere’s disease
Loss of hearing ( deafness) and attacks of tinnitus and vertigo.
which CN passes thru the ciliary ganglion
CN III - oculomotor (intrinsic muscles of the iris)
which CN passes thru the pterygopalatine ganglion
CN VII - facial - muscles of the face (lacrimal + nasal glands, mucous membrane and glands of the maxillary, ethmoid and sphenoid sinuses, palate, upper lip, gums and nasopharynx
which CN passes thru the submandibular ganglion
CN VII - facial submandibular and sublingual glands mucous membrane and glands of the mouth
which CN passes thru the otic ganglion
CN IX Glossopharyngeal - parotid gland
what fibres pass thru the pterygopalatine ganglion and where is it located
location = pterygopalatine fossa on each side, space bounded by the sphenoid, palatine bone and maxillae. Fibres = sympathetic (no synapse) parasympathetic synapse. (VII Facial nerve - glands of face and musles)
what ganglion hands down like a traffic light
pterygopalatine ganglion
Symptoms of Bell Palsy and CN involved
one side of the face drooping, difficulty controlling muscles on side of face, dribbling from one side of mouth, lower eye lid droops. CN VII Facial
Which cranial nerve is involved in secretion of saliva
CN VII - facial
Describe the pathway and type of nerve involved in pupil dilation (pupil enlargened)
CN III - oculomotor (sympathetic division)
Midbrain >middle fossa > cavernous sinus > superior orbital fissure > extrinsic and intrinsic muscles of the eye (focus and lens adjustment)
Describe the pathway and type of nerve involved in pupil constriction (pupil smaller)
CN III - oculomotor (parasympathetic division)
Midbrain >middle fossa > cavernous sinus > superior orbital fissure > branches off into the eyeball (focus and lens adjustment)
why might mumps lead to unilateral facial paraysis
mumps affect the gland. in the face this would be the parotid gland that would be affected. Facial nerve CN VII passes thru the parotid gland so can be affected by mumps
what can be the most likely cause of facial paralysis
viral infection, tumour in the brain, nerve inflammation, head injury
symptoms of trigeminal neuralgia
extreme pain in the face, stabbing, shooting, burning pain, strong electrical shocks, most commonly experienced in the maxillary and manbidular
Which nerves are involved in asthma
CN X Vagus, CN I Olfactory (allergies), CN IX glosso-pharyngeal (throat sensation), CN XI Accessory (cranial division)
CN involved in squint
Oculomotor CN III, Trochlear CN IV, Abducent CN VI
What systemic condition might affect eyesight
Diabetes 1 + 2, hypertension, graves disease, meningitis, multiple sclerosis
What structure passes thru the foramen lacerum
internal cartoid artery, cartoid nerve
what nerve passes through foramen spinosum
middle meningeal artery, recurrent meningeal branch of CN V3 Trigeminal - Mandibular nerve
which nerve raises the upper eye lid
CN III oculomotor (sympathetic division)
Which other nerve is involved in acuity of hearing
CN VII - facial . a small branch of the facail nerve connects to a tiny mucles in the middle ear (stapedius) that attached to the stapes bone. The bones role is to dampen vibrations from loud noises and levels of sound. If implicated may affect speech, language and learning difficulties may result
Where is the stylomastiod located and what passes thru it
Located = between the styloid process (posteriorly) and mastoid process (anteriorly) on the surface of the temporal bone
CN VII - facial
What factor may contribute to tinntus
stress, anxiety, trauma, phyco- emotinal trauma, infections to middle ear, trauma to surrounding membrane of ear.
Which CN are involved in digestion
CN X vagus and Accessory CN XI (cranial division)
Which CN pass thru the temporal bone
CN VII Facial , CN VIII vestibulo-cochlear (petrous portion of the temporal)
What affect does the Vagus have on the heart
regulates heart beat
which CN helps with 2/3 of the anterior taste of the tongue
CN VII Facial
which CN helps with 1/3 of the posterior taste of the tongue
CN IX Glossopharngeal
what is the carotid nerve and what is its pathway
small nerve in the neck, that innervates the carotid sinus and the carotid body. It is a branch of the glossopharyngeal nerve.
