Cranial Nerve Lesions

Question 1

Injury to cribriform plate results in loss of smell (anosmia)

Answer 1

—olfactory nerve injury

Question 2

Direct trauma to the orbit–or its pathway results in:

Blindness/visual field abnormalities, loss of pupil constriction

Answer 2

—optic nerve injury

Question 3

aneurysm in posterior communicating, posterior cerebral, or superior cerebellar artery; herniating cerebral uncus (false localizing sign) OR cavernous sinus thrombosis or mass results in:
dilated pupil, ptosis, loss of normal pupillary reflex, eye moves down and out—

Answer 3

oculomotor nerve injury

Question 4

Orbital fracture, along the course of the nerve around the brainstem results in:

inability to look inferiorly when the eye is adducted

Answer 4

trochlear nerve

Question 5

lesion in the trigeminal ganglion..

results in loss of sensation in the three different regions in which its branches supply over the face and loss of mastication on the side of where the lesion is

Answer 5

injury to trigeminal nerve

Question 6

brain lesion or cavernous sinus lesion extending onto the orbit results in inability to lateral move the eye

Answer 6

abducens nerve

Question 7

Damages to the branches within the carotid gland; Injury to temporal bone; viral inflammation of nerve; Brainstem injury results in

paralysis of facial muscles (below the eye)

abnormal taste sensation from anterior 2/3 of tongue and dry conjunctivae—

Answer 7

facial nerve injury

Question 8

tumor at cerebellopontine angle results in progressive hearing loss and ringing of the ear (tinnitus)–

Answer 8

Vestibulochoclear nerve

Question 9

brainstem lesion and penetrating neck injury results in a loss of taste to posterior 1/3 of tongue and sensation of soft palate

Answer 9

lesion of glossopharyngeal nerve

Question 10

brainstem lesion, penetrating neck injury results in soft palate deviation with deviation of the uvulva to the normal side; vocal cord paralysis

Answer 10

lesion of vagus nerve

Question 11

penetrating injury to the posterior triangle of the neck causing paralysis of sternocleidomastoid and trapezius muscles

Answer 11

accessory nerve

Question 12

penetrating injury to the neck and base of skull results in atrophy of ipsilateral muscles of the tongue and deviation toward affected side; speech disturbance

Answer 12

hypoglossal nerve