Cranial Nerve Lesions

Question 1

Olfactory Nerve CNI

Answer 1

Loss of smell

Question 2

Optic Nerve CNII

Answer 2

Blindness/visual field abnormalities (blindness/blind spots), loss of pupillary constriction (abnormal pupillary reflex)

Question 3

Oculomotor Nerve CNIII

Answer 3

Dilated pupils, ptosis, loss of normal pupillary reflexes, eye moves down inferiorly and laterally (down and out)
abnormal pupillary reflex

Question 4

Trochlear Nerve CNIV

Answer 4

Inability to look inferiorly when the eye is adducted due to paralysis of Superior Oblique muscle
diplopia, contralateral head tilt

Question 5

Trigeminal Nerve CNV

Answer 5

Loss of sensation and pain in region supplied by the three branches of the nerve over the face (trigeminal neuralgia)
loss of motor function of muscles of mastication on the side of the lesion, asymmetric jaw closing
anesthesia and dry eye

Question 6

Abducens Nerve CNVI

Answer 6

Diplopia, ipsilateral head tilting

inability of lateral eye movement

Question 7

Facial Nerve CNVII

Answer 7

Paralysis of facial muscles, abnormal taste sensation from anterior 2/3 of tongue and dry eyes
paralysis of contralateral facial muscles below the eye
hyperacusis

Question 8

Vestibulocochlear Nerve CNVIII

Answer 8

Progressive unilateral hearing loss and tinnitus (ringing in ear)

Question 9

Glossopharyngeal Nerve

Answer 9

Loss of taste to posterior 1/3 of tongue and sensation to soft palate
dysphagia, dry mouth

Question 10

Vagus Nerve CNX

Answer 10

Soft palate deviation with deviation of uvula to normal side

vocal cord paralysis, hoarseness, dysphagia

Question 11

Spinal Accessory Nerve CNXI

Answer 11

Paralysis/weakness of SCM and trapezius

Question 12

Hypoglossal Nerve CNVII

Answer 12

Atrophy of ipsilateral muscles of tongue and deviation towards affected side
dysarthria