52 terms

Cranial Nerves

Anatomy Exam 2
Spinal Accessory
Olfactory Innervation
Sensory - from olfactory epithelium
What does Olfactory pass through?
Cribiform plate
How do you test for Olfactory?
Olfaction (Smell Test) - Use a cotton ball with alcohol (do not use something so strong it stimulates CN V by irritating nasal mucosa)
Innervation to Optic
Sensory (Vision) from retina
What does optic pass through?
Optic canal
How do we test for optic?
Menace response ( remember II in (afferent), VII out (efferent))
* Obstacle course
* Quietly roll a ball across the visual field
* Pupillary light reflex (II in and III out)
* Tracking response
Innervation to Occulomotor
Motor to Dorsal, Medial and Ventral rectus mm, ventral oblique and levator palpebrae superioris m.
* Parasympathetic to iris sphincter m.
What does occulomotor pass through?
Orbital Fissure
How do we test for Occulomotor?
Dorsal, Ventral, and medial movement of the pupil in the head (Tracking), look for lateral strabismus in lesioned animal, droopy upper eyelid, pupillary light reflex (II in and III out), including the indirect response to light in the contralateral eye
Innervation to Trochlear
Motor to dorsal oblique
What does Trochlear pass through?
Orbital Fissure
How do we test Trochlear?
Oblique deviation of pupil in lesioned animal (Not obvious in species with round pupil)
3 branchs of Trigeminal
* Ophthalmic branch
* Maxillary branch
* Mandibular Branch
Innervation of Ophthalmic branch of Trigeminal
Sensory from globe (including cornea), periorbita, nasal mucosa, medial aspect of palpebrae
Innervation of Maxillary branch of Trigeminal
Sensory from upper lip, nasal mucosa, lateral aspect of palpebrae
Innervation of Mandibular branch of Trigeminal
Sensory from the lower jaw and auriculotemporal area and motor to muscles of mastication
What does the branches of Trigeminal pass through?
Ophthalmic - orbital fissure
Maxillary - Rostral alar foramen (Round foramen)
Mandibular - Oval Foramen
How do we test for Ophthalmic branch of Trigeminal?
Palpebral reflex
Medial canthus (V in and VII out)
Corneal reflex (V in and VI out)
How do we test for Maxillary branch of Trigeminal?
Palpebral reflex
Lateral Canthus
Test sensation to upper lip or nasal mucosa
How do we test for Mandibular branch of Trigeminal?
Test sensation to the lower jaw/lip or auriculotemporal area or look for neurogenic atrophy to muscles of mastication
Innervation to Abducens
Motor to retractor bulbi m. and lateral rectus m.
What does Abducens pass through?
Orbital Fissure
How do we test Abducens?
Lateral movement of the eye(globe) in the head (tracking)
* Look for medial strabismus in lesioned animal
* Look for lack of 3rd eyelid response from the corneal reflex (V in and VI out)
Innervation to Facial
Motor to muscles of facial expression.
Sensory (taste) from the rostral 2/3 of the tongue
Parasympathetic to salivary and lacrimal gland
How do we test Facial
Effects seen on muscles of facial expression.
* Look for excessive drooling
* Deviation of philtrum
* Droopy ear
* Test palpebral reflex - failure to close the palpebral fissure in lesioned animal
Innervation to Vestibulocochlear
Sensory for hearing and balance
What does Vestibulocuchlear pass through?
Internal acoustic meatus
Test for vestibulocochlear
Test hearing.......pots and pans, etc.
* Look for vestibular signs such as nystagmus, head tilt, circling, and balance problems
Innervation to Glossopharyngeal
Sensory from tongue and pharyngeal mucosa
Motor to the pharynx
Parasympathetic to parotid and mucosal gland
What does Glossopharyngeal pass through?
Trympanooccipital Fissure via jugular foramen
How do we test glossopharyngeal
Gag Reflex
* Swallowing
* History of coughing, gaggingwhen drinking or eating
Innervation to Vagus
Motor to pharynx and esophagus
Sensory to ear canal and epiglottis
Parasympathetic to heart, lungs, and abdomen
What does the vagus pass through?
Tympanooccipital fissure via jugular foramen
How do we test the Vagus?
Listen to the heart ( Increase with lesion)
Listen to gut sounds (Decrease with lesion)
Test for gag reflex
Innervation to spinal accessory
Motor to trapezius, omotransversarious, sternocephalicus and cleidocephalicus.
Also motor to larynx via recurrent laryngeal nerve
What does spinal accessory pass through?
Tympanoocipital fissure via jugular foramen
How do we test Spinal Accessory
Neurogenic atrophy of muscles with their is a lesion
Innervation to Hypoglossal
Motor to extrinsic and intrinsic mm. of the tongue
What does Hypoglossal pass through?
Hypoglossal canal
How do we test Hypoglossal?
Tongue tone
Tongue neurogenic atrophy
Pull on tongue or watch dog lapping water