Lab 4 Flashcards
What cranial nerves originate from the midbrain?
CN III and IV
What cranial nerve originates from the pons?
CN V
What cranial nerve originates from the medulla?
CN VI-XIII
Identify this structure:
CN II - Optic Nerve
Identify this structure:
CN III - Oculomotor Nerve
Identify this structure:
CN V - Trigeminal Nerve
Identify this structure:
Opthalamic branch of the trigeminal nerve
Identify this structure:
Maxillary branch of the trigeminal nerve
Identify this structure:
Mandibular branch of the trigeminal nerve
Identify this structure:
CN VI- abducent nerve
Identify this structure:
CN VII - Facial nerve
Identify this structure:
CN VIII - Vestibulocochlear nerve
Identify this structure:
CN IX - Glossopharyngeal nerve
Identify this structure:
CN X - Vagus nerve
Identify this structure:
CN XI - Accessory nerve
Identify this structure:
CN XII - hypoglossal nerve
Identify this structure:
pons
Identify this structure:
pyramid
Identify this structure:
trapezoid body
Identify this structure:
pyramidal decussation
If the trigeminal nerve is lesioned, what reflexes will be absent?
palpebral, corneal, or third eyelid reflex
If the abducent nerve is lesioned, what reflex will be absent?
3rd eyelid
If the facial is lesioned, what reflex will be absent?
palpebral, corneal, blinking
Identify this structure:
fourth ventricle
Identify this structure and what is its function?
pontine nucleus of the trigeminal; sensory nucleus for touch and vibration
Identify this structure:
motor nucleus of the trigeminal
Identify this structure:
trigeminal nerve
If there is a lesion to the opthalamic of the trigeminal nerve, what reflex test would you use?
corneal and palpebral
If there is a lesion on the motor nucleus of the trigeminal, what reflex tests would you use to localise it?
you wouldn’t really use one, the jaw would just be slacked
The right eye does not blink spontaneously. What specific neurological test(s)/observations allow you to localize the lesion?
facial would be damaged - 3rd eyelid test (corneal)
Both eyes blink spontaneously, but touching the right medial canthus fails to induce blinking. Where is the lesion?
on the trigeminal
Touching the nose usually triggers the animal to pull back the head. If the animal shows no problem moving the head, but does not respond to touching the nose, what nerve(s) could be injured?
the maxillary of the trigeminal
Explain why a middle ear infection could develop to facial palsy and a blinking problem.
The facial nerve innervates the stapedius muscle of the middle ear, the infection could follow the facial nerve and affect the other things that it was innervating like the eye and muscles of facial expression
Where might the lesion be in a dog that shows a lateral deviation of the tongue to the left?
left hypoglossal
When a meningioma involves the orbital fissure, what clinical signs would you expect to see?
no 3rd eyelid response, no corneal response, no palpebral response, lateral and medial strabismus because the oculomotor, trochlear, trigeminal, and abducent pass through
