Control lecture 4: Cranial nerves Flashcards
What are the features of CNI(1) (Olfactory)?
Location: Merge with olfactory bulbs, tracts and forebrain
Foramen: Cribriform plate
Function: Smell (olfaction)
Test: Offer a familiar smelling item
What are the features of CNII(2) (Optic)?
Location: To optic chiasma, optic tract and diencephalon
Foramen: Optic canal
Function: Vision
Test: Various visual tests
What are the features of CNIII(3) (Oculomotor)?
Location: Interpeducular fossa
Foramen: Superior orbital fissure
Function: Extraocular muscles, 4/6 (plus autonomics, see later)
Test: Follow finger test
What are the features of CNIV(4) (Trochlear)?
Location: Dorsal midbrain, inferior to the inferior colliculi
Foramen: Superior orbital fissure
Function: Superior oblique (SO4)
Test: Follow finger test
What are the features of CNV(5) (Trigeminal)?
V1: Opthalmic division
Location: Pons
Foramen: Superior orbital fissure
Function: Sensation from upper face (above eye)
Test: Cotton wool bud on forehead and corneal reflex test.
V2: Maxillary division Location: Pons Foramen: Foramen rotundum Function: Sensation from middle face (between eye and mouth) Test: Cotton wool bud on cheek
V3: Mandibular division
Location: Pons
Foramen: Foramen ovale
Function: Sensation from lower face (mandible) and motor to muscles of mastication.
Test: Cotton wool bud on jaw. Clench teeth and feel for muscle mass. Jaw jerk reflex.
What are the features of CNVI(6) (Abducens)?
Location: Pontomedullary junction
Foramen: Superior orbital fissure
Function: Lateral rectus (LR6), controls abduction of eye
Test: Follow finger test
What are the features of CNVII(7) (Facial)?
Location: Cerebellopontine angle
Foramen: Internal acoustic meatus
Function: Muscles of facial expression, taste anterior 2/3rds tongue, parasympathetic to all glands except parotid
Test: Facial movements
What are the features of CNVIII(8) (Vestibulocochlear)?
Location: Cerebellopontine angle
Foramen: Internal acoustic meatus
Function: Hearing & Balance
Test: Bedside hearing tests (Rinne’s and Weber’s test)
What are the features of CNIX(9) (Glossopharyngeal)?
Location: Posterolateral sulcus of medulla, lateral to olives
Foramen: Jugular foramen
Function: Swallowing, parasympathetic to parotid, taste posterior 1/3rd tongue, cutaneous sensation from ear, sensation from carotid body.
Test: Gag reflex
What are the features of CNX(10) (Vagus)?
Location: Posterolateral sulcus of medulla, lateral to olives
Foramen: Jugular foramen
Function: Muscles of pharynx and larynx, parasympathetic to thoracic and GI tract, taste from epiglottis and palate.
Test: Speaking, movement of uvula
What are the features of CNXI(11) (Accessory)?
Location: Caudal medulla and rostral spinal cord
Foramen: Jugular foramen
Function: Motor to SCM and trapezius
Test: Shrug shoulder and rotate head
What are the features of CNXII(12) (Hypoglossal)?
Location: Anterolateral sulcus (between pyramid and olives)
Foramen: Hypoglossal canal
Function: Motor to muscles of tongue
Test: Protrude tongue
What are the autonomic functions of the head an neck?
Sphincter pupillae of eye
Salivary glands - submandibular, sublingual and parotid
Lacrimal gland
What are the autonomic ganglia of the head and neck and which cranial nerve are they associated with?
Ciliary ganglion - III(3) (via fibres of V1)
Submandibular ganglion - VII(7) (via fibres of V2)
Pterygopalatine ganglion - VII(7) (via fibres oF V2)
Otic ganglion - IX(9) (via fibres of V3)
Associated with trigeminal nerve.
Which cranial nerves contain autonomic fibres?
Oculomotor
Facial
Glossopharyngeal
Vagus
