Cranial Nerves Flashcards
CN I
Olfactory
SENSORY
Identify Familiar odors with eyes closed
Anosmia: loss of sense of smell with frontal lobe lesions
CN II
Optic
SENSORY
Test: visual fields. Use snellens chart to assess central vision, CONFRONTATION to test peripheral vision
CN III
Oculomotor
MOTOR
-Turns eye up, down, in; constricts pupil and elevates eyelid
If affected ptosis can also occur
Test: shine light in eye
-The pupillary reflex tests CNII aferrent response and CN III efferent response, accommodation and convergence
Absence of pupillary constriction in both eyes indicates CNII lesion and absent in tested eyes indicates CN III lesion
CN IV
Trochlear
MOTOR
Test: Down and in
-Double vision may occur if nerve is affected
CN V
Trigeminal
Sensory/motor
trige”m”inal - m for mastication
Test: SENSATION TO THE FACE, corneal reflex and jaw reflex (clench teeth)
-Loss of ipsilateral corneal reflex
-Deviation of jaw when opened to ipsilateral side
CN VI
Abducens
Motor
Test: Lateral gaze
CN VII
Facial
Sensory/motor
Muscles of face EXPRESSION, taste to anterior 2/3 of tongue
Test:CLOSE EYES TIGHT and smile, puff cheeks
Bell’s palsy
CN VIII
Vestibulocochlear
Sensory/motor
Test: hearing tests, balance and coordination tests, finger to nose
Webers test: test for lateralization- place vibrating tuning fork on top of head, mid position; check if sound heard in one ear or = in both
Rinne’s test: place vibrating tuning fork on mastoid bone, then close to ear canal; sound hear longer through air than bone
CN IX
Glossopharyngeal
Sensory/motor
Taste to posterior 1/3 of tongue, ability to swallow
Test: gag reflex (Affarent)
CN X
Vagus
Sensory/motor
If there is a lesion- the UVULA will deviate to the CONTRALATERAL SIDE and palate will not elevate
-Dysphagia
CN XI
Spinal Accessory nerve
Motor
Resisted shoulder shrug
CN XII
Hypoglossal
Motor
If there is a lesion the TONGUE deviates to the IPSILATERAL side and atrophy of the ipsilateral side also occurs
