Cranial Nerves Flashcards
(13 cards)
1st cranial nerve
Olfactory
Any changes to sense of smell? Lesions will cause…
Parosmia = altered sense of smell
Common cold is most frequent form of dysfunction
2nd cranial nerve
Optic acuity - 1 for each retina
Use of a Smellen chart for distant vision. Test for near vision, and colour.
Lesion would cause loss of vision
Visual inattention - ask Patient to differentiate between opening and closing fists
Visual field - one eye at a time assessing quadrant with pen.
Blind spots - same as above - large blind spot = papilloedema
Accommodation - focus on distant the near object
Papillary reflex - dimmed room, then shine light for reflex
Swinging light test - shine light between 2 eyes & pupil size should remain the same
3rd cranial nerve
Oculomotor (Test with Trochlear + Abducens)
It enables eye movements, such as focusing on an object that’s in motion, also makes it possible to move your eyes up, down and side to side.
Ptosis - eye lids drooping
H eye pattern
Cover test
Lesion = down and out of eye
4th cranial nerve
Trochlear (Tests with Abducens, and Oculomotor)
It enables movement in the eye’s superior oblique muscle. This makes it possible to look down and towards your nose or away from it.
H pattern - eye movement
Ptosis - eye droop
Cover test
Vertical diplopia
5th cranial nerve
Trigeminal
Both sensory information about facial sensation and motor information to the muscles of mastication.
Sensory - light touch
Forehead (lateral aspect): ophthalmic (V1)
Cheek: maxillary (V2)
Lower jaw (avoid the angle of the mandible as it is supplied by C2/C3): mandibular branch (V3)
Motor - Inspect, palpate Temporalis, Masseter (muscle wasting)
Open jaw against resistance. Lesion = Deviation, inability to resist
Reflex - Jaw reflex. Lesion = jaw briskly moves upwards
6th cranial nerve
Abducens (Test with Oculomotor + Trochlear)
Motor information for eye movement.
Test eye movement. H pattern and ptosis
Cover test
Lesion = results in unopposed adduction of the eye
7th cranial nerve
Facial
Transmits motor information to the muscles of facial expression and the stapedius muscle (involved in the regulation of hearing).
Sensory - recent changes to taste?
Motor - recent changes to hearing?
Facial movement - Raised eyebrows, closed eyes, blown out cheeks, smiling, pursed lips
Lesion = asymmetry
8th cranial nerve
Vestibulocochlear
Transmits sensory information about sound and balance from the inner ear to the brain.
Hearing test/3 words or 3 numbers approximately 60cms from ear.
Rinne’s test - tuning fork on mastoid process.
Weber’s test - tuning fork on forehead - sound should be hear equally in both ears.
9th cranial nerve
Glassopharyngeal (Test with Vagus)
It provides motor, parasympathetic and sensory information to your mouth and throat. Among its many functions, the nerve helps raise part of your throat, enabling swallowing.
Inspect Palate symmetry when patient says ‘AHHH’
Lesion could be - Uvula deviation
Motor - assess speech, cough swallow
Gag reflex - not necessary for test.
10th cranial nerve
Vagus (Test with Glassopharyngeal)
Transmits motor information to several muscles of the mouth which are involved in the production of speech and the efferent limb of the gag reflex.
Inspect Palate symmetry when patient says ‘AHHH’
Lesion could be - Uvula deviation
Motor - assess speech, cough swallow
Gag reflex - not necessary for test.
11th cranial nerve
Accessory
Transmits motor information to the sternocleidomastoid and trapezius muscles.
Inspect - SCM, Trapezius for muscle wasting
Motor - ask patient to turn head to each side and shrug shoulders against resistance.
12th cranial nerve
Hypoglossal
Transmits motor information to the extrinsic muscles of the tongue.
Inspect tongue while relaxed
Lesion = muscle wasting, fasciculations (lmn)
Motor - stick tongue out, move from side to side, resist pressure against cheek
Lesion = deviates to side
On On On They Travelled And Found Voldemort Guarding Very Ancient Horcruxes
Olfactory Optic Oculomotor Trochlear Trigminal Abducens Facial Vestibulocochlear Glossopharyngeal Vagal Accessory Hypoglossal