Pathway - T1-2 > synapse at the superior cervical sympathetic ganglion > carotid canal > carotid plexus > distributes to diff structures in cranium + eye
which glands are innervated by the facial nerve
Lacriminal glands of the eye, glands of the nose, mouth + sinus, mucosus glands of the nose, submandibular and sublingual glands
What does the trochlear nerve help te eye to do
(acts like a pully) look down and out
superior oblique muscle
What do the extrinsic muscle of the eye do
moves the eyeball in order to direct the gaze
which nerves supply the intrinsic muscles of the eye
CN III oculomotor
Intrinsic mucles controls the iris ad the ciliary muscles.
what detour does the recurrent laryngeal branch take
goes to the larynx, into the neck and thorax hooks under the right subclavian artery and aorta arch before returning back to the larynx
what is the cribriform plate and what fibers pass up it ?
Roof of ethmoid.
Olfactory (CN I)
Where is the optic canal located
What nerve passes through it?
Between body and lesser wing sphenoid Optic nerve (CN II)
Where is the internal auditory meatus located
in the medial wall of the petrous portion of the temporal bone.
What CN nerve passes through the internal auditory meatus
CN VIII Vestibulo - cochlear
CN VII facial nerve
Where do cranial nerves have their nucleus?
Brain and brain stem
What foramina are in the Greater wing of the Sphenoid?
Foramen Ovale; Rotundum; Spinosum
What foramina are in the Temporal Bone?
Internal Auditory Meatus
Stylomastoid Foramen
Where is the Superior orbital fissure and which cranial nerve pass through?
back of the upper orbit between the sphenoid greater wing (below) and sphenoid lesser wing (Above) CN III - oculo-motor, CN IV Trochlear, CNVI Adbucent CN V Trigeminal (ophthalmic branch)
Where is the Inferior orbital fissure and which cranial nerve pass through?
Lower part of the back of the orbit, between the sphenoid greater wing (above) and the maxilla (Below)
Trigeminal nerve Cr V2 (maxillary)
Which foramen does the mandibular branch of the trigeminal nerve (CN V3) exit from the cranium
foramen ovale - in greater wing of the sphenoid and exits at the mental foramen, recurring branch exit foramen spinosum
Describe the exit and entry point which the maxillary branch of the trigeminal nerve (CN V2) travels
exits foramen rotundum enters orbit through the inferior orbital fissure
Where is the stylomastoid foramen located and which nerve passes through it
Located between the styloid process (anteriorly) and the mastoid process (posteriorly) . Main motor branch of the facial nerve (CN VII)
Between which two bones is the jugular foramen found
occiput and mastoid process of the temporal bone.
Why is the jugular foramen vulnerable?
It is contained between two bones making it more vulnerable to compression and distortion, tension, birth trauma & head injuries in child hood and by mascular tensions at all ages.
What nerve pass through the jugular
CN IX - XI ( 9-11)
glosso-pharyneal nerve CN IX
vagus nerve CN X
spinal accessory nerve CN XI
what CN passes through foramen spinosum
Recurring branch of CN V3 trigeminal ( mandibular division)
What are the two fissure at the back of the orbit
Superior and inferior orbital fissure
What are the three foramina in the greater wing of the sphenoid
Foramen rotundum,
foramen ovale and
foramen spinosum
What Foramen is located within the occiput
Hypoglossal canal and Foramen magnum
What Foramen is located within the temporal bone
internal auditory meatus and stylomastoid foramen
what foramina are located in the sphenoid
Foramen rotundum, foramen ovale, foramen spinosum, superior orbital fissure and optic canal
What foramen does the carotid artery and nerve pass through and does it do
Foramen lacerum
provides arterial blood to the the brain. the nerve is sympathetic to the eyes and head and forms the carotid plexus
