Cranial nerves Flashcards
(42 cards)
Which cranial nerves provide the special senses?
Olfaction (I)
Vision (II)
Taste (VII, IX and X)
Hearing and balance (VIII)
Which cranial nerves are general sensory?
Mainly V (Trigeminal) but some input to area around ear from the VII (Facial) and IX (glossopharyngeal)
Which cranial nerves have autonomic functions?
III (Pupillary costriction) VII (Lacrimation VII (Submandibular and sublingual) IX (Parotid) X (input to organs in thorax and abdomen)
What do you test in Olfactory (I) palsy?
Senso of smell
- Unilateral loss
- Bilaterall loss
What do you test in Optic (II) nerve palsy?
Visual acuity
Visual fields
Pupilary reactions
Fundoscopy
What do we test in Oculomotor (III), Trochlear (IV) and Abducens (VI) nerve palsy?
Any evidence of ptosis? Pupil of equal size? Pupillary reactions? Eye movements -Vertical and horizontal
What do we test in trigeminal (V) nerve palsy?
- Sensation in the ophthalmic, maxillary and mandibular divisions
- Power in the muscles of mastication
- Corneal reflex
- Jaw jerk
What do we test in facial (VII) nerve palsy?
Muscles of facial expression
Corneal reflex
(Taste)
What do we test in vestibulococlear (VIII) nerve palsy?
Hearing using Rinne’s and Weber’s tests
Vestibular function using Hallpike-Dix manoeuvre and Untenberger’s test
What do you test in Glossopharyngeal (IX) and Vagus (X) nerve palsy?
Movement of the palate
Gag reflex
(quality of speech)
(quality of cough)
What do you test in Accessory (XI) nerve palsy?
Head turning and shoulder shrugging (sternocleidomastoid and trapezius function)
What do you test for in Hypoglossal (XII) nerve palsy?
Appearance and movement of tongue
What cranial nerves are involved in the Pupillary light reaction?
Afferent = II Efferent = III
What cranial nerves are involved in the corneal reflex (blink reflex)?
Afferent = V Efferent = VII
What cranial nerve is involved in teh Jaw jerk?
Afferent and Efferent = V
What cranial nerves are involved in the Gag reflex?
Afferent = IX Efferent = X
Where do the nuclei of cranial nerves III and IV lie?
Midbrain
Where do the nuclei of cranial nerves V, VI and VII lie?
Pons
Where do the nuclei for the VIII cranial nerve lie?
Pontomedullary junction
Where do the cranial nerve nuclei for IX, X, XI and XII lie?
Medulla
Where can cranial nerves be damaged?
Within the brain (e.g. by ischaemia, tumour)
Crossing the sub-arachnoid space (e.g. by meningitis)
Outside the skull (e.g. by base of skull tumours arising in nasopharynx)
Bilateral III palsy indicates a problem where?
Midbrain
III + IV + VI palsy indicates a problem where
Superior orbital fissure
VI + VII palsy indicates a problem where?
Pons
