Cranial Nerve lesions Flashcards
CN 1 - Location - Finding
Fracture of cribiform plate
Anosmia, CSF rhinorrhea
CN II - direct trauma
loss of pupillary constriction
CN II - pressure on optic pathway
Visual field defects
CN III - Location - Finding
pressure from herniating uncus on nerve, fracture involving cavernous sinus, aneurysms
Dilated pupil, ptosis, eye down and out, pupillary reflex on lesion side lost
CN IV - Location - Finding
Fracture of orbit, stretching of nerve around brainstem
inability to look down when eye is abducted
CN V - Location - Finding
Injury to terminal branches in maxillary sinus, process affecting trigeminal ganglion
Loss of pain and touch sensations, paresthesia, masssester and temporalis muscles do not contract, deviation of mandible to side of lesion
CN VII - Laceration or contusion in parotid region
Paralysis of facial muscles, eye remains open, angle of mouth droops, forehead does not wrinkle
CN VII - Fracture of temporal bone
Paralysis of facial muscles, eye remains open, angle of mouth droops, forehead does not wrinkle, dry cornea, loss of tase on anterior 2/3 of tongue
CN VII - Intracranial Hematoma
Forehead wrinkles because of bilateral innervation of frontalis muscle, paralysis of contralateral facial muscles
CN VIII - Tumor of Nerve
progressive unilater hearing loss, tinnitus
CN IX - Location - Finding
Brainsteam lesion or deep laceration of neck
Loss of tase to posterior 1/3 of tongue, loss of sensation of affected side of soft palate
CN X - Location - Finding
Brainstem lesion or deep laceration of the neck
sagging of soft palate, deviation of uvula to normal side, hoarseness due to paralysis of vocal fold
CN XI - location - finding
Laceration of neck
paralysis of SCM and descending fibers of trapezius; drooping shoulder
CN XII - Location - finding
neck laceration, fractures of cranial base
Protruded tongue which deviates toward affected side; moderate dysarthria (disturbance of articulation)
