Overview Flashcards
CN-I is also called what?
Olfactory
CN-II is also called what?
Optic
Is CN-I sensory, motor, or both?
Sensory
CN-I passes through what structure?
Pass through cribiform plate of ethmoid bone (Cristae gallae sits between them)
What is unique about CN-I and CN-II that is different from the remaining cranial nerves?
They are direct extensions of the brain
Is CN-II sensory, motor, or both?
Sensory
What is the function of CN-I?
Sense of smell
Supply olfactory mucosa in superior nasal cavity
What is the function of CN-II?
Special sense of vision
CN-II passes through what structure?
Pass through optic canal
What test(s) is used to assess CN-I?
Smell test
What test(s) are used to assess CN-II?
Visual acuity
Visual fields
Fundi
Afferent limb of pupillary response
CN-III is also called what?
Oculomotor
Is CN-III sensory, motor, or both?
Motor
CN-III passes through what structure?
Pass through superior orbital
fissure
What test(s) are used to assess CN-III?
Eye movement
Accommodation
Pupil constriction
What is the function of CN-III?
Muscle movement in the eye (No lateral movement!!)
What does CN-III supply?
Inferior rectus
Medial rectus
Inferior oblique
Superior rectus
Levator papelbrae superioris
CN-IV is also called what?
Trochlear
Is CN-IV sensory, motor, or both?
Motor
What is the function of CN-IV?
Motor movement to superior oblique (Depresses, abducts, and medially
rotates the eye)
What test(s) are used to assess CN-IV?
Eye Movement
What is the smallest cranial nerve?
CN IV - Trochlear
What is the largest cranial nerve?
CN V - Trigeminal
CN-V is also called what?
Trigeminal
Is CN-V sensory, motor, or both?
Both
What test(s) are used to assess CN-V?
Corneal reflex (afferent)
Facial sensation
Test masseter and temporalis muscle by having patient bite down
What is the function of CN-V?
CN-IV comes from what structure?
Comes off the pons
What are the 3 sensory components of CN-V?
V1- ophthalmic
V2 – maxillary
V3 – mandibular
What is the motor function of CN-V?
Temporal and masseter muscle strength
Lateral movement of jaw
Name the three branches of V1 (ophthalmic branch) of CN-V
Frontal
Nasociliary
Lacrimal
V1 provides sensory information of what area(s)?
Corneal reflex
Forehead
Nasal cavity
Paranasal sinuses
V2 provides sensory information of what area(s)?
Nasal cavity
Palate
Upper teeth
Maxillary sinus
V3 provides sensory information of what area(s)?
Oral cavity
Cheek
Tongue
Lower lip
Lower teeth
Skin over mandible
V3 provides motor information of what area(s)?
Mastication muscles
Suprahyoid muscles
CN-VI is also called what?
Abducens
What is the function of CN-VI?
Abduct the eye
What test(s) are used to assess CN-VI?
Eye Movement test
Is CN-VI sensory, motor, or both?
motor
What does CN-VI supply?
Supplies lateral rectus
Where does CN-VI enter and exit?
Enters via superior orbital fissure
Exits brainstem between pons and medulla
CN-V (V3) exits where?
Exits via foramen ovale
CN-V (V2) exits where?
Exits via foramen rotundum
CN-V (V1) enters where?
Enters via superior orbital fissure
CN-VII is also called what?
Facial nerve
What is the function of CN-VII?
Motor to facial nerves and sensory
Is CN-VII sensory, motor, or both?
Both
What test(s) are used to assess CN-VII?
Raise eyebrows
Close eyes tight
Grimace
Smile
Corneal reflex (efferent)
CN-VII exits where?
Exits via internal auditory meatus and canal
What are the five branches of CN-VII?
Temporal
Zygomatic
Buccal
Mandibular
cervical
CN-VIII is also called what?
Auditory
What is the function of CN-VIII?
Hearing
Equilibrium
Motion (acceleration/deceleration)
Is CN-VIII sensory, motor, or both?
Sensory
What test(s) are used to assess CN-VIII?
Test by watch tick, finger rub
Weber-Rinne test if hearing loss noted on history or gross testing
CN-VIII exits where?
Leaves via internal auditory meatus/canal
CN-IX is also called what?
Glossopharyngeal
Is CN-IX sensory, motor, or both?
Both
What is the function of CN-IX?
Sensory (Posterior 1/3 tongue (taste), Pharynx, Middle ear, Gag reflex)
Motor (Stylopharyneus)
Parasympathetic (Jugular foramen)
CN-X is also called what?
Vagus
Is CN-X sensory, motor, or both?
Both
What is the function of CN-X?
Sensory - Larynx, External auditory meatus/canal, Heart, Great vessels, Carotid body, Sinus
Motor - Palate, Pharynx, Larynx
Parasympathetic - Viscera of thorax, Viscera of abdomen
CN-X exits where?
Exits via jugular foramen
CN-XI is also called what?
Spinal Accessory
CN-XI enters and exits where?
Enters via foramen magnum
Exits via jugular foramen
What is the function of CN-XI?
Motor to trapezium and sternocleidomastoid
Is CN-XI sensory, motor, or both?
Motor
What test(s) are used to assess CN-XI?
Shoulder shrug
Push head against resistance
CN-XII is also called what?
Hypoglossal
What is the function of CN-XII?
Motor to muscles of the tongue
What test(s) are used to assess CN-XII?
Tongue movement
Observe for fasciculations
Test strength by having the patient press tongue against the buccal mucosa on each side while you press a finger against the patient’s cheek
Is CN-XII sensory, motor, or both?
Motor
CN-XII exits where?
Exits via hypoglossal canal
What tests are used to assess the cerebellum?
Romberg test
Heel to shin test
Finger to nose
Heel and toe walking
Rapid alternating movements of UE and LE
Test strength in upper and lower extremities proximally and distally using the motor Grading system - describe grades 0-5
5 – active motion against full resistance
4 – active motion against some resistance
3 – active motion against gravity
2 – active motion with gravity eliminated
1 – barely detectable motion
0 – no motion or muscular contraction detected
Reflex testing of brachioradialis and biceps is testing what CNs?
C5-C6
Reflex testing of triceps is testing what CNs?
C7-C8
Reflex testing of quadriceps (knee) is testing what CNs?
L3-L5
Reflex testing of ankle (achilles) is testing what CNs?
S1-S2
Describe the levels of reflex testing grading system 0 to 4+
4+: hyperactive with clonus
3+: brisker than usual
2+: normal
1+: decreased or less than normal
0: absent
Name the two pathologic reflexes
Babinski Sign
Hoffman sign
Arterial circulation of the brain is separated by what?
separated by Circle of Willis
What artery(s) make up the anterior circulation?
Carotid arteries
What artery(s) make up the posterior circulation?
Vertebral arteries
Basilar arteries
What artery(s) make up the middle circulation?
Middle cerebral artery