9 Cranial Nerves VI-XII Flashcards
How do you test the function of the abducens nerve clinically?
Test eye movement
Patient will present with diplopia (double vision)
What might cause damage to abducens nerve (VI)?
Raised ICP
Microvascular complications eg diabetes/hypertension (Also nerves III and IV)
Why is the abducens so susceptible to raised ICP?
How is the function of the facial nerve tested for?
- Testing muscles of facial expression
- Testing corneal reflex
Ask about other symptoms:
Hyperacusis (heightened sensitivity to certain sounds)
Dry eyes
Altered taste
Why might middle ear pathology (ie in petrous bone) involve the facial nerve?
- Close relationship with vestibulocochlear neve within posterior cranial fossa and both enter internal acoustic meatus
For the corneal reflex to work, which 2 nerves need to be in tact?
How is cranial nerve VIII (vestibulocochlear) tested for clinically?
Crude hearing test- whisper number in each ear
(More formal hearing test: pure tone audiometry)
Enquire about balance (eg vertigo)
What is presbyacusis?
Old-age related hearing loss
What is an acoustic neuroma?
Benign tumour- grows from vestibular part of vestibulocochlear nerve
Gets bigger- starts to impede function of vestibulocochlear nerve
What are some symptoms of an acoustic neuroma?
Which cranial nerves exit the skull via the jugular foramen?
Where does the hypoglossal nerve exit the skull to enter the carotid sheath?
How is the gloosopharyngeal nerve (IX) tested for clinically?
(isolated lesions of CN IX) are rare
Test swallowing- (tested in conjuction with vagus nerve)
How is the Vagus nerve tested for clinically?
Check patients speech, cough and ability to swallow
Check movement of vulva and soft palate- when saying ahhhh
Identify 2 symptoms which can be caused by injury to the recurrent laryngeal nerve following thyroid surgery.
Hoarseness of voice
Dysphonia (difficulty speeaking)
How is the (spinal) accessory nerve tested for clinically?
How is the hypoglossal nerve tested for clinically?
